Alternatives to Traditional Colonoscopy Sought

LAS VEGAS — Capsule colonoscopy achieved a higher sensitivity for detecting polyps than did virtual colonoscopy in a comparative study presented at the annual meeting of the American College of Gastroenterology.

Two studies presented at the meeting focused on early clinical trials using the PillCam, a 31-mm capsule fitted with two video cameras, each capable of taking two frames per second during a journey of about 10 hours through the gastrointestinal tract. The investigational device, manufactured by Given Imaging Ltd., of Yoqneam, Israel, has not yet received Food and Drug Administration approval for colonoscopy. The company sponsored both studies.

Capsule colonoscopy requires bowel cleansing, as does traditional colonoscopy, but permits “direct visualization of the colon mucosa with no sedation, no insufflation, and no radiation,” said Dr. Rami Eliakim of Rambam Medical Center in Haifa, Israel, director of a three-center, prospective feasibility trial of capsule colonoscopy. Among 84 Israeli patients who underwent both tests for colorectal cancer screening or symptoms, polyps were detected in 34 by capsule colonoscopy and in 36 by traditional colonoscopy. Polyps considered “significant” were detected in 14 patients by capsule colonoscopy and in 16 by traditional colonoscopy.

Each test detected some polyps that the other test missed. Repeated traditional colonoscopies in four patients confirmed the presence of polyps seen only by capsule colonoscopy the first time around.

Dr. Blair Lewis, a gastroenterologist at Mount Sinai School of Medicine in New York, reported on a three-way, blinded, multicenter study comparing capsule colonoscopy, virtual colonoscopy, and traditional colonoscopy in 51 patients at average or high risk for colorectal cancer.

Seventeen precancerous polyps were found in 15 patients: 12 detected by capsule colonoscopy, 5 by virtual colonoscopy, and 16 by traditional colonoscopy. Results suggest capsule colonoscopy was “more sensitive than was virtual colonoscopy and almost [as] sensitive as standard colonos-copy,” Dr. Lewis said during a press briefing. Although capsule colonoscopy is still investigational, Dr. Lewis said he could envision its eventual usefulness in examining the right colon in patients with a prior incomplete colonoscopy, and patients who cannot undergo traditional colonoscopy.

Dr. Steven H. Itzkowitz announced during the meeting that a refined version of a stool-derived DNA test achieved a sensitivity for detecting colon cancer of 88%, a considerable improvement over the commercially available DNA test, which has a sensitivity of about 52%–53%.

The specificity for the new test is just 82%, potentially explained by the fact that one of the two markers targeted by the test is a methylated gene. Presumed “false positives” may be an age-related phenomenon, or the test may be picking up the earliest sign of transformation of a gene in a person destined to get colorectal cancer.

“We don't know how [these new technologies] interdigitate with colonoscopy,” said Dr. Itzkowitz, professor of medicine at Mount Sinai School of Medicine. “If there is a miss rate for colonoscopies, what do we do between colonoscopies? Maybe one of the roles for these noninvasive technologies is to use them 1 year later.”

LAS VEGAS — Capsule colonoscopy achieved a higher sensitivity for detecting polyps than did virtual colonoscopy in a comparative study presented at the annual meeting of the American College of Gastroenterology.

Two studies presented at the meeting focused on early clinical trials using the PillCam, a 31-mm capsule fitted with two video cameras, each capable of taking two frames per second during a journey of about 10 hours through the gastrointestinal tract. The investigational device, manufactured by Given Imaging Ltd., of Yoqneam, Israel, has not yet received Food and Drug Administration approval for colonoscopy. The company sponsored both studies.

Capsule colonoscopy requires bowel cleansing, as does traditional colonoscopy, but permits “direct visualization of the colon mucosa with no sedation, no insufflation, and no radiation,” said Dr. Rami Eliakim of Rambam Medical Center in Haifa, Israel, director of a three-center, prospective feasibility trial of capsule colonoscopy. Among 84 Israeli patients who underwent both tests for colorectal cancer screening or symptoms, polyps were detected in 34 by capsule colonoscopy and in 36 by traditional colonoscopy. Polyps considered “significant” were detected in 14 patients by capsule colonoscopy and in 16 by traditional colonoscopy.

Each test detected some polyps that the other test missed. Repeated traditional colonoscopies in four patients confirmed the presence of polyps seen only by capsule colonoscopy the first time around.

