GI Oncology

SAN DIEGO — Molecular residual disease (MRD) positivity, as detected via circulating tumor (ct) DNA following curative resection, was significantly associated with improved disease-free survival after chemotherapy in patients with stage II or III colorectal cancer (CRC), the results of the BESPOKE study showed.

“These findings highlight the value of utilizing ctDNA to select which patients should receive management chemotherapy and which patients can be potentially spared chemotherapy’s physical, emotional, and financial toxicities without compromising their long-term outcomes,” said first author Kim Magee of Natera, a clinical genetic testing company in Austin, Texas.

“ctDNA is emerging as the most powerful and prognostic biomarker in colorectal cancer,” said Magee, who presented the findings at Digestive Disease Week (DDW) 2025.

In stage II CRC, as many as 80% of patients are cured by surgery alone, while only about 5% benefit from chemotherapy. In stage III CRC, about half of patients are cured by surgery alone, while only 20% benefit from chemotherapy, and 30% recur despite chemotherapy, Magee explained.

The inability to pinpoint which patients will most benefit from chemotherapy means “we know we are needlessly treating [many] of these patients,” she said.

 

ctDNA Offers Insights Into Tumor’s Real-Time Status

Just as cells release fragments (cell-free DNA) into the blood as they regenerate, tumor cells also release fragments — ctDNA — which can represent a biomarker of a cancer’s current state, Magee explained.

Because the DNA fragments have a half-life of only about 2 hours, they represent a key snapshot in real time, “as opposed to imaging, which can take several weeks or months to show changes,” she said.

To determine the effects of ctDNA testing on treatment decisions and asymptomatic recurrence rates, Magee and colleagues analyzed data from the multicenter, prospective study, which used the Signatera (Natera) residual disease test.

The study included 1794 patients with resected stage II-III CRC who were treated with the standard of care between May 2020 and March 2023 who had complete clinical and laboratory data available.

ctDNA was collected 2-6 weeks post surgery and at surveillance months 2, 4, 6, and every 3 months through month 24.

Among the 1166 patients included in a final analysis, 694 (59.5%) patients received adjunctive chemotherapy, and 472 (40.5%) received no chemotherapy.

Among those with stage II CRC, a postoperative MRD positivity rate was 7.54%, while the rate in those with stage III disease was 28.35%.

Overall, 16.1% of patients had a recurrence by the trial end at 24 months.

The results showed that among patients who tested negative for ctDNA, the disease-free survival estimates were highly favorable, at 91.8% for stage II and 87.4% for stage III CRC.

Comparatively, for those who were ctDNA-positive, disease-free survival rates were just 45.9% and 35.5%, respectively, regardless of whether those patients received adjunctive chemotherapy.

At the study’s first ctDNA surveillance timepoint, patients who were ctDNA-positive with stage II and III CRC combined had substantially worse disease-free survival than patients who were ctDNA-negative (HR, 26.4; P < .0001).

 

Impact of Chemotherapy

Patients who were found to be MRD-positive on ctDNA testing and treated with chemotherapy had a 40.3% 2-year disease-free survival rate compared with just 24.7% among MRD-positive patients who did not receive chemotherapy.

Meanwhile, those who were MRD-negative and treated with chemotherapy had a substantially higher 2-year disease-free survival rate of 89.7% — nearly identical to the 89.5% observed in the no-chemotherapy group.

The findings underscored that “the adjuvant chemotherapy benefits were only observed among those who were ctDNA-positive,” Magee said.

“ctDNA can guide postsurgical treatment decisions by identifying which patients are most likely to benefit from chemotherapy, and in the surveillance setting, ctDNA can predict recurrence — usually ahead of scans,” she added. “This opens the opportunity to intervene and give those patients a second chance at cure.”

On the heels of major recent advances including CT, MRI, and PET-CT, “we believe that ctDNA represents the next major pivotal advancement in monitoring and eventually better understanding cancer diagnostics,” Magee said.

 

Commenting on the study, William M. Grady, MD, AGAF, medical director of the Fred Hutchinson Cancer Center Gastrointestinal Cancer Prevention Clinic, Seattle, said the BESPOKE trial represents a “well-done” study, adding to research underscoring that “MRD testing is a more accurate prognostic assay than the current standards of CT scan and CEA [carcinoembryonic antigen, a tumor marker] testing.”

However, “a limitation is that this is 2 years of follow-up, [while] 5-year follow-up data would be ideal,” he said in an interview, noting, importantly, that “a small number of patients who have no evidence of disease (NED) at 2 years develop recurrence by 5 years.”

Furthermore, more research demonstrating the outcomes of MRD detection is needed, Grady added.

“A caveat is that studies are still needed showing that if you change your care of patients based on the MRD result, that you improve outcomes,” he said. “These studies are being planned and initiated at this time, from my understanding.”

Oncologists treating patients with CRC are commonly performing MRD assessment with ctDNA assays; however, Grady noted that the practice is still not the standard of care.

Regarding the suggestion of ctDNA representing the next major, pivotal step in cancer monitoring, Grady responded that “I think this is aspirational, and further studies are needed to make this claim.”

However, “it does look like it has the promise to turn out to be true.”

Magee is an employee of Nater. Grady has been on the scientific advisory boards for Guardant Health and Freenome and has consulted for Karius.

A version of this article appeared on Medscape.com.

SAN DIEGO — Molecular residual disease (MRD) positivity, as detected via circulating tumor (ct) DNA following curative resection, was significantly associated with improved disease-free survival after chemotherapy in patients with stage II or III colorectal cancer (CRC), the results of the BESPOKE study showed.

“These findings highlight the value of utilizing ctDNA to select which patients should receive management chemotherapy and which patients can be potentially spared chemotherapy’s physical, emotional, and financial toxicities without compromising their long-term outcomes,” said first author Kim Magee of Natera, a clinical genetic testing company in Austin, Texas.

“ctDNA is emerging as the most powerful and prognostic biomarker in colorectal cancer,” said Magee, who presented the findings at Digestive Disease Week (DDW) 2025.

In stage II CRC, as many as 80% of patients are cured by surgery alone, while only about 5% benefit from chemotherapy. In stage III CRC, about half of patients are cured by surgery alone, while only 20% benefit from chemotherapy, and 30% recur despite chemotherapy, Magee explained.

The inability to pinpoint which patients will most benefit from chemotherapy means “we know we are needlessly treating [many] of these patients,” she said.

 

ctDNA Offers Insights Into Tumor’s Real-Time Status

Just as cells release fragments (cell-free DNA) into the blood as they regenerate, tumor cells also release fragments — ctDNA — which can represent a biomarker of a cancer’s current state, Magee explained.

Because the DNA fragments have a half-life of only about 2 hours, they represent a key snapshot in real time, “as opposed to imaging, which can take several weeks or months to show changes,” she said.

To determine the effects of ctDNA testing on treatment decisions and asymptomatic recurrence rates, Magee and colleagues analyzed data from the multicenter, prospective study, which used the Signatera (Natera) residual disease test.

The study included 1794 patients with resected stage II-III CRC who were treated with the standard of care between May 2020 and March 2023 who had complete clinical and laboratory data available.

ctDNA was collected 2-6 weeks post surgery and at surveillance months 2, 4, 6, and every 3 months through month 24.

Among the 1166 patients included in a final analysis, 694 (59.5%) patients received adjunctive chemotherapy, and 472 (40.5%) received no chemotherapy.

Among those with stage II CRC, a postoperative MRD positivity rate was 7.54%, while the rate in those with stage III disease was 28.35%.

Overall, 16.1% of patients had a recurrence by the trial end at 24 months.

The results showed that among patients who tested negative for ctDNA, the disease-free survival estimates were highly favorable, at 91.8% for stage II and 87.4% for stage III CRC.

Comparatively, for those who were ctDNA-positive, disease-free survival rates were just 45.9% and 35.5%, respectively, regardless of whether those patients received adjunctive chemotherapy.

At the study’s first ctDNA surveillance timepoint, patients who were ctDNA-positive with stage II and III CRC combined had substantially worse disease-free survival than patients who were ctDNA-negative (HR, 26.4; P < .0001).

 

Impact of Chemotherapy

Patients who were found to be MRD-positive on ctDNA testing and treated with chemotherapy had a 40.3% 2-year disease-free survival rate compared with just 24.7% among MRD-positive patients who did not receive chemotherapy.

Meanwhile, those who were MRD-negative and treated with chemotherapy had a substantially higher 2-year disease-free survival rate of 89.7% — nearly identical to the 89.5% observed in the no-chemotherapy group.

The findings underscored that “the adjuvant chemotherapy benefits were only observed among those who were ctDNA-positive,” Magee said.

“ctDNA can guide postsurgical treatment decisions by identifying which patients are most likely to benefit from chemotherapy, and in the surveillance setting, ctDNA can predict recurrence — usually ahead of scans,” she added. “This opens the opportunity to intervene and give those patients a second chance at cure.”

On the heels of major recent advances including CT, MRI, and PET-CT, “we believe that ctDNA represents the next major pivotal advancement in monitoring and eventually better understanding cancer diagnostics,” Magee said.

 

Commenting on the study, William M. Grady, MD, AGAF, medical director of the Fred Hutchinson Cancer Center Gastrointestinal Cancer Prevention Clinic, Seattle, said the BESPOKE trial represents a “well-done” study, adding to research underscoring that “MRD testing is a more accurate prognostic assay than the current standards of CT scan and CEA [carcinoembryonic antigen, a tumor marker] testing.”

However, “a limitation is that this is 2 years of follow-up, [while] 5-year follow-up data would be ideal,” he said in an interview, noting, importantly, that “a small number of patients who have no evidence of disease (NED) at 2 years develop recurrence by 5 years.”

Furthermore, more research demonstrating the outcomes of MRD detection is needed, Grady added.

“A caveat is that studies are still needed showing that if you change your care of patients based on the MRD result, that you improve outcomes,” he said. “These studies are being planned and initiated at this time, from my understanding.”

Oncologists treating patients with CRC are commonly performing MRD assessment with ctDNA assays; however, Grady noted that the practice is still not the standard of care.

Regarding the suggestion of ctDNA representing the next major, pivotal step in cancer monitoring, Grady responded that “I think this is aspirational, and further studies are needed to make this claim.”

However, “it does look like it has the promise to turn out to be true.”

Magee is an employee of Nater. Grady has been on the scientific advisory boards for Guardant Health and Freenome and has consulted for Karius.

A version of this article appeared on Medscape.com.

SAN DIEGO — Molecular residual disease (MRD) positivity, as detected via circulating tumor (ct) DNA following curative resection, was significantly associated with improved disease-free survival after chemotherapy in patients with stage II or III colorectal cancer (CRC), the results of the BESPOKE study showed.

“These findings highlight the value of utilizing ctDNA to select which patients should receive management chemotherapy and which patients can be potentially spared chemotherapy’s physical, emotional, and financial toxicities without compromising their long-term outcomes,” said first author Kim Magee of Natera, a clinical genetic testing company in Austin, Texas.

“ctDNA is emerging as the most powerful and prognostic biomarker in colorectal cancer,” said Magee, who presented the findings at Digestive Disease Week (DDW) 2025.

In stage II CRC, as many as 80% of patients are cured by surgery alone, while only about 5% benefit from chemotherapy. In stage III CRC, about half of patients are cured by surgery alone, while only 20% benefit from chemotherapy, and 30% recur despite chemotherapy, Magee explained.

The inability to pinpoint which patients will most benefit from chemotherapy means “we know we are needlessly treating [many] of these patients,” she said.

 

ctDNA Offers Insights Into Tumor’s Real-Time Status

Just as cells release fragments (cell-free DNA) into the blood as they regenerate, tumor cells also release fragments — ctDNA — which can represent a biomarker of a cancer’s current state, Magee explained.

Because the DNA fragments have a half-life of only about 2 hours, they represent a key snapshot in real time, “as opposed to imaging, which can take several weeks or months to show changes,” she said.

To determine the effects of ctDNA testing on treatment decisions and asymptomatic recurrence rates, Magee and colleagues analyzed data from the multicenter, prospective study, which used the Signatera (Natera) residual disease test.

The study included 1794 patients with resected stage II-III CRC who were treated with the standard of care between May 2020 and March 2023 who had complete clinical and laboratory data available.

ctDNA was collected 2-6 weeks post surgery and at surveillance months 2, 4, 6, and every 3 months through month 24.

Among the 1166 patients included in a final analysis, 694 (59.5%) patients received adjunctive chemotherapy, and 472 (40.5%) received no chemotherapy.

Among those with stage II CRC, a postoperative MRD positivity rate was 7.54%, while the rate in those with stage III disease was 28.35%.

Overall, 16.1% of patients had a recurrence by the trial end at 24 months.

The results showed that among patients who tested negative for ctDNA, the disease-free survival estimates were highly favorable, at 91.8% for stage II and 87.4% for stage III CRC.

Comparatively, for those who were ctDNA-positive, disease-free survival rates were just 45.9% and 35.5%, respectively, regardless of whether those patients received adjunctive chemotherapy.

At the study’s first ctDNA surveillance timepoint, patients who were ctDNA-positive with stage II and III CRC combined had substantially worse disease-free survival than patients who were ctDNA-negative (HR, 26.4; P < .0001).

 

Impact of Chemotherapy

Patients who were found to be MRD-positive on ctDNA testing and treated with chemotherapy had a 40.3% 2-year disease-free survival rate compared with just 24.7% among MRD-positive patients who did not receive chemotherapy.

Meanwhile, those who were MRD-negative and treated with chemotherapy had a substantially higher 2-year disease-free survival rate of 89.7% — nearly identical to the 89.5% observed in the no-chemotherapy group.

The findings underscored that “the adjuvant chemotherapy benefits were only observed among those who were ctDNA-positive,” Magee said.

“ctDNA can guide postsurgical treatment decisions by identifying which patients are most likely to benefit from chemotherapy, and in the surveillance setting, ctDNA can predict recurrence — usually ahead of scans,” she added. “This opens the opportunity to intervene and give those patients a second chance at cure.”

On the heels of major recent advances including CT, MRI, and PET-CT, “we believe that ctDNA represents the next major pivotal advancement in monitoring and eventually better understanding cancer diagnostics,” Magee said.

 

Commenting on the study, William M. Grady, MD, AGAF, medical director of the Fred Hutchinson Cancer Center Gastrointestinal Cancer Prevention Clinic, Seattle, said the BESPOKE trial represents a “well-done” study, adding to research underscoring that “MRD testing is a more accurate prognostic assay than the current standards of CT scan and CEA [carcinoembryonic antigen, a tumor marker] testing.”

However, “a limitation is that this is 2 years of follow-up, [while] 5-year follow-up data would be ideal,” he said in an interview, noting, importantly, that “a small number of patients who have no evidence of disease (NED) at 2 years develop recurrence by 5 years.”

Furthermore, more research demonstrating the outcomes of MRD detection is needed, Grady added.

“A caveat is that studies are still needed showing that if you change your care of patients based on the MRD result, that you improve outcomes,” he said. “These studies are being planned and initiated at this time, from my understanding.”

Oncologists treating patients with CRC are commonly performing MRD assessment with ctDNA assays; however, Grady noted that the practice is still not the standard of care.

Regarding the suggestion of ctDNA representing the next major, pivotal step in cancer monitoring, Grady responded that “I think this is aspirational, and further studies are needed to make this claim.”

However, “it does look like it has the promise to turn out to be true.”

Magee is an employee of Nater. Grady has been on the scientific advisory boards for Guardant Health and Freenome and has consulted for Karius.

A version of this article appeared on Medscape.com.

Clinicians can help reduce gastric cancer incidence and mortality in high-risk groups through endoscopic screening and surveillance of precancerous conditions, such as gastric intestinal metaplasia (GIM), according to a new clinical practice update from AGA.

The update supports additional gastric guidance published so far in 2025, including a clinical guideline on the diagnosis and management of gastric premalignant conditions (GPMC) from the American College of Gastroenterology (ACG) and upper GI endoscopy quality indicators from ACG and the American Society for Gastrointestinal Endoscopy (ASGE).

“The synergy of these three publications coming out at the same time helps us to finally establish surveillance of high-risk gastric conditions in practice, as we do in the colon and esophagus,” said Douglas R. Morgan, MD, professor of medicine in gastroenterology and hepatology and director of Global Health programs in gastroenterology at the University of Alabama at Birmingham.

Morgan, who wasn’t involved with the AGA update, served as lead author for the ACG guideline and co-author of the ACG-ASGE quality indicators. He also co-authored the 2024 ACG clinical guideline on treating Helicobacter pylori infection, which has implications for gastric cancer.

“The AGA and ACG updates provide detail, while the QI document is an enforcer with medical, legal, and reimbursement implications,” he said. “We have an alignment of the stars with this overdue move toward concrete surveillance for high-risk lesions in the stomach.”

The clinical practice update was published in Gastroenterology.

 

Gastric Cancer Screening

Gastric cancer remains a leading cause of preventable cancer and mortality in certain US populations, the authors wrote. The top ways to reduce mortality include primary prevention, particularly by eradicating H pylori, and secondary prevention through screening and surveillance.

High-risk groups in the United States should be considered for gastric cancer screening, including first-generation immigrants from high-incidence regions and potentially other non-White racial and ethnic groups, those with a family history of gastric cancer in a first-degree relative, and those with certain hereditary GI polyposis or hereditary cancer syndromes.

Endoscopy remains the best test for screening or surveillance of high-risk groups, the authors wrote, since it allows for direct visualization to endoscopically stage the mucosa, identify any concerning areas of neoplasia, and enable biopsies. Both endoscopic and histologic staging are key for risk stratification and surveillance decisions.

In particular, clinicians should use a high-definition white light endoscopy system with image enhancement, gastric mucosal cleansing, and insufflation to see the mucosa. As part of this, clinicians should allow for adequate visual inspection time, photodocumentation, and systematic biopsy protocol for mucosal staging, where appropriate.

As part of this, clinicians should consider H pylori eradication as an essential adjunct to endoscopic screening, the authors wrote. Opportunistic screening for H pylori should be considered in high-risk groups, and familial-based testing should be considered among adult household members of patients who test positive for H pylori.

 

Endoscopic Biopsy and Diagnosis

In patients with suspected gastric atrophy — with or without GIM — gastric biopsies should be obtained with a systematic approach, the authors wrote. Clinicians should take a minimum of five biopsies, sampling from the antrum/incisura and corpus.

Endoscopists should work with their pathologists on consistent documentation of histologic risk-stratification parameters when atrophic gastritis is diagnosed, the authors wrote. To inform clinical decision-making, this should include documentation of the presence or absence of H pylori infection, severity of atrophy or metaplasia, and histologic subtyping of GIM.

