Nonmelanoma Skin Cancer

LAS VEGAS – Merkel cell carcinoma, an extremely rare form of skin cancer, is often caused by a subclinical virus that routinely inhabits the skin. Now, a serum test of virus antibody levels is offering insight into the state of the disease, according to one dermatologist.

“If you have these antibodies, you have a better prognosis. You can follow those antibodies to test for recurrence or progression,” Isaac Brownell, MD, PhD, of the Dermatology Branch of the National Institutes of Health said at Skin Disease Education Foundation’s annual Las Vegas Dermatology Seminar.

The cancer appears in the skin’s Merkel cells, which contribute to our sense of touch by helping us to discriminate textures. “When you put your hand in your pocket, and you can tell the difference between the front and back of a quarter,” he said, “you’re using the Merkel cells in your fingertips.”

Only about 2,500 cases of Merkel cell carcinoma appear in the United States each year, Dr. Brownell said. It appears more often in elderly white patients, is more common in men than women, and is more likely among immunosuppressed patients, whose risk is increased 15- to 20-fold. Cases are more common in sunnier regions – at least in men – and lesions frequently appear on the head, face, and neck.

Five-year survival is estimated at 51% if the cancer is localized, according to a 2016 study of 9,387 cases that Dr. Brownell highlighted. But survival declines dramatically if it has spread to lymph nodes or distant sites (Ann Surg Oncol. 2016 Oct;23[11]:3564-71).

In recent years, researchers have linked 80% of Merkel cell carcinoma cases to the Merkel cell polyomavirus, he said. The virus normally inhabits our skin with no ill effects, he said. “We all have this virus on our skin. It’s everywhere, and even children have antibodies,” he said. But mutations can lead to Merkel cell carcinoma.

Does it matter if cases are polyomavirus positive or polyomavirus negative? Not really, Dr. Brownell said, since the presence of the virus doesn’t appear to affect overall prognosis. However, he said, serum antibody testing can be helpful in polyomavirus-positive patients because it offers insight into prognosis and tumor burden. For example, “if the baseline titer falls and then starts to go up, they’re likely to have a recurrence, and you’ll want to look out for that,” he said.

Dr. Brownell offered another bit of advice: Be prepared to respond to patients who worry that they have a contagious virus and could be a danger to others. The proper answer, he said, is this: “You don’t have to worry about infecting people. Your tumor is not making the virus, you’re not infectious, and we have the virus on us already.”

For more information about the antibody test, visit merkelcell.org/sero.

Dr. Brownell reported having no relevant disclosures. SDEF and this news organization are owned by the same parent company.

LAS VEGAS – Merkel cell carcinoma, an extremely rare form of skin cancer, is often caused by a subclinical virus that routinely inhabits the skin. Now, a serum test of virus antibody levels is offering insight into the state of the disease, according to one dermatologist.

“If you have these antibodies, you have a better prognosis. You can follow those antibodies to test for recurrence or progression,” Isaac Brownell, MD, PhD, of the Dermatology Branch of the National Institutes of Health said at Skin Disease Education Foundation’s annual Las Vegas Dermatology Seminar.

The cancer appears in the skin’s Merkel cells, which contribute to our sense of touch by helping us to discriminate textures. “When you put your hand in your pocket, and you can tell the difference between the front and back of a quarter,” he said, “you’re using the Merkel cells in your fingertips.”

Only about 2,500 cases of Merkel cell carcinoma appear in the United States each year, Dr. Brownell said. It appears more often in elderly white patients, is more common in men than women, and is more likely among immunosuppressed patients, whose risk is increased 15- to 20-fold. Cases are more common in sunnier regions – at least in men – and lesions frequently appear on the head, face, and neck.

Five-year survival is estimated at 51% if the cancer is localized, according to a 2016 study of 9,387 cases that Dr. Brownell highlighted. But survival declines dramatically if it has spread to lymph nodes or distant sites (Ann Surg Oncol. 2016 Oct;23[11]:3564-71).

In recent years, researchers have linked 80% of Merkel cell carcinoma cases to the Merkel cell polyomavirus, he said. The virus normally inhabits our skin with no ill effects, he said. “We all have this virus on our skin. It’s everywhere, and even children have antibodies,” he said. But mutations can lead to Merkel cell carcinoma.

Does it matter if cases are polyomavirus positive or polyomavirus negative? Not really, Dr. Brownell said, since the presence of the virus doesn’t appear to affect overall prognosis. However, he said, serum antibody testing can be helpful in polyomavirus-positive patients because it offers insight into prognosis and tumor burden. For example, “if the baseline titer falls and then starts to go up, they’re likely to have a recurrence, and you’ll want to look out for that,” he said.

Dr. Brownell offered another bit of advice: Be prepared to respond to patients who worry that they have a contagious virus and could be a danger to others. The proper answer, he said, is this: “You don’t have to worry about infecting people. Your tumor is not making the virus, you’re not infectious, and we have the virus on us already.”

For more information about the antibody test, visit merkelcell.org/sero.

Dr. Brownell reported having no relevant disclosures. SDEF and this news organization are owned by the same parent company.

LAS VEGAS – Merkel cell carcinoma, an extremely rare form of skin cancer, is often caused by a subclinical virus that routinely inhabits the skin. Now, a serum test of virus antibody levels is offering insight into the state of the disease, according to one dermatologist.

“If you have these antibodies, you have a better prognosis. You can follow those antibodies to test for recurrence or progression,” Isaac Brownell, MD, PhD, of the Dermatology Branch of the National Institutes of Health said at Skin Disease Education Foundation’s annual Las Vegas Dermatology Seminar.

The cancer appears in the skin’s Merkel cells, which contribute to our sense of touch by helping us to discriminate textures. “When you put your hand in your pocket, and you can tell the difference between the front and back of a quarter,” he said, “you’re using the Merkel cells in your fingertips.”

Only about 2,500 cases of Merkel cell carcinoma appear in the United States each year, Dr. Brownell said. It appears more often in elderly white patients, is more common in men than women, and is more likely among immunosuppressed patients, whose risk is increased 15- to 20-fold. Cases are more common in sunnier regions – at least in men – and lesions frequently appear on the head, face, and neck.

Five-year survival is estimated at 51% if the cancer is localized, according to a 2016 study of 9,387 cases that Dr. Brownell highlighted. But survival declines dramatically if it has spread to lymph nodes or distant sites (Ann Surg Oncol. 2016 Oct;23[11]:3564-71).

In recent years, researchers have linked 80% of Merkel cell carcinoma cases to the Merkel cell polyomavirus, he said. The virus normally inhabits our skin with no ill effects, he said. “We all have this virus on our skin. It’s everywhere, and even children have antibodies,” he said. But mutations can lead to Merkel cell carcinoma.

Does it matter if cases are polyomavirus positive or polyomavirus negative? Not really, Dr. Brownell said, since the presence of the virus doesn’t appear to affect overall prognosis. However, he said, serum antibody testing can be helpful in polyomavirus-positive patients because it offers insight into prognosis and tumor burden. For example, “if the baseline titer falls and then starts to go up, they’re likely to have a recurrence, and you’ll want to look out for that,” he said.

Dr. Brownell offered another bit of advice: Be prepared to respond to patients who worry that they have a contagious virus and could be a danger to others. The proper answer, he said, is this: “You don’t have to worry about infecting people. Your tumor is not making the virus, you’re not infectious, and we have the virus on us already.”

For more information about the antibody test, visit merkelcell.org/sero.

Dr. Brownell reported having no relevant disclosures. SDEF and this news organization are owned by the same parent company.

To the Editor:

Mycosis fungoides (MF) is the most common form of primary cutaneous T-cell lymphoma. It has been associated with increased risk for other visceral and hematologic malignancies.¹ Chronic lymphocytic leukemia (CLL) is one of the most common hematologic malignancies. In the United States, a patient’s lifetime risk for CLL is 0.6%. Chronic lymphocytic leukemia often is diagnosed as an incidental finding and typically is not detrimental to a patient’s health. Six cases of MF with antecedent or concomitant CLL were identified in a cohort of patients treated at the University of Minnesota (Minneapolis, Minnesota) from 2005 to 2017 (Table).

All 6 patients were male, with a mean age of 80.5 years. The mean age at CLL diagnosis was 62.5 years, while the mean age at MF diagnosis was 75.3 years. Three patients were younger than 60 years when their CLL was diagnosed: 49, 55, and 57 years. Notably, 4 patients had more aggressive types of MF: 3 with tumor-stage disease, and 1 with folliculotropic MF. Five patients were diagnosed with CLL before their MF was diagnosed (mean, 13.4 years prior; range, 3–31 years), and 1 was diagnosed as part of the initial MF workup.

Given the frequency of both MF and CLL, the co-occurrence of these diseases is not surprising, as other case reports and a larger case series have described the relationship between MF and malignancy.² It is possible that CLL patients are more likely to be diagnosed with MF because of their regular hematology/oncology follow-up; however, none of our patients were referred from hematology/oncology to dermatology. Alternatively, patients with MF may be more likely to be diagnosed with CLL because of repeated bloodwork performed for diagnosis and screening, which occurred in only 1 of 6 cases. Most of the other patients were diagnosed with MF more than a decade after being diagnosed with CLL.

Does having CLL make patients more likely to develop MF? It is known that patients with CLL may experience immunodeficiency secondary to immune dysregulation, making them more susceptible to infection and secondary malignancies.³ Of our 6 cases, 4 had aggressive or advanced forms of MF, which is similar to the findings of Chang et al.² In their report, of 8 patients with MF, 2 had tumor-stage disease and 2 had erythrodermic MF. They determined that these patients had worse overall survival.² Our data corroborate the finding that patients with CLL may develop more severe MF, which leads to the conclusion that patients diagnosed with CLL before, concomitantly, or after their diagnosis of MF should be closely monitored. It is notable that patients with more advanced disease tend to be older at the time of diagnosis and that patients who are diagnosed at 57 years or older have been found to have worse disease-specific survival.^4,5

This report is limited by the small sample size (6 cases), but it serves to draw attention to the phenomenon of co-occurrence of MF and CLL, and the concern that patients with CLL may develop more aggressive MF.

To the Editor:

Mycosis fungoides (MF) is the most common form of primary cutaneous T-cell lymphoma. It has been associated with increased risk for other visceral and hematologic malignancies.¹ Chronic lymphocytic leukemia (CLL) is one of the most common hematologic malignancies. In the United States, a patient’s lifetime risk for CLL is 0.6%. Chronic lymphocytic leukemia often is diagnosed as an incidental finding and typically is not detrimental to a patient’s health. Six cases of MF with antecedent or concomitant CLL were identified in a cohort of patients treated at the University of Minnesota (Minneapolis, Minnesota) from 2005 to 2017 (Table).

All 6 patients were male, with a mean age of 80.5 years. The mean age at CLL diagnosis was 62.5 years, while the mean age at MF diagnosis was 75.3 years. Three patients were younger than 60 years when their CLL was diagnosed: 49, 55, and 57 years. Notably, 4 patients had more aggressive types of MF: 3 with tumor-stage disease, and 1 with folliculotropic MF. Five patients were diagnosed with CLL before their MF was diagnosed (mean, 13.4 years prior; range, 3–31 years), and 1 was diagnosed as part of the initial MF workup.

Given the frequency of both MF and CLL, the co-occurrence of these diseases is not surprising, as other case reports and a larger case series have described the relationship between MF and malignancy.² It is possible that CLL patients are more likely to be diagnosed with MF because of their regular hematology/oncology follow-up; however, none of our patients were referred from hematology/oncology to dermatology. Alternatively, patients with MF may be more likely to be diagnosed with CLL because of repeated bloodwork performed for diagnosis and screening, which occurred in only 1 of 6 cases. Most of the other patients were diagnosed with MF more than a decade after being diagnosed with CLL.

Does having CLL make patients more likely to develop MF? It is known that patients with CLL may experience immunodeficiency secondary to immune dysregulation, making them more susceptible to infection and secondary malignancies.³ Of our 6 cases, 4 had aggressive or advanced forms of MF, which is similar to the findings of Chang et al.² In their report, of 8 patients with MF, 2 had tumor-stage disease and 2 had erythrodermic MF. They determined that these patients had worse overall survival.² Our data corroborate the finding that patients with CLL may develop more severe MF, which leads to the conclusion that patients diagnosed with CLL before, concomitantly, or after their diagnosis of MF should be closely monitored. It is notable that patients with more advanced disease tend to be older at the time of diagnosis and that patients who are diagnosed at 57 years or older have been found to have worse disease-specific survival.^4,5

This report is limited by the small sample size (6 cases), but it serves to draw attention to the phenomenon of co-occurrence of MF and CLL, and the concern that patients with CLL may develop more aggressive MF.

To the Editor:

Mycosis fungoides (MF) is the most common form of primary cutaneous T-cell lymphoma. It has been associated with increased risk for other visceral and hematologic malignancies.¹ Chronic lymphocytic leukemia (CLL) is one of the most common hematologic malignancies. In the United States, a patient’s lifetime risk for CLL is 0.6%. Chronic lymphocytic leukemia often is diagnosed as an incidental finding and typically is not detrimental to a patient’s health. Six cases of MF with antecedent or concomitant CLL were identified in a cohort of patients treated at the University of Minnesota (Minneapolis, Minnesota) from 2005 to 2017 (Table).

All 6 patients were male, with a mean age of 80.5 years. The mean age at CLL diagnosis was 62.5 years, while the mean age at MF diagnosis was 75.3 years. Three patients were younger than 60 years when their CLL was diagnosed: 49, 55, and 57 years. Notably, 4 patients had more aggressive types of MF: 3 with tumor-stage disease, and 1 with folliculotropic MF. Five patients were diagnosed with CLL before their MF was diagnosed (mean, 13.4 years prior; range, 3–31 years), and 1 was diagnosed as part of the initial MF workup.

Given the frequency of both MF and CLL, the co-occurrence of these diseases is not surprising, as other case reports and a larger case series have described the relationship between MF and malignancy.² It is possible that CLL patients are more likely to be diagnosed with MF because of their regular hematology/oncology follow-up; however, none of our patients were referred from hematology/oncology to dermatology. Alternatively, patients with MF may be more likely to be diagnosed with CLL because of repeated bloodwork performed for diagnosis and screening, which occurred in only 1 of 6 cases. Most of the other patients were diagnosed with MF more than a decade after being diagnosed with CLL.

Does having CLL make patients more likely to develop MF? It is known that patients with CLL may experience immunodeficiency secondary to immune dysregulation, making them more susceptible to infection and secondary malignancies.³ Of our 6 cases, 4 had aggressive or advanced forms of MF, which is similar to the findings of Chang et al.² In their report, of 8 patients with MF, 2 had tumor-stage disease and 2 had erythrodermic MF. They determined that these patients had worse overall survival.² Our data corroborate the finding that patients with CLL may develop more severe MF, which leads to the conclusion that patients diagnosed with CLL before, concomitantly, or after their diagnosis of MF should be closely monitored. It is notable that patients with more advanced disease tend to be older at the time of diagnosis and that patients who are diagnosed at 57 years or older have been found to have worse disease-specific survival.^4,5

This report is limited by the small sample size (6 cases), but it serves to draw attention to the phenomenon of co-occurrence of MF and CLL, and the concern that patients with CLL may develop more aggressive MF.

LAS VEGAS – Cases of cutaneous squamous cell carcinoma (cSCC) are on the rise and are associated with mortality rates similar to melanoma. But even as cSCC draws more attention, two popular staging systems still need refinement, a hematologist-oncologist told dermatologist colleagues.

Both staging systems can be helpful, however, Guilherme Rabinowits, MD, said at Skin Disease Education Foundation’s annual Las Vegas Dermatology Seminar. “The best thing to do is combine both,” he noted, referring to the staging system developed by the Brigham and Women’s Hospital (BWH) and staging systems released in the 7th and 8th editions of the American Joint Committee on Cancer Staging Manual (AJCC 7 and AJCC 8; the latter focuses on head and neck only).

Cutaneous SCC has become a “huge health care burden,” said Dr. Rabinowits of the Miami Cancer Institute/Baptist Health South Florida and Florida International University, Miami. He referred to Medicare data suggesting that cSCC has become as common as basal cell carcinoma (JAMA Dermatol. 2015 Oct;151[10]:1081-6).

While most patients with cSCC have a positive prognosis, he added, the 5-year survival rate among those with the most aggressive disease is only 25%.

As he pointed out, staging systems provide insight into prognosis and treatment, guide appropriate monitoring, and give a common language to clinicians around the world. “When I talk about stage 3, we all understand who we’re talking about,” he said.

Dr. Rabinowits said he formerly worked at BWH so he is especially comfortable with its staging system. It can be appropriate to use both the BWH and AJCC systems at once, he said, noting, however, that studies suggest that the BWH system is superior.

An analysis released in 2014, for example, found that most poor outcomes occurred in patients whose tumors had been rated at lower stages – suggesting less risk – in the AJCC 7 system (J Clin Oncol 2014 Feb 1;32[4]:327-4).

In contrast, the 5% of tumors that were rated at the highest stages in the BWH system – with the highest level of perceived risk – accounted for 70% of nodal metastases and 83% of disease-specific deaths. This group may deserve extra attention in terms of staging and adjuvant treatment in order to improve outcomes, he said.

A study published this year, which compared the BWH and AJCC 8 staging systems, found that they had the same negative predictive value (0.99), while the BWH system showed higher positive predictive value (0.30 vs. 0.17). “Use of BWH tumor classification may minimize the number of patients recommended for radiologic evaluation, close surveillance, and possible adjuvant therapy while still identifying most patients at risk for recurrence, metastasis, and death,” the authors wrote (JAMA Dermatol. 2019 Jul 1;155[7]: 819-25).

As for treatment of localized disease in high-risk patients, Dr. Rabinowits advised turning to a multidisciplinary team for guidance because there are limited prospective randomized data.

Dr. Rabinowits discloses scientific advisory board/consultant relationships (Merck, Regeneron, Sanofi, EMD Serono, Pfizer, and Castle) and shares in Regeneron and Syros Pharmaceuticals. He spoke during a forum on cutaneous malignancies at the meeting.

SDEF and this news organization are owned by the same parent company.

LAS VEGAS – Cases of cutaneous squamous cell carcinoma (cSCC) are on the rise and are associated with mortality rates similar to melanoma. But even as cSCC draws more attention, two popular staging systems still need refinement, a hematologist-oncologist told dermatologist colleagues.