Dr. Blair Lewis, a gastroenterologist at Mount Sinai School of Medicine in New York, reported on a three-way, blinded, multicenter study comparing capsule colonoscopy, virtual colonoscopy, and traditional colonoscopy in 51 patients at average or high risk for colorectal cancer.

Seventeen precancerous polyps were found in 15 patients: 12 detected by capsule colonoscopy, 5 by virtual colonoscopy, and 16 by traditional colonoscopy. Results suggest capsule colonoscopy was “more sensitive than was virtual colonoscopy and almost [as] sensitive as standard colonos-copy,” Dr. Lewis said during a press briefing. Although capsule colonoscopy is still investigational, Dr. Lewis said he could envision its eventual usefulness in examining the right colon in patients with a prior incomplete colonoscopy, and patients who cannot undergo traditional colonoscopy.

Dr. Steven H. Itzkowitz announced during the meeting that a refined version of a stool-derived DNA test achieved a sensitivity for detecting colon cancer of 88%, a considerable improvement over the commercially available DNA test, which has a sensitivity of about 52%–53%.

The specificity for the new test is just 82%, potentially explained by the fact that one of the two markers targeted by the test is a methylated gene. Presumed “false positives” may be an age-related phenomenon, or the test may be picking up the earliest sign of transformation of a gene in a person destined to get colorectal cancer.

“We don't know how [these new technologies] interdigitate with colonoscopy,” said Dr. Itzkowitz, professor of medicine at Mount Sinai School of Medicine. “If there is a miss rate for colonoscopies, what do we do between colonoscopies? Maybe one of the roles for these noninvasive technologies is to use them 1 year later.”

LAS VEGAS — Capsule colonoscopy achieved a higher sensitivity for detecting polyps than did virtual colonoscopy in a comparative study presented at the annual meeting of the American College of Gastroenterology.

Two studies presented at the meeting focused on early clinical trials using the PillCam, a 31-mm capsule fitted with two video cameras, each capable of taking two frames per second during a journey of about 10 hours through the gastrointestinal tract. The investigational device, manufactured by Given Imaging Ltd., of Yoqneam, Israel, has not yet received Food and Drug Administration approval for colonoscopy. The company sponsored both studies.

Capsule colonoscopy requires bowel cleansing, as does traditional colonoscopy, but permits “direct visualization of the colon mucosa with no sedation, no insufflation, and no radiation,” said Dr. Rami Eliakim of Rambam Medical Center in Haifa, Israel, director of a three-center, prospective feasibility trial of capsule colonoscopy. Among 84 Israeli patients who underwent both tests for colorectal cancer screening or symptoms, polyps were detected in 34 by capsule colonoscopy and in 36 by traditional colonoscopy. Polyps considered “significant” were detected in 14 patients by capsule colonoscopy and in 16 by traditional colonoscopy.

Each test detected some polyps that the other test missed. Repeated traditional colonoscopies in four patients confirmed the presence of polyps seen only by capsule colonoscopy the first time around.

Dr. Blair Lewis, a gastroenterologist at Mount Sinai School of Medicine in New York, reported on a three-way, blinded, multicenter study comparing capsule colonoscopy, virtual colonoscopy, and traditional colonoscopy in 51 patients at average or high risk for colorectal cancer.

Seventeen precancerous polyps were found in 15 patients: 12 detected by capsule colonoscopy, 5 by virtual colonoscopy, and 16 by traditional colonoscopy. Results suggest capsule colonoscopy was “more sensitive than was virtual colonoscopy and almost [as] sensitive as standard colonos-copy,” Dr. Lewis said during a press briefing. Although capsule colonoscopy is still investigational, Dr. Lewis said he could envision its eventual usefulness in examining the right colon in patients with a prior incomplete colonoscopy, and patients who cannot undergo traditional colonoscopy.

Dr. Steven H. Itzkowitz announced during the meeting that a refined version of a stool-derived DNA test achieved a sensitivity for detecting colon cancer of 88%, a considerable improvement over the commercially available DNA test, which has a sensitivity of about 52%–53%.

The specificity for the new test is just 82%, potentially explained by the fact that one of the two markers targeted by the test is a methylated gene. Presumed “false positives” may be an age-related phenomenon, or the test may be picking up the earliest sign of transformation of a gene in a person destined to get colorectal cancer.

“We don't know how [these new technologies] interdigitate with colonoscopy,” said Dr. Itzkowitz, professor of medicine at Mount Sinai School of Medicine. “If there is a miss rate for colonoscopies, what do we do between colonoscopies? Maybe one of the roles for these noninvasive technologies is to use them 1 year later.”