Although GIM and dysplasia are endoscopically detectable, these findings often go undiagnosed when endoscopists aren’t familiar with the characteristic visual features, the authors wrote. More training is needed, especially in the US, and although artificial intelligence tools appear promising for detecting early gastric neoplasia, data remain too preliminary to recommend routine use, the authors added.

Since indefinite and low-grade dysplasia can be difficult to identify by endoscopy and accurately diagnosis on histopathology, all dysplasia should be confirmed by an experienced gastrointestinal pathologist, the authors wrote. Clinicians should refer patients with visible or nonvisible dysplasia to an endoscopist or center with expertise in gastric neoplasia.

 

Endoscopic Management and Surveillance

If an index screening endoscopy doesn’t identify atrophy, GIM, or neoplasia, ongoing screening should be based on a patient’s risk factors and preferences. If the patient has a family history or multiple risk factors, ongoing screening should be considered. However, the optimal screening intervals in these scenarios aren’t well-defined.

Patients with confirmed gastric atrophy should undergo risk stratification, the authors wrote. Those with severe atrophic gastritis or multifocal/incomplete GIM would likely benefit from endoscopic surveillance, particularly if they have other risk factors such as family history. Surveillance should be considered every 3 years, though shorter intervals may be advisable for those with multiple risk factors such as severe GIM.

Patients with high-grade dysplasia or early gastric cancer should undergo endoscopic submucosal dissection (ESD), with the goal of en bloc, R0 resection to enable accurate pathologic staging and the intent to cure. Eradicating active H pylori infection is essential — but shouldn’t delay endoscopic intervention, the authors wrote.

In addition, patients with a history of successfully resected gastric dysplasia or cancer should undergo endoscopic surveillance. Although post-ESD surveillance intervals have been suggested in other recent AGA clinical practice updates, additional data are needed, particularly for US recommendations, the authors wrote.

Although type 1 gastric carcinoids in patients with atrophic gastritis are typically indolent, especially if less than 1 cm, endoscopists may consider resecting them and should resect lesions between 1and 2 cm. Patients with lesions over 2 cm should undergo cross-sectional imaging and be referred for surgical resection, given the risk for metastasis.

 

Patient-Centered Approach

The guideline authors suggested thinking about screening and surveillance on a patient-level basis. For instance, only those who are fit for endoscopic or potentially surgical treatment should be screened for gastric cancer and continued surveillance of GPMC, they wrote. If a person is no longer fit for endoscopic or surgical treatment, whether due to life expectancy or other comorbidities, then screening should be stopped.

In addition, to achieve health equity, clinicians should take a personalized approach to assess a patient’s risk for gastric cancer and determine whether to pursue screening and surveillance, the authors wrote. Modifiable risk factors — such as tobacco use, high-salt and processed food diets, and lack of health care — should also be addressed, since most of these risk factors disproportionately affect high-risk patients and represent healthcare disparities, they added.

“This update provides clinicians with a framework for understanding the natural history and epidemiology of gastric polyps, as well as guidance on best practices for the endoscopic detection and classification of gastric polyps, best practices for the endoscopic resection of gastric polyps, and best practices for endoscopic surveillance following resection,” said Hashem El-Serag, MD, professor and chair of medicine at the Baylor College of Medicine and director of the Texas Medical Center Digestive Diseases Center in Houston.

El-Serag, who wasn’t involved with the clinical practice update, has researched and published on consensus around the diagnosis and management of GIM.

“Stomach polyps are commonly found during routine endoscopic procedures. They are mostly asymptomatic and incidental, and therefore, clinicians may not be prepared ahead of time on how to deal with them,” he said. “The appropriate management requires proper identification and sampling of the polyp features and the uninvolved gastric mucosa, as well as a clear understanding of the risk factors and prognosis. Recent changes in the epidemiology and endoscopic management of gastric polyps makes this update timely and important.”

The update received no particular funding. The authors disclosed receiving grant support, having consultant relationships with, and serving in advisory roles for numerous pharmaceutical, biomedical, and biotechnology firms. Morgan and El-Serag reported having no relevant disclosures.

A version of this article appeared on Medscape.com.

Clinicians can help reduce gastric cancer incidence and mortality in high-risk groups through endoscopic screening and surveillance of precancerous conditions, such as gastric intestinal metaplasia (GIM), according to a new clinical practice update from AGA.

The update supports additional gastric guidance published so far in 2025, including a clinical guideline on the diagnosis and management of gastric premalignant conditions (GPMC) from the American College of Gastroenterology (ACG) and upper GI endoscopy quality indicators from ACG and the American Society for Gastrointestinal Endoscopy (ASGE).

“The synergy of these three publications coming out at the same time helps us to finally establish surveillance of high-risk gastric conditions in practice, as we do in the colon and esophagus,” said Douglas R. Morgan, MD, professor of medicine in gastroenterology and hepatology and director of Global Health programs in gastroenterology at the University of Alabama at Birmingham.

Morgan, who wasn’t involved with the AGA update, served as lead author for the ACG guideline and co-author of the ACG-ASGE quality indicators. He also co-authored the 2024 ACG clinical guideline on treating Helicobacter pylori infection, which has implications for gastric cancer.

“The AGA and ACG updates provide detail, while the QI document is an enforcer with medical, legal, and reimbursement implications,” he said. “We have an alignment of the stars with this overdue move toward concrete surveillance for high-risk lesions in the stomach.”

The clinical practice update was published in Gastroenterology.

 

Gastric Cancer Screening

Gastric cancer remains a leading cause of preventable cancer and mortality in certain US populations, the authors wrote. The top ways to reduce mortality include primary prevention, particularly by eradicating H pylori, and secondary prevention through screening and surveillance.

High-risk groups in the United States should be considered for gastric cancer screening, including first-generation immigrants from high-incidence regions and potentially other non-White racial and ethnic groups, those with a family history of gastric cancer in a first-degree relative, and those with certain hereditary GI polyposis or hereditary cancer syndromes.

Endoscopy remains the best test for screening or surveillance of high-risk groups, the authors wrote, since it allows for direct visualization to endoscopically stage the mucosa, identify any concerning areas of neoplasia, and enable biopsies. Both endoscopic and histologic staging are key for risk stratification and surveillance decisions.

In particular, clinicians should use a high-definition white light endoscopy system with image enhancement, gastric mucosal cleansing, and insufflation to see the mucosa. As part of this, clinicians should allow for adequate visual inspection time, photodocumentation, and systematic biopsy protocol for mucosal staging, where appropriate.

As part of this, clinicians should consider H pylori eradication as an essential adjunct to endoscopic screening, the authors wrote. Opportunistic screening for H pylori should be considered in high-risk groups, and familial-based testing should be considered among adult household members of patients who test positive for H pylori.

 

Endoscopic Biopsy and Diagnosis

In patients with suspected gastric atrophy — with or without GIM — gastric biopsies should be obtained with a systematic approach, the authors wrote. Clinicians should take a minimum of five biopsies, sampling from the antrum/incisura and corpus.

Endoscopists should work with their pathologists on consistent documentation of histologic risk-stratification parameters when atrophic gastritis is diagnosed, the authors wrote. To inform clinical decision-making, this should include documentation of the presence or absence of H pylori infection, severity of atrophy or metaplasia, and histologic subtyping of GIM.

Although GIM and dysplasia are endoscopically detectable, these findings often go undiagnosed when endoscopists aren’t familiar with the characteristic visual features, the authors wrote. More training is needed, especially in the US, and although artificial intelligence tools appear promising for detecting early gastric neoplasia, data remain too preliminary to recommend routine use, the authors added.

Since indefinite and low-grade dysplasia can be difficult to identify by endoscopy and accurately diagnosis on histopathology, all dysplasia should be confirmed by an experienced gastrointestinal pathologist, the authors wrote. Clinicians should refer patients with visible or nonvisible dysplasia to an endoscopist or center with expertise in gastric neoplasia.

 

Endoscopic Management and Surveillance

If an index screening endoscopy doesn’t identify atrophy, GIM, or neoplasia, ongoing screening should be based on a patient’s risk factors and preferences. If the patient has a family history or multiple risk factors, ongoing screening should be considered. However, the optimal screening intervals in these scenarios aren’t well-defined.

Patients with confirmed gastric atrophy should undergo risk stratification, the authors wrote. Those with severe atrophic gastritis or multifocal/incomplete GIM would likely benefit from endoscopic surveillance, particularly if they have other risk factors such as family history. Surveillance should be considered every 3 years, though shorter intervals may be advisable for those with multiple risk factors such as severe GIM.

Patients with high-grade dysplasia or early gastric cancer should undergo endoscopic submucosal dissection (ESD), with the goal of en bloc, R0 resection to enable accurate pathologic staging and the intent to cure. Eradicating active H pylori infection is essential — but shouldn’t delay endoscopic intervention, the authors wrote.

In addition, patients with a history of successfully resected gastric dysplasia or cancer should undergo endoscopic surveillance. Although post-ESD surveillance intervals have been suggested in other recent AGA clinical practice updates, additional data are needed, particularly for US recommendations, the authors wrote.

Although type 1 gastric carcinoids in patients with atrophic gastritis are typically indolent, especially if less than 1 cm, endoscopists may consider resecting them and should resect lesions between 1and 2 cm. Patients with lesions over 2 cm should undergo cross-sectional imaging and be referred for surgical resection, given the risk for metastasis.

 

Patient-Centered Approach

The guideline authors suggested thinking about screening and surveillance on a patient-level basis. For instance, only those who are fit for endoscopic or potentially surgical treatment should be screened for gastric cancer and continued surveillance of GPMC, they wrote. If a person is no longer fit for endoscopic or surgical treatment, whether due to life expectancy or other comorbidities, then screening should be stopped.

In addition, to achieve health equity, clinicians should take a personalized approach to assess a patient’s risk for gastric cancer and determine whether to pursue screening and surveillance, the authors wrote. Modifiable risk factors — such as tobacco use, high-salt and processed food diets, and lack of health care — should also be addressed, since most of these risk factors disproportionately affect high-risk patients and represent healthcare disparities, they added.

“This update provides clinicians with a framework for understanding the natural history and epidemiology of gastric polyps, as well as guidance on best practices for the endoscopic detection and classification of gastric polyps, best practices for the endoscopic resection of gastric polyps, and best practices for endoscopic surveillance following resection,” said Hashem El-Serag, MD, professor and chair of medicine at the Baylor College of Medicine and director of the Texas Medical Center Digestive Diseases Center in Houston.

El-Serag, who wasn’t involved with the clinical practice update, has researched and published on consensus around the diagnosis and management of GIM.

“Stomach polyps are commonly found during routine endoscopic procedures. They are mostly asymptomatic and incidental, and therefore, clinicians may not be prepared ahead of time on how to deal with them,” he said. “The appropriate management requires proper identification and sampling of the polyp features and the uninvolved gastric mucosa, as well as a clear understanding of the risk factors and prognosis. Recent changes in the epidemiology and endoscopic management of gastric polyps makes this update timely and important.”

The update received no particular funding. The authors disclosed receiving grant support, having consultant relationships with, and serving in advisory roles for numerous pharmaceutical, biomedical, and biotechnology firms. Morgan and El-Serag reported having no relevant disclosures.

A version of this article appeared on Medscape.com.

Clinicians can help reduce gastric cancer incidence and mortality in high-risk groups through endoscopic screening and surveillance of precancerous conditions, such as gastric intestinal metaplasia (GIM), according to a new clinical practice update from AGA.

The update supports additional gastric guidance published so far in 2025, including a clinical guideline on the diagnosis and management of gastric premalignant conditions (GPMC) from the American College of Gastroenterology (ACG) and upper GI endoscopy quality indicators from ACG and the American Society for Gastrointestinal Endoscopy (ASGE).

“The synergy of these three publications coming out at the same time helps us to finally establish surveillance of high-risk gastric conditions in practice, as we do in the colon and esophagus,” said Douglas R. Morgan, MD, professor of medicine in gastroenterology and hepatology and director of Global Health programs in gastroenterology at the University of Alabama at Birmingham.

Morgan, who wasn’t involved with the AGA update, served as lead author for the ACG guideline and co-author of the ACG-ASGE quality indicators. He also co-authored the 2024 ACG clinical guideline on treating Helicobacter pylori infection, which has implications for gastric cancer.

“The AGA and ACG updates provide detail, while the QI document is an enforcer with medical, legal, and reimbursement implications,” he said. “We have an alignment of the stars with this overdue move toward concrete surveillance for high-risk lesions in the stomach.”

The clinical practice update was published in Gastroenterology.

 

Gastric Cancer Screening

Gastric cancer remains a leading cause of preventable cancer and mortality in certain US populations, the authors wrote. The top ways to reduce mortality include primary prevention, particularly by eradicating H pylori, and secondary prevention through screening and surveillance.

High-risk groups in the United States should be considered for gastric cancer screening, including first-generation immigrants from high-incidence regions and potentially other non-White racial and ethnic groups, those with a family history of gastric cancer in a first-degree relative, and those with certain hereditary GI polyposis or hereditary cancer syndromes.

Endoscopy remains the best test for screening or surveillance of high-risk groups, the authors wrote, since it allows for direct visualization to endoscopically stage the mucosa, identify any concerning areas of neoplasia, and enable biopsies. Both endoscopic and histologic staging are key for risk stratification and surveillance decisions.

In particular, clinicians should use a high-definition white light endoscopy system with image enhancement, gastric mucosal cleansing, and insufflation to see the mucosa. As part of this, clinicians should allow for adequate visual inspection time, photodocumentation, and systematic biopsy protocol for mucosal staging, where appropriate.

As part of this, clinicians should consider H pylori eradication as an essential adjunct to endoscopic screening, the authors wrote. Opportunistic screening for H pylori should be considered in high-risk groups, and familial-based testing should be considered among adult household members of patients who test positive for H pylori.

 

Endoscopic Biopsy and Diagnosis

In patients with suspected gastric atrophy — with or without GIM — gastric biopsies should be obtained with a systematic approach, the authors wrote. Clinicians should take a minimum of five biopsies, sampling from the antrum/incisura and corpus.

Endoscopists should work with their pathologists on consistent documentation of histologic risk-stratification parameters when atrophic gastritis is diagnosed, the authors wrote. To inform clinical decision-making, this should include documentation of the presence or absence of H pylori infection, severity of atrophy or metaplasia, and histologic subtyping of GIM.

Although GIM and dysplasia are endoscopically detectable, these findings often go undiagnosed when endoscopists aren’t familiar with the characteristic visual features, the authors wrote. More training is needed, especially in the US, and although artificial intelligence tools appear promising for detecting early gastric neoplasia, data remain too preliminary to recommend routine use, the authors added.

Since indefinite and low-grade dysplasia can be difficult to identify by endoscopy and accurately diagnosis on histopathology, all dysplasia should be confirmed by an experienced gastrointestinal pathologist, the authors wrote. Clinicians should refer patients with visible or nonvisible dysplasia to an endoscopist or center with expertise in gastric neoplasia.

 

Endoscopic Management and Surveillance

If an index screening endoscopy doesn’t identify atrophy, GIM, or neoplasia, ongoing screening should be based on a patient’s risk factors and preferences. If the patient has a family history or multiple risk factors, ongoing screening should be considered. However, the optimal screening intervals in these scenarios aren’t well-defined.

Patients with confirmed gastric atrophy should undergo risk stratification, the authors wrote. Those with severe atrophic gastritis or multifocal/incomplete GIM would likely benefit from endoscopic surveillance, particularly if they have other risk factors such as family history. Surveillance should be considered every 3 years, though shorter intervals may be advisable for those with multiple risk factors such as severe GIM.

Patients with high-grade dysplasia or early gastric cancer should undergo endoscopic submucosal dissection (ESD), with the goal of en bloc, R0 resection to enable accurate pathologic staging and the intent to cure. Eradicating active H pylori infection is essential — but shouldn’t delay endoscopic intervention, the authors wrote.

In addition, patients with a history of successfully resected gastric dysplasia or cancer should undergo endoscopic surveillance. Although post-ESD surveillance intervals have been suggested in other recent AGA clinical practice updates, additional data are needed, particularly for US recommendations, the authors wrote.

Although type 1 gastric carcinoids in patients with atrophic gastritis are typically indolent, especially if less than 1 cm, endoscopists may consider resecting them and should resect lesions between 1and 2 cm. Patients with lesions over 2 cm should undergo cross-sectional imaging and be referred for surgical resection, given the risk for metastasis.

 

Patient-Centered Approach

The guideline authors suggested thinking about screening and surveillance on a patient-level basis. For instance, only those who are fit for endoscopic or potentially surgical treatment should be screened for gastric cancer and continued surveillance of GPMC, they wrote. If a person is no longer fit for endoscopic or surgical treatment, whether due to life expectancy or other comorbidities, then screening should be stopped.

In addition, to achieve health equity, clinicians should take a personalized approach to assess a patient’s risk for gastric cancer and determine whether to pursue screening and surveillance, the authors wrote. Modifiable risk factors — such as tobacco use, high-salt and processed food diets, and lack of health care — should also be addressed, since most of these risk factors disproportionately affect high-risk patients and represent healthcare disparities, they added.

“This update provides clinicians with a framework for understanding the natural history and epidemiology of gastric polyps, as well as guidance on best practices for the endoscopic detection and classification of gastric polyps, best practices for the endoscopic resection of gastric polyps, and best practices for endoscopic surveillance following resection,” said Hashem El-Serag, MD, professor and chair of medicine at the Baylor College of Medicine and director of the Texas Medical Center Digestive Diseases Center in Houston.

El-Serag, who wasn’t involved with the clinical practice update, has researched and published on consensus around the diagnosis and management of GIM.

“Stomach polyps are commonly found during routine endoscopic procedures. They are mostly asymptomatic and incidental, and therefore, clinicians may not be prepared ahead of time on how to deal with them,” he said. “The appropriate management requires proper identification and sampling of the polyp features and the uninvolved gastric mucosa, as well as a clear understanding of the risk factors and prognosis. Recent changes in the epidemiology and endoscopic management of gastric polyps makes this update timely and important.”

The update received no particular funding. The authors disclosed receiving grant support, having consultant relationships with, and serving in advisory roles for numerous pharmaceutical, biomedical, and biotechnology firms. Morgan and El-Serag reported having no relevant disclosures.

A version of this article appeared on Medscape.com.

Dear colleagues,

Many of us diagnose and treat patients with Barrett’s esophagus, estimated to affect up to 5.6% of the US adult population. There has been an expanding array of tools to help diagnose and effectively treat Barrett’s esophagus with dysplasia and malignancy. In particular, endoscopic submucosal dissection (ESD) has emerged as an important method for treating early cancer in the gastrointestinal tract.