Both staging systems can be helpful, however, Guilherme Rabinowits, MD, said at Skin Disease Education Foundation’s annual Las Vegas Dermatology Seminar. “The best thing to do is combine both,” he noted, referring to the staging system developed by the Brigham and Women’s Hospital (BWH) and staging systems released in the 7th and 8th editions of the American Joint Committee on Cancer Staging Manual (AJCC 7 and AJCC 8; the latter focuses on head and neck only).

Cutaneous SCC has become a “huge health care burden,” said Dr. Rabinowits of the Miami Cancer Institute/Baptist Health South Florida and Florida International University, Miami. He referred to Medicare data suggesting that cSCC has become as common as basal cell carcinoma (JAMA Dermatol. 2015 Oct;151[10]:1081-6).

While most patients with cSCC have a positive prognosis, he added, the 5-year survival rate among those with the most aggressive disease is only 25%.

As he pointed out, staging systems provide insight into prognosis and treatment, guide appropriate monitoring, and give a common language to clinicians around the world. “When I talk about stage 3, we all understand who we’re talking about,” he said.

Dr. Rabinowits said he formerly worked at BWH so he is especially comfortable with its staging system. It can be appropriate to use both the BWH and AJCC systems at once, he said, noting, however, that studies suggest that the BWH system is superior.

An analysis released in 2014, for example, found that most poor outcomes occurred in patients whose tumors had been rated at lower stages – suggesting less risk – in the AJCC 7 system (J Clin Oncol 2014 Feb 1;32[4]:327-4).

In contrast, the 5% of tumors that were rated at the highest stages in the BWH system – with the highest level of perceived risk – accounted for 70% of nodal metastases and 83% of disease-specific deaths. This group may deserve extra attention in terms of staging and adjuvant treatment in order to improve outcomes, he said.

A study published this year, which compared the BWH and AJCC 8 staging systems, found that they had the same negative predictive value (0.99), while the BWH system showed higher positive predictive value (0.30 vs. 0.17). “Use of BWH tumor classification may minimize the number of patients recommended for radiologic evaluation, close surveillance, and possible adjuvant therapy while still identifying most patients at risk for recurrence, metastasis, and death,” the authors wrote (JAMA Dermatol. 2019 Jul 1;155[7]: 819-25).

As for treatment of localized disease in high-risk patients, Dr. Rabinowits advised turning to a multidisciplinary team for guidance because there are limited prospective randomized data.

Dr. Rabinowits discloses scientific advisory board/consultant relationships (Merck, Regeneron, Sanofi, EMD Serono, Pfizer, and Castle) and shares in Regeneron and Syros Pharmaceuticals. He spoke during a forum on cutaneous malignancies at the meeting.

SDEF and this news organization are owned by the same parent company.

LAS VEGAS – Cases of cutaneous squamous cell carcinoma (cSCC) are on the rise and are associated with mortality rates similar to melanoma. But even as cSCC draws more attention, two popular staging systems still need refinement, a hematologist-oncologist told dermatologist colleagues.

Both staging systems can be helpful, however, Guilherme Rabinowits, MD, said at Skin Disease Education Foundation’s annual Las Vegas Dermatology Seminar. “The best thing to do is combine both,” he noted, referring to the staging system developed by the Brigham and Women’s Hospital (BWH) and staging systems released in the 7th and 8th editions of the American Joint Committee on Cancer Staging Manual (AJCC 7 and AJCC 8; the latter focuses on head and neck only).

Cutaneous SCC has become a “huge health care burden,” said Dr. Rabinowits of the Miami Cancer Institute/Baptist Health South Florida and Florida International University, Miami. He referred to Medicare data suggesting that cSCC has become as common as basal cell carcinoma (JAMA Dermatol. 2015 Oct;151[10]:1081-6).

While most patients with cSCC have a positive prognosis, he added, the 5-year survival rate among those with the most aggressive disease is only 25%.

As he pointed out, staging systems provide insight into prognosis and treatment, guide appropriate monitoring, and give a common language to clinicians around the world. “When I talk about stage 3, we all understand who we’re talking about,” he said.

Dr. Rabinowits said he formerly worked at BWH so he is especially comfortable with its staging system. It can be appropriate to use both the BWH and AJCC systems at once, he said, noting, however, that studies suggest that the BWH system is superior.

An analysis released in 2014, for example, found that most poor outcomes occurred in patients whose tumors had been rated at lower stages – suggesting less risk – in the AJCC 7 system (J Clin Oncol 2014 Feb 1;32[4]:327-4).

In contrast, the 5% of tumors that were rated at the highest stages in the BWH system – with the highest level of perceived risk – accounted for 70% of nodal metastases and 83% of disease-specific deaths. This group may deserve extra attention in terms of staging and adjuvant treatment in order to improve outcomes, he said.

A study published this year, which compared the BWH and AJCC 8 staging systems, found that they had the same negative predictive value (0.99), while the BWH system showed higher positive predictive value (0.30 vs. 0.17). “Use of BWH tumor classification may minimize the number of patients recommended for radiologic evaluation, close surveillance, and possible adjuvant therapy while still identifying most patients at risk for recurrence, metastasis, and death,” the authors wrote (JAMA Dermatol. 2019 Jul 1;155[7]: 819-25).

As for treatment of localized disease in high-risk patients, Dr. Rabinowits advised turning to a multidisciplinary team for guidance because there are limited prospective randomized data.

Dr. Rabinowits discloses scientific advisory board/consultant relationships (Merck, Regeneron, Sanofi, EMD Serono, Pfizer, and Castle) and shares in Regeneron and Syros Pharmaceuticals. He spoke during a forum on cutaneous malignancies at the meeting.

SDEF and this news organization are owned by the same parent company.

LAS VEGAS – For patients with nonchallenging cases of basal cell carcinoma, surgery remains the gold standard of treatment, but imiquimod is another feasible option, according to Ervin H. Epstein, MD.

Doug Brunk/MDedge News

In a noninferiority trial, researchers in the Netherlands randomized 601 patients with superficial BCCs to one of three medical treatments: two treatments of photodynamic therapy (PDT) 1 week apart (group 1), imiquimod 5 days per week for 6 weeks with no occlusion (group 2), and 5-fluorouracil (5-FU) twice per day for 4 weeks with no occlusion (group 3). They followed the patients for 5 years to see which tumors came back (J Invest Dermatol. 2018 Mar;138[3]:527-33). At 5 years, tumor-free survival was 63% in group 1, 81% in group 2, and 70% in group 3. Based on this analysis the authors concluded that imiquimod is the first choice for noninvasive treatment of most primary BCCs.

“Yes, imiquimod is helpful, but it’s not as good as surgery,” Dr. Epstein said at the Skin Disease Education Foundation’s annual Las Vegas Dermatology Seminar.

Researchers like Dr. Epstein, a dermatologist at Brown & Toland Physicians in Oakland, Calif., have been exploring ways to reduce the recurrence of BCCs in those at high risk. One approach is to stay out of the sun, but that is not practical for most people, “and the data are not very supportive,” he said. “Very few people can actually avoid sunlight. What about topical 5-FU? Suppose you put on 5-FU and then study people for the next year, to see what the likelihood is of them getting a BCC? Why it has taken us so long to do this kind of study is in some ways shameful.” He mentioned one study in which patients at risk of superficial BCC recurrence applied topical 5-FU twice a day for 2-4 weeks. The regimen led to an 11% decrease in the development of BCCs, a trend that did not reach statistical significance.

Another approach to warding off BCC recurrence is to take oral hedgehog pathway inhibitors, which are highly effective. “The problem is, hedgehog pathway inhibitors have side effects that are not catastrophic, but they’re annoying,” Dr. Epstein said. “Patients can lose their hair, they get muscle cramps, and can lose their taste.”

To date, there have been at least three trials evaluating the feasibility of a topical hedgehog pathway inhibitor in adult subjects. In one of the trials, researchers evaluated the efficacy of LDE225, a selective antagonist of Smoothened, in eight patients with nevoid basal cell carcinoma syndrome. They were instructed to apply LDE225 twice per day for 4 weeks (J Invest Dermatol 2011 Aug;131[8]:1735-44). Of 13 BCCs treated in the patients, 12 had a partial to complete response. In fact, eight BCCs had an average of 56% volume reduction but none had complete histologic clearing.

At PellePharm, a biotechnology that Dr. Epstein cofounded, researchers are developing patidegib topical gel, 2%, for the reduction of disease burden of persistently developing BCCs in subjects with Gorlin syndrome. In a phase 3 trial, which just completed recruitment, adults are instructed to apply the gel twice daily to the face for 12 months. The primary endpoint is a comparison between the two treatment arms of the number of new surgically eligible BCCs that develop over the 12-month period. “We want to see if we can reduce the number of surgically eligible BCCs,” Dr. Epstein said. “We’re very hopeful.”

SDEF and this news organization are owned by the same parent company. Dr. Epstein spoke during a forum on cutaneous malignancies at the meeting.

Dr. Epstein disclosed that he has been a consultant for Genentech, Novartis, Amgen, and Infinity. He is also cofounder/director and stockholder in PellePharm.

[email protected]

LAS VEGAS – For patients with nonchallenging cases of basal cell carcinoma, surgery remains the gold standard of treatment, but imiquimod is another feasible option, according to Ervin H. Epstein, MD.

Doug Brunk/MDedge News

In a noninferiority trial, researchers in the Netherlands randomized 601 patients with superficial BCCs to one of three medical treatments: two treatments of photodynamic therapy (PDT) 1 week apart (group 1), imiquimod 5 days per week for 6 weeks with no occlusion (group 2), and 5-fluorouracil (5-FU) twice per day for 4 weeks with no occlusion (group 3). They followed the patients for 5 years to see which tumors came back (J Invest Dermatol. 2018 Mar;138[3]:527-33). At 5 years, tumor-free survival was 63% in group 1, 81% in group 2, and 70% in group 3. Based on this analysis the authors concluded that imiquimod is the first choice for noninvasive treatment of most primary BCCs.

“Yes, imiquimod is helpful, but it’s not as good as surgery,” Dr. Epstein said at the Skin Disease Education Foundation’s annual Las Vegas Dermatology Seminar.

Researchers like Dr. Epstein, a dermatologist at Brown & Toland Physicians in Oakland, Calif., have been exploring ways to reduce the recurrence of BCCs in those at high risk. One approach is to stay out of the sun, but that is not practical for most people, “and the data are not very supportive,” he said. “Very few people can actually avoid sunlight. What about topical 5-FU? Suppose you put on 5-FU and then study people for the next year, to see what the likelihood is of them getting a BCC? Why it has taken us so long to do this kind of study is in some ways shameful.” He mentioned one study in which patients at risk of superficial BCC recurrence applied topical 5-FU twice a day for 2-4 weeks. The regimen led to an 11% decrease in the development of BCCs, a trend that did not reach statistical significance.

Another approach to warding off BCC recurrence is to take oral hedgehog pathway inhibitors, which are highly effective. “The problem is, hedgehog pathway inhibitors have side effects that are not catastrophic, but they’re annoying,” Dr. Epstein said. “Patients can lose their hair, they get muscle cramps, and can lose their taste.”

To date, there have been at least three trials evaluating the feasibility of a topical hedgehog pathway inhibitor in adult subjects. In one of the trials, researchers evaluated the efficacy of LDE225, a selective antagonist of Smoothened, in eight patients with nevoid basal cell carcinoma syndrome. They were instructed to apply LDE225 twice per day for 4 weeks (J Invest Dermatol 2011 Aug;131[8]:1735-44). Of 13 BCCs treated in the patients, 12 had a partial to complete response. In fact, eight BCCs had an average of 56% volume reduction but none had complete histologic clearing.

At PellePharm, a biotechnology that Dr. Epstein cofounded, researchers are developing patidegib topical gel, 2%, for the reduction of disease burden of persistently developing BCCs in subjects with Gorlin syndrome. In a phase 3 trial, which just completed recruitment, adults are instructed to apply the gel twice daily to the face for 12 months. The primary endpoint is a comparison between the two treatment arms of the number of new surgically eligible BCCs that develop over the 12-month period. “We want to see if we can reduce the number of surgically eligible BCCs,” Dr. Epstein said. “We’re very hopeful.”

SDEF and this news organization are owned by the same parent company. Dr. Epstein spoke during a forum on cutaneous malignancies at the meeting.

Dr. Epstein disclosed that he has been a consultant for Genentech, Novartis, Amgen, and Infinity. He is also cofounder/director and stockholder in PellePharm.

[email protected]

LAS VEGAS – For patients with nonchallenging cases of basal cell carcinoma, surgery remains the gold standard of treatment, but imiquimod is another feasible option, according to Ervin H. Epstein, MD.

Doug Brunk/MDedge News

In a noninferiority trial, researchers in the Netherlands randomized 601 patients with superficial BCCs to one of three medical treatments: two treatments of photodynamic therapy (PDT) 1 week apart (group 1), imiquimod 5 days per week for 6 weeks with no occlusion (group 2), and 5-fluorouracil (5-FU) twice per day for 4 weeks with no occlusion (group 3). They followed the patients for 5 years to see which tumors came back (J Invest Dermatol. 2018 Mar;138[3]:527-33). At 5 years, tumor-free survival was 63% in group 1, 81% in group 2, and 70% in group 3. Based on this analysis the authors concluded that imiquimod is the first choice for noninvasive treatment of most primary BCCs.

“Yes, imiquimod is helpful, but it’s not as good as surgery,” Dr. Epstein said at the Skin Disease Education Foundation’s annual Las Vegas Dermatology Seminar.

Researchers like Dr. Epstein, a dermatologist at Brown & Toland Physicians in Oakland, Calif., have been exploring ways to reduce the recurrence of BCCs in those at high risk. One approach is to stay out of the sun, but that is not practical for most people, “and the data are not very supportive,” he said. “Very few people can actually avoid sunlight. What about topical 5-FU? Suppose you put on 5-FU and then study people for the next year, to see what the likelihood is of them getting a BCC? Why it has taken us so long to do this kind of study is in some ways shameful.” He mentioned one study in which patients at risk of superficial BCC recurrence applied topical 5-FU twice a day for 2-4 weeks. The regimen led to an 11% decrease in the development of BCCs, a trend that did not reach statistical significance.

Another approach to warding off BCC recurrence is to take oral hedgehog pathway inhibitors, which are highly effective. “The problem is, hedgehog pathway inhibitors have side effects that are not catastrophic, but they’re annoying,” Dr. Epstein said. “Patients can lose their hair, they get muscle cramps, and can lose their taste.”

To date, there have been at least three trials evaluating the feasibility of a topical hedgehog pathway inhibitor in adult subjects. In one of the trials, researchers evaluated the efficacy of LDE225, a selective antagonist of Smoothened, in eight patients with nevoid basal cell carcinoma syndrome. They were instructed to apply LDE225 twice per day for 4 weeks (J Invest Dermatol 2011 Aug;131[8]:1735-44). Of 13 BCCs treated in the patients, 12 had a partial to complete response. In fact, eight BCCs had an average of 56% volume reduction but none had complete histologic clearing.

At PellePharm, a biotechnology that Dr. Epstein cofounded, researchers are developing patidegib topical gel, 2%, for the reduction of disease burden of persistently developing BCCs in subjects with Gorlin syndrome. In a phase 3 trial, which just completed recruitment, adults are instructed to apply the gel twice daily to the face for 12 months. The primary endpoint is a comparison between the two treatment arms of the number of new surgically eligible BCCs that develop over the 12-month period. “We want to see if we can reduce the number of surgically eligible BCCs,” Dr. Epstein said. “We’re very hopeful.”

SDEF and this news organization are owned by the same parent company. Dr. Epstein spoke during a forum on cutaneous malignancies at the meeting.

Dr. Epstein disclosed that he has been a consultant for Genentech, Novartis, Amgen, and Infinity. He is also cofounder/director and stockholder in PellePharm.

[email protected]

Dermatologists are increasingly called on to evaluate patients with complex medical problems who are often taking many medications. Over the last several decades, many new drugs that target molecular pathways in carcinogenesis and the inflammatory immune system have been developed. Increased skin cancer risk has been reported in association with BRAF inhibitors, sonic hedgehog–inhibiting agents, Janus kinase (JAK) inhibitors, and phosphodiesterase 5 (PDE-5) inhibitors. We review the literature and data regarding the significance and strength of these associations and the molecular pathways by which these medications promote cutaneous tumorigenesis. The association of skin cancer with drugs that either induce photosensitivity—nonsteroidal anti-inflammatory drugs, antibiotics (eg, tetracyclines, fluoroquinolones, trimethoprim-sulfamethoxazole), voriconazole, thiazides—or suppress the immune system—certain biologics (eg, anti–tumor necrosis factor agents), calcineurin inhibitors, thiopurines, methotrexate, cyclosporine—is well known and is therefore not reviewed in this discussion.

BRAF Inhibitors

The mitogen-activated protein kinase (MAPK) pathway (also known as the RAS/RAF/MAPK signaling pathway) is important in growth factor–receptor signaling and plays a key role in cell differentiation, survival, and proliferation. Activating mutations in this pathway allow cells to grow and proliferate in a growth factor–independent manner. Twenty percent of human cancers harbor a mutation in the RAS oncogene, an upstream mediator of the pathway.¹ Activating mutations in BRAF, a serine/threonine kinase, predominate in cutaneous melanoma and also have been found in 40% to 70% of papillary thyroid malignancies, 10% to 20% of cholangiocarcinomas, and 5% to 20% of colorectal carcinomas. The most common BRAF mutation in cutaneous melanoma is V600E, which involves a glutamic acid for valine substitution at codon 600. This mutation activates BRAF 500-fold and is present in approximately 50% of melanomas.^1,2

Vemurafenib, a selective BRAF inhibitor, was approved by the US Food and Drug Administration (FDA) for the treatment of metastatic melanoma in the United States in 2011. Phase 3 trial data demonstrated that vemurafenib resulted in improved survival and decreased risk for disease progression compared to dacarbazine, the former best treatment.³ During phase 1 testing, it became apparent that vemurafenib treatment was associated with a 31% increased risk for squamous cell carcinoma (SCC), most commonly well-differentiated SCC, and keratoacanthomas (KAs).⁴ This association was confirmed in phase 2 and 3 studies, though the incidence was lower. McArthur et al⁵ reported a 19% incidence of cutaneous SCC with extended follow-up analysis of the phase 3 trial. Dabrafenib, another BRAF inhibitor, has been similarly associated with increasing the risk for SCC and KA.

