Organ transplant patients are at high risk of skin cancer because they take immune-suppressing drugs to prevent organ rejection. But few studies have focused on the skin cancer risks for transplant patients with dark skin types that usually are more resistant to sun damage.

A new study by Drexel University researchers that focused on nonwhite patients concludes that they need to have regular, total-body skin examinations as part of post-transplant care  because they are at high risk of nonmelanoma skin cancers, called basal cell and squamous cell cancers.  For black patients, a thorough inspection of areas such as the groin that don't get sun exposure is "imperative," Drexel dermatologist Christina Chung and her coauthors wrote this month in JAMA Dermatology.

The authors reviewed medical records for 259 nonwhite transplant patients and found that 15 of them, almost 6 percent, developed 19 nonmelanoma skin cancers. The cancers occurred in six black patients, five Asian patients, and four Hispanic patients.

Although nonmelanomas are far less deadly than melanoma, they can grow and become life-threatening without treatment, especially in immune-compromised patients. Basal and squamous cells cancers are linked to damage caused by sun exposure over many years, but it is not unheard-of for these to develop on sun-protected skin. Previous studies have linked some of these unusual skin cancers to infection with certain strains of the human papilloma virus (HPV).

In the Drexel study, all seven squamous cell cancers found in black patients were located on sun-protected sites such as the groin or genitalia, and these lesions tested positive for HPV. Fortunately, they  were also diagnosed at an early, highly curable stage.

"Nonwhite organ transplant patients represent a unique group with specialized medical needs; thus, more knowledge on risk factors, appropriate screening methods, and counseling points are essential for providing comprehensive dermatologic care," the authors wrote.

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