But how do we incorporate ESD into our algorithm for management, especially with the popularity and effectiveness of endoscopic mucosal resection (EMR)? In this issue of Perspectives we aim to provide context for the use of ESD, as compared with EMR. Dr. Silvio de Melo discusses his preferred EMR technique and its many advantages in the management of BE, including for residual or refractory areas. In contrast, Dr. Mohamed Othman reviews the power of ESD and when we should consider this approach over EMR. We hope these discussions will facilitate your care for patients with Barrett’s esophagus.

We also welcome your thoughts on this topic — join the conversation on X at @AGA_GIHN. 

Gyanprakash A. Ketwaroo, MD, MSc, is associate professor of medicine, Yale University, New Haven, and chief of endoscopy at West Haven VA Medical Center, both in Connecticut. He is an associate editor for GI & Hepatology News.

Endoscopic Mucosal Resection: The ‘Workhorse’ for Patient Care

BY SILVIO W. DE MELO JR, MD, AGAF

Barrett’s esophagus (BE) remains an important clinical problem, being one of the modifiable risk factors for esophageal adenocarcinoma. The care for BE is complex and requires several steps to correctly formulate a therapeutic plan. It starts with a proper endoscopic examination. It is recommended to spend at least 1 minute inspecting and evaluating every centimeter of the salmon-colored epithelium, looking for change in vascular pattern, erosions/ulcers, nodules, and/or masses. After the inspection, random biopsies every 1-2 cm plus targeted biopsies will guide you. It is still controversial if the addition of other sampling strategies, such as brushings or confocal endomicroscopy, is needed.

The introduction of radiofrequency ablation (RFA) was paramount in popularizing the treatment options for BE and sunsetting the previous dominant modality, photodynamic therapy (PDT). RFA proved to have a superior clinical efficacy in replacing the intestinal metaplasia/BE with neosquamous epithelium while boosting a much better safety profile, compared with PDT. However, RFA is most efficacious for “flat BE” and it is not an effective, nor recommended, method to treat nodular BE or early cancer, such as carcinoma in situ or nodular high-grade dysplasia. Endoscopic mucosal resection (EMR) is utilized to overcome those limitations.

There are several techniques utilized for EMR:

• The lift and snare technique.
• The snare-in-cap technique.
• The Band-snare technique.

The free-hand submucosal lift and snare is not frequently used in the esophagus. It is difficult to maintain visualization while being confident that one has the whole lesion inside the snare and that the distal (anal side) part of the lesion is free of any unwanted tissue (to minimize complications such as perforations or unwelcomed gastric resections). It is difficult after the first resection to lift an adjacent area, as the fluid easily leaks from the first resected spot, thus removing larger lesions in piece-meal fashion is challenging. This technique can be used in small (in my personal experience, less than 5 mm) lesions, but, given that there are better and safer alternatives, I almost never use this technique for my esophageal EMR cases. I prefer to use the band-snare technique even for lesions under 5 mm.

The snare-in-cap technique has been utilized in the esophagus. In this technique, a cap is attached to the distal end of the scope and the size of the resection is determined by the size of the cap, usually under 1.5 cm. Because of the risk of perforation without previous lifting, it is required that the lesion is lifted with a submucosal fluid, saline or any Food and Drug Administration–approved EMR solution. The lesion is then suctioned inside the cap where the snare had been previously opened inside the cap, the snare is closed, and the tissue is resected. The same limitations regarding the inability to remove larger lesions (greater than 1.5 cm) because of the challenge in lifting the adjacent area applies here. However, the perforation risk for this technique is higher than the traditional lift and the band and snare techniques. Thus, this technique has fallen out of favor for most endoscopists.

The third technique (band-snare EMR) is the one that most endoscopists use for endoscopic mucosal resection. It is a small variation of the already time-tested and very familiar procedure of esophageal variceal band ligation (EVL). There are multiple commercially available kits for esophageal EMR. The kit contains the chamber with the bands and a proprietary hexagonal snare used to resect the specimen.

The advantages of this technique are:

• It is widely commercially available.
• It builds on a familiar procedure, EVL, therefore the learning curve is short.
• The set-up is quick and the procedure can be completed safely and effectively.
• There is no need for injecting the submucosal with a lifting solution.
• Despite the band having a size limitation of 1 cm, one can remove larger lesions by repeating the band and resect process, using the rosette technique.

Band-snare EMR also has limitations:

• There are only six bands on each chamber. Depending on the size of the lesion, one may need to use multiple kits.
• It is not suitable for en bloc resection of lesions greater than 1 cm.

My experience with band EMR is that we can complete the procedure in under 1 hour. The dreaded complication of perforation occurs in under 1% of cases, most bleeding episodes can easily be controlled endoscopically, and the risk of post-EMR stricture is minimal. Therefore, band EMR is the most used technique for esophageal endoscopic resections.

Esophageal EMR is also effective for other indications in BE therapy, such as residual and recurrent BE. Band-snare EMR can be used for an en bloc resection or rosette technique for the areas resistant to ablation therapies with great success and safety.

From a financial standpoint, comparing EMR with endoscopic submucosal dissection (ESD), EMR is the superior strategy given that EMR is widely available, has a much shorter learning curve, has a greater safety profile, is applicable to a wider variety of indications, and has a more favorable return on investment. EMR should be the workhorse for the care of patients with BE, reserving ESD for specific indications.

In summary, there is no “one-size-fits-all” endoscopic therapy in the care of BE. Most Barrett’s patients can be successfully treated with a combination of ablation plus EMR, reserving ESD for select cases.

Dr. de Melo is section chief of gastroenterology at the Orlando VA Healthcare System, Orlando, Florida. He declares no conflicts of interest.

ESD Over EMR for Resecting Esophageal Lesions

BY MOHAMED O. OTHMAN, MD, AGAF

Although endoscopic submucosal dissection (ESD) is the preferred endoscopic resection method in the East, the adoption of this technique in the West, particularly in the United States, has faced many hurdles. Many endoscopists who routinely perform piecemeal endoscopic mucosal resection (EMR) question the utility of ESD, arguing that EMR is just as effective. While this may hold true in certain situations, the global trend in the endoscopic treatment of early esophageal squamous cell carcinoma, nodular Barrett’s esophagus (BE), and early esophageal adenocarcinoma (EAC) has clearly shifted toward ESD. In this perspective, I will summarize why ESD is preferred over EMR for these indications and explore why ESD has yet to gain widespread adoption in the United States.

The superiority of ESD over EMR has been well established in multiple publications from both Eastern and Western literature. Mejia-Perez et al, in a multicenter cohort study from eight centers in North America, compared outcomes of ESD vs EMR for BE with high-grade dysplasia (HGD) or T1a adenocarcinoma in 243 patients. ESD achieved significantly higher en bloc resection rates (89% vs 43%) and R0 resection rates (73% vs 56%), compared with EMR, along with a substantially lower recurrence/residual disease rate on follow-up (3.5% in the ESD group vs 31.4% in EMR group). Additionally, more patients required repeat endoscopic resection after EMR to treat residual or recurrent disease (EMR, 24.2% vs ESD, 3.5%; P < .001).

Han et al conducted a meta-analysis of 22 studies comparing ESD and EMR for early esophageal neoplasia, including both squamous cell carcinoma (SCC) and BE-associated lesions. ESD was associated with significantly higher curative resection rates than EMR (OR, 9.74; 95% CI, 4.83-19.62; P < .0001). Of note, lesion size was a critical factor in determining the advantage of ESD. For lesions ≤ 10 mm, curative resection rates were comparable between ESD and EMR. However, for lesions > 10 mm, ESD achieved significantly higher curative resection rates. This size-based recommendation has been adopted by the American Society of Gastrointestinal Endoscopy (ASGE) in their recent guidelines on ESD indications for esophageal lesions. ASGE guidelines favors ESD over EMR for SCC lesions > 15 mm and for nodular BE with dysplasia or early EAC > 20 mm.

ESD is particularly beneficial in patients who develop early adenocarcinoma after RFA or EMR. Mesureur et al evaluated the efficacy of salvage ESD for Barrett’s recurrence or residual BE following RFA. In their multicenter retrospective study of 56 patients, salvage ESD achieved an en bloc resection rate of 89.3%, despite significant fibrosis, with an R0 resection rate of 66%. At a median follow-up of 14 months, most patients remained in endoscopic remission without the need for esophagectomy.

Combining ESD with RFA has also been shown to accelerate the eradication of BE with dysplasia while reducing the number of required sessions. Our group demonstrated the high efficacy of ESD followed by RFA in 18 patients, most of whom had long-segment BE with HGD or EAC. On average, patients required only one to two RFA sessions after ESD to achieve complete eradication of intestinal metaplasia (CE-IM). Over a median follow-up of 42.5 months (IQR, 28-59.25), complete eradication of early esophageal cancer was achieved in 13 patients (100%), eradication of dysplasia in 15 patients (100%), and CE-IM in 14 patients (77.8%).

Despite the overwhelming evidence supporting ESD and the strong endorsement from professional societies, adoption in the West continues to lag. Several factors contribute to this gap. First, ESD has a steep learning curve. Our data showed that, on average, an untutored practitioner achieved competency after 150-250 procedures, a finding corroborated by other US groups.

Second, there is no specific CPT code for ESD in the United States. Physicians are forced to bill the procedure as EMR or use an unlisted code, resulting in reimbursement that does not reflect the time and complexity of the procedure. Our group showed that physician reimbursement for ESD is highly variable, ranging from $50 to $800 per case, depending on insurance type.

Third, the increasing emphasis on productivity and RVU generation in academic settings has hindered the growth of ESD training in many institutions. Still, the outlook for ESD in the United States remains encouraging. Multiple industry-sponsored training courses are held annually, and professional societies are investing heavily in expanding access to structured education in ESD. Industry is also innovating devices that improve procedural efficiency and safety. Adopting novel approaches, such as traction-assisted ESD, has made the technique more appealing to endoscopists concerned about long procedure times. For example, our group proposed a standardized esophageal ESD technique that incorporates specimen self-retraction. This method improves both safety and speed and has helped address several procedural challenges. We’ve demonstrated that consistency in technique can substantially expedite esophageal ESD.

Fast forward 5 years: We anticipate a dedicated CPT code for ESD, broader access to advanced resection tools, and an expanding number of fellowships offering structured ESD training. These developments are poised to eliminate many of the current barriers. In summary, with robust data supporting the efficacy of ESD in early esophageal cancer, the focus in the United States should shift toward mastering and integrating the technique, rather than dismissing it in favor of piecemeal EMR.

Dr. Othman is chief of the gastroenterology and hepatology section at Baylor College of Medicine and Medicine Subspecialities Service Line Chief at Baylor St Luke’s Medical Center, both in Houston. He declares no conflicts of interest.

Dear colleagues,

Many of us diagnose and treat patients with Barrett’s esophagus, estimated to affect up to 5.6% of the US adult population. There has been an expanding array of tools to help diagnose and effectively treat Barrett’s esophagus with dysplasia and malignancy. In particular, endoscopic submucosal dissection (ESD) has emerged as an important method for treating early cancer in the gastrointestinal tract.

But how do we incorporate ESD into our algorithm for management, especially with the popularity and effectiveness of endoscopic mucosal resection (EMR)? In this issue of Perspectives we aim to provide context for the use of ESD, as compared with EMR. Dr. Silvio de Melo discusses his preferred EMR technique and its many advantages in the management of BE, including for residual or refractory areas. In contrast, Dr. Mohamed Othman reviews the power of ESD and when we should consider this approach over EMR. We hope these discussions will facilitate your care for patients with Barrett’s esophagus.

We also welcome your thoughts on this topic — join the conversation on X at @AGA_GIHN. 

Gyanprakash A. Ketwaroo, MD, MSc, is associate professor of medicine, Yale University, New Haven, and chief of endoscopy at West Haven VA Medical Center, both in Connecticut. He is an associate editor for GI & Hepatology News.

Endoscopic Mucosal Resection: The ‘Workhorse’ for Patient Care

BY SILVIO W. DE MELO JR, MD, AGAF

Barrett’s esophagus (BE) remains an important clinical problem, being one of the modifiable risk factors for esophageal adenocarcinoma. The care for BE is complex and requires several steps to correctly formulate a therapeutic plan. It starts with a proper endoscopic examination. It is recommended to spend at least 1 minute inspecting and evaluating every centimeter of the salmon-colored epithelium, looking for change in vascular pattern, erosions/ulcers, nodules, and/or masses. After the inspection, random biopsies every 1-2 cm plus targeted biopsies will guide you. It is still controversial if the addition of other sampling strategies, such as brushings or confocal endomicroscopy, is needed.

The introduction of radiofrequency ablation (RFA) was paramount in popularizing the treatment options for BE and sunsetting the previous dominant modality, photodynamic therapy (PDT). RFA proved to have a superior clinical efficacy in replacing the intestinal metaplasia/BE with neosquamous epithelium while boosting a much better safety profile, compared with PDT. However, RFA is most efficacious for “flat BE” and it is not an effective, nor recommended, method to treat nodular BE or early cancer, such as carcinoma in situ or nodular high-grade dysplasia. Endoscopic mucosal resection (EMR) is utilized to overcome those limitations.

There are several techniques utilized for EMR:

• The lift and snare technique.
• The snare-in-cap technique.
• The Band-snare technique.

The free-hand submucosal lift and snare is not frequently used in the esophagus. It is difficult to maintain visualization while being confident that one has the whole lesion inside the snare and that the distal (anal side) part of the lesion is free of any unwanted tissue (to minimize complications such as perforations or unwelcomed gastric resections). It is difficult after the first resection to lift an adjacent area, as the fluid easily leaks from the first resected spot, thus removing larger lesions in piece-meal fashion is challenging. This technique can be used in small (in my personal experience, less than 5 mm) lesions, but, given that there are better and safer alternatives, I almost never use this technique for my esophageal EMR cases. I prefer to use the band-snare technique even for lesions under 5 mm.

The snare-in-cap technique has been utilized in the esophagus. In this technique, a cap is attached to the distal end of the scope and the size of the resection is determined by the size of the cap, usually under 1.5 cm. Because of the risk of perforation without previous lifting, it is required that the lesion is lifted with a submucosal fluid, saline or any Food and Drug Administration–approved EMR solution. The lesion is then suctioned inside the cap where the snare had been previously opened inside the cap, the snare is closed, and the tissue is resected. The same limitations regarding the inability to remove larger lesions (greater than 1.5 cm) because of the challenge in lifting the adjacent area applies here. However, the perforation risk for this technique is higher than the traditional lift and the band and snare techniques. Thus, this technique has fallen out of favor for most endoscopists.

The third technique (band-snare EMR) is the one that most endoscopists use for endoscopic mucosal resection. It is a small variation of the already time-tested and very familiar procedure of esophageal variceal band ligation (EVL). There are multiple commercially available kits for esophageal EMR. The kit contains the chamber with the bands and a proprietary hexagonal snare used to resect the specimen.

The advantages of this technique are:

• It is widely commercially available.
• It builds on a familiar procedure, EVL, therefore the learning curve is short.
• The set-up is quick and the procedure can be completed safely and effectively.
• There is no need for injecting the submucosal with a lifting solution.
• Despite the band having a size limitation of 1 cm, one can remove larger lesions by repeating the band and resect process, using the rosette technique.

Band-snare EMR also has limitations:

• There are only six bands on each chamber. Depending on the size of the lesion, one may need to use multiple kits.
• It is not suitable for en bloc resection of lesions greater than 1 cm.

My experience with band EMR is that we can complete the procedure in under 1 hour. The dreaded complication of perforation occurs in under 1% of cases, most bleeding episodes can easily be controlled endoscopically, and the risk of post-EMR stricture is minimal. Therefore, band EMR is the most used technique for esophageal endoscopic resections.

Esophageal EMR is also effective for other indications in BE therapy, such as residual and recurrent BE. Band-snare EMR can be used for an en bloc resection or rosette technique for the areas resistant to ablation therapies with great success and safety.

From a financial standpoint, comparing EMR with endoscopic submucosal dissection (ESD), EMR is the superior strategy given that EMR is widely available, has a much shorter learning curve, has a greater safety profile, is applicable to a wider variety of indications, and has a more favorable return on investment. EMR should be the workhorse for the care of patients with BE, reserving ESD for specific indications.

In summary, there is no “one-size-fits-all” endoscopic therapy in the care of BE. Most Barrett’s patients can be successfully treated with a combination of ablation plus EMR, reserving ESD for select cases.

Dr. de Melo is section chief of gastroenterology at the Orlando VA Healthcare System, Orlando, Florida. He declares no conflicts of interest.

ESD Over EMR for Resecting Esophageal Lesions

BY MOHAMED O. OTHMAN, MD, AGAF

Although endoscopic submucosal dissection (ESD) is the preferred endoscopic resection method in the East, the adoption of this technique in the West, particularly in the United States, has faced many hurdles. Many endoscopists who routinely perform piecemeal endoscopic mucosal resection (EMR) question the utility of ESD, arguing that EMR is just as effective. While this may hold true in certain situations, the global trend in the endoscopic treatment of early esophageal squamous cell carcinoma, nodular Barrett’s esophagus (BE), and early esophageal adenocarcinoma (EAC) has clearly shifted toward ESD. In this perspective, I will summarize why ESD is preferred over EMR for these indications and explore why ESD has yet to gain widespread adoption in the United States.

The superiority of ESD over EMR has been well established in multiple publications from both Eastern and Western literature. Mejia-Perez et al, in a multicenter cohort study from eight centers in North America, compared outcomes of ESD vs EMR for BE with high-grade dysplasia (HGD) or T1a adenocarcinoma in 243 patients. ESD achieved significantly higher en bloc resection rates (89% vs 43%) and R0 resection rates (73% vs 56%), compared with EMR, along with a substantially lower recurrence/residual disease rate on follow-up (3.5% in the ESD group vs 31.4% in EMR group). Additionally, more patients required repeat endoscopic resection after EMR to treat residual or recurrent disease (EMR, 24.2% vs ESD, 3.5%; P < .001).

Han et al conducted a meta-analysis of 22 studies comparing ESD and EMR for early esophageal neoplasia, including both squamous cell carcinoma (SCC) and BE-associated lesions. ESD was associated with significantly higher curative resection rates than EMR (OR, 9.74; 95% CI, 4.83-19.62; P < .0001). Of note, lesion size was a critical factor in determining the advantage of ESD. For lesions ≤ 10 mm, curative resection rates were comparable between ESD and EMR. However, for lesions > 10 mm, ESD achieved significantly higher curative resection rates. This size-based recommendation has been adopted by the American Society of Gastrointestinal Endoscopy (ASGE) in their recent guidelines on ESD indications for esophageal lesions. ASGE guidelines favors ESD over EMR for SCC lesions > 15 mm and for nodular BE with dysplasia or early EAC > 20 mm.