In one study, the mean time to development of SCC after initiating vemurafenib therapy was 10 weeks, with lesions reported as early as 3 weeks. Most patients had clinical signs of chronically sun damaged skin; however, a history of SCC was present in only 17%. Most lesions (63%) were characterized as KAs.⁶

The mechanism for BRAF inhibitor–induced squamoproliferative growth is due to paradoxical activation of the MAPK pathway in cells with wild-type BRAF that harbor upstream-activating mutations in RAS or tyrosine kinase receptors.⁷ In the presence of a BRAF inhibitor, inactivated BRAF forms heterodimers with wild-type CRAF (a BRAF-CRAF heterodimer). The heterodimer forms a complex with the mutant RAS that leads to transactivation of the CRAF molecule,^8,9 resulting in a paradoxical increase in MAPK signaling and consequent ERK phosphorylation and activation through CRAF signaling. RAS, particularly HRAS, mutations have been found in 60% of all vemurafenib-associated SCCs and KAs. For this reason, it is thought that vemurafenib potentiates tumorigenesis in subclinical lesions harboring upstream MAPK pathway mutations as opposed to inducing de novo lesions.⁶

Because BRAF inhibitors are remarkably efficacious in the treatment of metastatic melanomas harboring the V600E BRAF mutation, there are no restrictions on their use, despite the known increased risk for SCC. Squamous cell carcinomas tend to be low grade, and all tumors that developed in phase 1 to 3 trials were treated with simple excision. The development of SCC did not necessitate interruption of treatment. Furthermore, the addition of MEK inhibition to BRAF inhibitor therapy reduces the risk for SCC from 19% to 7%.^7,10,11

In addition to SCC, second primary melanomas (SPMs) have been reported in patients treated with BRAF inhibitors. It has been shown that these melanomas occur in melanocytes with wild-type BRAF. It has been postulated that some of these tumors occur in cells that harbor upstream mutations in RAS, whereas others might result from alternate signaling through non-RAF oncogenic pathways.^9,12

Zimmer et al¹ reported 12 SPMs in 11 patients treated with BRAF inhibitor therapy. They reported a median delay of 8 weeks (range, 4–27 weeks) for SPM development. Tumors were detected in early stages; 1 tumor harbored an NRAS mutation.¹

Dalle et al¹³ reported 25 SPMs in 120 vemurafenib-treated patients. Median delay in SPM development was 14 weeks (range, 4–42 weeks). All tumors were thin, ranging from in situ to 0.45-mm thick. Wild-type BRAF was detected in the 21 melanomas sampled; 1 lesion showed mutated NRAS.¹³

The exact incidence of SPM in the setting of BRAF inhibition is thought to be at least 10-fold less than SCC and KA.² Patients on BRAF inhibitor therapy should have routine full-body skin examinations, given the increased risk for SPM and SCC.

Another drug belonging to the tyrosine kinase inhibitor family, sorafenib, is used in the treatment of solid tumors, particularly hepatocellular and renal cell carcinomas, and also has been associated with development of cutaneous SCC and KAs.¹⁴ Sorafenib is a multiple tyrosine kinase inhibitor that also inhibits the RAF serine/threonine kinases. Similar to vemurafenib and dabrafenib, SCCs and KAs associated with sorafenib tend to arise in patients with chronic actinic damage during the first 2 months of treatment. It has been hypothesized that inhibition of RAF kinases is pathogenic in inducing SCCs because these lesions have not been reported with sunitinib, another multiple tyrosine kinase inhibitor that lacks the ability to inhibit serine/threonine kinases.^15,16 Although SCCs and KAs associated with sorafenib tend to be low grade, it is reasonable to consider sunitinib or an alternative tyrosine kinase inhibitor in patients who develop multiple SCCs while taking sorafenib.¹⁶

Sonic Hedgehog–Inhibiting Agents

Vismodegib, the first small molecule inhibitor of the signaling protein smoothened, gained FDA approval for the treatment of metastatic or locally advanced basal cell carcinoma (BCC) in 2012. A second agent with an identical mechanism of action, sonidegib, was approved by the FDA for locally advanced BCC in 2015. Approximately 90% of BCCs contain mutations in the sonic hedgehog pathway, which lead to constitutive smoothened activation and uncontrolled cell proliferation.¹⁷ The development of smoothened inhibitors introduced a much-needed treatment for inoperable or metastatic BCC,^17,18 though long-term utility is limited by drug resistance with extended use in this patient population.^19,20 Several case reports have documented the emergence of KA²¹ and cutaneous SCC following vismodegib treatment of advanced or metastatic BCC.^22-24 A larger case-control study by Mohan et al²⁵ showed that patients with BCC treated with vismodegib had an increased risk for non-BCC malignancy (hazard ratio [HR]=6.37), most of which were cutaneous SCC (HR=8.12).

The mechanism by which selective inhibition of smoothened leads to cutaneous SCC is unclear. A study found that patients on vismodegib who developed SCC within the original BCC site had elevated ERK levels within tumor tissue, suggesting that the RAS/RAF/MAPK pathway can become upregulated during hedgehog inhibition.²⁶ Other studies looking at hedgehog inhibition in medulloblastoma models also have shown activated RAS/RAF/MAPK pathways.²⁵ These findings suggest that tumors under smoothened inhibition might be able to bypass the sonic hedgehog pathway and continue to grow by upregulating alternative growth pathways, such as RAS/RAF/MAPK.^25,26

The incidence of cutaneous SCC following vismodegib treatment is unknown. Chang and Oro²⁷ examined BCC tumor regrowth from secondary (acquired) resistance to vismodegib and noted that lesions recurred within 1 cm of the original tumor 21% of the time. Although none of the 12 patients whose tumors regrew during treatment were reported to have developed SCC, several demonstrated different BCC subtypes than the pretreatment specimen. The authors proposed that regrowth of BCC was due to upregulated alternative pathways allowing tumors to bypass smoothened inhibition, which is similar to the proposed mechanism for SCC development in vismodegib patients.²⁷

Prospective studies are needed to confirm the link between vismodegib and cutaneous SCC; establish the incidence of SCC development; and identify any pretreatment factors, tumor characteristics, or treatment details (eg, dosage, duration) that might contribute to SCC development. Furthermore, because Mohan et al²⁵ observed that vismodegib-treated patients were less likely to develop SCC in situ than controls, it is unknown if these tumors are more aggressive than traditional SCC. At this point, careful surveillance and regular full-body skin examinations are advised for patients on vismodegib for treatment of advanced BCC.

JAK Inhibitors

Another class of medications potentially associated with increased development of nonmelanoma skin cancer (NMSC) is the JAK inhibitors (also known as jakinibs). Many proinflammatory signaling pathways converge on the JAK family of enzymes—JAK1, JAK2, JAK3, and TYK2. These enzymes operate in cytokine signal transduction by phosphorylating activated cytokine receptors, which allows for recruitment and activation by means of phosphorylation of transcription factors collectively known as signal transducers and activators of transcription (STATs). Phosphorylated STATs dimerize and translocate to the nucleus, acting as direct transcription promoters. Janus kinase inhibitors modulate the immune response by reducing the effect of interleukin and interferon signaling.

Ruxolitinib, a JAK1/JAK2 inhibitor, was the first JAK inhibitor approved by the FDA and is indicated for the treatment of myelofibrosis and polycythemia vera. Additionally, oral and topical JAK inhibitors have shown efficacy in the treatment of psoriasis, rheumatoid arthritis, alopecia areata, vitiligo, and pruritus from atopic dermatitis.²⁸

The JAK-STAT pathway is complex, and the biological activity of the pathway is both proinflammatory and pro–cell survival and proliferation. Because signaling through the pathway can increase angiogenesis and inhibit apoptosis, inhibition of this pathway has been exploited for the treatment of some tumors. However, inhibition of interferon and proinflammatory interleukin signaling also can potentially promote tumor growth by means of inhibition of downstream cytotoxic T-cell signaling, theoretically increasing the risk for NMSC. A study examining the 5-year efficacy of ruxolitinib in myelofibrosis patients (COMFORT-II trial) found that 17.1% of patients developed NMSC compared to only 2.7% of those on the best available therapy. After adjustment by patient exposure, the NMSC rate was still doubled for ruxolitinib-treated patients compared to controls (6.1/100 patient-years and 3.0/100 patient-years, respectively).²⁹ Eighty-week follow-up of the phase 3 clinical trial of ruxolitinib for the treatment of polycythemia vera also noted an increased incidence of NMSC, albeit a more conservative increase. Patients randomized to the ruxolitinib treatment group developed NMSC at a rate of 4.4/100 patient-years, whereas the rate for controls treated with best available therapy was 2.7/100 patient-years.³⁰ In contrast, 5-year follow-up of the COMFORT-I trial, also examining the efficacy of ruxolitinib in myelofibrosis, showed no increased risk for NMSC between ruxolitinib-treated patients and placebo (2.7/100 patient-years and 3.9/100 patient-years, respectively).³¹

A 2017 case series described 5 patients with myelofibrosis who developed multiple skin cancers with aggressive features while receiving ruxolitinib.³² Duration of ruxolitinib therapy ranged from 4 months to 4 years; 3 patients had a history of hydroxyurea exposure, and only 1 patient had a history of NMSC. High-risk cutaneous SCC, undifferentiated pleomorphic sarcoma, and lentigo maligna melanoma (Breslow thickness, 0.45 mm) were among the tumors reported in this series. Although no definitive conclusion can be made regarding the causality of JAK inhibitors in promoting these tumors, the association warrants further investigation. Clinicians should be aware that ruxolitinib might amplify the risk for NMSC in patients with pre-existing genetic or exposure-related susceptibility. Interruption of drug therapy may be necessary in managing patients who develop an aggressive tumor.³²

In contrast, tofacitinib, which specifically inhibits JAK3, carries very low risk, if any, for NMSC when used for the treatment of psoriasis and rheumatoid arthritis. Results from 2 phase 3 trials analyzing the efficacy of tofacitinib in psoriasis demonstrated that only 2 of 1486 patients treated developed NMSC compared to none in the control group.³³ Furthermore, analysis of NMSC across the tofacitinib rheumatoid arthritis clinical program, which included a total of 15,103 patient-years of exposure, demonstrated that the overall NMSC incidence was 0.55 for every 100 patient-years. Of note, the risk in patients receiving high-dose treatment (10 mg vs 5 mg) was nearly doubled in long-term follow-up studies (0.79/100 patient-years and 0.41/100 patient-years, respectively). Overall, the study concluded that treatment with tofacitinib presents no greater increased risk for NMSC than treatment with tumor necrosis factor inhibitors.³³

PDE-5 Inhibitors

Phosphodiesterase 5 inhibitors, such as sildenafil citrate, have been widely prescribed for the treatment of erectile dysfunction. Studies have shown that BRAF-activated melanomas, which occur in approximately 50% to 70% of melanomas, also result in reduced PDE-5 expression.^34-36 In these melanomas, downregulation of PDE-5 results in increased intracellular calcium,³⁶ which has been shown to induce melanoma invasion.^36,37 Given this similarity in molecular pathway between BRAF-activated melanomas and PDE-5 inhibitors, there has been increased concern that PDE-5 inhibitors might be associated with an increased risk for melanoma.

In 2014, Li et al³⁸ published a retrospective analysis suggesting an association with sildenafil and an increased risk for melanoma. Their study utilized the Health Professionals Follow-up Study to identify a statistically significant elevation in the risk for invasive melanoma with both recent sildenafil use (multivariate-adjusted HR=2.24) and use at any time (HR=1.92). These results controlled for confounding variables, such as presence of major chronic disease, use of other erectile dysfunction treatments, family history of melanoma, history of sun exposure, and UV index of the patient’s residence. Notably, the study also found that sildenafil did not affect the incidence of BCC or SCC.³⁸

In 2015, Loeb et al³⁹ also examined the potential association between PDE-5 inhibitors and melanoma. Review of several Swedish drug and cancer registries allowed for analysis of melanoma risk and PDE-5 inhibitor use, based on number of prescriptions filled and type of PDE-5 inhibitor prescribed. Their analysis showed that men developing melanoma were more likely than nonmelanoma controls to have taken a PDE-5 inhibitor (11% vs 8%). In a subgroup analysis, however, statistical significance was shown for men with only a single prescription filled (34% of cases; P<.05), whereas the difference for men with multiple filled prescriptions did not meet statistical significance. Furthermore, the study did not find increased risk with longer-acting tadalafil and vardenafil (odds ratio [OR]=1.16) compared to sildenafil (OR=1.14). Last, use of PDE-5 inhibitors was only associated with stage 0 (OR=1.49) and stage I (OR=1.21) tumors, not with stages II to IV (OR=0.83) tumors. Although there was a statistically significant association between PDE-5 inhibitors and malignant melanoma (P<.05), the subgroup analysis findings pointed away from a causal relationship and likely toward a confounding of variable(s).³⁹

A 2016 study by Lian et al⁴⁰ looked at the risk for melanoma in a cohort of patients diagnosed with erectile dysfunction. No association between PDE-5 inhibitors and melanoma risk was shown when comparing patients who received a PDE-5 inhibitor and those who did not receive a PDE-5 inhibitor. However, secondary analysis did show that melanoma risk was increased among patients receiving more pills (34%) and prescriptions (30%). The authors concluded that there was no association between PDE-5 inhibitor use and overall increased risk for melanoma, and the increased risk associated with a greater number of pills and prescriptions would require further study.⁴⁰

In contrast, a 2017 meta-analysis by Tang et al⁴¹ of 5 studies (3 of which were the aforementioned trials^38-40) concluded that use of PDE-5 inhibitors was associated with a small but significantly increased risk for melanoma (OR=1.12) and BCC (OR=1.14) but not SCC. Furthermore, the study found no evidence of dosage-dependent association between PDE-5 inhibitor use and melanoma risk.⁴¹

Overall, clinical studies have been inconclusive in determining the risk for melanoma in the setting of PDE-5 inhibitor use. Studies showing an increased rate of melanoma within patient cohorts receiving PDE-5 inhibitors are limited; results might be affected by confounding variables. However, given the similarity in mechanism between PDE-5 inhibitors and HRAS-activated melanomas, it is reasonable to continue research into this potential association.

Conclusion

Since the turn of the century, drugs targeting cell-signaling pathways have been developed to treat inflammatory, oncologic, and immune conditions. The role of immunosuppressants in promoting skin cancer is well established and supported by a vast literature base. However, associations are less clear with newer immunomodulatory and antineoplastic medications. Skin cancer has been reported in association with BRAF inhibitors, sonic hedgehog–inhibiting agents, JAK inhibitors, and PDE-5 inhibitors. In the case of JAK and PDE-5 inhibitors, the increased risk for melanoma and NMSC is somewhat inconclusive; risk is more firmly established for BRAF inhibitors and smoothened inhibitors. For the antineoplastic agents reviewed, the therapeutic effect of cancer regression is well documented, and benefits of continued therapy outweigh the increased risk for skin cancer promotion in nearly all cases. The value of early detection has been well documented for skin malignancy; therefore, increased skin surveillance and prompt management of suspicious lesions should be a priority for physicians treating patients undergoing therapy with these medications

Dermatologists are increasingly called on to evaluate patients with complex medical problems who are often taking many medications. Over the last several decades, many new drugs that target molecular pathways in carcinogenesis and the inflammatory immune system have been developed. Increased skin cancer risk has been reported in association with BRAF inhibitors, sonic hedgehog–inhibiting agents, Janus kinase (JAK) inhibitors, and phosphodiesterase 5 (PDE-5) inhibitors. We review the literature and data regarding the significance and strength of these associations and the molecular pathways by which these medications promote cutaneous tumorigenesis. The association of skin cancer with drugs that either induce photosensitivity—nonsteroidal anti-inflammatory drugs, antibiotics (eg, tetracyclines, fluoroquinolones, trimethoprim-sulfamethoxazole), voriconazole, thiazides—or suppress the immune system—certain biologics (eg, anti–tumor necrosis factor agents), calcineurin inhibitors, thiopurines, methotrexate, cyclosporine—is well known and is therefore not reviewed in this discussion.

BRAF Inhibitors

The mitogen-activated protein kinase (MAPK) pathway (also known as the RAS/RAF/MAPK signaling pathway) is important in growth factor–receptor signaling and plays a key role in cell differentiation, survival, and proliferation. Activating mutations in this pathway allow cells to grow and proliferate in a growth factor–independent manner. Twenty percent of human cancers harbor a mutation in the RAS oncogene, an upstream mediator of the pathway.¹ Activating mutations in BRAF, a serine/threonine kinase, predominate in cutaneous melanoma and also have been found in 40% to 70% of papillary thyroid malignancies, 10% to 20% of cholangiocarcinomas, and 5% to 20% of colorectal carcinomas. The most common BRAF mutation in cutaneous melanoma is V600E, which involves a glutamic acid for valine substitution at codon 600. This mutation activates BRAF 500-fold and is present in approximately 50% of melanomas.^1,2

Vemurafenib, a selective BRAF inhibitor, was approved by the US Food and Drug Administration (FDA) for the treatment of metastatic melanoma in the United States in 2011. Phase 3 trial data demonstrated that vemurafenib resulted in improved survival and decreased risk for disease progression compared to dacarbazine, the former best treatment.³ During phase 1 testing, it became apparent that vemurafenib treatment was associated with a 31% increased risk for squamous cell carcinoma (SCC), most commonly well-differentiated SCC, and keratoacanthomas (KAs).⁴ This association was confirmed in phase 2 and 3 studies, though the incidence was lower. McArthur et al⁵ reported a 19% incidence of cutaneous SCC with extended follow-up analysis of the phase 3 trial. Dabrafenib, another BRAF inhibitor, has been similarly associated with increasing the risk for SCC and KA.

