A man in his 60s presented for further evaluation of a right inguinal and scrotal lesion (Image 1). Medical history Non–insulin-dependent diabetes mellitus and hyperlipidemia controlled with oral medications Social history Non-smoker Monogamous and married for 30 years. Surgical history The patient had a history of prostate cancer treated with prostatectomy 4 years previously without evidence of recurrence and melanoma of the posterior neck treated with wide local excision Past treatment The rash initially started 4 years prior as a dime-sized, pink, scaly area in the right inguinal crease and was pruritic.

Results of a biopsy at the time were consistent with lichen simplex chronicus, and treatment with topical steroids was initiated. Since then, the rash had failed to resolve and the affected area had increased in size to its present dimensions. Examination Examination revealed a…