ESD is particularly beneficial in patients who develop early adenocarcinoma after RFA or EMR. Mesureur et al evaluated the efficacy of salvage ESD for Barrett’s recurrence or residual BE following RFA. In their multicenter retrospective study of 56 patients, salvage ESD achieved an en bloc resection rate of 89.3%, despite significant fibrosis, with an R0 resection rate of 66%. At a median follow-up of 14 months, most patients remained in endoscopic remission without the need for esophagectomy.

Combining ESD with RFA has also been shown to accelerate the eradication of BE with dysplasia while reducing the number of required sessions. Our group demonstrated the high efficacy of ESD followed by RFA in 18 patients, most of whom had long-segment BE with HGD or EAC. On average, patients required only one to two RFA sessions after ESD to achieve complete eradication of intestinal metaplasia (CE-IM). Over a median follow-up of 42.5 months (IQR, 28-59.25), complete eradication of early esophageal cancer was achieved in 13 patients (100%), eradication of dysplasia in 15 patients (100%), and CE-IM in 14 patients (77.8%).

Despite the overwhelming evidence supporting ESD and the strong endorsement from professional societies, adoption in the West continues to lag. Several factors contribute to this gap. First, ESD has a steep learning curve. Our data showed that, on average, an untutored practitioner achieved competency after 150-250 procedures, a finding corroborated by other US groups.

Second, there is no specific CPT code for ESD in the United States. Physicians are forced to bill the procedure as EMR or use an unlisted code, resulting in reimbursement that does not reflect the time and complexity of the procedure. Our group showed that physician reimbursement for ESD is highly variable, ranging from $50 to $800 per case, depending on insurance type.

Third, the increasing emphasis on productivity and RVU generation in academic settings has hindered the growth of ESD training in many institutions. Still, the outlook for ESD in the United States remains encouraging. Multiple industry-sponsored training courses are held annually, and professional societies are investing heavily in expanding access to structured education in ESD. Industry is also innovating devices that improve procedural efficiency and safety. Adopting novel approaches, such as traction-assisted ESD, has made the technique more appealing to endoscopists concerned about long procedure times. For example, our group proposed a standardized esophageal ESD technique that incorporates specimen self-retraction. This method improves both safety and speed and has helped address several procedural challenges. We’ve demonstrated that consistency in technique can substantially expedite esophageal ESD.

Fast forward 5 years: We anticipate a dedicated CPT code for ESD, broader access to advanced resection tools, and an expanding number of fellowships offering structured ESD training. These developments are poised to eliminate many of the current barriers. In summary, with robust data supporting the efficacy of ESD in early esophageal cancer, the focus in the United States should shift toward mastering and integrating the technique, rather than dismissing it in favor of piecemeal EMR.

Dr. Othman is chief of the gastroenterology and hepatology section at Baylor College of Medicine and Medicine Subspecialities Service Line Chief at Baylor St Luke’s Medical Center, both in Houston. He declares no conflicts of interest.

Dear colleagues,

Many of us diagnose and treat patients with Barrett’s esophagus, estimated to affect up to 5.6% of the US adult population. There has been an expanding array of tools to help diagnose and effectively treat Barrett’s esophagus with dysplasia and malignancy. In particular, endoscopic submucosal dissection (ESD) has emerged as an important method for treating early cancer in the gastrointestinal tract.

But how do we incorporate ESD into our algorithm for management, especially with the popularity and effectiveness of endoscopic mucosal resection (EMR)? In this issue of Perspectives we aim to provide context for the use of ESD, as compared with EMR. Dr. Silvio de Melo discusses his preferred EMR technique and its many advantages in the management of BE, including for residual or refractory areas. In contrast, Dr. Mohamed Othman reviews the power of ESD and when we should consider this approach over EMR. We hope these discussions will facilitate your care for patients with Barrett’s esophagus.

We also welcome your thoughts on this topic — join the conversation on X at @AGA_GIHN. 

Gyanprakash A. Ketwaroo, MD, MSc, is associate professor of medicine, Yale University, New Haven, and chief of endoscopy at West Haven VA Medical Center, both in Connecticut. He is an associate editor for GI & Hepatology News.

Endoscopic Mucosal Resection: The ‘Workhorse’ for Patient Care

BY SILVIO W. DE MELO JR, MD, AGAF

Barrett’s esophagus (BE) remains an important clinical problem, being one of the modifiable risk factors for esophageal adenocarcinoma. The care for BE is complex and requires several steps to correctly formulate a therapeutic plan. It starts with a proper endoscopic examination. It is recommended to spend at least 1 minute inspecting and evaluating every centimeter of the salmon-colored epithelium, looking for change in vascular pattern, erosions/ulcers, nodules, and/or masses. After the inspection, random biopsies every 1-2 cm plus targeted biopsies will guide you. It is still controversial if the addition of other sampling strategies, such as brushings or confocal endomicroscopy, is needed.

The introduction of radiofrequency ablation (RFA) was paramount in popularizing the treatment options for BE and sunsetting the previous dominant modality, photodynamic therapy (PDT). RFA proved to have a superior clinical efficacy in replacing the intestinal metaplasia/BE with neosquamous epithelium while boosting a much better safety profile, compared with PDT. However, RFA is most efficacious for “flat BE” and it is not an effective, nor recommended, method to treat nodular BE or early cancer, such as carcinoma in situ or nodular high-grade dysplasia. Endoscopic mucosal resection (EMR) is utilized to overcome those limitations.

There are several techniques utilized for EMR:

• The lift and snare technique.
• The snare-in-cap technique.
• The Band-snare technique.

The free-hand submucosal lift and snare is not frequently used in the esophagus. It is difficult to maintain visualization while being confident that one has the whole lesion inside the snare and that the distal (anal side) part of the lesion is free of any unwanted tissue (to minimize complications such as perforations or unwelcomed gastric resections). It is difficult after the first resection to lift an adjacent area, as the fluid easily leaks from the first resected spot, thus removing larger lesions in piece-meal fashion is challenging. This technique can be used in small (in my personal experience, less than 5 mm) lesions, but, given that there are better and safer alternatives, I almost never use this technique for my esophageal EMR cases. I prefer to use the band-snare technique even for lesions under 5 mm.

The snare-in-cap technique has been utilized in the esophagus. In this technique, a cap is attached to the distal end of the scope and the size of the resection is determined by the size of the cap, usually under 1.5 cm. Because of the risk of perforation without previous lifting, it is required that the lesion is lifted with a submucosal fluid, saline or any Food and Drug Administration–approved EMR solution. The lesion is then suctioned inside the cap where the snare had been previously opened inside the cap, the snare is closed, and the tissue is resected. The same limitations regarding the inability to remove larger lesions (greater than 1.5 cm) because of the challenge in lifting the adjacent area applies here. However, the perforation risk for this technique is higher than the traditional lift and the band and snare techniques. Thus, this technique has fallen out of favor for most endoscopists.

The third technique (band-snare EMR) is the one that most endoscopists use for endoscopic mucosal resection. It is a small variation of the already time-tested and very familiar procedure of esophageal variceal band ligation (EVL). There are multiple commercially available kits for esophageal EMR. The kit contains the chamber with the bands and a proprietary hexagonal snare used to resect the specimen.

The advantages of this technique are:

• It is widely commercially available.
• It builds on a familiar procedure, EVL, therefore the learning curve is short.
• The set-up is quick and the procedure can be completed safely and effectively.
• There is no need for injecting the submucosal with a lifting solution.
• Despite the band having a size limitation of 1 cm, one can remove larger lesions by repeating the band and resect process, using the rosette technique.

Band-snare EMR also has limitations:

• There are only six bands on each chamber. Depending on the size of the lesion, one may need to use multiple kits.
• It is not suitable for en bloc resection of lesions greater than 1 cm.

My experience with band EMR is that we can complete the procedure in under 1 hour. The dreaded complication of perforation occurs in under 1% of cases, most bleeding episodes can easily be controlled endoscopically, and the risk of post-EMR stricture is minimal. Therefore, band EMR is the most used technique for esophageal endoscopic resections.

Esophageal EMR is also effective for other indications in BE therapy, such as residual and recurrent BE. Band-snare EMR can be used for an en bloc resection or rosette technique for the areas resistant to ablation therapies with great success and safety.

From a financial standpoint, comparing EMR with endoscopic submucosal dissection (ESD), EMR is the superior strategy given that EMR is widely available, has a much shorter learning curve, has a greater safety profile, is applicable to a wider variety of indications, and has a more favorable return on investment. EMR should be the workhorse for the care of patients with BE, reserving ESD for specific indications.

In summary, there is no “one-size-fits-all” endoscopic therapy in the care of BE. Most Barrett’s patients can be successfully treated with a combination of ablation plus EMR, reserving ESD for select cases.

Dr. de Melo is section chief of gastroenterology at the Orlando VA Healthcare System, Orlando, Florida. He declares no conflicts of interest.

ESD Over EMR for Resecting Esophageal Lesions

BY MOHAMED O. OTHMAN, MD, AGAF

Although endoscopic submucosal dissection (ESD) is the preferred endoscopic resection method in the East, the adoption of this technique in the West, particularly in the United States, has faced many hurdles. Many endoscopists who routinely perform piecemeal endoscopic mucosal resection (EMR) question the utility of ESD, arguing that EMR is just as effective. While this may hold true in certain situations, the global trend in the endoscopic treatment of early esophageal squamous cell carcinoma, nodular Barrett’s esophagus (BE), and early esophageal adenocarcinoma (EAC) has clearly shifted toward ESD. In this perspective, I will summarize why ESD is preferred over EMR for these indications and explore why ESD has yet to gain widespread adoption in the United States.

The superiority of ESD over EMR has been well established in multiple publications from both Eastern and Western literature. Mejia-Perez et al, in a multicenter cohort study from eight centers in North America, compared outcomes of ESD vs EMR for BE with high-grade dysplasia (HGD) or T1a adenocarcinoma in 243 patients. ESD achieved significantly higher en bloc resection rates (89% vs 43%) and R0 resection rates (73% vs 56%), compared with EMR, along with a substantially lower recurrence/residual disease rate on follow-up (3.5% in the ESD group vs 31.4% in EMR group). Additionally, more patients required repeat endoscopic resection after EMR to treat residual or recurrent disease (EMR, 24.2% vs ESD, 3.5%; P < .001).

Han et al conducted a meta-analysis of 22 studies comparing ESD and EMR for early esophageal neoplasia, including both squamous cell carcinoma (SCC) and BE-associated lesions. ESD was associated with significantly higher curative resection rates than EMR (OR, 9.74; 95% CI, 4.83-19.62; P < .0001). Of note, lesion size was a critical factor in determining the advantage of ESD. For lesions ≤ 10 mm, curative resection rates were comparable between ESD and EMR. However, for lesions > 10 mm, ESD achieved significantly higher curative resection rates. This size-based recommendation has been adopted by the American Society of Gastrointestinal Endoscopy (ASGE) in their recent guidelines on ESD indications for esophageal lesions. ASGE guidelines favors ESD over EMR for SCC lesions > 15 mm and for nodular BE with dysplasia or early EAC > 20 mm.

ESD is particularly beneficial in patients who develop early adenocarcinoma after RFA or EMR. Mesureur et al evaluated the efficacy of salvage ESD for Barrett’s recurrence or residual BE following RFA. In their multicenter retrospective study of 56 patients, salvage ESD achieved an en bloc resection rate of 89.3%, despite significant fibrosis, with an R0 resection rate of 66%. At a median follow-up of 14 months, most patients remained in endoscopic remission without the need for esophagectomy.

Combining ESD with RFA has also been shown to accelerate the eradication of BE with dysplasia while reducing the number of required sessions. Our group demonstrated the high efficacy of ESD followed by RFA in 18 patients, most of whom had long-segment BE with HGD or EAC. On average, patients required only one to two RFA sessions after ESD to achieve complete eradication of intestinal metaplasia (CE-IM). Over a median follow-up of 42.5 months (IQR, 28-59.25), complete eradication of early esophageal cancer was achieved in 13 patients (100%), eradication of dysplasia in 15 patients (100%), and CE-IM in 14 patients (77.8%).

Despite the overwhelming evidence supporting ESD and the strong endorsement from professional societies, adoption in the West continues to lag. Several factors contribute to this gap. First, ESD has a steep learning curve. Our data showed that, on average, an untutored practitioner achieved competency after 150-250 procedures, a finding corroborated by other US groups.

Second, there is no specific CPT code for ESD in the United States. Physicians are forced to bill the procedure as EMR or use an unlisted code, resulting in reimbursement that does not reflect the time and complexity of the procedure. Our group showed that physician reimbursement for ESD is highly variable, ranging from $50 to $800 per case, depending on insurance type.

Third, the increasing emphasis on productivity and RVU generation in academic settings has hindered the growth of ESD training in many institutions. Still, the outlook for ESD in the United States remains encouraging. Multiple industry-sponsored training courses are held annually, and professional societies are investing heavily in expanding access to structured education in ESD. Industry is also innovating devices that improve procedural efficiency and safety. Adopting novel approaches, such as traction-assisted ESD, has made the technique more appealing to endoscopists concerned about long procedure times. For example, our group proposed a standardized esophageal ESD technique that incorporates specimen self-retraction. This method improves both safety and speed and has helped address several procedural challenges. We’ve demonstrated that consistency in technique can substantially expedite esophageal ESD.

Fast forward 5 years: We anticipate a dedicated CPT code for ESD, broader access to advanced resection tools, and an expanding number of fellowships offering structured ESD training. These developments are poised to eliminate many of the current barriers. In summary, with robust data supporting the efficacy of ESD in early esophageal cancer, the focus in the United States should shift toward mastering and integrating the technique, rather than dismissing it in favor of piecemeal EMR.

Dr. Othman is chief of the gastroenterology and hepatology section at Baylor College of Medicine and Medicine Subspecialities Service Line Chief at Baylor St Luke’s Medical Center, both in Houston. He declares no conflicts of interest.

SAN DIEGO – Patients carrying at least one of the four key genes show a significantly increased risk for disease recurrence and mortality in gastric cancer, according to new research that potentially paves the way for precision oncology and improved targeting of therapies.

“About a third of patients with gastric cancer in our study had somatic mutations or variants of uncertain significance in [one of] four key genes,” lead author Ulysses Ribeiro, MD, PhD, a professor of digestive system surgery at the University of São Paulo School of Medicine in São Paulo, Brazil, said in a press briefing for the study, presented at Digestive Disease Week® (DDW) 2025.

“These patients were more likely to have their cancer come back or to die from the disease, even after surgery and the best chemotherapy and immunotherapy regimens,” said Ribeiro. While treatment strategies in gastric cancer have improved in recent years, resistance to multiple drugs continues, and the 5-year overall survival rate remains low — about 36% — underscoring the critical need for targeted therapies.

In an effort to identify genetic alterations that could have prognostic value, Ribeiro and his colleagues used next-generation DNA sequencing to analyze 21 genes in the tumor samples of 87 patients with gastric cancer who had undergone curative surgery and chemotherapy at the Sao Paulo Cancer Institute, São Paulo, Brazil.

Using Cox regression analysis, they found pathogenic variants or variants of uncertain significance in the following four genes: BRCA2, CDH1, RHOA, and TP53. “We found that 33% of patients carried at least one of these four genes,” Ribeiro told GI & Hepatology News.

Individually, each of the four genes with pathogenic variants or variants of uncertain significance had significantly or near-significantly higher risks in a survival analysis vs wild-type or benign variants, including BRCA2 (hazard ratio [HR], 4.33; P = .030); CDH1 (HR, 7.54; P = .004); RHOA (HR, 29.24; P < .001); and TP53 (HR, 2.82; P = .07).

A further multivariate analysis adjusting for key confounders showed that, when combined, carriers of the genes had lower disease-free survival (P = .005) and worse overall survival (P = .009) than those with none of the mutations.

“Individually, all four genes were related to prognosis in our gastric cancer patients, and when combined, the genes had even a higher difference in prognosis, varying from 2 to 28 times higher,” Ribeiro said.

Overall, factors such as having a more advanced tumor, node, metastasis stage, pathological stage, and the presence of a pathogenic mutation or a variant of uncertain significance in the four genes in the model were independently associated with worse disease-free survival.

 

Familiar Genes

Some of these genes are highly familiar. BRCA2 is well-known for its role in increasing the risk for breast and ovarian cancers, and CDH1 is known to be associated with hereditary diffuse gastric cancer, which is the most common hereditary cancer syndrome linked to gastric cancer.

TP53, also known as the “guardian of the genome,” is the most commonly altered gene in human cancers, while RHOA is known to be involved in encoding the GTPase protein RhoA, which is key in the regulation of cell shape, motility, and other essential cellular processes.

“This is the first time that these four genes have been shown to strongly relate to these gastric cancer outcomes,” said Ribeiro. This suggests that there’s more than one pathway by which stomach cancer forms and that some stomach cancers are much more aggressive than others.

He noted that “patients without these high-risk mutations” could be given “less aggressive treatment, in some cases sparing them from unnecessary side effects.”

Speaking during the press briefing, Loren A. Laine, MD, AGAF, who is a professor of medicine and chief of the Section of Digestive Diseases at the Yale School of Medicine in New Haven, Connecticut, and council chair of DDW 2025, agreed that “certainly, if these genetic factors, along with other factors, predict risk, this also has implications in practice with respect to the level of monitoring during the follow-up and determining the need for therapy.”

In addition, “it will be interesting to see how much this adds to other known risk factors, such as pathologic stage,” said Laine.

A strength of this study, “which I think is unique, is that it looks at a Western population,” whereas data on gastric as well as esophageal cancer is heavily biased to Eastern regions like China and East Asia, where the rates are much higher than in the West, Alia Qureshi, MD, an associate professor of esophageal and gastric cancer surgery at Oregon Health & Science University in Portland, Oregon, told GI & Hepatology News.

While noting the limitation of the relatively small sample size, Qureshi said the study is nevertheless “exciting and moving the direction we want to go, specifically towards precision medicine [and] precision oncology.”

The study “builds on existing understanding, especially with regard to TP53 and CDH1, and it points to the opportunity to use this data in a way to direct patient care or possibly therapeutic intervention,” she said.

Laine’s disclosures include consulting and/or relationships with Medtronic, Phathom Pharmaceuticals, Biohaven, Celgene, Intercept Pharmaceuticals, Merck, and Pfizer. Qureshi had no disclosures to report.

A version of this article appeared on Medscape.com.

SAN DIEGO – Patients carrying at least one of the four key genes show a significantly increased risk for disease recurrence and mortality in gastric cancer, according to new research that potentially paves the way for precision oncology and improved targeting of therapies.

“About a third of patients with gastric cancer in our study had somatic mutations or variants of uncertain significance in [one of] four key genes,” lead author Ulysses Ribeiro, MD, PhD, a professor of digestive system surgery at the University of São Paulo School of Medicine in São Paulo, Brazil, said in a press briefing for the study, presented at Digestive Disease Week® (DDW) 2025.