In one study, the mean time to development of SCC after initiating vemurafenib therapy was 10 weeks, with lesions reported as early as 3 weeks. Most patients had clinical signs of chronically sun damaged skin; however, a history of SCC was present in only 17%. Most lesions (63%) were characterized as KAs.⁶

The mechanism for BRAF inhibitor–induced squamoproliferative growth is due to paradoxical activation of the MAPK pathway in cells with wild-type BRAF that harbor upstream-activating mutations in RAS or tyrosine kinase receptors.⁷ In the presence of a BRAF inhibitor, inactivated BRAF forms heterodimers with wild-type CRAF (a BRAF-CRAF heterodimer). The heterodimer forms a complex with the mutant RAS that leads to transactivation of the CRAF molecule,^8,9 resulting in a paradoxical increase in MAPK signaling and consequent ERK phosphorylation and activation through CRAF signaling. RAS, particularly HRAS, mutations have been found in 60% of all vemurafenib-associated SCCs and KAs. For this reason, it is thought that vemurafenib potentiates tumorigenesis in subclinical lesions harboring upstream MAPK pathway mutations as opposed to inducing de novo lesions.⁶

Because BRAF inhibitors are remarkably efficacious in the treatment of metastatic melanomas harboring the V600E BRAF mutation, there are no restrictions on their use, despite the known increased risk for SCC. Squamous cell carcinomas tend to be low grade, and all tumors that developed in phase 1 to 3 trials were treated with simple excision. The development of SCC did not necessitate interruption of treatment. Furthermore, the addition of MEK inhibition to BRAF inhibitor therapy reduces the risk for SCC from 19% to 7%.^7,10,11

In addition to SCC, second primary melanomas (SPMs) have been reported in patients treated with BRAF inhibitors. It has been shown that these melanomas occur in melanocytes with wild-type BRAF. It has been postulated that some of these tumors occur in cells that harbor upstream mutations in RAS, whereas others might result from alternate signaling through non-RAF oncogenic pathways.^9,12

Zimmer et al¹ reported 12 SPMs in 11 patients treated with BRAF inhibitor therapy. They reported a median delay of 8 weeks (range, 4–27 weeks) for SPM development. Tumors were detected in early stages; 1 tumor harbored an NRAS mutation.¹

Dalle et al¹³ reported 25 SPMs in 120 vemurafenib-treated patients. Median delay in SPM development was 14 weeks (range, 4–42 weeks). All tumors were thin, ranging from in situ to 0.45-mm thick. Wild-type BRAF was detected in the 21 melanomas sampled; 1 lesion showed mutated NRAS.¹³

The exact incidence of SPM in the setting of BRAF inhibition is thought to be at least 10-fold less than SCC and KA.² Patients on BRAF inhibitor therapy should have routine full-body skin examinations, given the increased risk for SPM and SCC.

Another drug belonging to the tyrosine kinase inhibitor family, sorafenib, is used in the treatment of solid tumors, particularly hepatocellular and renal cell carcinomas, and also has been associated with development of cutaneous SCC and KAs.¹⁴ Sorafenib is a multiple tyrosine kinase inhibitor that also inhibits the RAF serine/threonine kinases. Similar to vemurafenib and dabrafenib, SCCs and KAs associated with sorafenib tend to arise in patients with chronic actinic damage during the first 2 months of treatment. It has been hypothesized that inhibition of RAF kinases is pathogenic in inducing SCCs because these lesions have not been reported with sunitinib, another multiple tyrosine kinase inhibitor that lacks the ability to inhibit serine/threonine kinases.^15,16 Although SCCs and KAs associated with sorafenib tend to be low grade, it is reasonable to consider sunitinib or an alternative tyrosine kinase inhibitor in patients who develop multiple SCCs while taking sorafenib.¹⁶

Sonic Hedgehog–Inhibiting Agents

Vismodegib, the first small molecule inhibitor of the signaling protein smoothened, gained FDA approval for the treatment of metastatic or locally advanced basal cell carcinoma (BCC) in 2012. A second agent with an identical mechanism of action, sonidegib, was approved by the FDA for locally advanced BCC in 2015. Approximately 90% of BCCs contain mutations in the sonic hedgehog pathway, which lead to constitutive smoothened activation and uncontrolled cell proliferation.¹⁷ The development of smoothened inhibitors introduced a much-needed treatment for inoperable or metastatic BCC,^17,18 though long-term utility is limited by drug resistance with extended use in this patient population.^19,20 Several case reports have documented the emergence of KA²¹ and cutaneous SCC following vismodegib treatment of advanced or metastatic BCC.^22-24 A larger case-control study by Mohan et al²⁵ showed that patients with BCC treated with vismodegib had an increased risk for non-BCC malignancy (hazard ratio [HR]=6.37), most of which were cutaneous SCC (HR=8.12).

The mechanism by which selective inhibition of smoothened leads to cutaneous SCC is unclear. A study found that patients on vismodegib who developed SCC within the original BCC site had elevated ERK levels within tumor tissue, suggesting that the RAS/RAF/MAPK pathway can become upregulated during hedgehog inhibition.²⁶ Other studies looking at hedgehog inhibition in medulloblastoma models also have shown activated RAS/RAF/MAPK pathways.²⁵ These findings suggest that tumors under smoothened inhibition might be able to bypass the sonic hedgehog pathway and continue to grow by upregulating alternative growth pathways, such as RAS/RAF/MAPK.^25,26

The incidence of cutaneous SCC following vismodegib treatment is unknown. Chang and Oro²⁷ examined BCC tumor regrowth from secondary (acquired) resistance to vismodegib and noted that lesions recurred within 1 cm of the original tumor 21% of the time. Although none of the 12 patients whose tumors regrew during treatment were reported to have developed SCC, several demonstrated different BCC subtypes than the pretreatment specimen. The authors proposed that regrowth of BCC was due to upregulated alternative pathways allowing tumors to bypass smoothened inhibition, which is similar to the proposed mechanism for SCC development in vismodegib patients.²⁷

Prospective studies are needed to confirm the link between vismodegib and cutaneous SCC; establish the incidence of SCC development; and identify any pretreatment factors, tumor characteristics, or treatment details (eg, dosage, duration) that might contribute to SCC development. Furthermore, because Mohan et al²⁵ observed that vismodegib-treated patients were less likely to develop SCC in situ than controls, it is unknown if these tumors are more aggressive than traditional SCC. At this point, careful surveillance and regular full-body skin examinations are advised for patients on vismodegib for treatment of advanced BCC.

JAK Inhibitors

Another class of medications potentially associated with increased development of nonmelanoma skin cancer (NMSC) is the JAK inhibitors (also known as jakinibs). Many proinflammatory signaling pathways converge on the JAK family of enzymes—JAK1, JAK2, JAK3, and TYK2. These enzymes operate in cytokine signal transduction by phosphorylating activated cytokine receptors, which allows for recruitment and activation by means of phosphorylation of transcription factors collectively known as signal transducers and activators of transcription (STATs). Phosphorylated STATs dimerize and translocate to the nucleus, acting as direct transcription promoters. Janus kinase inhibitors modulate the immune response by reducing the effect of interleukin and interferon signaling.

Ruxolitinib, a JAK1/JAK2 inhibitor, was the first JAK inhibitor approved by the FDA and is indicated for the treatment of myelofibrosis and polycythemia vera. Additionally, oral and topical JAK inhibitors have shown efficacy in the treatment of psoriasis, rheumatoid arthritis, alopecia areata, vitiligo, and pruritus from atopic dermatitis.²⁸

The JAK-STAT pathway is complex, and the biological activity of the pathway is both proinflammatory and pro–cell survival and proliferation. Because signaling through the pathway can increase angiogenesis and inhibit apoptosis, inhibition of this pathway has been exploited for the treatment of some tumors. However, inhibition of interferon and proinflammatory interleukin signaling also can potentially promote tumor growth by means of inhibition of downstream cytotoxic T-cell signaling, theoretically increasing the risk for NMSC. A study examining the 5-year efficacy of ruxolitinib in myelofibrosis patients (COMFORT-II trial) found that 17.1% of patients developed NMSC compared to only 2.7% of those on the best available therapy. After adjustment by patient exposure, the NMSC rate was still doubled for ruxolitinib-treated patients compared to controls (6.1/100 patient-years and 3.0/100 patient-years, respectively).²⁹ Eighty-week follow-up of the phase 3 clinical trial of ruxolitinib for the treatment of polycythemia vera also noted an increased incidence of NMSC, albeit a more conservative increase. Patients randomized to the ruxolitinib treatment group developed NMSC at a rate of 4.4/100 patient-years, whereas the rate for controls treated with best available therapy was 2.7/100 patient-years.³⁰ In contrast, 5-year follow-up of the COMFORT-I trial, also examining the efficacy of ruxolitinib in myelofibrosis, showed no increased risk for NMSC between ruxolitinib-treated patients and placebo (2.7/100 patient-years and 3.9/100 patient-years, respectively).³¹

A 2017 case series described 5 patients with myelofibrosis who developed multiple skin cancers with aggressive features while receiving ruxolitinib.³² Duration of ruxolitinib therapy ranged from 4 months to 4 years; 3 patients had a history of hydroxyurea exposure, and only 1 patient had a history of NMSC. High-risk cutaneous SCC, undifferentiated pleomorphic sarcoma, and lentigo maligna melanoma (Breslow thickness, 0.45 mm) were among the tumors reported in this series. Although no definitive conclusion can be made regarding the causality of JAK inhibitors in promoting these tumors, the association warrants further investigation. Clinicians should be aware that ruxolitinib might amplify the risk for NMSC in patients with pre-existing genetic or exposure-related susceptibility. Interruption of drug therapy may be necessary in managing patients who develop an aggressive tumor.³²

In contrast, tofacitinib, which specifically inhibits JAK3, carries very low risk, if any, for NMSC when used for the treatment of psoriasis and rheumatoid arthritis. Results from 2 phase 3 trials analyzing the efficacy of tofacitinib in psoriasis demonstrated that only 2 of 1486 patients treated developed NMSC compared to none in the control group.³³ Furthermore, analysis of NMSC across the tofacitinib rheumatoid arthritis clinical program, which included a total of 15,103 patient-years of exposure, demonstrated that the overall NMSC incidence was 0.55 for every 100 patient-years. Of note, the risk in patients receiving high-dose treatment (10 mg vs 5 mg) was nearly doubled in long-term follow-up studies (0.79/100 patient-years and 0.41/100 patient-years, respectively). Overall, the study concluded that treatment with tofacitinib presents no greater increased risk for NMSC than treatment with tumor necrosis factor inhibitors.³³

PDE-5 Inhibitors

Phosphodiesterase 5 inhibitors, such as sildenafil citrate, have been widely prescribed for the treatment of erectile dysfunction. Studies have shown that BRAF-activated melanomas, which occur in approximately 50% to 70% of melanomas, also result in reduced PDE-5 expression.^34-36 In these melanomas, downregulation of PDE-5 results in increased intracellular calcium,³⁶ which has been shown to induce melanoma invasion.^36,37 Given this similarity in molecular pathway between BRAF-activated melanomas and PDE-5 inhibitors, there has been increased concern that PDE-5 inhibitors might be associated with an increased risk for melanoma.

In 2014, Li et al³⁸ published a retrospective analysis suggesting an association with sildenafil and an increased risk for melanoma. Their study utilized the Health Professionals Follow-up Study to identify a statistically significant elevation in the risk for invasive melanoma with both recent sildenafil use (multivariate-adjusted HR=2.24) and use at any time (HR=1.92). These results controlled for confounding variables, such as presence of major chronic disease, use of other erectile dysfunction treatments, family history of melanoma, history of sun exposure, and UV index of the patient’s residence. Notably, the study also found that sildenafil did not affect the incidence of BCC or SCC.³⁸

In 2015, Loeb et al³⁹ also examined the potential association between PDE-5 inhibitors and melanoma. Review of several Swedish drug and cancer registries allowed for analysis of melanoma risk and PDE-5 inhibitor use, based on number of prescriptions filled and type of PDE-5 inhibitor prescribed. Their analysis showed that men developing melanoma were more likely than nonmelanoma controls to have taken a PDE-5 inhibitor (11% vs 8%). In a subgroup analysis, however, statistical significance was shown for men with only a single prescription filled (34% of cases; P<.05), whereas the difference for men with multiple filled prescriptions did not meet statistical significance. Furthermore, the study did not find increased risk with longer-acting tadalafil and vardenafil (odds ratio [OR]=1.16) compared to sildenafil (OR=1.14). Last, use of PDE-5 inhibitors was only associated with stage 0 (OR=1.49) and stage I (OR=1.21) tumors, not with stages II to IV (OR=0.83) tumors. Although there was a statistically significant association between PDE-5 inhibitors and malignant melanoma (P<.05), the subgroup analysis findings pointed away from a causal relationship and likely toward a confounding of variable(s).³⁹

A 2016 study by Lian et al⁴⁰ looked at the risk for melanoma in a cohort of patients diagnosed with erectile dysfunction. No association between PDE-5 inhibitors and melanoma risk was shown when comparing patients who received a PDE-5 inhibitor and those who did not receive a PDE-5 inhibitor. However, secondary analysis did show that melanoma risk was increased among patients receiving more pills (34%) and prescriptions (30%). The authors concluded that there was no association between PDE-5 inhibitor use and overall increased risk for melanoma, and the increased risk associated with a greater number of pills and prescriptions would require further study.⁴⁰

In contrast, a 2017 meta-analysis by Tang et al⁴¹ of 5 studies (3 of which were the aforementioned trials^38-40) concluded that use of PDE-5 inhibitors was associated with a small but significantly increased risk for melanoma (OR=1.12) and BCC (OR=1.14) but not SCC. Furthermore, the study found no evidence of dosage-dependent association between PDE-5 inhibitor use and melanoma risk.⁴¹

Overall, clinical studies have been inconclusive in determining the risk for melanoma in the setting of PDE-5 inhibitor use. Studies showing an increased rate of melanoma within patient cohorts receiving PDE-5 inhibitors are limited; results might be affected by confounding variables. However, given the similarity in mechanism between PDE-5 inhibitors and HRAS-activated melanomas, it is reasonable to continue research into this potential association.

Conclusion

Since the turn of the century, drugs targeting cell-signaling pathways have been developed to treat inflammatory, oncologic, and immune conditions. The role of immunosuppressants in promoting skin cancer is well established and supported by a vast literature base. However, associations are less clear with newer immunomodulatory and antineoplastic medications. Skin cancer has been reported in association with BRAF inhibitors, sonic hedgehog–inhibiting agents, JAK inhibitors, and PDE-5 inhibitors. In the case of JAK and PDE-5 inhibitors, the increased risk for melanoma and NMSC is somewhat inconclusive; risk is more firmly established for BRAF inhibitors and smoothened inhibitors. For the antineoplastic agents reviewed, the therapeutic effect of cancer regression is well documented, and benefits of continued therapy outweigh the increased risk for skin cancer promotion in nearly all cases. The value of early detection has been well documented for skin malignancy; therefore, increased skin surveillance and prompt management of suspicious lesions should be a priority for physicians treating patients undergoing therapy with these medications

Dermatologists are increasingly called on to evaluate patients with complex medical problems who are often taking many medications. Over the last several decades, many new drugs that target molecular pathways in carcinogenesis and the inflammatory immune system have been developed. Increased skin cancer risk has been reported in association with BRAF inhibitors, sonic hedgehog–inhibiting agents, Janus kinase (JAK) inhibitors, and phosphodiesterase 5 (PDE-5) inhibitors. We review the literature and data regarding the significance and strength of these associations and the molecular pathways by which these medications promote cutaneous tumorigenesis. The association of skin cancer with drugs that either induce photosensitivity—nonsteroidal anti-inflammatory drugs, antibiotics (eg, tetracyclines, fluoroquinolones, trimethoprim-sulfamethoxazole), voriconazole, thiazides—or suppress the immune system—certain biologics (eg, anti–tumor necrosis factor agents), calcineurin inhibitors, thiopurines, methotrexate, cyclosporine—is well known and is therefore not reviewed in this discussion.

BRAF Inhibitors

The mitogen-activated protein kinase (MAPK) pathway (also known as the RAS/RAF/MAPK signaling pathway) is important in growth factor–receptor signaling and plays a key role in cell differentiation, survival, and proliferation. Activating mutations in this pathway allow cells to grow and proliferate in a growth factor–independent manner. Twenty percent of human cancers harbor a mutation in the RAS oncogene, an upstream mediator of the pathway.¹ Activating mutations in BRAF, a serine/threonine kinase, predominate in cutaneous melanoma and also have been found in 40% to 70% of papillary thyroid malignancies, 10% to 20% of cholangiocarcinomas, and 5% to 20% of colorectal carcinomas. The most common BRAF mutation in cutaneous melanoma is V600E, which involves a glutamic acid for valine substitution at codon 600. This mutation activates BRAF 500-fold and is present in approximately 50% of melanomas.^1,2

Vemurafenib, a selective BRAF inhibitor, was approved by the US Food and Drug Administration (FDA) for the treatment of metastatic melanoma in the United States in 2011. Phase 3 trial data demonstrated that vemurafenib resulted in improved survival and decreased risk for disease progression compared to dacarbazine, the former best treatment.³ During phase 1 testing, it became apparent that vemurafenib treatment was associated with a 31% increased risk for squamous cell carcinoma (SCC), most commonly well-differentiated SCC, and keratoacanthomas (KAs).⁴ This association was confirmed in phase 2 and 3 studies, though the incidence was lower. McArthur et al⁵ reported a 19% incidence of cutaneous SCC with extended follow-up analysis of the phase 3 trial. Dabrafenib, another BRAF inhibitor, has been similarly associated with increasing the risk for SCC and KA.

