Papules on hands and soles

Although these lesions were consistent with actinic keratosis, the location on the palms and the patient’s history of growing up on a ranch in northern Mexico (where he said he was exposed to high arsenic levels in the water and soil), suggested that this was a case of arsenical keratosis. A biopsy excluded frank squamous cell carcinoma; further testing was not needed to make the diagnosis.

While both actinic and arsenical keratoses are precancerous growths with delayed presentations of 20 to 30 years, arsenical keratoses do not typically appear in sun-exposed areas. Rather, these lesions appear on a patient’s palms or soles. They also may present as plate-like hyperpigmentation of the palms and soles or corn-like keratotic papules.

Arsenic occurs naturally in soil and groundwater worldwide and acts as a toxin and carcinogen. It accumulates in the skin, hair, nails, and teeth—making these sites markers of chronic disease. Chronic exposure leads to skin and lung cancer. Cancer of other organs also is possible. Peripheral neuropathy and pancytopenia are hallmarks of chronic exposure.

If arsenical keratosis is suspected, testing for arsenic levels in water or in the work environment is recommended. That said, arsenic exposure is often remote (given the time that has elapsed) and hard to prove.

A blood count and renal and liver function tests should be considered to assess for organ damage. In this case, these tests were normal and the patient was treated with cryotherapy and monitored for recurrence with annual skin exams. Oral retinoids, such as acitretin, have had success in suppressing the frequency and severity of episodes of new lesions in small case reports.

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Photos and text for Photo Rounds Friday courtesy of Jonathan Karnes, MD (copyright retained). Dr. Karnes is the medical director of MDFMR Dermatology Services, Augusta, ME.  

Although these lesions were consistent with actinic keratosis, the location on the palms and the patient’s history of growing up on a ranch in northern Mexico (where he said he was exposed to high arsenic levels in the water and soil), suggested that this was a case of arsenical keratosis. A biopsy excluded frank squamous cell carcinoma; further testing was not needed to make the diagnosis.

While both actinic and arsenical keratoses are precancerous growths with delayed presentations of 20 to 30 years, arsenical keratoses do not typically appear in sun-exposed areas. Rather, these lesions appear on a patient’s palms or soles. They also may present as plate-like hyperpigmentation of the palms and soles or corn-like keratotic papules.

Arsenic occurs naturally in soil and groundwater worldwide and acts as a toxin and carcinogen. It accumulates in the skin, hair, nails, and teeth—making these sites markers of chronic disease. Chronic exposure leads to skin and lung cancer. Cancer of other organs also is possible. Peripheral neuropathy and pancytopenia are hallmarks of chronic exposure.

If arsenical keratosis is suspected, testing for arsenic levels in water or in the work environment is recommended. That said, arsenic exposure is often remote (given the time that has elapsed) and hard to prove.

A blood count and renal and liver function tests should be considered to assess for organ damage. In this case, these tests were normal and the patient was treated with cryotherapy and monitored for recurrence with annual skin exams. Oral retinoids, such as acitretin, have had success in suppressing the frequency and severity of episodes of new lesions in small case reports.

‌

Photos and text for Photo Rounds Friday courtesy of Jonathan Karnes, MD (copyright retained). Dr. Karnes is the medical director of MDFMR Dermatology Services, Augusta, ME.  

Although these lesions were consistent with actinic keratosis, the location on the palms and the patient’s history of growing up on a ranch in northern Mexico (where he said he was exposed to high arsenic levels in the water and soil), suggested that this was a case of arsenical keratosis. A biopsy excluded frank squamous cell carcinoma; further testing was not needed to make the diagnosis.

While both actinic and arsenical keratoses are precancerous growths with delayed presentations of 20 to 30 years, arsenical keratoses do not typically appear in sun-exposed areas. Rather, these lesions appear on a patient’s palms or soles. They also may present as plate-like hyperpigmentation of the palms and soles or corn-like keratotic papules.

Arsenic occurs naturally in soil and groundwater worldwide and acts as a toxin and carcinogen. It accumulates in the skin, hair, nails, and teeth—making these sites markers of chronic disease. Chronic exposure leads to skin and lung cancer. Cancer of other organs also is possible. Peripheral neuropathy and pancytopenia are hallmarks of chronic exposure.

If arsenical keratosis is suspected, testing for arsenic levels in water or in the work environment is recommended. That said, arsenic exposure is often remote (given the time that has elapsed) and hard to prove.

A blood count and renal and liver function tests should be considered to assess for organ damage. In this case, these tests were normal and the patient was treated with cryotherapy and monitored for recurrence with annual skin exams. Oral retinoids, such as acitretin, have had success in suppressing the frequency and severity of episodes of new lesions in small case reports.

‌

Photos and text for Photo Rounds Friday courtesy of Jonathan Karnes, MD (copyright retained). Dr. Karnes is the medical director of MDFMR Dermatology Services, Augusta, ME.