“These patients were more likely to have their cancer come back or to die from the disease, even after surgery and the best chemotherapy and immunotherapy regimens,” said Ribeiro. While treatment strategies in gastric cancer have improved in recent years, resistance to multiple drugs continues, and the 5-year overall survival rate remains low — about 36% — underscoring the critical need for targeted therapies.

In an effort to identify genetic alterations that could have prognostic value, Ribeiro and his colleagues used next-generation DNA sequencing to analyze 21 genes in the tumor samples of 87 patients with gastric cancer who had undergone curative surgery and chemotherapy at the Sao Paulo Cancer Institute, São Paulo, Brazil.

Using Cox regression analysis, they found pathogenic variants or variants of uncertain significance in the following four genes: BRCA2, CDH1, RHOA, and TP53. “We found that 33% of patients carried at least one of these four genes,” Ribeiro told GI & Hepatology News.

Individually, each of the four genes with pathogenic variants or variants of uncertain significance had significantly or near-significantly higher risks in a survival analysis vs wild-type or benign variants, including BRCA2 (hazard ratio [HR], 4.33; P = .030); CDH1 (HR, 7.54; P = .004); RHOA (HR, 29.24; P < .001); and TP53 (HR, 2.82; P = .07).

A further multivariate analysis adjusting for key confounders showed that, when combined, carriers of the genes had lower disease-free survival (P = .005) and worse overall survival (P = .009) than those with none of the mutations.

“Individually, all four genes were related to prognosis in our gastric cancer patients, and when combined, the genes had even a higher difference in prognosis, varying from 2 to 28 times higher,” Ribeiro said.

Overall, factors such as having a more advanced tumor, node, metastasis stage, pathological stage, and the presence of a pathogenic mutation or a variant of uncertain significance in the four genes in the model were independently associated with worse disease-free survival.

 

Familiar Genes

Some of these genes are highly familiar. BRCA2 is well-known for its role in increasing the risk for breast and ovarian cancers, and CDH1 is known to be associated with hereditary diffuse gastric cancer, which is the most common hereditary cancer syndrome linked to gastric cancer.

TP53, also known as the “guardian of the genome,” is the most commonly altered gene in human cancers, while RHOA is known to be involved in encoding the GTPase protein RhoA, which is key in the regulation of cell shape, motility, and other essential cellular processes.

“This is the first time that these four genes have been shown to strongly relate to these gastric cancer outcomes,” said Ribeiro. This suggests that there’s more than one pathway by which stomach cancer forms and that some stomach cancers are much more aggressive than others.

He noted that “patients without these high-risk mutations” could be given “less aggressive treatment, in some cases sparing them from unnecessary side effects.”

Speaking during the press briefing, Loren A. Laine, MD, AGAF, who is a professor of medicine and chief of the Section of Digestive Diseases at the Yale School of Medicine in New Haven, Connecticut, and council chair of DDW 2025, agreed that “certainly, if these genetic factors, along with other factors, predict risk, this also has implications in practice with respect to the level of monitoring during the follow-up and determining the need for therapy.”

In addition, “it will be interesting to see how much this adds to other known risk factors, such as pathologic stage,” said Laine.

A strength of this study, “which I think is unique, is that it looks at a Western population,” whereas data on gastric as well as esophageal cancer is heavily biased to Eastern regions like China and East Asia, where the rates are much higher than in the West, Alia Qureshi, MD, an associate professor of esophageal and gastric cancer surgery at Oregon Health & Science University in Portland, Oregon, told GI & Hepatology News.

While noting the limitation of the relatively small sample size, Qureshi said the study is nevertheless “exciting and moving the direction we want to go, specifically towards precision medicine [and] precision oncology.”

The study “builds on existing understanding, especially with regard to TP53 and CDH1, and it points to the opportunity to use this data in a way to direct patient care or possibly therapeutic intervention,” she said.

Laine’s disclosures include consulting and/or relationships with Medtronic, Phathom Pharmaceuticals, Biohaven, Celgene, Intercept Pharmaceuticals, Merck, and Pfizer. Qureshi had no disclosures to report.

A version of this article appeared on Medscape.com.

SAN DIEGO – Patients carrying at least one of the four key genes show a significantly increased risk for disease recurrence and mortality in gastric cancer, according to new research that potentially paves the way for precision oncology and improved targeting of therapies.

“About a third of patients with gastric cancer in our study had somatic mutations or variants of uncertain significance in [one of] four key genes,” lead author Ulysses Ribeiro, MD, PhD, a professor of digestive system surgery at the University of São Paulo School of Medicine in São Paulo, Brazil, said in a press briefing for the study, presented at Digestive Disease Week® (DDW) 2025.

“These patients were more likely to have their cancer come back or to die from the disease, even after surgery and the best chemotherapy and immunotherapy regimens,” said Ribeiro. While treatment strategies in gastric cancer have improved in recent years, resistance to multiple drugs continues, and the 5-year overall survival rate remains low — about 36% — underscoring the critical need for targeted therapies.

In an effort to identify genetic alterations that could have prognostic value, Ribeiro and his colleagues used next-generation DNA sequencing to analyze 21 genes in the tumor samples of 87 patients with gastric cancer who had undergone curative surgery and chemotherapy at the Sao Paulo Cancer Institute, São Paulo, Brazil.

Using Cox regression analysis, they found pathogenic variants or variants of uncertain significance in the following four genes: BRCA2, CDH1, RHOA, and TP53. “We found that 33% of patients carried at least one of these four genes,” Ribeiro told GI & Hepatology News.

Individually, each of the four genes with pathogenic variants or variants of uncertain significance had significantly or near-significantly higher risks in a survival analysis vs wild-type or benign variants, including BRCA2 (hazard ratio [HR], 4.33; P = .030); CDH1 (HR, 7.54; P = .004); RHOA (HR, 29.24; P < .001); and TP53 (HR, 2.82; P = .07).

A further multivariate analysis adjusting for key confounders showed that, when combined, carriers of the genes had lower disease-free survival (P = .005) and worse overall survival (P = .009) than those with none of the mutations.

“Individually, all four genes were related to prognosis in our gastric cancer patients, and when combined, the genes had even a higher difference in prognosis, varying from 2 to 28 times higher,” Ribeiro said.

Overall, factors such as having a more advanced tumor, node, metastasis stage, pathological stage, and the presence of a pathogenic mutation or a variant of uncertain significance in the four genes in the model were independently associated with worse disease-free survival.

 

Familiar Genes

Some of these genes are highly familiar. BRCA2 is well-known for its role in increasing the risk for breast and ovarian cancers, and CDH1 is known to be associated with hereditary diffuse gastric cancer, which is the most common hereditary cancer syndrome linked to gastric cancer.

TP53, also known as the “guardian of the genome,” is the most commonly altered gene in human cancers, while RHOA is known to be involved in encoding the GTPase protein RhoA, which is key in the regulation of cell shape, motility, and other essential cellular processes.

“This is the first time that these four genes have been shown to strongly relate to these gastric cancer outcomes,” said Ribeiro. This suggests that there’s more than one pathway by which stomach cancer forms and that some stomach cancers are much more aggressive than others.

He noted that “patients without these high-risk mutations” could be given “less aggressive treatment, in some cases sparing them from unnecessary side effects.”

Speaking during the press briefing, Loren A. Laine, MD, AGAF, who is a professor of medicine and chief of the Section of Digestive Diseases at the Yale School of Medicine in New Haven, Connecticut, and council chair of DDW 2025, agreed that “certainly, if these genetic factors, along with other factors, predict risk, this also has implications in practice with respect to the level of monitoring during the follow-up and determining the need for therapy.”

In addition, “it will be interesting to see how much this adds to other known risk factors, such as pathologic stage,” said Laine.

A strength of this study, “which I think is unique, is that it looks at a Western population,” whereas data on gastric as well as esophageal cancer is heavily biased to Eastern regions like China and East Asia, where the rates are much higher than in the West, Alia Qureshi, MD, an associate professor of esophageal and gastric cancer surgery at Oregon Health & Science University in Portland, Oregon, told GI & Hepatology News.

While noting the limitation of the relatively small sample size, Qureshi said the study is nevertheless “exciting and moving the direction we want to go, specifically towards precision medicine [and] precision oncology.”

The study “builds on existing understanding, especially with regard to TP53 and CDH1, and it points to the opportunity to use this data in a way to direct patient care or possibly therapeutic intervention,” she said.

Laine’s disclosures include consulting and/or relationships with Medtronic, Phathom Pharmaceuticals, Biohaven, Celgene, Intercept Pharmaceuticals, Merck, and Pfizer. Qureshi had no disclosures to report.

A version of this article appeared on Medscape.com.

SAN DIEGO — A 20-year initiative by Kaiser Permanente Northern California that assessed colorectal cancer (CRC) screening status and offered flexible options for screening has made a huge difference in CRC incidence, deaths, and racial disparities, an analysis showed.

“The program promptly doubled the proportion of people up to date with screening,” reported lead investigator Douglas A. Corley, MD, PhD, AGAF, a research scientist with Kaiser’s Division of Research, at a press briefing held on April 24, ahead of a presentation at the Digestive Disease Week® (DDW) 2025.

Additionally, within about 10 years, cancer rates were cut by a third, deaths were halved for the second most common cause of cancer deaths in the United States, and the differences that had previously been seen by race or ethnicity were largely eliminated, he said.

“Ten years ago, there were big gaps in cancer risk and death, especially among our Black patients. Now, those differences are nearly gone,” Corley said.

 

Closing the Gap

A systematic CRC screening program was implemented across Kaiser Permanente Northern California. The program included proactive outreach to members who were overdue for screening and mailing them fecal immunochemical test (FIT) kits for at-home use.

Corley and colleagues tracked screening status and CRC incidence and mortality annually from 2000 to 2019 among about 1.1 million members aged 50-75 years across 22 medical centers of the integrated healthcare system. The cohort included American Indian or Alaska Native, Asian, Black, Hispanic, Native Hawaiian or Pacific Islander, and White members.

Screening rates via FIT, colonoscopy, or sigmoidoscopy more than doubled after starting the program, from about 37% in the early years to about 80% within a few years, and it stayed that high through 2019, Corley reported. 

“Importantly, these large increases occurred across the whole population with only small differences,” he said. 

For example, about 76% of Hispanic members, 77% of Black members, 82% of White members, and 83% of Asian members were up to date in the later years and through 2019.

“This shows that systematic, comparable outreach can provide a level playing field for completion of preventive care,” Corley said.

After an expected early uptick in CRC incidence due to early detection, incidence later declined and by 2019 had dropped approximately 30% across the groups.

 

Long-Standing Disparities Erased

CRC deaths also fell by about 50% across all groups, with the largest decline among Black members, Corley noted.

Racial and ethnic disparities in both CRC incidence and mortality have long existed, with Black patients in particular experiencing higher risks and worse outcomes, likely from a mixture of risk factors and healthcare utilization, Corley said.

Offering outreach and equal access to screening in the Kaiser program erased those long-standing disparities.

“It’s remarkable that some of these large differences in mortality by race and ethnicity that we saw two decades ago, and which are found throughout the United States, are now similar to small chance variation in the population,” Corley said.

Flexibility was key to getting more people screened, he noted. “It’s about reaching people at their homes and offering a choice to patients. It’s an astonishingly simple concept.”

It’s important to note that these findings stem from a large, integrated healthcare system, which may differ from other settings, although similar outreach strategies have succeeded in safety net clinics and smaller practices, Corley added.

By boosting screening rates to 80%, the health system reached the level that’s essentially been defined in the past as our goal of screening programs, said Loren Laine, MD, AGAF, professor of medicine (digestive diseases) at Yale School of Medicine, New Haven, Connecticut, and chair of this year’s DDW. 

“It shows that if health systems institute programmatic screening for all their covered individuals, they could markedly increase screening, said Laine, who also served as moderator of the press briefing.

“Most importantly, of course, [screening] was associated with a reduction in colorectal cancer incidence and deaths,” he said.

The study had no commercial funding. Corley reported having no relevant conflicts of interest.

Laine’s disclosures included consulting and/or relationships with Medtronic, Phathom Pharmaceuticals, Biohaven, Celgene, Intercept, Merck, and Pfizer.

A version of this article appeared on Medscape.com.

SAN DIEGO — A 20-year initiative by Kaiser Permanente Northern California that assessed colorectal cancer (CRC) screening status and offered flexible options for screening has made a huge difference in CRC incidence, deaths, and racial disparities, an analysis showed.

“The program promptly doubled the proportion of people up to date with screening,” reported lead investigator Douglas A. Corley, MD, PhD, AGAF, a research scientist with Kaiser’s Division of Research, at a press briefing held on April 24, ahead of a presentation at the Digestive Disease Week® (DDW) 2025.

Additionally, within about 10 years, cancer rates were cut by a third, deaths were halved for the second most common cause of cancer deaths in the United States, and the differences that had previously been seen by race or ethnicity were largely eliminated, he said.

“Ten years ago, there were big gaps in cancer risk and death, especially among our Black patients. Now, those differences are nearly gone,” Corley said.

 

Closing the Gap

A systematic CRC screening program was implemented across Kaiser Permanente Northern California. The program included proactive outreach to members who were overdue for screening and mailing them fecal immunochemical test (FIT) kits for at-home use.

Corley and colleagues tracked screening status and CRC incidence and mortality annually from 2000 to 2019 among about 1.1 million members aged 50-75 years across 22 medical centers of the integrated healthcare system. The cohort included American Indian or Alaska Native, Asian, Black, Hispanic, Native Hawaiian or Pacific Islander, and White members.

Screening rates via FIT, colonoscopy, or sigmoidoscopy more than doubled after starting the program, from about 37% in the early years to about 80% within a few years, and it stayed that high through 2019, Corley reported. 

“Importantly, these large increases occurred across the whole population with only small differences,” he said. 

For example, about 76% of Hispanic members, 77% of Black members, 82% of White members, and 83% of Asian members were up to date in the later years and through 2019.

“This shows that systematic, comparable outreach can provide a level playing field for completion of preventive care,” Corley said.

After an expected early uptick in CRC incidence due to early detection, incidence later declined and by 2019 had dropped approximately 30% across the groups.

 

Long-Standing Disparities Erased

CRC deaths also fell by about 50% across all groups, with the largest decline among Black members, Corley noted.

Racial and ethnic disparities in both CRC incidence and mortality have long existed, with Black patients in particular experiencing higher risks and worse outcomes, likely from a mixture of risk factors and healthcare utilization, Corley said.

Offering outreach and equal access to screening in the Kaiser program erased those long-standing disparities.

“It’s remarkable that some of these large differences in mortality by race and ethnicity that we saw two decades ago, and which are found throughout the United States, are now similar to small chance variation in the population,” Corley said.

Flexibility was key to getting more people screened, he noted. “It’s about reaching people at their homes and offering a choice to patients. It’s an astonishingly simple concept.”

It’s important to note that these findings stem from a large, integrated healthcare system, which may differ from other settings, although similar outreach strategies have succeeded in safety net clinics and smaller practices, Corley added.

By boosting screening rates to 80%, the health system reached the level that’s essentially been defined in the past as our goal of screening programs, said Loren Laine, MD, AGAF, professor of medicine (digestive diseases) at Yale School of Medicine, New Haven, Connecticut, and chair of this year’s DDW. 

“It shows that if health systems institute programmatic screening for all their covered individuals, they could markedly increase screening, said Laine, who also served as moderator of the press briefing.

“Most importantly, of course, [screening] was associated with a reduction in colorectal cancer incidence and deaths,” he said.

The study had no commercial funding. Corley reported having no relevant conflicts of interest.

Laine’s disclosures included consulting and/or relationships with Medtronic, Phathom Pharmaceuticals, Biohaven, Celgene, Intercept, Merck, and Pfizer.

A version of this article appeared on Medscape.com.

SAN DIEGO — A 20-year initiative by Kaiser Permanente Northern California that assessed colorectal cancer (CRC) screening status and offered flexible options for screening has made a huge difference in CRC incidence, deaths, and racial disparities, an analysis showed.

“The program promptly doubled the proportion of people up to date with screening,” reported lead investigator Douglas A. Corley, MD, PhD, AGAF, a research scientist with Kaiser’s Division of Research, at a press briefing held on April 24, ahead of a presentation at the Digestive Disease Week® (DDW) 2025.

Additionally, within about 10 years, cancer rates were cut by a third, deaths were halved for the second most common cause of cancer deaths in the United States, and the differences that had previously been seen by race or ethnicity were largely eliminated, he said.

“Ten years ago, there were big gaps in cancer risk and death, especially among our Black patients. Now, those differences are nearly gone,” Corley said.

 

Closing the Gap

A systematic CRC screening program was implemented across Kaiser Permanente Northern California. The program included proactive outreach to members who were overdue for screening and mailing them fecal immunochemical test (FIT) kits for at-home use.

Corley and colleagues tracked screening status and CRC incidence and mortality annually from 2000 to 2019 among about 1.1 million members aged 50-75 years across 22 medical centers of the integrated healthcare system. The cohort included American Indian or Alaska Native, Asian, Black, Hispanic, Native Hawaiian or Pacific Islander, and White members.

Screening rates via FIT, colonoscopy, or sigmoidoscopy more than doubled after starting the program, from about 37% in the early years to about 80% within a few years, and it stayed that high through 2019, Corley reported. 

“Importantly, these large increases occurred across the whole population with only small differences,” he said. 

For example, about 76% of Hispanic members, 77% of Black members, 82% of White members, and 83% of Asian members were up to date in the later years and through 2019.

“This shows that systematic, comparable outreach can provide a level playing field for completion of preventive care,” Corley said.

After an expected early uptick in CRC incidence due to early detection, incidence later declined and by 2019 had dropped approximately 30% across the groups.

 

Long-Standing Disparities Erased

CRC deaths also fell by about 50% across all groups, with the largest decline among Black members, Corley noted.

Racial and ethnic disparities in both CRC incidence and mortality have long existed, with Black patients in particular experiencing higher risks and worse outcomes, likely from a mixture of risk factors and healthcare utilization, Corley said.

Offering outreach and equal access to screening in the Kaiser program erased those long-standing disparities.

“It’s remarkable that some of these large differences in mortality by race and ethnicity that we saw two decades ago, and which are found throughout the United States, are now similar to small chance variation in the population,” Corley said.

Flexibility was key to getting more people screened, he noted. “It’s about reaching people at their homes and offering a choice to patients. It’s an astonishingly simple concept.”

It’s important to note that these findings stem from a large, integrated healthcare system, which may differ from other settings, although similar outreach strategies have succeeded in safety net clinics and smaller practices, Corley added.