In one study, the mean time to development of SCC after initiating vemurafenib therapy was 10 weeks, with lesions reported as early as 3 weeks. Most patients had clinical signs of chronically sun damaged skin; however, a history of SCC was present in only 17%. Most lesions (63%) were characterized as KAs.⁶

The mechanism for BRAF inhibitor–induced squamoproliferative growth is due to paradoxical activation of the MAPK pathway in cells with wild-type BRAF that harbor upstream-activating mutations in RAS or tyrosine kinase receptors.⁷ In the presence of a BRAF inhibitor, inactivated BRAF forms heterodimers with wild-type CRAF (a BRAF-CRAF heterodimer). The heterodimer forms a complex with the mutant RAS that leads to transactivation of the CRAF molecule,^8,9 resulting in a paradoxical increase in MAPK signaling and consequent ERK phosphorylation and activation through CRAF signaling. RAS, particularly HRAS, mutations have been found in 60% of all vemurafenib-associated SCCs and KAs. For this reason, it is thought that vemurafenib potentiates tumorigenesis in subclinical lesions harboring upstream MAPK pathway mutations as opposed to inducing de novo lesions.⁶

Because BRAF inhibitors are remarkably efficacious in the treatment of metastatic melanomas harboring the V600E BRAF mutation, there are no restrictions on their use, despite the known increased risk for SCC. Squamous cell carcinomas tend to be low grade, and all tumors that developed in phase 1 to 3 trials were treated with simple excision. The development of SCC did not necessitate interruption of treatment. Furthermore, the addition of MEK inhibition to BRAF inhibitor therapy reduces the risk for SCC from 19% to 7%.^7,10,11

In addition to SCC, second primary melanomas (SPMs) have been reported in patients treated with BRAF inhibitors. It has been shown that these melanomas occur in melanocytes with wild-type BRAF. It has been postulated that some of these tumors occur in cells that harbor upstream mutations in RAS, whereas others might result from alternate signaling through non-RAF oncogenic pathways.^9,12

Zimmer et al¹ reported 12 SPMs in 11 patients treated with BRAF inhibitor therapy. They reported a median delay of 8 weeks (range, 4–27 weeks) for SPM development. Tumors were detected in early stages; 1 tumor harbored an NRAS mutation.¹

Dalle et al¹³ reported 25 SPMs in 120 vemurafenib-treated patients. Median delay in SPM development was 14 weeks (range, 4–42 weeks). All tumors were thin, ranging from in situ to 0.45-mm thick. Wild-type BRAF was detected in the 21 melanomas sampled; 1 lesion showed mutated NRAS.¹³

The exact incidence of SPM in the setting of BRAF inhibition is thought to be at least 10-fold less than SCC and KA.² Patients on BRAF inhibitor therapy should have routine full-body skin examinations, given the increased risk for SPM and SCC.

Another drug belonging to the tyrosine kinase inhibitor family, sorafenib, is used in the treatment of solid tumors, particularly hepatocellular and renal cell carcinomas, and also has been associated with development of cutaneous SCC and KAs.¹⁴ Sorafenib is a multiple tyrosine kinase inhibitor that also inhibits the RAF serine/threonine kinases. Similar to vemurafenib and dabrafenib, SCCs and KAs associated with sorafenib tend to arise in patients with chronic actinic damage during the first 2 months of treatment. It has been hypothesized that inhibition of RAF kinases is pathogenic in inducing SCCs because these lesions have not been reported with sunitinib, another multiple tyrosine kinase inhibitor that lacks the ability to inhibit serine/threonine kinases.^15,16 Although SCCs and KAs associated with sorafenib tend to be low grade, it is reasonable to consider sunitinib or an alternative tyrosine kinase inhibitor in patients who develop multiple SCCs while taking sorafenib.¹⁶

Sonic Hedgehog–Inhibiting Agents

Vismodegib, the first small molecule inhibitor of the signaling protein smoothened, gained FDA approval for the treatment of metastatic or locally advanced basal cell carcinoma (BCC) in 2012. A second agent with an identical mechanism of action, sonidegib, was approved by the FDA for locally advanced BCC in 2015. Approximately 90% of BCCs contain mutations in the sonic hedgehog pathway, which lead to constitutive smoothened activation and uncontrolled cell proliferation.¹⁷ The development of smoothened inhibitors introduced a much-needed treatment for inoperable or metastatic BCC,^17,18 though long-term utility is limited by drug resistance with extended use in this patient population.^19,20 Several case reports have documented the emergence of KA²¹ and cutaneous SCC following vismodegib treatment of advanced or metastatic BCC.^22-24 A larger case-control study by Mohan et al²⁵ showed that patients with BCC treated with vismodegib had an increased risk for non-BCC malignancy (hazard ratio [HR]=6.37), most of which were cutaneous SCC (HR=8.12).

The mechanism by which selective inhibition of smoothened leads to cutaneous SCC is unclear. A study found that patients on vismodegib who developed SCC within the original BCC site had elevated ERK levels within tumor tissue, suggesting that the RAS/RAF/MAPK pathway can become upregulated during hedgehog inhibition.²⁶ Other studies looking at hedgehog inhibition in medulloblastoma models also have shown activated RAS/RAF/MAPK pathways.²⁵ These findings suggest that tumors under smoothened inhibition might be able to bypass the sonic hedgehog pathway and continue to grow by upregulating alternative growth pathways, such as RAS/RAF/MAPK.^25,26

The incidence of cutaneous SCC following vismodegib treatment is unknown. Chang and Oro²⁷ examined BCC tumor regrowth from secondary (acquired) resistance to vismodegib and noted that lesions recurred within 1 cm of the original tumor 21% of the time. Although none of the 12 patients whose tumors regrew during treatment were reported to have developed SCC, several demonstrated different BCC subtypes than the pretreatment specimen. The authors proposed that regrowth of BCC was due to upregulated alternative pathways allowing tumors to bypass smoothened inhibition, which is similar to the proposed mechanism for SCC development in vismodegib patients.²⁷

Prospective studies are needed to confirm the link between vismodegib and cutaneous SCC; establish the incidence of SCC development; and identify any pretreatment factors, tumor characteristics, or treatment details (eg, dosage, duration) that might contribute to SCC development. Furthermore, because Mohan et al²⁵ observed that vismodegib-treated patients were less likely to develop SCC in situ than controls, it is unknown if these tumors are more aggressive than traditional SCC. At this point, careful surveillance and regular full-body skin examinations are advised for patients on vismodegib for treatment of advanced BCC.

JAK Inhibitors

Another class of medications potentially associated with increased development of nonmelanoma skin cancer (NMSC) is the JAK inhibitors (also known as jakinibs). Many proinflammatory signaling pathways converge on the JAK family of enzymes—JAK1, JAK2, JAK3, and TYK2. These enzymes operate in cytokine signal transduction by phosphorylating activated cytokine receptors, which allows for recruitment and activation by means of phosphorylation of transcription factors collectively known as signal transducers and activators of transcription (STATs). Phosphorylated STATs dimerize and translocate to the nucleus, acting as direct transcription promoters. Janus kinase inhibitors modulate the immune response by reducing the effect of interleukin and interferon signaling.

Ruxolitinib, a JAK1/JAK2 inhibitor, was the first JAK inhibitor approved by the FDA and is indicated for the treatment of myelofibrosis and polycythemia vera. Additionally, oral and topical JAK inhibitors have shown efficacy in the treatment of psoriasis, rheumatoid arthritis, alopecia areata, vitiligo, and pruritus from atopic dermatitis.²⁸

The JAK-STAT pathway is complex, and the biological activity of the pathway is both proinflammatory and pro–cell survival and proliferation. Because signaling through the pathway can increase angiogenesis and inhibit apoptosis, inhibition of this pathway has been exploited for the treatment of some tumors. However, inhibition of interferon and proinflammatory interleukin signaling also can potentially promote tumor growth by means of inhibition of downstream cytotoxic T-cell signaling, theoretically increasing the risk for NMSC. A study examining the 5-year efficacy of ruxolitinib in myelofibrosis patients (COMFORT-II trial) found that 17.1% of patients developed NMSC compared to only 2.7% of those on the best available therapy. After adjustment by patient exposure, the NMSC rate was still doubled for ruxolitinib-treated patients compared to controls (6.1/100 patient-years and 3.0/100 patient-years, respectively).²⁹ Eighty-week follow-up of the phase 3 clinical trial of ruxolitinib for the treatment of polycythemia vera also noted an increased incidence of NMSC, albeit a more conservative increase. Patients randomized to the ruxolitinib treatment group developed NMSC at a rate of 4.4/100 patient-years, whereas the rate for controls treated with best available therapy was 2.7/100 patient-years.³⁰ In contrast, 5-year follow-up of the COMFORT-I trial, also examining the efficacy of ruxolitinib in myelofibrosis, showed no increased risk for NMSC between ruxolitinib-treated patients and placebo (2.7/100 patient-years and 3.9/100 patient-years, respectively).³¹

A 2017 case series described 5 patients with myelofibrosis who developed multiple skin cancers with aggressive features while receiving ruxolitinib.³² Duration of ruxolitinib therapy ranged from 4 months to 4 years; 3 patients had a history of hydroxyurea exposure, and only 1 patient had a history of NMSC. High-risk cutaneous SCC, undifferentiated pleomorphic sarcoma, and lentigo maligna melanoma (Breslow thickness, 0.45 mm) were among the tumors reported in this series. Although no definitive conclusion can be made regarding the causality of JAK inhibitors in promoting these tumors, the association warrants further investigation. Clinicians should be aware that ruxolitinib might amplify the risk for NMSC in patients with pre-existing genetic or exposure-related susceptibility. Interruption of drug therapy may be necessary in managing patients who develop an aggressive tumor.³²

In contrast, tofacitinib, which specifically inhibits JAK3, carries very low risk, if any, for NMSC when used for the treatment of psoriasis and rheumatoid arthritis. Results from 2 phase 3 trials analyzing the efficacy of tofacitinib in psoriasis demonstrated that only 2 of 1486 patients treated developed NMSC compared to none in the control group.³³ Furthermore, analysis of NMSC across the tofacitinib rheumatoid arthritis clinical program, which included a total of 15,103 patient-years of exposure, demonstrated that the overall NMSC incidence was 0.55 for every 100 patient-years. Of note, the risk in patients receiving high-dose treatment (10 mg vs 5 mg) was nearly doubled in long-term follow-up studies (0.79/100 patient-years and 0.41/100 patient-years, respectively). Overall, the study concluded that treatment with tofacitinib presents no greater increased risk for NMSC than treatment with tumor necrosis factor inhibitors.³³

PDE-5 Inhibitors

Phosphodiesterase 5 inhibitors, such as sildenafil citrate, have been widely prescribed for the treatment of erectile dysfunction. Studies have shown that BRAF-activated melanomas, which occur in approximately 50% to 70% of melanomas, also result in reduced PDE-5 expression.^34-36 In these melanomas, downregulation of PDE-5 results in increased intracellular calcium,³⁶ which has been shown to induce melanoma invasion.^36,37 Given this similarity in molecular pathway between BRAF-activated melanomas and PDE-5 inhibitors, there has been increased concern that PDE-5 inhibitors might be associated with an increased risk for melanoma.

In 2014, Li et al³⁸ published a retrospective analysis suggesting an association with sildenafil and an increased risk for melanoma. Their study utilized the Health Professionals Follow-up Study to identify a statistically significant elevation in the risk for invasive melanoma with both recent sildenafil use (multivariate-adjusted HR=2.24) and use at any time (HR=1.92). These results controlled for confounding variables, such as presence of major chronic disease, use of other erectile dysfunction treatments, family history of melanoma, history of sun exposure, and UV index of the patient’s residence. Notably, the study also found that sildenafil did not affect the incidence of BCC or SCC.³⁸

In 2015, Loeb et al³⁹ also examined the potential association between PDE-5 inhibitors and melanoma. Review of several Swedish drug and cancer registries allowed for analysis of melanoma risk and PDE-5 inhibitor use, based on number of prescriptions filled and type of PDE-5 inhibitor prescribed. Their analysis showed that men developing melanoma were more likely than nonmelanoma controls to have taken a PDE-5 inhibitor (11% vs 8%). In a subgroup analysis, however, statistical significance was shown for men with only a single prescription filled (34% of cases; P<.05), whereas the difference for men with multiple filled prescriptions did not meet statistical significance. Furthermore, the study did not find increased risk with longer-acting tadalafil and vardenafil (odds ratio [OR]=1.16) compared to sildenafil (OR=1.14). Last, use of PDE-5 inhibitors was only associated with stage 0 (OR=1.49) and stage I (OR=1.21) tumors, not with stages II to IV (OR=0.83) tumors. Although there was a statistically significant association between PDE-5 inhibitors and malignant melanoma (P<.05), the subgroup analysis findings pointed away from a causal relationship and likely toward a confounding of variable(s).³⁹

A 2016 study by Lian et al⁴⁰ looked at the risk for melanoma in a cohort of patients diagnosed with erectile dysfunction. No association between PDE-5 inhibitors and melanoma risk was shown when comparing patients who received a PDE-5 inhibitor and those who did not receive a PDE-5 inhibitor. However, secondary analysis did show that melanoma risk was increased among patients receiving more pills (34%) and prescriptions (30%). The authors concluded that there was no association between PDE-5 inhibitor use and overall increased risk for melanoma, and the increased risk associated with a greater number of pills and prescriptions would require further study.⁴⁰

In contrast, a 2017 meta-analysis by Tang et al⁴¹ of 5 studies (3 of which were the aforementioned trials^38-40) concluded that use of PDE-5 inhibitors was associated with a small but significantly increased risk for melanoma (OR=1.12) and BCC (OR=1.14) but not SCC. Furthermore, the study found no evidence of dosage-dependent association between PDE-5 inhibitor use and melanoma risk.⁴¹

Overall, clinical studies have been inconclusive in determining the risk for melanoma in the setting of PDE-5 inhibitor use. Studies showing an increased rate of melanoma within patient cohorts receiving PDE-5 inhibitors are limited; results might be affected by confounding variables. However, given the similarity in mechanism between PDE-5 inhibitors and HRAS-activated melanomas, it is reasonable to continue research into this potential association.

Conclusion

Since the turn of the century, drugs targeting cell-signaling pathways have been developed to treat inflammatory, oncologic, and immune conditions. The role of immunosuppressants in promoting skin cancer is well established and supported by a vast literature base. However, associations are less clear with newer immunomodulatory and antineoplastic medications. Skin cancer has been reported in association with BRAF inhibitors, sonic hedgehog–inhibiting agents, JAK inhibitors, and PDE-5 inhibitors. In the case of JAK and PDE-5 inhibitors, the increased risk for melanoma and NMSC is somewhat inconclusive; risk is more firmly established for BRAF inhibitors and smoothened inhibitors. For the antineoplastic agents reviewed, the therapeutic effect of cancer regression is well documented, and benefits of continued therapy outweigh the increased risk for skin cancer promotion in nearly all cases. The value of early detection has been well documented for skin malignancy; therefore, increased skin surveillance and prompt management of suspicious lesions should be a priority for physicians treating patients undergoing therapy with these medications

The Diagnosis: Inflammatory Urothelial Carcinoma 

Microscopic examination revealed metastatic carcinoma with extensive dermal lymphatic invasion (Figure). Immunohistochemical stains were positive for p63 and GATA3, markers for urothelial carcinomas, and negative for S-100 and Melan-A, markers for melanoma. Thus, the biopsy was compatible with a diagnosis of urothelial carcinoma. Gram and Grocott-Gomori methenamine-silver stains were negative for bacterial or fungal organisms. An additional 4-mm punch biopsy was performed of the left thigh at the distal-most aspect of the eruption to determine the extent of cutaneous metastasis. Pathology again showed metastatic urothelial carcinoma with extensive dermal lymphatic involvement and overlying epidermal spongiosis.

The patient had a history of bladder cancer diagnosed 1.5 years prior to presentation. It was a high-grade (World Health Organization) urothelial carcinoma that penetrated the bladder muscular wall, focally infiltrating into pericystic fat with multifocal seeding of pericystic lymphatics. It was unresponsive to bacillus Calmette-Guérin therapy. He underwent a cystoprostatectomy and bilateral staging lymph node dissection with clear surgical margins without adjuvant chemotherapy or radiation. He also reported a history of 2 prior cutaneous melanomas that were excised without sentinel lymph node biopsy. 

Four months prior to presentation, he developed a mildly pruritic cutaneous eruption on the abdomen that was treated with topical miconazole for presumed tinea cruris without improvement. He also was previously diagnosed with candidiasis of his urostomy and was taking oral fluconazole. The patient was admitted for the abdominal pain and distension, and computed tomography of the abdomen and pelvis revealed peritoneal carcinomatosis resulting in mechanical small bowel obstruction as well as enlarged pelvic and retroperitoneal lymph nodes. Confirmation of metastatic disease via skin biopsy avoided an invasive peritoneal biopsy. He was treated with triamcinolone acetonide ointment 0.1% with moderate relief of pruritus, and a palliative percutaneous endoscopic gastrostomy tube was placed for bowel decompression. The patient's hospital course was complicated by Proteus mirabilis bacteremia requiring cefepime. He was transitioned to home hospice and died 1 month after presentation. 

Inflammatory carcinoma, also called carcinoma erysipeloides, is a type of cutaneous metastasis most commonly seen in breast adenocarcinoma. Reported cases secondary to urothelial carcinoma are rare and most often involve the abdomen, groin, and lower extremities.^1-5 Clinically, inflammatory carcinoma presents as erythematous indurated patches or plaques with well-defined borders, often with edema, warmth, and tenderness. Its morphologic appearance is due to the obstruction of lymphatic vessels by tumor cells and the release of inflammatory cytokines. Its presentation can mimic other dermatoses such as cellulitis, erysipelas, fungal infection, radiation dermatitis, Majocchi granuloma, or contact dermatitis.⁶ Cutaneous metastases may be the first clinical manifestations of metastatic disease, and they may occur due to hematogenous and lymphatic spread, direct contiguous tissue invasion, or iatrogenic implantation following surgical excision of the primary tumor. Histologically, nuclear markers GATA3 and p63 stain positively in urothelial carcinomas and are negative in prostatic adenocarcinomas.^7,8 Other markers may be used such as cytokeratins 7 and 20, which are cytoplasmic epithelial markers that both stain positive in urothelial neoplasms.⁹  

Inflammatory carcinoma may be treated with radiation or systemic chemotherapy depending on the extent of systemic involvement in the patient; however, its presence portends a poor prognosis. Less than 1% of genitourinary malignancies have cutaneous involvement, and median disease-specific survival is less than 6 months from presentation of the cutaneous metastasis.¹⁰ Clinicians faced with a recalcitrant inflammatory cutaneous eruption should maintain a high index of suspicion for cutaneous metastases, particularly in patients with a history of cancer. Early dermatology referral may help establish the diagnosis and guide disease-targeted therapy or goals of care discussions. 

The Diagnosis: Inflammatory Urothelial Carcinoma 

Microscopic examination revealed metastatic carcinoma with extensive dermal lymphatic invasion (Figure). Immunohistochemical stains were positive for p63 and GATA3, markers for urothelial carcinomas, and negative for S-100 and Melan-A, markers for melanoma. Thus, the biopsy was compatible with a diagnosis of urothelial carcinoma. Gram and Grocott-Gomori methenamine-silver stains were negative for bacterial or fungal organisms. An additional 4-mm punch biopsy was performed of the left thigh at the distal-most aspect of the eruption to determine the extent of cutaneous metastasis. Pathology again showed metastatic urothelial carcinoma with extensive dermal lymphatic involvement and overlying epidermal spongiosis.