By boosting screening rates to 80%, the health system reached the level that’s essentially been defined in the past as our goal of screening programs, said Loren Laine, MD, AGAF, professor of medicine (digestive diseases) at Yale School of Medicine, New Haven, Connecticut, and chair of this year’s DDW. 

“It shows that if health systems institute programmatic screening for all their covered individuals, they could markedly increase screening, said Laine, who also served as moderator of the press briefing.

“Most importantly, of course, [screening] was associated with a reduction in colorectal cancer incidence and deaths,” he said.

The study had no commercial funding. Corley reported having no relevant conflicts of interest.

Laine’s disclosures included consulting and/or relationships with Medtronic, Phathom Pharmaceuticals, Biohaven, Celgene, Intercept, Merck, and Pfizer.

A version of this article appeared on Medscape.com.

An AGA multidisciplinary panel has reached the conclusion that no recommendation can be made for or against the use of computer-aided detection (CADe)–assisted colonoscopy for colorectal cancer (CRC), the third most common cause of cancer mortality in the United States.

The systematic data review is a collaboration between AGA and The BMJ’s MAGIC Rapid Recommendations. The BMJ issued a separate recommendation against CADe shortly after the AGA guideline was published.

Led by Shahnaz S. Sultan, MD, MHSc, AGAF, of the Division of Gastroenterology, Hepatology, and Nutrition at University of Minnesota, Minneapolis, and recently published in Gastroenterology, found only very low certainty of GRADE-based evidence for several critical long-term outcomes, both desirable and undesirable. These included the following: 11 fewer CRCs per 10,000 individuals and two fewer CRC deaths per 10,000 individuals, an increased burden of more intensive surveillance colonoscopies (635 more per 10,000 individuals), and cost and resource implications.

This technology did, however, yield an 8% (95% CI, 6-10) absolute increase in the adenoma detection rate (ADR) and a 2% (95% CI, 0-4) increase in the detection rate of advanced adenomas and/or sessile serrated lesions. “How this translates into a reduction in CRC incidence or death is where we were uncertain,” Sultan said. “Our best effort at trying to translate the ADR and other endoscopy outcomes to CRC incidence and CRC death relied on the modeling study, which included a lot of assumptions, which also contributed to our overall lower certainty.”

The systematic and meta-analysis included 41 randomized controlled trials with more than 32,108 participants who underwent CADe-assisted colonoscopy. This technology was associated with a higher polyp detection rate than standard colonoscopy: 56.1% vs 47.9% (relative risk [RR], 1.22, 95% CI, 1.15-1.28). It also had a higher ADR: 44.8% vs 37.4% (RR, 1.22; 95% CI, 1.16-1.29).

But although CADe-assisted colonoscopy may increase ADR, it carries a risk for overdiagnosis, as most polyps detected during colonoscopy are diminutive (< 5 mm) and of low malignant potential, the panel noted. Approximately 25% of lesions are missed at colonoscopy. More than 15 million colonoscopies are performed annually in the United States, but studies have demonstrated variable quality of colonoscopies across key quality indicators.

“Artificial intelligence [AI] is revolutionizing medicine and healthcare in the field of GI [gastroenterology], and CADe in colonoscopy has been brought to commercialization,” Sultan told GI & Hepatology News. “Unlike many areas of endoscopic research where we often have a finite number of clinical trial data, CADe-assisted colonoscopy intervention has been studied in over 44 randomized controlled trials and numerous nonrandomized, real-world studies. The question of whether or not to adopt this intervention at a health system or practice level is an important question that was prioritized to be addressed as guidance was needed.”

Commenting on the guideline but not involved in its formulation, Larry S. Kim, MD, MBA, AGAF, a gastroenterologist at South Denver Gastroenterology in Denver, Colorado, said his practice group has used the GI Genius AI system in its affiliated hospitals but has so far chosen not to implement the technology at its endoscopy centers. “At the hospital, our physicians have the ability to utilize the system for select patients or not at all,” he told GI & Hepatology News.

The fact that The BMJ reached a different conclusion based on the same data, evidence-grading system, and microsimulation, Kim added, “highlights the point that when evidence for benefit is uncertain, underlying values are critical.” In declining to make a recommendation, the AGA panel balanced the benefit of improved detection of potentially precancerous adenomas vs increased resource utilization in the face of unclear benefit. “With different priorities, other bodies could reasonably decide to recommend either for or against CADe.”

 

The Future

According to Sultan, gastroenterologists need a better understanding of patient values and preferences and the value placed on increased adenoma detection, which may also lead to more lifetime colonoscopies without reducing the risk for CRC. “We need better intermediate- and long-term data on the impact of adenoma detection on interval cancers and CRC incidence,” she said. “We need data on detection of polyps that are more clinically significant such as those 6-10 mm in size, as well as serrated sessile lesions. We also need to understand at the population or health system level what the impact is on resources, cost, and access.”

Ultimately, the living guideline underscores the trade-off between desirable and undesirable effects and the limitations of current evidence to support a recommendation, but CADe has to improve as an iterative AI application with further validation and better training.

With the anticipated improvement in software accuracy as AI machine learning reads increasing numbers of images, Sultan added, “the next version of the software may perform better, especially for polyps that are more clinically significant or for flat sessile serrated polyps, which are harder to detect. We plan to revisit the question in the next year or two and potentially revise the guideline.”

These guidelines were fully funded by the AGA Institute with no funding from any outside agency or industry.

Sultan is supported by the US Food and Drug Administration. Co-authors Shazia Mehmood Siddique, Dennis L. Shung, and Benjamin Lebwohl are supported by grants from the National Institute of Diabetes and Digestive and Kidney Diseases. Theodore R. Levin is supported by the Permanente Medical Group Delivery Science and Applied Research Program. Cesare Hassan is a consultant for Fujifilm and Olympus. Peter S. Liang reported doing research work for Freenome and advisory board work for Guardant Health and Natera.

Kim is the AGA president-elect. He disclosed no competing interests relevant to his comments.

A version of this article appeared on Medscape.com.

An AGA multidisciplinary panel has reached the conclusion that no recommendation can be made for or against the use of computer-aided detection (CADe)–assisted colonoscopy for colorectal cancer (CRC), the third most common cause of cancer mortality in the United States.

The systematic data review is a collaboration between AGA and The BMJ’s MAGIC Rapid Recommendations. The BMJ issued a separate recommendation against CADe shortly after the AGA guideline was published.

Led by Shahnaz S. Sultan, MD, MHSc, AGAF, of the Division of Gastroenterology, Hepatology, and Nutrition at University of Minnesota, Minneapolis, and recently published in Gastroenterology, found only very low certainty of GRADE-based evidence for several critical long-term outcomes, both desirable and undesirable. These included the following: 11 fewer CRCs per 10,000 individuals and two fewer CRC deaths per 10,000 individuals, an increased burden of more intensive surveillance colonoscopies (635 more per 10,000 individuals), and cost and resource implications.

This technology did, however, yield an 8% (95% CI, 6-10) absolute increase in the adenoma detection rate (ADR) and a 2% (95% CI, 0-4) increase in the detection rate of advanced adenomas and/or sessile serrated lesions. “How this translates into a reduction in CRC incidence or death is where we were uncertain,” Sultan said. “Our best effort at trying to translate the ADR and other endoscopy outcomes to CRC incidence and CRC death relied on the modeling study, which included a lot of assumptions, which also contributed to our overall lower certainty.”

The systematic and meta-analysis included 41 randomized controlled trials with more than 32,108 participants who underwent CADe-assisted colonoscopy. This technology was associated with a higher polyp detection rate than standard colonoscopy: 56.1% vs 47.9% (relative risk [RR], 1.22, 95% CI, 1.15-1.28). It also had a higher ADR: 44.8% vs 37.4% (RR, 1.22; 95% CI, 1.16-1.29).

But although CADe-assisted colonoscopy may increase ADR, it carries a risk for overdiagnosis, as most polyps detected during colonoscopy are diminutive (< 5 mm) and of low malignant potential, the panel noted. Approximately 25% of lesions are missed at colonoscopy. More than 15 million colonoscopies are performed annually in the United States, but studies have demonstrated variable quality of colonoscopies across key quality indicators.

“Artificial intelligence [AI] is revolutionizing medicine and healthcare in the field of GI [gastroenterology], and CADe in colonoscopy has been brought to commercialization,” Sultan told GI & Hepatology News. “Unlike many areas of endoscopic research where we often have a finite number of clinical trial data, CADe-assisted colonoscopy intervention has been studied in over 44 randomized controlled trials and numerous nonrandomized, real-world studies. The question of whether or not to adopt this intervention at a health system or practice level is an important question that was prioritized to be addressed as guidance was needed.”

Commenting on the guideline but not involved in its formulation, Larry S. Kim, MD, MBA, AGAF, a gastroenterologist at South Denver Gastroenterology in Denver, Colorado, said his practice group has used the GI Genius AI system in its affiliated hospitals but has so far chosen not to implement the technology at its endoscopy centers. “At the hospital, our physicians have the ability to utilize the system for select patients or not at all,” he told GI & Hepatology News.

The fact that The BMJ reached a different conclusion based on the same data, evidence-grading system, and microsimulation, Kim added, “highlights the point that when evidence for benefit is uncertain, underlying values are critical.” In declining to make a recommendation, the AGA panel balanced the benefit of improved detection of potentially precancerous adenomas vs increased resource utilization in the face of unclear benefit. “With different priorities, other bodies could reasonably decide to recommend either for or against CADe.”

 

The Future

According to Sultan, gastroenterologists need a better understanding of patient values and preferences and the value placed on increased adenoma detection, which may also lead to more lifetime colonoscopies without reducing the risk for CRC. “We need better intermediate- and long-term data on the impact of adenoma detection on interval cancers and CRC incidence,” she said. “We need data on detection of polyps that are more clinically significant such as those 6-10 mm in size, as well as serrated sessile lesions. We also need to understand at the population or health system level what the impact is on resources, cost, and access.”

Ultimately, the living guideline underscores the trade-off between desirable and undesirable effects and the limitations of current evidence to support a recommendation, but CADe has to improve as an iterative AI application with further validation and better training.

With the anticipated improvement in software accuracy as AI machine learning reads increasing numbers of images, Sultan added, “the next version of the software may perform better, especially for polyps that are more clinically significant or for flat sessile serrated polyps, which are harder to detect. We plan to revisit the question in the next year or two and potentially revise the guideline.”

These guidelines were fully funded by the AGA Institute with no funding from any outside agency or industry.

Sultan is supported by the US Food and Drug Administration. Co-authors Shazia Mehmood Siddique, Dennis L. Shung, and Benjamin Lebwohl are supported by grants from the National Institute of Diabetes and Digestive and Kidney Diseases. Theodore R. Levin is supported by the Permanente Medical Group Delivery Science and Applied Research Program. Cesare Hassan is a consultant for Fujifilm and Olympus. Peter S. Liang reported doing research work for Freenome and advisory board work for Guardant Health and Natera.

Kim is the AGA president-elect. He disclosed no competing interests relevant to his comments.

A version of this article appeared on Medscape.com.

An AGA multidisciplinary panel has reached the conclusion that no recommendation can be made for or against the use of computer-aided detection (CADe)–assisted colonoscopy for colorectal cancer (CRC), the third most common cause of cancer mortality in the United States.

The systematic data review is a collaboration between AGA and The BMJ’s MAGIC Rapid Recommendations. The BMJ issued a separate recommendation against CADe shortly after the AGA guideline was published.

Led by Shahnaz S. Sultan, MD, MHSc, AGAF, of the Division of Gastroenterology, Hepatology, and Nutrition at University of Minnesota, Minneapolis, and recently published in Gastroenterology, found only very low certainty of GRADE-based evidence for several critical long-term outcomes, both desirable and undesirable. These included the following: 11 fewer CRCs per 10,000 individuals and two fewer CRC deaths per 10,000 individuals, an increased burden of more intensive surveillance colonoscopies (635 more per 10,000 individuals), and cost and resource implications.

This technology did, however, yield an 8% (95% CI, 6-10) absolute increase in the adenoma detection rate (ADR) and a 2% (95% CI, 0-4) increase in the detection rate of advanced adenomas and/or sessile serrated lesions. “How this translates into a reduction in CRC incidence or death is where we were uncertain,” Sultan said. “Our best effort at trying to translate the ADR and other endoscopy outcomes to CRC incidence and CRC death relied on the modeling study, which included a lot of assumptions, which also contributed to our overall lower certainty.”

The systematic and meta-analysis included 41 randomized controlled trials with more than 32,108 participants who underwent CADe-assisted colonoscopy. This technology was associated with a higher polyp detection rate than standard colonoscopy: 56.1% vs 47.9% (relative risk [RR], 1.22, 95% CI, 1.15-1.28). It also had a higher ADR: 44.8% vs 37.4% (RR, 1.22; 95% CI, 1.16-1.29).

But although CADe-assisted colonoscopy may increase ADR, it carries a risk for overdiagnosis, as most polyps detected during colonoscopy are diminutive (< 5 mm) and of low malignant potential, the panel noted. Approximately 25% of lesions are missed at colonoscopy. More than 15 million colonoscopies are performed annually in the United States, but studies have demonstrated variable quality of colonoscopies across key quality indicators.

“Artificial intelligence [AI] is revolutionizing medicine and healthcare in the field of GI [gastroenterology], and CADe in colonoscopy has been brought to commercialization,” Sultan told GI & Hepatology News. “Unlike many areas of endoscopic research where we often have a finite number of clinical trial data, CADe-assisted colonoscopy intervention has been studied in over 44 randomized controlled trials and numerous nonrandomized, real-world studies. The question of whether or not to adopt this intervention at a health system or practice level is an important question that was prioritized to be addressed as guidance was needed.”

Commenting on the guideline but not involved in its formulation, Larry S. Kim, MD, MBA, AGAF, a gastroenterologist at South Denver Gastroenterology in Denver, Colorado, said his practice group has used the GI Genius AI system in its affiliated hospitals but has so far chosen not to implement the technology at its endoscopy centers. “At the hospital, our physicians have the ability to utilize the system for select patients or not at all,” he told GI & Hepatology News.

The fact that The BMJ reached a different conclusion based on the same data, evidence-grading system, and microsimulation, Kim added, “highlights the point that when evidence for benefit is uncertain, underlying values are critical.” In declining to make a recommendation, the AGA panel balanced the benefit of improved detection of potentially precancerous adenomas vs increased resource utilization in the face of unclear benefit. “With different priorities, other bodies could reasonably decide to recommend either for or against CADe.”

 

The Future

According to Sultan, gastroenterologists need a better understanding of patient values and preferences and the value placed on increased adenoma detection, which may also lead to more lifetime colonoscopies without reducing the risk for CRC. “We need better intermediate- and long-term data on the impact of adenoma detection on interval cancers and CRC incidence,” she said. “We need data on detection of polyps that are more clinically significant such as those 6-10 mm in size, as well as serrated sessile lesions. We also need to understand at the population or health system level what the impact is on resources, cost, and access.”

Ultimately, the living guideline underscores the trade-off between desirable and undesirable effects and the limitations of current evidence to support a recommendation, but CADe has to improve as an iterative AI application with further validation and better training.

With the anticipated improvement in software accuracy as AI machine learning reads increasing numbers of images, Sultan added, “the next version of the software may perform better, especially for polyps that are more clinically significant or for flat sessile serrated polyps, which are harder to detect. We plan to revisit the question in the next year or two and potentially revise the guideline.”

These guidelines were fully funded by the AGA Institute with no funding from any outside agency or industry.

Sultan is supported by the US Food and Drug Administration. Co-authors Shazia Mehmood Siddique, Dennis L. Shung, and Benjamin Lebwohl are supported by grants from the National Institute of Diabetes and Digestive and Kidney Diseases. Theodore R. Levin is supported by the Permanente Medical Group Delivery Science and Applied Research Program. Cesare Hassan is a consultant for Fujifilm and Olympus. Peter S. Liang reported doing research work for Freenome and advisory board work for Guardant Health and Natera.

Kim is the AGA president-elect. He disclosed no competing interests relevant to his comments.

A version of this article appeared on Medscape.com.

WASHINGTON, DC — Research on the gut microbiome — and clinical attention to it — has focused mainly on bacteria, but bacteriophages and fungi play critical roles as well, with significant influences on health and disease, experts said at the Gut Microbiota for Health (GMFH) World Summit 2025.

Fungi account for < 1% of the total genetic material in the microbiome but 1%-2% of its total biomass. “Despite their relative rarity, they have an important and outsized influence on gut health” — an impact that results from their unique interface with the immune system, said Kyla Ost, PhD, of the Anschutz Medical Campus, University of Colorado, in Denver, whose research focuses on this interface.

And bacteriophages — viruses that infect and kill bacteria — are highly abundant in the gut. “Bacteriophages begin to colonize our GI [gastrointestinal] tract at the same time we develop our own microbiome shortly after birth, and from that time on, they interact with the bacteria in our GI tract, shaping [and being shaped by] the bacterial species we carry with us,” said Robert (Chip) Schooley, MD, distinguished professor of medicine at the University of California San Diego School of Medicine.

“We’ve been talking about things that affect the gut microbiome — diet, genetics, immune response — but probably the biggest influence on what grows in the GI tract are bacteriophages,” said Schooley, co-director of the Center for Innovative Phage Applications and Therapeutics, in a session on the extra-bacterial gut ecosystem.

Among the current questions: How can phages be used to manipulate the gut microbiome and influence GI-related diseases? And how can the pathogenic potential of commensal fungi be limited?

 

‘New life’ for Phage Therapy

Bacteriophages represent a promising approach for the treatment of multidrug resistant bacterial pathogens in an era of increasing resistance and a dried-up antibiotic discovery pipeline, Schooley said. (In 2019, an estimated 4.95 million deaths around the world were associated with bacterial antimicrobial resistance, and by 2050, it has been forecast that this number will rise to an estimated 8.22 million deaths.)

But in addition to suppressing bacterial pathogens causing direct morbidity, phage therapy has the potential to suppress bacteria believed to contribute to chronic diseases, he said. “We have proof-of-concept studies about the ability of phage to modulate bacteria in the digestive tract,” and an increasing number of clinical trials of the use of phages in GI and other diseases are underway, he said.

Phages were discovered just over a century ago, but phage therapy was widely abandoned once antibiotics were developed, except for in Russia and the former Eastern Bloc countries, where phage therapy continued to be used.

Phage therapy “got new life” in the West, Schooley said, about 10-15 years ago with an increasing number of detailed and high-profile case reports, including one in which a UC San Diego colleague, Tom Patterson, PhD, contracted a deadly multidrug resistant bacterial infection in Egypt and was eventually saved with bacteriophage therapy. (The case was the subject of the book The Perfect Predator).