The patient had a history of bladder cancer diagnosed 1.5 years prior to presentation. It was a high-grade (World Health Organization) urothelial carcinoma that penetrated the bladder muscular wall, focally infiltrating into pericystic fat with multifocal seeding of pericystic lymphatics. It was unresponsive to bacillus Calmette-Guérin therapy. He underwent a cystoprostatectomy and bilateral staging lymph node dissection with clear surgical margins without adjuvant chemotherapy or radiation. He also reported a history of 2 prior cutaneous melanomas that were excised without sentinel lymph node biopsy. 

Four months prior to presentation, he developed a mildly pruritic cutaneous eruption on the abdomen that was treated with topical miconazole for presumed tinea cruris without improvement. He also was previously diagnosed with candidiasis of his urostomy and was taking oral fluconazole. The patient was admitted for the abdominal pain and distension, and computed tomography of the abdomen and pelvis revealed peritoneal carcinomatosis resulting in mechanical small bowel obstruction as well as enlarged pelvic and retroperitoneal lymph nodes. Confirmation of metastatic disease via skin biopsy avoided an invasive peritoneal biopsy. He was treated with triamcinolone acetonide ointment 0.1% with moderate relief of pruritus, and a palliative percutaneous endoscopic gastrostomy tube was placed for bowel decompression. The patient's hospital course was complicated by Proteus mirabilis bacteremia requiring cefepime. He was transitioned to home hospice and died 1 month after presentation. 

Inflammatory carcinoma, also called carcinoma erysipeloides, is a type of cutaneous metastasis most commonly seen in breast adenocarcinoma. Reported cases secondary to urothelial carcinoma are rare and most often involve the abdomen, groin, and lower extremities.^1-5 Clinically, inflammatory carcinoma presents as erythematous indurated patches or plaques with well-defined borders, often with edema, warmth, and tenderness. Its morphologic appearance is due to the obstruction of lymphatic vessels by tumor cells and the release of inflammatory cytokines. Its presentation can mimic other dermatoses such as cellulitis, erysipelas, fungal infection, radiation dermatitis, Majocchi granuloma, or contact dermatitis.⁶ Cutaneous metastases may be the first clinical manifestations of metastatic disease, and they may occur due to hematogenous and lymphatic spread, direct contiguous tissue invasion, or iatrogenic implantation following surgical excision of the primary tumor. Histologically, nuclear markers GATA3 and p63 stain positively in urothelial carcinomas and are negative in prostatic adenocarcinomas.^7,8 Other markers may be used such as cytokeratins 7 and 20, which are cytoplasmic epithelial markers that both stain positive in urothelial neoplasms.⁹  

Inflammatory carcinoma may be treated with radiation or systemic chemotherapy depending on the extent of systemic involvement in the patient; however, its presence portends a poor prognosis. Less than 1% of genitourinary malignancies have cutaneous involvement, and median disease-specific survival is less than 6 months from presentation of the cutaneous metastasis.¹⁰ Clinicians faced with a recalcitrant inflammatory cutaneous eruption should maintain a high index of suspicion for cutaneous metastases, particularly in patients with a history of cancer. Early dermatology referral may help establish the diagnosis and guide disease-targeted therapy or goals of care discussions. 

The Diagnosis: Inflammatory Urothelial Carcinoma 

Microscopic examination revealed metastatic carcinoma with extensive dermal lymphatic invasion (Figure). Immunohistochemical stains were positive for p63 and GATA3, markers for urothelial carcinomas, and negative for S-100 and Melan-A, markers for melanoma. Thus, the biopsy was compatible with a diagnosis of urothelial carcinoma. Gram and Grocott-Gomori methenamine-silver stains were negative for bacterial or fungal organisms. An additional 4-mm punch biopsy was performed of the left thigh at the distal-most aspect of the eruption to determine the extent of cutaneous metastasis. Pathology again showed metastatic urothelial carcinoma with extensive dermal lymphatic involvement and overlying epidermal spongiosis.

The patient had a history of bladder cancer diagnosed 1.5 years prior to presentation. It was a high-grade (World Health Organization) urothelial carcinoma that penetrated the bladder muscular wall, focally infiltrating into pericystic fat with multifocal seeding of pericystic lymphatics. It was unresponsive to bacillus Calmette-Guérin therapy. He underwent a cystoprostatectomy and bilateral staging lymph node dissection with clear surgical margins without adjuvant chemotherapy or radiation. He also reported a history of 2 prior cutaneous melanomas that were excised without sentinel lymph node biopsy. 

Four months prior to presentation, he developed a mildly pruritic cutaneous eruption on the abdomen that was treated with topical miconazole for presumed tinea cruris without improvement. He also was previously diagnosed with candidiasis of his urostomy and was taking oral fluconazole. The patient was admitted for the abdominal pain and distension, and computed tomography of the abdomen and pelvis revealed peritoneal carcinomatosis resulting in mechanical small bowel obstruction as well as enlarged pelvic and retroperitoneal lymph nodes. Confirmation of metastatic disease via skin biopsy avoided an invasive peritoneal biopsy. He was treated with triamcinolone acetonide ointment 0.1% with moderate relief of pruritus, and a palliative percutaneous endoscopic gastrostomy tube was placed for bowel decompression. The patient's hospital course was complicated by Proteus mirabilis bacteremia requiring cefepime. He was transitioned to home hospice and died 1 month after presentation. 

Inflammatory carcinoma, also called carcinoma erysipeloides, is a type of cutaneous metastasis most commonly seen in breast adenocarcinoma. Reported cases secondary to urothelial carcinoma are rare and most often involve the abdomen, groin, and lower extremities.^1-5 Clinically, inflammatory carcinoma presents as erythematous indurated patches or plaques with well-defined borders, often with edema, warmth, and tenderness. Its morphologic appearance is due to the obstruction of lymphatic vessels by tumor cells and the release of inflammatory cytokines. Its presentation can mimic other dermatoses such as cellulitis, erysipelas, fungal infection, radiation dermatitis, Majocchi granuloma, or contact dermatitis.⁶ Cutaneous metastases may be the first clinical manifestations of metastatic disease, and they may occur due to hematogenous and lymphatic spread, direct contiguous tissue invasion, or iatrogenic implantation following surgical excision of the primary tumor. Histologically, nuclear markers GATA3 and p63 stain positively in urothelial carcinomas and are negative in prostatic adenocarcinomas.^7,8 Other markers may be used such as cytokeratins 7 and 20, which are cytoplasmic epithelial markers that both stain positive in urothelial neoplasms.⁹  

Inflammatory carcinoma may be treated with radiation or systemic chemotherapy depending on the extent of systemic involvement in the patient; however, its presence portends a poor prognosis. Less than 1% of genitourinary malignancies have cutaneous involvement, and median disease-specific survival is less than 6 months from presentation of the cutaneous metastasis.¹⁰ Clinicians faced with a recalcitrant inflammatory cutaneous eruption should maintain a high index of suspicion for cutaneous metastases, particularly in patients with a history of cancer. Early dermatology referral may help establish the diagnosis and guide disease-targeted therapy or goals of care discussions. 

To the Editor:

Nevus sebaceous of Jadassohn (or nevus sebaceous [NS]) is a congenital hamartomatous disorder initially described by Jadassohn¹ in 1895. Nevus sebaceous occurs in 0.3% of newborns² and is most commonly identified on the face and scalp.^3,4 Mehregan and Pinkus⁵ characterized NS as an organoid tumor containing multiple skin components with 3 life stages. The first stage—occurring during infancy—consists of immature hair follicles and sebaceous glands. The second stage—beginning at puberty—shows development of sebaceous glands, epidermal hyperplasia, and maturation of apocrine glands. The final stage involves formation of secondary benign and malignant neoplasms.

Historically, basal cell carcinoma (BCC) was thought to be the most common neoplasm arising in NS.^5-8 In 1993, Ackerman et al⁹ introduced a new definition of trichoblastoma (TB), expanding the definition to encompass previously excluded benign follicular neoplasms. Large studies conducted after this new definition was proposed suggested that syringocystadenoma papilliferum and TB develop more frequently than does BCC.^3,4,10-15 Furthermore, Cribier et al⁴ and Merrot et al¹⁵ reviewed prior cases of NS using the new definition and asserted that the majority of previously diagnosed cases of BCC were considered to be TB under the new criteria. With the advent of modern diagnostic testing, the rate of secondary benign neoplasm growth is now thought to be between 7% and 19%, with syringocystadenoma papilliferum arising in 2% to 13% of cases and TB in 1.5% to 7%.^3,4,10-14 Malignant neoplasms are observed much less frequently, with BCC arising in 0% to 1% of NS cases.

Nevus sebaceous lesions typically enlarge during puberty, while malignant neoplasms occur almost exclusively in adulthood,^4,10-12 suggesting that hormones contribute to NS stage progression. We present the case of a woman who developed BCC in a previously asymptomatic NS during pregnancy.

A 32-year-old woman who was otherwise healthy presented to our dermatology clinic with a pink-yellow verrucous plaque on the right temporal hairline extending to the preauricular area of the face. The patient had no personal or family history of skin cancer and no history of tanning bed use. She reported that the lesion had been present since birth. A diagnosis of NS was made.

Two years later, she presented with a new bleeding growth atop the previously diagnosed NS that had been present for approximately 4 months (Figure). At this visit she was pregnant (30 weeks’ gestation). Physical examination revealed a 4-mm, brown, pearly papule at the inferior margin of the previously noted pink verrucous plaque on the right temporal hairline. A biopsy was performed and histopathology displayed aggregates of basaloid cells with a high nuclear to cytoplasmic ratio, peripheral palisading, and abundant melanin, consistent with pigmented BCC. The patient was referred for Mohs micrographic surgery; the lesion was removed with clear margins. The patient had no recurrence of BCC at 36-month follow-up.

Similarly, cases of rapid growth of NS lesions during pregnancy, a state of increased testosterone production,²⁷ have been reported.²⁸ We present a case of a BCC arising in a previously asymptomatic NS during pregnancy. To our knowledge, no large studies have assessed the effect of hormone level changes during pregnancy on NS growth and secondary malignant transformation. Prior to the 1990s, prophylactic excision of NS during childhood was recommended to prevent malignant neoplasm formation.^29,30 More recently, a more conservative approach has been advocated because of a lower rate of malignant transformation than previously thought; some dermatologists recommend close monitoring as an alternative to early removal.^{4,13,14,29,31} This case report proposes that pregnancy may be a time of increased risk for malignant transformation and that NS lesions might require close monitoring during pregnancy.

To the Editor:

Nevus sebaceous of Jadassohn (or nevus sebaceous [NS]) is a congenital hamartomatous disorder initially described by Jadassohn¹ in 1895. Nevus sebaceous occurs in 0.3% of newborns² and is most commonly identified on the face and scalp.^3,4 Mehregan and Pinkus⁵ characterized NS as an organoid tumor containing multiple skin components with 3 life stages. The first stage—occurring during infancy—consists of immature hair follicles and sebaceous glands. The second stage—beginning at puberty—shows development of sebaceous glands, epidermal hyperplasia, and maturation of apocrine glands. The final stage involves formation of secondary benign and malignant neoplasms.

Historically, basal cell carcinoma (BCC) was thought to be the most common neoplasm arising in NS.^5-8 In 1993, Ackerman et al⁹ introduced a new definition of trichoblastoma (TB), expanding the definition to encompass previously excluded benign follicular neoplasms. Large studies conducted after this new definition was proposed suggested that syringocystadenoma papilliferum and TB develop more frequently than does BCC.^3,4,10-15 Furthermore, Cribier et al⁴ and Merrot et al¹⁵ reviewed prior cases of NS using the new definition and asserted that the majority of previously diagnosed cases of BCC were considered to be TB under the new criteria. With the advent of modern diagnostic testing, the rate of secondary benign neoplasm growth is now thought to be between 7% and 19%, with syringocystadenoma papilliferum arising in 2% to 13% of cases and TB in 1.5% to 7%.^3,4,10-14 Malignant neoplasms are observed much less frequently, with BCC arising in 0% to 1% of NS cases.

Nevus sebaceous lesions typically enlarge during puberty, while malignant neoplasms occur almost exclusively in adulthood,^4,10-12 suggesting that hormones contribute to NS stage progression. We present the case of a woman who developed BCC in a previously asymptomatic NS during pregnancy.

A 32-year-old woman who was otherwise healthy presented to our dermatology clinic with a pink-yellow verrucous plaque on the right temporal hairline extending to the preauricular area of the face. The patient had no personal or family history of skin cancer and no history of tanning bed use. She reported that the lesion had been present since birth. A diagnosis of NS was made.

Two years later, she presented with a new bleeding growth atop the previously diagnosed NS that had been present for approximately 4 months (Figure). At this visit she was pregnant (30 weeks’ gestation). Physical examination revealed a 4-mm, brown, pearly papule at the inferior margin of the previously noted pink verrucous plaque on the right temporal hairline. A biopsy was performed and histopathology displayed aggregates of basaloid cells with a high nuclear to cytoplasmic ratio, peripheral palisading, and abundant melanin, consistent with pigmented BCC. The patient was referred for Mohs micrographic surgery; the lesion was removed with clear margins. The patient had no recurrence of BCC at 36-month follow-up.

Similarly, cases of rapid growth of NS lesions during pregnancy, a state of increased testosterone production,²⁷ have been reported.²⁸ We present a case of a BCC arising in a previously asymptomatic NS during pregnancy. To our knowledge, no large studies have assessed the effect of hormone level changes during pregnancy on NS growth and secondary malignant transformation. Prior to the 1990s, prophylactic excision of NS during childhood was recommended to prevent malignant neoplasm formation.^29,30 More recently, a more conservative approach has been advocated because of a lower rate of malignant transformation than previously thought; some dermatologists recommend close monitoring as an alternative to early removal.^{4,13,14,29,31} This case report proposes that pregnancy may be a time of increased risk for malignant transformation and that NS lesions might require close monitoring during pregnancy.

To the Editor:

Nevus sebaceous of Jadassohn (or nevus sebaceous [NS]) is a congenital hamartomatous disorder initially described by Jadassohn¹ in 1895. Nevus sebaceous occurs in 0.3% of newborns² and is most commonly identified on the face and scalp.^3,4 Mehregan and Pinkus⁵ characterized NS as an organoid tumor containing multiple skin components with 3 life stages. The first stage—occurring during infancy—consists of immature hair follicles and sebaceous glands. The second stage—beginning at puberty—shows development of sebaceous glands, epidermal hyperplasia, and maturation of apocrine glands. The final stage involves formation of secondary benign and malignant neoplasms.

Historically, basal cell carcinoma (BCC) was thought to be the most common neoplasm arising in NS.^5-8 In 1993, Ackerman et al⁹ introduced a new definition of trichoblastoma (TB), expanding the definition to encompass previously excluded benign follicular neoplasms. Large studies conducted after this new definition was proposed suggested that syringocystadenoma papilliferum and TB develop more frequently than does BCC.^3,4,10-15 Furthermore, Cribier et al⁴ and Merrot et al¹⁵ reviewed prior cases of NS using the new definition and asserted that the majority of previously diagnosed cases of BCC were considered to be TB under the new criteria. With the advent of modern diagnostic testing, the rate of secondary benign neoplasm growth is now thought to be between 7% and 19%, with syringocystadenoma papilliferum arising in 2% to 13% of cases and TB in 1.5% to 7%.^3,4,10-14 Malignant neoplasms are observed much less frequently, with BCC arising in 0% to 1% of NS cases.

Nevus sebaceous lesions typically enlarge during puberty, while malignant neoplasms occur almost exclusively in adulthood,^4,10-12 suggesting that hormones contribute to NS stage progression. We present the case of a woman who developed BCC in a previously asymptomatic NS during pregnancy.

A 32-year-old woman who was otherwise healthy presented to our dermatology clinic with a pink-yellow verrucous plaque on the right temporal hairline extending to the preauricular area of the face. The patient had no personal or family history of skin cancer and no history of tanning bed use. She reported that the lesion had been present since birth. A diagnosis of NS was made.

Two years later, she presented with a new bleeding growth atop the previously diagnosed NS that had been present for approximately 4 months (Figure). At this visit she was pregnant (30 weeks’ gestation). Physical examination revealed a 4-mm, brown, pearly papule at the inferior margin of the previously noted pink verrucous plaque on the right temporal hairline. A biopsy was performed and histopathology displayed aggregates of basaloid cells with a high nuclear to cytoplasmic ratio, peripheral palisading, and abundant melanin, consistent with pigmented BCC. The patient was referred for Mohs micrographic surgery; the lesion was removed with clear margins. The patient had no recurrence of BCC at 36-month follow-up.

Similarly, cases of rapid growth of NS lesions during pregnancy, a state of increased testosterone production,²⁷ have been reported.²⁸ We present a case of a BCC arising in a previously asymptomatic NS during pregnancy. To our knowledge, no large studies have assessed the effect of hormone level changes during pregnancy on NS growth and secondary malignant transformation. Prior to the 1990s, prophylactic excision of NS during childhood was recommended to prevent malignant neoplasm formation.^29,30 More recently, a more conservative approach has been advocated because of a lower rate of malignant transformation than previously thought; some dermatologists recommend close monitoring as an alternative to early removal.^{4,13,14,29,31} This case report proposes that pregnancy may be a time of increased risk for malignant transformation and that NS lesions might require close monitoring during pregnancy.

To the Editor:

Keratoacanthoma (KA)–type squamous cell carcinomas (SCCs) are rapidly evolving neoplasms of the epithelium that often spontaneously regress but rarely metastasize.^1,2 Keratoacanthomas are thought to ascend from the hair follicle,¹ and they clinically present as an enlarging solitary crateriform nodule with a keratin-filled center. Multiple KAs are rare²; histologically, KAs can be difficult to distinguish from conventional SCCs and are frequently treated by standard surgical excision.¹ Reactive KAs are a subtype of KA that are induced by trauma including UV exposure, electromagnetic radiation, surgical procedures, chemical peels, laser treatments, and rarely tattoos.^3-5

A 56-year-old man presented to the clinic with 3 asymptomatic enlarging papulonodules within a multicolored tattoo along the right forearm and elbow of 5 months’ duration (Figure 1). The lesions developed 1 month after the tattoo was placed and were localized to the areas of red pigment. The patient had several other tattoos. Histologic examination of the lesions revealed a well-differentiated squamous neoplasm with a crateriform invagination consistent with the superficial portion of a KA (Figures 2A–C). The specimen also revealed exogenous red pigment that was consistent with the background tattoo (Figure 2D). The patient underwent excisions of all 3 KAs, and free surgical margins were obtained.

Cipollaro¹⁰ reported the first case of a KA in a tattoo in 1973. Although there have been reports of melanoma and basal cell carcinoma occurring within tattoos, KAs and conventional SCCs are the most common cutaneous neoplasms arising in tattoos.

The pathogenesis underlying the development of malignancies in tattoos is unclear. It has been hypothesized that trauma from tattooing may play a role given the temporal relationship between tattoo placement and malignancy development.¹¹ Another theory is that tattoo pigment causes a chronic inflammatory foreign body reaction that triggers carcinogenesis.¹² Lastly, it has been postulated that tattoo pigment may alter UV light absorption in the skin that could potentially impact mutagenesis.¹¹

The most common treatment of KAs is standard surgical excision.⁴ Mohs micrographic surgery is an option if the KA is located in a cosmetically sensitive area. Although there are no reports of recurrence after excision of tattoo-related KAs, new KAs forming adjacent to a previously excised KA have been reported.¹³

Currently, tattoos are not regulated by the US Food and Drug Administration before going to market. Although many states regulate the practice of tattooing, few regulate the contents of tattoo ink, and ink is only investigated when safety issues arise.¹⁴ This case provides further evidence of an association between KAs, tattooing, and potentially carcinogenic pigments, especially in red dye, supporting the need for further research on the safety of pigment components and more regulation of tattoo ink.

To the Editor:

Keratoacanthoma (KA)–type squamous cell carcinomas (SCCs) are rapidly evolving neoplasms of the epithelium that often spontaneously regress but rarely metastasize.^1,2 Keratoacanthomas are thought to ascend from the hair follicle,¹ and they clinically present as an enlarging solitary crateriform nodule with a keratin-filled center. Multiple KAs are rare²; histologically, KAs can be difficult to distinguish from conventional SCCs and are frequently treated by standard surgical excision.¹ Reactive KAs are a subtype of KA that are induced by trauma including UV exposure, electromagnetic radiation, surgical procedures, chemical peels, laser treatments, and rarely tattoos.^3-5

A 56-year-old man presented to the clinic with 3 asymptomatic enlarging papulonodules within a multicolored tattoo along the right forearm and elbow of 5 months’ duration (Figure 1). The lesions developed 1 month after the tattoo was placed and were localized to the areas of red pigment. The patient had several other tattoos. Histologic examination of the lesions revealed a well-differentiated squamous neoplasm with a crateriform invagination consistent with the superficial portion of a KA (Figures 2A–C). The specimen also revealed exogenous red pigment that was consistent with the background tattoo (Figure 2D). The patient underwent excisions of all 3 KAs, and free surgical margins were obtained.

Cipollaro¹⁰ reported the first case of a KA in a tattoo in 1973. Although there have been reports of melanoma and basal cell carcinoma occurring within tattoos, KAs and conventional SCCs are the most common cutaneous neoplasms arising in tattoos.

The pathogenesis underlying the development of malignancies in tattoos is unclear. It has been hypothesized that trauma from tattooing may play a role given the temporal relationship between tattoo placement and malignancy development.¹¹ Another theory is that tattoo pigment causes a chronic inflammatory foreign body reaction that triggers carcinogenesis.¹² Lastly, it has been postulated that tattoo pigment may alter UV light absorption in the skin that could potentially impact mutagenesis.¹¹

The most common treatment of KAs is standard surgical excision.⁴ Mohs micrographic surgery is an option if the KA is located in a cosmetically sensitive area. Although there are no reports of recurrence after excision of tattoo-related KAs, new KAs forming adjacent to a previously excised KA have been reported.¹³

Currently, tattoos are not regulated by the US Food and Drug Administration before going to market. Although many states regulate the practice of tattooing, few regulate the contents of tattoo ink, and ink is only investigated when safety issues arise.¹⁴ This case provides further evidence of an association between KAs, tattooing, and potentially carcinogenic pigments, especially in red dye, supporting the need for further research on the safety of pigment components and more regulation of tattoo ink.

To the Editor:

Keratoacanthoma (KA)–type squamous cell carcinomas (SCCs) are rapidly evolving neoplasms of the epithelium that often spontaneously regress but rarely metastasize.^1,2 Keratoacanthomas are thought to ascend from the hair follicle,¹ and they clinically present as an enlarging solitary crateriform nodule with a keratin-filled center. Multiple KAs are rare²; histologically, KAs can be difficult to distinguish from conventional SCCs and are frequently treated by standard surgical excision.¹ Reactive KAs are a subtype of KA that are induced by trauma including UV exposure, electromagnetic radiation, surgical procedures, chemical peels, laser treatments, and rarely tattoos.^3-5

A 56-year-old man presented to the clinic with 3 asymptomatic enlarging papulonodules within a multicolored tattoo along the right forearm and elbow of 5 months’ duration (Figure 1). The lesions developed 1 month after the tattoo was placed and were localized to the areas of red pigment. The patient had several other tattoos. Histologic examination of the lesions revealed a well-differentiated squamous neoplasm with a crateriform invagination consistent with the superficial portion of a KA (Figures 2A–C). The specimen also revealed exogenous red pigment that was consistent with the background tattoo (Figure 2D). The patient underwent excisions of all 3 KAs, and free surgical margins were obtained.

Cipollaro¹⁰ reported the first case of a KA in a tattoo in 1973. Although there have been reports of melanoma and basal cell carcinoma occurring within tattoos, KAs and conventional SCCs are the most common cutaneous neoplasms arising in tattoos.

The pathogenesis underlying the development of malignancies in tattoos is unclear. It has been hypothesized that trauma from tattooing may play a role given the temporal relationship between tattoo placement and malignancy development.¹¹ Another theory is that tattoo pigment causes a chronic inflammatory foreign body reaction that triggers carcinogenesis.¹² Lastly, it has been postulated that tattoo pigment may alter UV light absorption in the skin that could potentially impact mutagenesis.¹¹

The most common treatment of KAs is standard surgical excision.⁴ Mohs micrographic surgery is an option if the KA is located in a cosmetically sensitive area. Although there are no reports of recurrence after excision of tattoo-related KAs, new KAs forming adjacent to a previously excised KA have been reported.¹³

Currently, tattoos are not regulated by the US Food and Drug Administration before going to market. Although many states regulate the practice of tattooing, few regulate the contents of tattoo ink, and ink is only investigated when safety issues arise.¹⁴ This case provides further evidence of an association between KAs, tattooing, and potentially carcinogenic pigments, especially in red dye, supporting the need for further research on the safety of pigment components and more regulation of tattoo ink.

The practice of dermatology is rife with bedside tools: swabs, smears, and scoring systems. First popularized in specialties such as emergency medicine and internal medicine, clinical scoring systems are now emerging in dermatology. These evidence-based scores can be calculated quickly at the bedside—often through a free smartphone app—to help guide clinical decision-making regarding diagnosis, prognosis, and management. As with any medical tool, scoring systems have limitations and should be used as a supplement, not substitute, for one’s clinical judgement. This article reviews 4 clinical scoring systems practical for dermatology residents.

SCORTEN Prognosticates Cases of Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis

Perhaps the best-known scoring system in dermatology, the SCORTEN is widely used to predict hospital mortality from Stevens-Johnson syndrome/toxic epidermal necrolysis. The SCORTEN includes 7 variables of equal weight—age of 40 years or older, heart rate of 120 beats per minute or more, cancer/hematologic malignancy, involved body surface area (BSA) greater than 10%, serum urea greater than 10 mmol/L, serum bicarbonate less than 20 mmol/L, and serum glucose greater than 14 mmol/L—each contributing 1 point to the overall score if present.¹ The involved BSA is defined as the sum of detached and detachable epidermis.¹

The SCORTEN was developed and prospectively validated to be calculated at the end of the first 24 hours of admission; for this calculation, use the BSA affected at that time, and use the most abnormal values during the first 24 hours of admission for the other variables.¹ In addition, a follow-up study including some of the original coauthors recommends recalculating the SCORTEN at the end of hospital day 3, having found that the score’s predictive value was better on this day than hospital days 1, 2, 4, or 5.² Based on the original study, a SCORTEN of 0 to 1 corresponds to a mortality rate of 3.2%, 2 to 12.1%, 3 to 35.3%, 4 to 58.3%, and 5 or greater to 90.0%.¹

Limitations of the SCORTEN include its ability to overestimate or underestimate mortality as demonstrated by 2 multi-institutional cohorts.^3,4 Recently, the ABCD-10 score was developed as an alternative to the SCORTEN and was found to predict mortality similarly when validated in an internal cohort.⁵

PEST Screens for Psoriatic Arthritis

Dermatologists play an important role in screening for psoriatic arthritis, as an estimated 1 in 5 patients with psoriasis have psoriatic arthritis.⁶ To this end, several screening tools have been developed to help differentiate psoriatic arthritis from other arthritides. Joint guidelines from the American Academy of Dermatology and the National Psoriasis Foundation acknowledge that “. . . these screening tools have tended to perform less well when tested in groups of people other than those for which they were originally developed. As such, their usefulness in routine clinical practice remains controversial.”⁷ Nevertheless, the guidelines state, “[b]ecause screening and early detection of inflammatory arthritis are essential to optimize patient [quality of life] and reduce morbidity, providers may consider using a formal screening tool of their choice.”⁷

With these limitations in mind, I have found the Psoriasis Epidemiology Screening Tool (PEST) to be the most useful psoriatic arthritis screening tool. One study determined that the PEST has the best trade-off between sensitivity and specificity compared to 2 other psoriatic arthritis screening tools, the Psoriatic Arthritis Screening and Evaluation (PASE) and the Early Arthritis for Psoriatic Patients (EARP).⁸

The PEST is comprised of 5 questions: (1) Have you ever had a swollen joint (or joints)? (2) Has a doctor ever told you that you have arthritis? (3) Do your fingernails or toenails have holes or pits? (4) Have you had pain in your heel? (5) Have you had a finger or toe that was completely swollen and painful for no apparent reason? According to the PEST, a referral to a rheumatologist should be considered for patients answering yes to 3 or more questions, which is 97% sensitive and 79% specific for psoriatic arthritis.⁹ Patients who answer yes to fewer than 3 questions should still be referred to a rheumatologist if there is a strong clinical suspicion of psoriatic arthritis.¹⁰

The PEST can be accessed for free in 13 languages via the GRAPPA (Group for Research and Assessment of Psoriasis and Psoriatic Arthritis) app as well as downloaded for free from the National Psoriasis Foundation’s website (https://www.psoriasis.org/psa-screening/providers).

ALT-70 Differentiates Cellulitis From Pseudocellulitis

Overdiagnosing cellulitis in the United States has been estimated to result in up to 130,000 unnecessary hospitalizations and up to $515 million in avoidable health care spending.¹¹ Dermatologists are in a unique position to help fix this issue. In one retrospective study of 1430 inpatient dermatology consultations, 74.32% of inpatients evaluated for presumed cellulitis by a dermatologist were instead diagnosed with a cellulitis mimicker (ie, pseudocellulitis), such as stasis dermatitis or contact dermatitis.¹²

The ALT-70 score was developed and prospectively validated to help differentiate lower extremity cellulitis from pseudocellulitis in adult patients in the emergency department (ED).¹³ In addition, the score has retrospectively been shown to function similarly in the inpatient setting when calculated at 24 and 48 hours after ED presentation.¹⁴ Although the ALT-70 score was designed for use by frontline clinicians prior to dermatology consultation, I also have found it helpful to calculate as a consultant, as it provides an objective measure of risk to communicate to the primary team in support of one diagnosis or another.

ALT-70 is an acronym for the score’s 4 variables: asymmetry, leukocytosis, tachycardia, and age of 70 years or older.¹⁵ If present, each variable confers a certain number of points to the final score: 3 points for asymmetry (defined as unilateral leg involvement), 1 point for leukocytosis (white blood cell count ≥10,000/μL), 1 point for tachycardia (≥90 beats per minute), and 2 points for age of 70 years or older. An ALT-70 score of 0 to 2 corresponds to an 83.3% or greater chance of pseudocellulitis, suggesting that the diagnosis of cellulitis be reconsidered. A score of 3 to 4 is indeterminate, and additional information such as a dermatology consultation should be pursued. A score of 5 to 7 corresponds to an 82.2% or greater chance of cellulitis, signifying that empiric treatment with antibiotics be considered.¹⁵

The ALT-70 score does not apply to cases involving areas other than the lower extremities; intravenous antibiotic use within 48 hours before ED presentation; surgery within the last 30 days; abscess; penetrating trauma; burn; or known history of osteomyelitis, diabetic ulcer, or indwelling hardware at the site of infection.¹⁵ The ALT-70 score is available for free via the MDCalc app and website (https://www.mdcalc.com/alt-70-score-cellulitis).

Mohs AUC Determines the Appropriateness of Mohs Micrographic Surgery

In 2012, the American Academy of Dermatology, American College of Mohs Surgery, American Society for Dermatologic Surgery Association, and American Society for Mohs Surgery published appropriate use criteria (AUC) to guide the decision to pursue Mohs micrographic surgery (MMS) in the United States.¹⁶ Based on various tumor and patient characteristics, the Mohs AUC assign scores to 270 different clinical scenarios. A score of 1 to 3 signifies that MMS is inappropriate and generally not considered acceptable. A score 4 to 6 indicates that the appropriateness of MMS is uncertain. A score 7 to 9 means that MMS is appropriate and generally considered acceptable.¹⁶

Since publication, the Mohs AUC have been criticized for classifying most primary superficial basal cell carcinomas as appropriate for MMS¹⁷ (which an AUC coauthor¹⁸ and others^19,20 have defended), excluding certain reasons for performing MMS (such as operating on multiple tumors on the same day),²¹ including counterintuitive scores,²² and omitting trials from Europe²³ (which AUC coauthors also have defended²⁴). As with any clinical scoring system, the Mohs AUC has limitations; the creators acknowledge that “. . . these criteria should not be interpreted as setting a standard of care, or be deemed inclusive of all proper methods of care nor exclusive of other methods of care reasonably directed to obtaining the same results, even for those indications scored as inappropriate.”¹⁶ The Mohs AUC app (https://www.aad.org/members/aad-apps/mohs-auc) is free and allows users to enter tumor and patient characteristics to determine the score for their specific scenario.

Final Thoughts

Scoring systems are emerging in dermatology as evidence-based bedside tools to help guide clinical decision-making. Despite their limitations, these scores have the potential to make a meaningful impact in dermatology as they have in other specialties.

The practice of dermatology is rife with bedside tools: swabs, smears, and scoring systems. First popularized in specialties such as emergency medicine and internal medicine, clinical scoring systems are now emerging in dermatology. These evidence-based scores can be calculated quickly at the bedside—often through a free smartphone app—to help guide clinical decision-making regarding diagnosis, prognosis, and management. As with any medical tool, scoring systems have limitations and should be used as a supplement, not substitute, for one’s clinical judgement. This article reviews 4 clinical scoring systems practical for dermatology residents.

SCORTEN Prognosticates Cases of Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis

Perhaps the best-known scoring system in dermatology, the SCORTEN is widely used to predict hospital mortality from Stevens-Johnson syndrome/toxic epidermal necrolysis. The SCORTEN includes 7 variables of equal weight—age of 40 years or older, heart rate of 120 beats per minute or more, cancer/hematologic malignancy, involved body surface area (BSA) greater than 10%, serum urea greater than 10 mmol/L, serum bicarbonate less than 20 mmol/L, and serum glucose greater than 14 mmol/L—each contributing 1 point to the overall score if present.¹ The involved BSA is defined as the sum of detached and detachable epidermis.¹

The SCORTEN was developed and prospectively validated to be calculated at the end of the first 24 hours of admission; for this calculation, use the BSA affected at that time, and use the most abnormal values during the first 24 hours of admission for the other variables.¹ In addition, a follow-up study including some of the original coauthors recommends recalculating the SCORTEN at the end of hospital day 3, having found that the score’s predictive value was better on this day than hospital days 1, 2, 4, or 5.² Based on the original study, a SCORTEN of 0 to 1 corresponds to a mortality rate of 3.2%, 2 to 12.1%, 3 to 35.3%, 4 to 58.3%, and 5 or greater to 90.0%.¹

Limitations of the SCORTEN include its ability to overestimate or underestimate mortality as demonstrated by 2 multi-institutional cohorts.^3,4 Recently, the ABCD-10 score was developed as an alternative to the SCORTEN and was found to predict mortality similarly when validated in an internal cohort.⁵

PEST Screens for Psoriatic Arthritis

Dermatologists play an important role in screening for psoriatic arthritis, as an estimated 1 in 5 patients with psoriasis have psoriatic arthritis.⁶ To this end, several screening tools have been developed to help differentiate psoriatic arthritis from other arthritides. Joint guidelines from the American Academy of Dermatology and the National Psoriasis Foundation acknowledge that “. . . these screening tools have tended to perform less well when tested in groups of people other than those for which they were originally developed. As such, their usefulness in routine clinical practice remains controversial.”⁷ Nevertheless, the guidelines state, “[b]ecause screening and early detection of inflammatory arthritis are essential to optimize patient [quality of life] and reduce morbidity, providers may consider using a formal screening tool of their choice.”⁷

With these limitations in mind, I have found the Psoriasis Epidemiology Screening Tool (PEST) to be the most useful psoriatic arthritis screening tool. One study determined that the PEST has the best trade-off between sensitivity and specificity compared to 2 other psoriatic arthritis screening tools, the Psoriatic Arthritis Screening and Evaluation (PASE) and the Early Arthritis for Psoriatic Patients (EARP).⁸

The PEST is comprised of 5 questions: (1) Have you ever had a swollen joint (or joints)? (2) Has a doctor ever told you that you have arthritis? (3) Do your fingernails or toenails have holes or pits? (4) Have you had pain in your heel? (5) Have you had a finger or toe that was completely swollen and painful for no apparent reason? According to the PEST, a referral to a rheumatologist should be considered for patients answering yes to 3 or more questions, which is 97% sensitive and 79% specific for psoriatic arthritis.⁹ Patients who answer yes to fewer than 3 questions should still be referred to a rheumatologist if there is a strong clinical suspicion of psoriatic arthritis.¹⁰

The PEST can be accessed for free in 13 languages via the GRAPPA (Group for Research and Assessment of Psoriasis and Psoriatic Arthritis) app as well as downloaded for free from the National Psoriasis Foundation’s website (https://www.psoriasis.org/psa-screening/providers).