Since then, as described in case reports and studies in the literature, “hundreds of people have been treated with bacteriophages here and in Europe,” most commonly for pulmonary infections and infections in implanted vascular and orthopedic devices, said Schooley, who coauthored a review in Cell in 2023 that describes phage biology and advances and future directions in phage therapy.

The use of bacteriophages to prevent systemic infections during high-risk periods — such as during chemotherapeutic regimens for hematological regimens — is an area of interest, he said at the meeting.

In research that is making its way to a clinical trial of patients undergoing allogeneic hematopoietic stem cell transplant (HSCT), researchers screened a library of phages to identify those with broad coverage of Escherichia coli. Using tail fiber engineering and CRISPR technology, they then engineered a combination of the four most complementary bacteriophages to selectively kill E coli — including fluoroquinolone-resistant strains that, in patients whose GI tracts are colonized with these strains, can translocate from the gut into the bloodstream, causing sepsis, during chemotherapeutic regimens for HSCT.

In a mouse model, the CRISPR-enhanced four-phage cocktail (SNIPR001) led to a steady reduction in the E coli colony counts in stool, “showing you can modulate these bacteria in the gut by using bacteriophages to kill them,” Schooley said. Moreover, the CRISPR enhancement strengthened the phages’ ability to break up biofilms, he said, showing “that you can engineer bacteriophages to make them better killers.” A phase 1b/2a study is being planned.

 

Other Niches for Therapeutic Phages, Challenges

Bacteriophages also could be used to target a gut bacterium that has been shown to attenuate alcoholic liver disease. Patients with alcoholic hepatitis “have a gut microbiome that is different in distribution,” Schooley said, often with increased numbers of Enterococcus faecalis that produce cytolysin, an exotoxin that exacerbates liver injury and is associated with increased mortality.

In published research led by investigators at UC San Diego, stool from cytolysin-positive patients with alcoholic hepatitis was found to exacerbate ethanol-induced liver disease in gnotobiotic mice, and phage therapy against cytolytic E faecalis was found to abolish it, Schooley shared.

Research is also exploring the potential of phage therapy to selectively target adherent invasive E coli in Crohn’s disease, and Klebsiella pneumoniae in the gut microbiome as an exacerbator of inflammatory bowel disease (IBD), he said.

And investigators in Japan, he noted, have reported that bacteriophage therapy against K pneumoniae can ameliorate liver inflammation and disease severity in primary sclerosing cholangitis.

Challenges in the therapeutic use of phages include the narrow host range of phages and an uncertain predictive value of in vitro phage susceptibility testing. “We don’t know yet how to do resistance testing as well as we do with antibiotics,” he said.

In addition, most phages tend to be acid labile, requiring strategies to mitigate inactivation by gastric acid, and there are “major knowledge gaps” relating to phage pharmacology. “We also know that adaptive immune responses to phages can but often doesn’t impact therapy, and we want to understand that better in clinical trials,” Schooley said.

Phages that have a “lysogenic” lifestyle — as opposed to lytic phages which are used therapeutically — can contribute to antibiotic resistance by facilitating the interchange of bacterial resistance genes, he noted.

 

A Window Into the Mycobiome

The human gut mycobiome is primarily composed of fungi in the Saccharomyces, Candida, and Malassezia genera, with Candida species dominating. Fungal cells harbor distinct immune-stimulatory molecules and activate distinct immune pathways compared with bacteria and other members of the microbiome, said Ost, assistant professor in the immunology and microbiology department of CU Anschutz.

Some fungi, including those in the Candida genus, activate adaptive and innate immune responses that promote metabolic health and protect against infection. A recently published study in Science, for instance, demonstrated that colonization with C dubliniensis in very young mice who had been exposed to broad-spectrum antibiotics promoted “the expansion and development of beta cells in the pancreas” in a macrophage dependent manner, improving metabolic health and reducing diabetes incidence, she shared.

On the one hand, fungi can “exacerbate and perpetuate the pathogenic inflammation that’s found in a growing list of inflammatory diseases” such as IBD. And “in fact, a lot of the benefits and detriments are driven by the exact same species of fungi,” said Ost. “This is particularly true of Candida,” which is a “lifelong colonizer of intestinal microbiota that rarely causes disease but can be quite pathogenic when it does.”

A 2023 review in Nature Reviews Gastroenterology & Hepatology coauthored by Ost describes the role of commensal fungi in intestinal diseases, including IBD, colorectal cancer, and pancreatic cancer.

The pathogenic potential of commensal fungi is largely dependent on its strain, its morphology and its expression of virulence factors, researchers are learning. Ost has studied C albicans, which has been associated with intestinal inflammation and IBD. Like some other Candida species, C albicans are “fascinating shape shifters,” she said, transitioning between a less pathogenic “yeast” morphology and an elongated, adhesive “hyphae” shape that is more pathogenic.

It turns out, according to research by Ost and others, that the C albicans hyphal morphotype — and the adhesins (sticky proteins that facilitate adherence to epithelial cells) and a cytolytic toxin it produces — are preferentially targeted and suppressed by immunoglobulin A (IgA) in the gut.

“Our gut is protected by a large quantity of IgA antibodies…and these IgA interact with the microbiota and play a big role in what microbes are there and the biology of the microbes,” Ost said. Indeed, symptomatic IgA deficiency in humans has been shown to be associated with C albicans overgrowth.

Leveraging the hyphal-specific IgA response to protect against disease seems possible, she said, referring to an experimental anti-Candida fungal vaccine (NDV-3A) designed to induce an adhesin-specific immune response. In a mouse model of colitis, the vaccine protected against C albicans-associated damage. “We saw an immediate IgA response that targeted C albicans in the intestinal contents,” Ost said.

C glabrata, which has also been associated with intestinal inflammation and IBD, does not form hyphae but — depending on the strain — may also induce intestinal IgA responses, she said in describing her recent research.

Ost reported having no disclosures. Schooley disclosed being a consultant for SNIPR Biome, BiomX, Locus, MicrobiotiX, Amazon Data Monitoring Committee: Merck.

A version of this article appeared on Medscape.com.

WASHINGTON, DC — Research on the gut microbiome — and clinical attention to it — has focused mainly on bacteria, but bacteriophages and fungi play critical roles as well, with significant influences on health and disease, experts said at the Gut Microbiota for Health (GMFH) World Summit 2025.

Fungi account for < 1% of the total genetic material in the microbiome but 1%-2% of its total biomass. “Despite their relative rarity, they have an important and outsized influence on gut health” — an impact that results from their unique interface with the immune system, said Kyla Ost, PhD, of the Anschutz Medical Campus, University of Colorado, in Denver, whose research focuses on this interface.

And bacteriophages — viruses that infect and kill bacteria — are highly abundant in the gut. “Bacteriophages begin to colonize our GI [gastrointestinal] tract at the same time we develop our own microbiome shortly after birth, and from that time on, they interact with the bacteria in our GI tract, shaping [and being shaped by] the bacterial species we carry with us,” said Robert (Chip) Schooley, MD, distinguished professor of medicine at the University of California San Diego School of Medicine.

“We’ve been talking about things that affect the gut microbiome — diet, genetics, immune response — but probably the biggest influence on what grows in the GI tract are bacteriophages,” said Schooley, co-director of the Center for Innovative Phage Applications and Therapeutics, in a session on the extra-bacterial gut ecosystem.

Among the current questions: How can phages be used to manipulate the gut microbiome and influence GI-related diseases? And how can the pathogenic potential of commensal fungi be limited?

 

‘New life’ for Phage Therapy

Bacteriophages represent a promising approach for the treatment of multidrug resistant bacterial pathogens in an era of increasing resistance and a dried-up antibiotic discovery pipeline, Schooley said. (In 2019, an estimated 4.95 million deaths around the world were associated with bacterial antimicrobial resistance, and by 2050, it has been forecast that this number will rise to an estimated 8.22 million deaths.)

But in addition to suppressing bacterial pathogens causing direct morbidity, phage therapy has the potential to suppress bacteria believed to contribute to chronic diseases, he said. “We have proof-of-concept studies about the ability of phage to modulate bacteria in the digestive tract,” and an increasing number of clinical trials of the use of phages in GI and other diseases are underway, he said.

Phages were discovered just over a century ago, but phage therapy was widely abandoned once antibiotics were developed, except for in Russia and the former Eastern Bloc countries, where phage therapy continued to be used.

Phage therapy “got new life” in the West, Schooley said, about 10-15 years ago with an increasing number of detailed and high-profile case reports, including one in which a UC San Diego colleague, Tom Patterson, PhD, contracted a deadly multidrug resistant bacterial infection in Egypt and was eventually saved with bacteriophage therapy. (The case was the subject of the book The Perfect Predator).

Since then, as described in case reports and studies in the literature, “hundreds of people have been treated with bacteriophages here and in Europe,” most commonly for pulmonary infections and infections in implanted vascular and orthopedic devices, said Schooley, who coauthored a review in Cell in 2023 that describes phage biology and advances and future directions in phage therapy.

The use of bacteriophages to prevent systemic infections during high-risk periods — such as during chemotherapeutic regimens for hematological regimens — is an area of interest, he said at the meeting.

In research that is making its way to a clinical trial of patients undergoing allogeneic hematopoietic stem cell transplant (HSCT), researchers screened a library of phages to identify those with broad coverage of Escherichia coli. Using tail fiber engineering and CRISPR technology, they then engineered a combination of the four most complementary bacteriophages to selectively kill E coli — including fluoroquinolone-resistant strains that, in patients whose GI tracts are colonized with these strains, can translocate from the gut into the bloodstream, causing sepsis, during chemotherapeutic regimens for HSCT.

In a mouse model, the CRISPR-enhanced four-phage cocktail (SNIPR001) led to a steady reduction in the E coli colony counts in stool, “showing you can modulate these bacteria in the gut by using bacteriophages to kill them,” Schooley said. Moreover, the CRISPR enhancement strengthened the phages’ ability to break up biofilms, he said, showing “that you can engineer bacteriophages to make them better killers.” A phase 1b/2a study is being planned.

 

Other Niches for Therapeutic Phages, Challenges

Bacteriophages also could be used to target a gut bacterium that has been shown to attenuate alcoholic liver disease. Patients with alcoholic hepatitis “have a gut microbiome that is different in distribution,” Schooley said, often with increased numbers of Enterococcus faecalis that produce cytolysin, an exotoxin that exacerbates liver injury and is associated with increased mortality.

In published research led by investigators at UC San Diego, stool from cytolysin-positive patients with alcoholic hepatitis was found to exacerbate ethanol-induced liver disease in gnotobiotic mice, and phage therapy against cytolytic E faecalis was found to abolish it, Schooley shared.

Research is also exploring the potential of phage therapy to selectively target adherent invasive E coli in Crohn’s disease, and Klebsiella pneumoniae in the gut microbiome as an exacerbator of inflammatory bowel disease (IBD), he said.

And investigators in Japan, he noted, have reported that bacteriophage therapy against K pneumoniae can ameliorate liver inflammation and disease severity in primary sclerosing cholangitis.

Challenges in the therapeutic use of phages include the narrow host range of phages and an uncertain predictive value of in vitro phage susceptibility testing. “We don’t know yet how to do resistance testing as well as we do with antibiotics,” he said.

In addition, most phages tend to be acid labile, requiring strategies to mitigate inactivation by gastric acid, and there are “major knowledge gaps” relating to phage pharmacology. “We also know that adaptive immune responses to phages can but often doesn’t impact therapy, and we want to understand that better in clinical trials,” Schooley said.

Phages that have a “lysogenic” lifestyle — as opposed to lytic phages which are used therapeutically — can contribute to antibiotic resistance by facilitating the interchange of bacterial resistance genes, he noted.

 

A Window Into the Mycobiome

The human gut mycobiome is primarily composed of fungi in the Saccharomyces, Candida, and Malassezia genera, with Candida species dominating. Fungal cells harbor distinct immune-stimulatory molecules and activate distinct immune pathways compared with bacteria and other members of the microbiome, said Ost, assistant professor in the immunology and microbiology department of CU Anschutz.

Some fungi, including those in the Candida genus, activate adaptive and innate immune responses that promote metabolic health and protect against infection. A recently published study in Science, for instance, demonstrated that colonization with C dubliniensis in very young mice who had been exposed to broad-spectrum antibiotics promoted “the expansion and development of beta cells in the pancreas” in a macrophage dependent manner, improving metabolic health and reducing diabetes incidence, she shared.

On the one hand, fungi can “exacerbate and perpetuate the pathogenic inflammation that’s found in a growing list of inflammatory diseases” such as IBD. And “in fact, a lot of the benefits and detriments are driven by the exact same species of fungi,” said Ost. “This is particularly true of Candida,” which is a “lifelong colonizer of intestinal microbiota that rarely causes disease but can be quite pathogenic when it does.”

A 2023 review in Nature Reviews Gastroenterology & Hepatology coauthored by Ost describes the role of commensal fungi in intestinal diseases, including IBD, colorectal cancer, and pancreatic cancer.

The pathogenic potential of commensal fungi is largely dependent on its strain, its morphology and its expression of virulence factors, researchers are learning. Ost has studied C albicans, which has been associated with intestinal inflammation and IBD. Like some other Candida species, C albicans are “fascinating shape shifters,” she said, transitioning between a less pathogenic “yeast” morphology and an elongated, adhesive “hyphae” shape that is more pathogenic.

It turns out, according to research by Ost and others, that the C albicans hyphal morphotype — and the adhesins (sticky proteins that facilitate adherence to epithelial cells) and a cytolytic toxin it produces — are preferentially targeted and suppressed by immunoglobulin A (IgA) in the gut.

“Our gut is protected by a large quantity of IgA antibodies…and these IgA interact with the microbiota and play a big role in what microbes are there and the biology of the microbes,” Ost said. Indeed, symptomatic IgA deficiency in humans has been shown to be associated with C albicans overgrowth.

Leveraging the hyphal-specific IgA response to protect against disease seems possible, she said, referring to an experimental anti-Candida fungal vaccine (NDV-3A) designed to induce an adhesin-specific immune response. In a mouse model of colitis, the vaccine protected against C albicans-associated damage. “We saw an immediate IgA response that targeted C albicans in the intestinal contents,” Ost said.

C glabrata, which has also been associated with intestinal inflammation and IBD, does not form hyphae but — depending on the strain — may also induce intestinal IgA responses, she said in describing her recent research.

Ost reported having no disclosures. Schooley disclosed being a consultant for SNIPR Biome, BiomX, Locus, MicrobiotiX, Amazon Data Monitoring Committee: Merck.

A version of this article appeared on Medscape.com.

WASHINGTON, DC — Research on the gut microbiome — and clinical attention to it — has focused mainly on bacteria, but bacteriophages and fungi play critical roles as well, with significant influences on health and disease, experts said at the Gut Microbiota for Health (GMFH) World Summit 2025.

Fungi account for < 1% of the total genetic material in the microbiome but 1%-2% of its total biomass. “Despite their relative rarity, they have an important and outsized influence on gut health” — an impact that results from their unique interface with the immune system, said Kyla Ost, PhD, of the Anschutz Medical Campus, University of Colorado, in Denver, whose research focuses on this interface.

And bacteriophages — viruses that infect and kill bacteria — are highly abundant in the gut. “Bacteriophages begin to colonize our GI [gastrointestinal] tract at the same time we develop our own microbiome shortly after birth, and from that time on, they interact with the bacteria in our GI tract, shaping [and being shaped by] the bacterial species we carry with us,” said Robert (Chip) Schooley, MD, distinguished professor of medicine at the University of California San Diego School of Medicine.

“We’ve been talking about things that affect the gut microbiome — diet, genetics, immune response — but probably the biggest influence on what grows in the GI tract are bacteriophages,” said Schooley, co-director of the Center for Innovative Phage Applications and Therapeutics, in a session on the extra-bacterial gut ecosystem.

Among the current questions: How can phages be used to manipulate the gut microbiome and influence GI-related diseases? And how can the pathogenic potential of commensal fungi be limited?

 

‘New life’ for Phage Therapy

Bacteriophages represent a promising approach for the treatment of multidrug resistant bacterial pathogens in an era of increasing resistance and a dried-up antibiotic discovery pipeline, Schooley said. (In 2019, an estimated 4.95 million deaths around the world were associated with bacterial antimicrobial resistance, and by 2050, it has been forecast that this number will rise to an estimated 8.22 million deaths.)

But in addition to suppressing bacterial pathogens causing direct morbidity, phage therapy has the potential to suppress bacteria believed to contribute to chronic diseases, he said. “We have proof-of-concept studies about the ability of phage to modulate bacteria in the digestive tract,” and an increasing number of clinical trials of the use of phages in GI and other diseases are underway, he said.

Phages were discovered just over a century ago, but phage therapy was widely abandoned once antibiotics were developed, except for in Russia and the former Eastern Bloc countries, where phage therapy continued to be used.

Phage therapy “got new life” in the West, Schooley said, about 10-15 years ago with an increasing number of detailed and high-profile case reports, including one in which a UC San Diego colleague, Tom Patterson, PhD, contracted a deadly multidrug resistant bacterial infection in Egypt and was eventually saved with bacteriophage therapy. (The case was the subject of the book The Perfect Predator).

Since then, as described in case reports and studies in the literature, “hundreds of people have been treated with bacteriophages here and in Europe,” most commonly for pulmonary infections and infections in implanted vascular and orthopedic devices, said Schooley, who coauthored a review in Cell in 2023 that describes phage biology and advances and future directions in phage therapy.

The use of bacteriophages to prevent systemic infections during high-risk periods — such as during chemotherapeutic regimens for hematological regimens — is an area of interest, he said at the meeting.

In research that is making its way to a clinical trial of patients undergoing allogeneic hematopoietic stem cell transplant (HSCT), researchers screened a library of phages to identify those with broad coverage of Escherichia coli. Using tail fiber engineering and CRISPR technology, they then engineered a combination of the four most complementary bacteriophages to selectively kill E coli — including fluoroquinolone-resistant strains that, in patients whose GI tracts are colonized with these strains, can translocate from the gut into the bloodstream, causing sepsis, during chemotherapeutic regimens for HSCT.

In a mouse model, the CRISPR-enhanced four-phage cocktail (SNIPR001) led to a steady reduction in the E coli colony counts in stool, “showing you can modulate these bacteria in the gut by using bacteriophages to kill them,” Schooley said. Moreover, the CRISPR enhancement strengthened the phages’ ability to break up biofilms, he said, showing “that you can engineer bacteriophages to make them better killers.” A phase 1b/2a study is being planned.

 

Other Niches for Therapeutic Phages, Challenges

Bacteriophages also could be used to target a gut bacterium that has been shown to attenuate alcoholic liver disease. Patients with alcoholic hepatitis “have a gut microbiome that is different in distribution,” Schooley said, often with increased numbers of Enterococcus faecalis that produce cytolysin, an exotoxin that exacerbates liver injury and is associated with increased mortality.