ALT-70 Differentiates Cellulitis From Pseudocellulitis

Overdiagnosing cellulitis in the United States has been estimated to result in up to 130,000 unnecessary hospitalizations and up to $515 million in avoidable health care spending.¹¹ Dermatologists are in a unique position to help fix this issue. In one retrospective study of 1430 inpatient dermatology consultations, 74.32% of inpatients evaluated for presumed cellulitis by a dermatologist were instead diagnosed with a cellulitis mimicker (ie, pseudocellulitis), such as stasis dermatitis or contact dermatitis.¹²

The ALT-70 score was developed and prospectively validated to help differentiate lower extremity cellulitis from pseudocellulitis in adult patients in the emergency department (ED).¹³ In addition, the score has retrospectively been shown to function similarly in the inpatient setting when calculated at 24 and 48 hours after ED presentation.¹⁴ Although the ALT-70 score was designed for use by frontline clinicians prior to dermatology consultation, I also have found it helpful to calculate as a consultant, as it provides an objective measure of risk to communicate to the primary team in support of one diagnosis or another.

ALT-70 is an acronym for the score’s 4 variables: asymmetry, leukocytosis, tachycardia, and age of 70 years or older.¹⁵ If present, each variable confers a certain number of points to the final score: 3 points for asymmetry (defined as unilateral leg involvement), 1 point for leukocytosis (white blood cell count ≥10,000/μL), 1 point for tachycardia (≥90 beats per minute), and 2 points for age of 70 years or older. An ALT-70 score of 0 to 2 corresponds to an 83.3% or greater chance of pseudocellulitis, suggesting that the diagnosis of cellulitis be reconsidered. A score of 3 to 4 is indeterminate, and additional information such as a dermatology consultation should be pursued. A score of 5 to 7 corresponds to an 82.2% or greater chance of cellulitis, signifying that empiric treatment with antibiotics be considered.¹⁵

The ALT-70 score does not apply to cases involving areas other than the lower extremities; intravenous antibiotic use within 48 hours before ED presentation; surgery within the last 30 days; abscess; penetrating trauma; burn; or known history of osteomyelitis, diabetic ulcer, or indwelling hardware at the site of infection.¹⁵ The ALT-70 score is available for free via the MDCalc app and website (https://www.mdcalc.com/alt-70-score-cellulitis).

Mohs AUC Determines the Appropriateness of Mohs Micrographic Surgery

In 2012, the American Academy of Dermatology, American College of Mohs Surgery, American Society for Dermatologic Surgery Association, and American Society for Mohs Surgery published appropriate use criteria (AUC) to guide the decision to pursue Mohs micrographic surgery (MMS) in the United States.¹⁶ Based on various tumor and patient characteristics, the Mohs AUC assign scores to 270 different clinical scenarios. A score of 1 to 3 signifies that MMS is inappropriate and generally not considered acceptable. A score 4 to 6 indicates that the appropriateness of MMS is uncertain. A score 7 to 9 means that MMS is appropriate and generally considered acceptable.¹⁶

Since publication, the Mohs AUC have been criticized for classifying most primary superficial basal cell carcinomas as appropriate for MMS¹⁷ (which an AUC coauthor¹⁸ and others^19,20 have defended), excluding certain reasons for performing MMS (such as operating on multiple tumors on the same day),²¹ including counterintuitive scores,²² and omitting trials from Europe²³ (which AUC coauthors also have defended²⁴). As with any clinical scoring system, the Mohs AUC has limitations; the creators acknowledge that “. . . these criteria should not be interpreted as setting a standard of care, or be deemed inclusive of all proper methods of care nor exclusive of other methods of care reasonably directed to obtaining the same results, even for those indications scored as inappropriate.”¹⁶ The Mohs AUC app (https://www.aad.org/members/aad-apps/mohs-auc) is free and allows users to enter tumor and patient characteristics to determine the score for their specific scenario.

Final Thoughts

Scoring systems are emerging in dermatology as evidence-based bedside tools to help guide clinical decision-making. Despite their limitations, these scores have the potential to make a meaningful impact in dermatology as they have in other specialties.

The practice of dermatology is rife with bedside tools: swabs, smears, and scoring systems. First popularized in specialties such as emergency medicine and internal medicine, clinical scoring systems are now emerging in dermatology. These evidence-based scores can be calculated quickly at the bedside—often through a free smartphone app—to help guide clinical decision-making regarding diagnosis, prognosis, and management. As with any medical tool, scoring systems have limitations and should be used as a supplement, not substitute, for one’s clinical judgement. This article reviews 4 clinical scoring systems practical for dermatology residents.

SCORTEN Prognosticates Cases of Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis

Perhaps the best-known scoring system in dermatology, the SCORTEN is widely used to predict hospital mortality from Stevens-Johnson syndrome/toxic epidermal necrolysis. The SCORTEN includes 7 variables of equal weight—age of 40 years or older, heart rate of 120 beats per minute or more, cancer/hematologic malignancy, involved body surface area (BSA) greater than 10%, serum urea greater than 10 mmol/L, serum bicarbonate less than 20 mmol/L, and serum glucose greater than 14 mmol/L—each contributing 1 point to the overall score if present.¹ The involved BSA is defined as the sum of detached and detachable epidermis.¹

The SCORTEN was developed and prospectively validated to be calculated at the end of the first 24 hours of admission; for this calculation, use the BSA affected at that time, and use the most abnormal values during the first 24 hours of admission for the other variables.¹ In addition, a follow-up study including some of the original coauthors recommends recalculating the SCORTEN at the end of hospital day 3, having found that the score’s predictive value was better on this day than hospital days 1, 2, 4, or 5.² Based on the original study, a SCORTEN of 0 to 1 corresponds to a mortality rate of 3.2%, 2 to 12.1%, 3 to 35.3%, 4 to 58.3%, and 5 or greater to 90.0%.¹

Limitations of the SCORTEN include its ability to overestimate or underestimate mortality as demonstrated by 2 multi-institutional cohorts.^3,4 Recently, the ABCD-10 score was developed as an alternative to the SCORTEN and was found to predict mortality similarly when validated in an internal cohort.⁵

PEST Screens for Psoriatic Arthritis

Dermatologists play an important role in screening for psoriatic arthritis, as an estimated 1 in 5 patients with psoriasis have psoriatic arthritis.⁶ To this end, several screening tools have been developed to help differentiate psoriatic arthritis from other arthritides. Joint guidelines from the American Academy of Dermatology and the National Psoriasis Foundation acknowledge that “. . . these screening tools have tended to perform less well when tested in groups of people other than those for which they were originally developed. As such, their usefulness in routine clinical practice remains controversial.”⁷ Nevertheless, the guidelines state, “[b]ecause screening and early detection of inflammatory arthritis are essential to optimize patient [quality of life] and reduce morbidity, providers may consider using a formal screening tool of their choice.”⁷

With these limitations in mind, I have found the Psoriasis Epidemiology Screening Tool (PEST) to be the most useful psoriatic arthritis screening tool. One study determined that the PEST has the best trade-off between sensitivity and specificity compared to 2 other psoriatic arthritis screening tools, the Psoriatic Arthritis Screening and Evaluation (PASE) and the Early Arthritis for Psoriatic Patients (EARP).⁸

The PEST is comprised of 5 questions: (1) Have you ever had a swollen joint (or joints)? (2) Has a doctor ever told you that you have arthritis? (3) Do your fingernails or toenails have holes or pits? (4) Have you had pain in your heel? (5) Have you had a finger or toe that was completely swollen and painful for no apparent reason? According to the PEST, a referral to a rheumatologist should be considered for patients answering yes to 3 or more questions, which is 97% sensitive and 79% specific for psoriatic arthritis.⁹ Patients who answer yes to fewer than 3 questions should still be referred to a rheumatologist if there is a strong clinical suspicion of psoriatic arthritis.¹⁰

The PEST can be accessed for free in 13 languages via the GRAPPA (Group for Research and Assessment of Psoriasis and Psoriatic Arthritis) app as well as downloaded for free from the National Psoriasis Foundation’s website (https://www.psoriasis.org/psa-screening/providers).

ALT-70 Differentiates Cellulitis From Pseudocellulitis

Overdiagnosing cellulitis in the United States has been estimated to result in up to 130,000 unnecessary hospitalizations and up to $515 million in avoidable health care spending.¹¹ Dermatologists are in a unique position to help fix this issue. In one retrospective study of 1430 inpatient dermatology consultations, 74.32% of inpatients evaluated for presumed cellulitis by a dermatologist were instead diagnosed with a cellulitis mimicker (ie, pseudocellulitis), such as stasis dermatitis or contact dermatitis.¹²

The ALT-70 score was developed and prospectively validated to help differentiate lower extremity cellulitis from pseudocellulitis in adult patients in the emergency department (ED).¹³ In addition, the score has retrospectively been shown to function similarly in the inpatient setting when calculated at 24 and 48 hours after ED presentation.¹⁴ Although the ALT-70 score was designed for use by frontline clinicians prior to dermatology consultation, I also have found it helpful to calculate as a consultant, as it provides an objective measure of risk to communicate to the primary team in support of one diagnosis or another.

ALT-70 is an acronym for the score’s 4 variables: asymmetry, leukocytosis, tachycardia, and age of 70 years or older.¹⁵ If present, each variable confers a certain number of points to the final score: 3 points for asymmetry (defined as unilateral leg involvement), 1 point for leukocytosis (white blood cell count ≥10,000/μL), 1 point for tachycardia (≥90 beats per minute), and 2 points for age of 70 years or older. An ALT-70 score of 0 to 2 corresponds to an 83.3% or greater chance of pseudocellulitis, suggesting that the diagnosis of cellulitis be reconsidered. A score of 3 to 4 is indeterminate, and additional information such as a dermatology consultation should be pursued. A score of 5 to 7 corresponds to an 82.2% or greater chance of cellulitis, signifying that empiric treatment with antibiotics be considered.¹⁵

The ALT-70 score does not apply to cases involving areas other than the lower extremities; intravenous antibiotic use within 48 hours before ED presentation; surgery within the last 30 days; abscess; penetrating trauma; burn; or known history of osteomyelitis, diabetic ulcer, or indwelling hardware at the site of infection.¹⁵ The ALT-70 score is available for free via the MDCalc app and website (https://www.mdcalc.com/alt-70-score-cellulitis).

Mohs AUC Determines the Appropriateness of Mohs Micrographic Surgery

In 2012, the American Academy of Dermatology, American College of Mohs Surgery, American Society for Dermatologic Surgery Association, and American Society for Mohs Surgery published appropriate use criteria (AUC) to guide the decision to pursue Mohs micrographic surgery (MMS) in the United States.¹⁶ Based on various tumor and patient characteristics, the Mohs AUC assign scores to 270 different clinical scenarios. A score of 1 to 3 signifies that MMS is inappropriate and generally not considered acceptable. A score 4 to 6 indicates that the appropriateness of MMS is uncertain. A score 7 to 9 means that MMS is appropriate and generally considered acceptable.¹⁶

Since publication, the Mohs AUC have been criticized for classifying most primary superficial basal cell carcinomas as appropriate for MMS¹⁷ (which an AUC coauthor¹⁸ and others^19,20 have defended), excluding certain reasons for performing MMS (such as operating on multiple tumors on the same day),²¹ including counterintuitive scores,²² and omitting trials from Europe²³ (which AUC coauthors also have defended²⁴). As with any clinical scoring system, the Mohs AUC has limitations; the creators acknowledge that “. . . these criteria should not be interpreted as setting a standard of care, or be deemed inclusive of all proper methods of care nor exclusive of other methods of care reasonably directed to obtaining the same results, even for those indications scored as inappropriate.”¹⁶ The Mohs AUC app (https://www.aad.org/members/aad-apps/mohs-auc) is free and allows users to enter tumor and patient characteristics to determine the score for their specific scenario.

Final Thoughts

Scoring systems are emerging in dermatology as evidence-based bedside tools to help guide clinical decision-making. Despite their limitations, these scores have the potential to make a meaningful impact in dermatology as they have in other specialties.

Women who accumulated more indoor tanning sessions over time significantly increased their risk for squamous cell cancer over women who never engaged in indoor tanning, based on data from 159,419 women.

Previous research has examined associations between indoor tanning and cutaneous melanoma, but an association between indoor tanning and squamous cell carcinoma (SCC) has not been well studied, wrote Simon Lergenmuller, MSc, of the University of Oslo, and colleagues.

In a prospective cohort study published in JAMA Dermatology, the researchers surveyed 159,419 women from the Norwegian Women and Cancer study. Of these, 95,552 women (69%) reported ever use of indoor tanning. The average age at study inclusion was 50 years. During an average of 17 years’ follow-up, 597 women developed SCC.

Overall, the risk of SCC increased with increasing numbers of indoor tanning sessions. The adjusted hazard ratio for most tanning sessions versus no tanning sessions was 1.83. “The association between cumulative exposure to indoor tanning and SCC risk was the same regardless of duration of use and age at initiation,” the researchers wrote.

The risk of SCC was significantly higher both among women with 10 years or less of tanning bed use and among those with more than 10 years of use, compared with never users (HRs, 1.41 and 1.43, respectively). Similarly, researchers found a significantly higher risk of SCC among women who started indoor tanning at age 30 years or older and those who started younger than 30 years, compared with never users (HRs, 1.36 and HR, 1.51, respectively).

No significant association appeared between age at initiation of indoor tanning and age at the time of SCC diagnosis.

The study findings were limited by several factors including the variation in UV radiation among tanning devices, the lack of data on men, and the retrospective collection of UV exposure data that likely led to some misclassification, the researchers noted.

However, the results were strengthened by the large sample size and support the association between increased exposure to indoor tanning and increased risk of SCC, they wrote. “Avoidance of indoor tanning may help prevent not only melanoma but also SCC, and our results support the development of policies that regulate indoor tanning.”

The study was supported by the Institute of Basic Medical Sciences, University of Oslo, and the Norwegian Cancer Society. The researchers had no financial conflicts to disclose.

SOURCE: Lergenmuller S et al. JAMA Dermatol. 2019 Oct 2. doi: 10.1001/jamadermatol.2019.2681.

Women who accumulated more indoor tanning sessions over time significantly increased their risk for squamous cell cancer over women who never engaged in indoor tanning, based on data from 159,419 women.

Previous research has examined associations between indoor tanning and cutaneous melanoma, but an association between indoor tanning and squamous cell carcinoma (SCC) has not been well studied, wrote Simon Lergenmuller, MSc, of the University of Oslo, and colleagues.

In a prospective cohort study published in JAMA Dermatology, the researchers surveyed 159,419 women from the Norwegian Women and Cancer study. Of these, 95,552 women (69%) reported ever use of indoor tanning. The average age at study inclusion was 50 years. During an average of 17 years’ follow-up, 597 women developed SCC.

Overall, the risk of SCC increased with increasing numbers of indoor tanning sessions. The adjusted hazard ratio for most tanning sessions versus no tanning sessions was 1.83. “The association between cumulative exposure to indoor tanning and SCC risk was the same regardless of duration of use and age at initiation,” the researchers wrote.

The risk of SCC was significantly higher both among women with 10 years or less of tanning bed use and among those with more than 10 years of use, compared with never users (HRs, 1.41 and 1.43, respectively). Similarly, researchers found a significantly higher risk of SCC among women who started indoor tanning at age 30 years or older and those who started younger than 30 years, compared with never users (HRs, 1.36 and HR, 1.51, respectively).

No significant association appeared between age at initiation of indoor tanning and age at the time of SCC diagnosis.

The study findings were limited by several factors including the variation in UV radiation among tanning devices, the lack of data on men, and the retrospective collection of UV exposure data that likely led to some misclassification, the researchers noted.

However, the results were strengthened by the large sample size and support the association between increased exposure to indoor tanning and increased risk of SCC, they wrote. “Avoidance of indoor tanning may help prevent not only melanoma but also SCC, and our results support the development of policies that regulate indoor tanning.”

The study was supported by the Institute of Basic Medical Sciences, University of Oslo, and the Norwegian Cancer Society. The researchers had no financial conflicts to disclose.

SOURCE: Lergenmuller S et al. JAMA Dermatol. 2019 Oct 2. doi: 10.1001/jamadermatol.2019.2681.

Women who accumulated more indoor tanning sessions over time significantly increased their risk for squamous cell cancer over women who never engaged in indoor tanning, based on data from 159,419 women.

Previous research has examined associations between indoor tanning and cutaneous melanoma, but an association between indoor tanning and squamous cell carcinoma (SCC) has not been well studied, wrote Simon Lergenmuller, MSc, of the University of Oslo, and colleagues.

In a prospective cohort study published in JAMA Dermatology, the researchers surveyed 159,419 women from the Norwegian Women and Cancer study. Of these, 95,552 women (69%) reported ever use of indoor tanning. The average age at study inclusion was 50 years. During an average of 17 years’ follow-up, 597 women developed SCC.

Overall, the risk of SCC increased with increasing numbers of indoor tanning sessions. The adjusted hazard ratio for most tanning sessions versus no tanning sessions was 1.83. “The association between cumulative exposure to indoor tanning and SCC risk was the same regardless of duration of use and age at initiation,” the researchers wrote.

The risk of SCC was significantly higher both among women with 10 years or less of tanning bed use and among those with more than 10 years of use, compared with never users (HRs, 1.41 and 1.43, respectively). Similarly, researchers found a significantly higher risk of SCC among women who started indoor tanning at age 30 years or older and those who started younger than 30 years, compared with never users (HRs, 1.36 and HR, 1.51, respectively).

No significant association appeared between age at initiation of indoor tanning and age at the time of SCC diagnosis.

The study findings were limited by several factors including the variation in UV radiation among tanning devices, the lack of data on men, and the retrospective collection of UV exposure data that likely led to some misclassification, the researchers noted.

However, the results were strengthened by the large sample size and support the association between increased exposure to indoor tanning and increased risk of SCC, they wrote. “Avoidance of indoor tanning may help prevent not only melanoma but also SCC, and our results support the development of policies that regulate indoor tanning.”

The study was supported by the Institute of Basic Medical Sciences, University of Oslo, and the Norwegian Cancer Society. The researchers had no financial conflicts to disclose.

SOURCE: Lergenmuller S et al. JAMA Dermatol. 2019 Oct 2. doi: 10.1001/jamadermatol.2019.2681.