In published research led by investigators at UC San Diego, stool from cytolysin-positive patients with alcoholic hepatitis was found to exacerbate ethanol-induced liver disease in gnotobiotic mice, and phage therapy against cytolytic E faecalis was found to abolish it, Schooley shared.

Research is also exploring the potential of phage therapy to selectively target adherent invasive E coli in Crohn’s disease, and Klebsiella pneumoniae in the gut microbiome as an exacerbator of inflammatory bowel disease (IBD), he said.

And investigators in Japan, he noted, have reported that bacteriophage therapy against K pneumoniae can ameliorate liver inflammation and disease severity in primary sclerosing cholangitis.

Challenges in the therapeutic use of phages include the narrow host range of phages and an uncertain predictive value of in vitro phage susceptibility testing. “We don’t know yet how to do resistance testing as well as we do with antibiotics,” he said.

In addition, most phages tend to be acid labile, requiring strategies to mitigate inactivation by gastric acid, and there are “major knowledge gaps” relating to phage pharmacology. “We also know that adaptive immune responses to phages can but often doesn’t impact therapy, and we want to understand that better in clinical trials,” Schooley said.

Phages that have a “lysogenic” lifestyle — as opposed to lytic phages which are used therapeutically — can contribute to antibiotic resistance by facilitating the interchange of bacterial resistance genes, he noted.

 

A Window Into the Mycobiome

The human gut mycobiome is primarily composed of fungi in the Saccharomyces, Candida, and Malassezia genera, with Candida species dominating. Fungal cells harbor distinct immune-stimulatory molecules and activate distinct immune pathways compared with bacteria and other members of the microbiome, said Ost, assistant professor in the immunology and microbiology department of CU Anschutz.

Some fungi, including those in the Candida genus, activate adaptive and innate immune responses that promote metabolic health and protect against infection. A recently published study in Science, for instance, demonstrated that colonization with C dubliniensis in very young mice who had been exposed to broad-spectrum antibiotics promoted “the expansion and development of beta cells in the pancreas” in a macrophage dependent manner, improving metabolic health and reducing diabetes incidence, she shared.

On the one hand, fungi can “exacerbate and perpetuate the pathogenic inflammation that’s found in a growing list of inflammatory diseases” such as IBD. And “in fact, a lot of the benefits and detriments are driven by the exact same species of fungi,” said Ost. “This is particularly true of Candida,” which is a “lifelong colonizer of intestinal microbiota that rarely causes disease but can be quite pathogenic when it does.”

A 2023 review in Nature Reviews Gastroenterology & Hepatology coauthored by Ost describes the role of commensal fungi in intestinal diseases, including IBD, colorectal cancer, and pancreatic cancer.

The pathogenic potential of commensal fungi is largely dependent on its strain, its morphology and its expression of virulence factors, researchers are learning. Ost has studied C albicans, which has been associated with intestinal inflammation and IBD. Like some other Candida species, C albicans are “fascinating shape shifters,” she said, transitioning between a less pathogenic “yeast” morphology and an elongated, adhesive “hyphae” shape that is more pathogenic.

It turns out, according to research by Ost and others, that the C albicans hyphal morphotype — and the adhesins (sticky proteins that facilitate adherence to epithelial cells) and a cytolytic toxin it produces — are preferentially targeted and suppressed by immunoglobulin A (IgA) in the gut.

“Our gut is protected by a large quantity of IgA antibodies…and these IgA interact with the microbiota and play a big role in what microbes are there and the biology of the microbes,” Ost said. Indeed, symptomatic IgA deficiency in humans has been shown to be associated with C albicans overgrowth.

Leveraging the hyphal-specific IgA response to protect against disease seems possible, she said, referring to an experimental anti-Candida fungal vaccine (NDV-3A) designed to induce an adhesin-specific immune response. In a mouse model of colitis, the vaccine protected against C albicans-associated damage. “We saw an immediate IgA response that targeted C albicans in the intestinal contents,” Ost said.

C glabrata, which has also been associated with intestinal inflammation and IBD, does not form hyphae but — depending on the strain — may also induce intestinal IgA responses, she said in describing her recent research.

Ost reported having no disclosures. Schooley disclosed being a consultant for SNIPR Biome, BiomX, Locus, MicrobiotiX, Amazon Data Monitoring Committee: Merck.

A version of this article appeared on Medscape.com.

Patient navigation was more effective than usual care in increasing follow-up colonoscopy rates after an abnormal stool test result, a new randomized controlled trial revealed.

The intervention led to a significant 13-point increase in follow-up colonoscopy completion at 1 year, compared with usual care (55.1% vs 42.1%), according the study, which was published online in Annals of Internal Medicine.

 

“Patients with an abnormal fecal test results have about a 1 in 20 chance of having colorectal cancer found, and many more will be found to have advanced adenomas that can be removed to prevent cancer,” Gloria Coronado, PhD, of Kaiser Permanente Center for Health Research, Portland, Oregon, and University of Arizona Cancer Center, Tucson, said in an interview.

“It is critical that these patients get a follow-up colonoscopy,” she said. “Patient navigation can accomplish this goal.”

 

‘Highly Effective’ Intervention

Researchers compared the effectiveness of a patient navigation program with that of usual care outreach in increasing follow-up colonoscopy completion after an abnormal stool test. They also developed a risk-prediction model that calculated a patient’s probability of obtaining a follow-up colonoscopy without navigation to determine if the addition of this intervention had a greater impact on those determined to be less likely to follow through.

The study included 967 patients from a community health center in Washington State who received an abnormal fecal test result within the prior month. The mean age of participants was 61 years, approximately 45% were women and 77% were White, and 18% preferred a Spanish-language intervention. In total, 479 patients received the intervention and 488 received usual care.

The intervention was delivered by a patient navigator who mailed introductory letters, sent text messages, and made live phone calls. In the calls, the navigators addressed the topics of barrier assessment and resolution, bowel preparation instruction and reminders, colonoscopy check-in, and understanding colonoscopy results and retesting intervals.

Patients in the usual-care group were contacted by a referral coordinator to schedule a follow-up colonoscopy appointment. If they couldn’t be reached initially, up to two follow-up attempts were made at 30 and 45 days after the referral date.

Patient navigation resulted in a significant 13% increase in follow-up, and those in this group completed a colonoscopy 27 days sooner than those in the usual care group (mean, 229 days vs 256 days).

Contrary to the authors’ expectation, the effectiveness of the intervention did not vary by patients’ predicted likelihood of obtaining a colonoscopy without navigation.

Notably, 20.3% of patients were unreachable or lost to follow-up, and 29.7% did not receive navigation. Among the 479 patients assigned to navigation, 79 (16.5%) declined participation and 56 (11.7%) were never reached.

The study was primarily conducted during the height of the COVID-19 pandemic, which created additional systemic and individual barriers to completing colonoscopies.

Nevertheless, the authors wrote, “our findings suggest that patient navigation is highly effective for patients eligible for colonoscopy.”

“Most patients who were reached were contacted with six or fewer phone attempts,” Coronado noted. “Further efforts are needed to determine how to reach and motivate patients [who did not participate] to get a follow-up colonoscopy.”

Coronado and colleagues are exploring ways to leverage artificial intelligence and virtual approaches to augment patient navigation programs — for example, by using a virtual navigator or low-cost automated tools to provide education to build patient confidence in getting a colonoscopy.

 

‘A Promising Tool’

“Colonoscopy completion after positive stool-based testing is critical to mitigating the impact of colon cancer,” commented Rajiv Bhuta, MD, assistant professor of clinical gastroenterology & hepatology, Lewis Katz School of Medicine, Temple University, Philadelphia, who was not involved in the study. “While prior studies assessing navigation have demonstrated improvements, none were as large enrollment-wise or as generalizable as the current study.”

That said, Bhuta said in an interview that the study could have provided more detail about coordination and communication with local gastrointestinal practices.

“Local ordering and prescribing practices vary and can significantly impact compliance rates. Were colonoscopies completed via an open access pathway or were the patients required to see a gastroenterologist first? How long was the average wait time for colonoscopy once scheduled? What were the local policies on requiring an escort after the procedure?”

He also noted that some aspects of the study — such as access to reduced-cost specialty care and free ride-share services — may limit generalizable to settings without such resources.

He added: “Although patient navigators for cancer treatment have mandated reimbursement, there is no current reimbursement for navigators for abnormal screening tests, another barrier to wide-spread implementation.”

Bhuta said that the dropout rate in the study mirrors that of his own real-world practice, which serves a high-risk, low-resource community. “I would specifically like to see research that provides behavioral insights on why patients respond positively to navigation — whether it is due to reminders, emotional support, or logistical assistance. Is it systemic barriers or patient disinterest or both that drives noncompliance?”

Despite these uncertainties and the need to refine implementation logistics, Bhuta concluded, “this strategy is a promising tool to reduce disparities and improve colorectal cancer outcomes. Clinicians should advocate for or implement structured follow-up systems, particularly in high-risk populations.”

The study was funded by the US National Cancer Institute. Coronado received a grant/contract from Guardant Health. Bhuta declared no relevant conflicts of interest.

A version of this article appeared on Medscape.com.

Patient navigation was more effective than usual care in increasing follow-up colonoscopy rates after an abnormal stool test result, a new randomized controlled trial revealed.

The intervention led to a significant 13-point increase in follow-up colonoscopy completion at 1 year, compared with usual care (55.1% vs 42.1%), according the study, which was published online in Annals of Internal Medicine.

 

“Patients with an abnormal fecal test results have about a 1 in 20 chance of having colorectal cancer found, and many more will be found to have advanced adenomas that can be removed to prevent cancer,” Gloria Coronado, PhD, of Kaiser Permanente Center for Health Research, Portland, Oregon, and University of Arizona Cancer Center, Tucson, said in an interview.

“It is critical that these patients get a follow-up colonoscopy,” she said. “Patient navigation can accomplish this goal.”

 

‘Highly Effective’ Intervention

Researchers compared the effectiveness of a patient navigation program with that of usual care outreach in increasing follow-up colonoscopy completion after an abnormal stool test. They also developed a risk-prediction model that calculated a patient’s probability of obtaining a follow-up colonoscopy without navigation to determine if the addition of this intervention had a greater impact on those determined to be less likely to follow through.

The study included 967 patients from a community health center in Washington State who received an abnormal fecal test result within the prior month. The mean age of participants was 61 years, approximately 45% were women and 77% were White, and 18% preferred a Spanish-language intervention. In total, 479 patients received the intervention and 488 received usual care.

The intervention was delivered by a patient navigator who mailed introductory letters, sent text messages, and made live phone calls. In the calls, the navigators addressed the topics of barrier assessment and resolution, bowel preparation instruction and reminders, colonoscopy check-in, and understanding colonoscopy results and retesting intervals.

Patients in the usual-care group were contacted by a referral coordinator to schedule a follow-up colonoscopy appointment. If they couldn’t be reached initially, up to two follow-up attempts were made at 30 and 45 days after the referral date.

Patient navigation resulted in a significant 13% increase in follow-up, and those in this group completed a colonoscopy 27 days sooner than those in the usual care group (mean, 229 days vs 256 days).

Contrary to the authors’ expectation, the effectiveness of the intervention did not vary by patients’ predicted likelihood of obtaining a colonoscopy without navigation.

Notably, 20.3% of patients were unreachable or lost to follow-up, and 29.7% did not receive navigation. Among the 479 patients assigned to navigation, 79 (16.5%) declined participation and 56 (11.7%) were never reached.

The study was primarily conducted during the height of the COVID-19 pandemic, which created additional systemic and individual barriers to completing colonoscopies.

Nevertheless, the authors wrote, “our findings suggest that patient navigation is highly effective for patients eligible for colonoscopy.”

“Most patients who were reached were contacted with six or fewer phone attempts,” Coronado noted. “Further efforts are needed to determine how to reach and motivate patients [who did not participate] to get a follow-up colonoscopy.”

Coronado and colleagues are exploring ways to leverage artificial intelligence and virtual approaches to augment patient navigation programs — for example, by using a virtual navigator or low-cost automated tools to provide education to build patient confidence in getting a colonoscopy.

 

‘A Promising Tool’

“Colonoscopy completion after positive stool-based testing is critical to mitigating the impact of colon cancer,” commented Rajiv Bhuta, MD, assistant professor of clinical gastroenterology & hepatology, Lewis Katz School of Medicine, Temple University, Philadelphia, who was not involved in the study. “While prior studies assessing navigation have demonstrated improvements, none were as large enrollment-wise or as generalizable as the current study.”

That said, Bhuta said in an interview that the study could have provided more detail about coordination and communication with local gastrointestinal practices.

“Local ordering and prescribing practices vary and can significantly impact compliance rates. Were colonoscopies completed via an open access pathway or were the patients required to see a gastroenterologist first? How long was the average wait time for colonoscopy once scheduled? What were the local policies on requiring an escort after the procedure?”

He also noted that some aspects of the study — such as access to reduced-cost specialty care and free ride-share services — may limit generalizable to settings without such resources.

He added: “Although patient navigators for cancer treatment have mandated reimbursement, there is no current reimbursement for navigators for abnormal screening tests, another barrier to wide-spread implementation.”

Bhuta said that the dropout rate in the study mirrors that of his own real-world practice, which serves a high-risk, low-resource community. “I would specifically like to see research that provides behavioral insights on why patients respond positively to navigation — whether it is due to reminders, emotional support, or logistical assistance. Is it systemic barriers or patient disinterest or both that drives noncompliance?”

Despite these uncertainties and the need to refine implementation logistics, Bhuta concluded, “this strategy is a promising tool to reduce disparities and improve colorectal cancer outcomes. Clinicians should advocate for or implement structured follow-up systems, particularly in high-risk populations.”

The study was funded by the US National Cancer Institute. Coronado received a grant/contract from Guardant Health. Bhuta declared no relevant conflicts of interest.

A version of this article appeared on Medscape.com.

Patient navigation was more effective than usual care in increasing follow-up colonoscopy rates after an abnormal stool test result, a new randomized controlled trial revealed.

The intervention led to a significant 13-point increase in follow-up colonoscopy completion at 1 year, compared with usual care (55.1% vs 42.1%), according the study, which was published online in Annals of Internal Medicine.

 

“Patients with an abnormal fecal test results have about a 1 in 20 chance of having colorectal cancer found, and many more will be found to have advanced adenomas that can be removed to prevent cancer,” Gloria Coronado, PhD, of Kaiser Permanente Center for Health Research, Portland, Oregon, and University of Arizona Cancer Center, Tucson, said in an interview.

“It is critical that these patients get a follow-up colonoscopy,” she said. “Patient navigation can accomplish this goal.”

 

‘Highly Effective’ Intervention

Researchers compared the effectiveness of a patient navigation program with that of usual care outreach in increasing follow-up colonoscopy completion after an abnormal stool test. They also developed a risk-prediction model that calculated a patient’s probability of obtaining a follow-up colonoscopy without navigation to determine if the addition of this intervention had a greater impact on those determined to be less likely to follow through.

The study included 967 patients from a community health center in Washington State who received an abnormal fecal test result within the prior month. The mean age of participants was 61 years, approximately 45% were women and 77% were White, and 18% preferred a Spanish-language intervention. In total, 479 patients received the intervention and 488 received usual care.

The intervention was delivered by a patient navigator who mailed introductory letters, sent text messages, and made live phone calls. In the calls, the navigators addressed the topics of barrier assessment and resolution, bowel preparation instruction and reminders, colonoscopy check-in, and understanding colonoscopy results and retesting intervals.

Patients in the usual-care group were contacted by a referral coordinator to schedule a follow-up colonoscopy appointment. If they couldn’t be reached initially, up to two follow-up attempts were made at 30 and 45 days after the referral date.

Patient navigation resulted in a significant 13% increase in follow-up, and those in this group completed a colonoscopy 27 days sooner than those in the usual care group (mean, 229 days vs 256 days).

Contrary to the authors’ expectation, the effectiveness of the intervention did not vary by patients’ predicted likelihood of obtaining a colonoscopy without navigation.

Notably, 20.3% of patients were unreachable or lost to follow-up, and 29.7% did not receive navigation. Among the 479 patients assigned to navigation, 79 (16.5%) declined participation and 56 (11.7%) were never reached.

The study was primarily conducted during the height of the COVID-19 pandemic, which created additional systemic and individual barriers to completing colonoscopies.

Nevertheless, the authors wrote, “our findings suggest that patient navigation is highly effective for patients eligible for colonoscopy.”

“Most patients who were reached were contacted with six or fewer phone attempts,” Coronado noted. “Further efforts are needed to determine how to reach and motivate patients [who did not participate] to get a follow-up colonoscopy.”

Coronado and colleagues are exploring ways to leverage artificial intelligence and virtual approaches to augment patient navigation programs — for example, by using a virtual navigator or low-cost automated tools to provide education to build patient confidence in getting a colonoscopy.

 

‘A Promising Tool’

“Colonoscopy completion after positive stool-based testing is critical to mitigating the impact of colon cancer,” commented Rajiv Bhuta, MD, assistant professor of clinical gastroenterology & hepatology, Lewis Katz School of Medicine, Temple University, Philadelphia, who was not involved in the study. “While prior studies assessing navigation have demonstrated improvements, none were as large enrollment-wise or as generalizable as the current study.”

That said, Bhuta said in an interview that the study could have provided more detail about coordination and communication with local gastrointestinal practices.

“Local ordering and prescribing practices vary and can significantly impact compliance rates. Were colonoscopies completed via an open access pathway or were the patients required to see a gastroenterologist first? How long was the average wait time for colonoscopy once scheduled? What were the local policies on requiring an escort after the procedure?”

He also noted that some aspects of the study — such as access to reduced-cost specialty care and free ride-share services — may limit generalizable to settings without such resources.

He added: “Although patient navigators for cancer treatment have mandated reimbursement, there is no current reimbursement for navigators for abnormal screening tests, another barrier to wide-spread implementation.”

Bhuta said that the dropout rate in the study mirrors that of his own real-world practice, which serves a high-risk, low-resource community. “I would specifically like to see research that provides behavioral insights on why patients respond positively to navigation — whether it is due to reminders, emotional support, or logistical assistance. Is it systemic barriers or patient disinterest or both that drives noncompliance?”

Despite these uncertainties and the need to refine implementation logistics, Bhuta concluded, “this strategy is a promising tool to reduce disparities and improve colorectal cancer outcomes. Clinicians should advocate for or implement structured follow-up systems, particularly in high-risk populations.”

The study was funded by the US National Cancer Institute. Coronado received a grant/contract from Guardant Health. Bhuta declared no relevant conflicts of interest.

A version of this article appeared on Medscape.com.