A man in his 50s was referred for evaluation of pruritic lesions in the perianal area and buttocks of 2 years’ duration. He reported no history of cutaneous diseases. He had undergone heterologous bone marrow transplantation for chronic myeloid leukemia 18 years before and had hypertension controlled with lisinopril and hydrochlorothiazide and type 2 diabetes mellitus controlled by diet. Physical examination revealed multiple hyperkeratotic purplish brown papules and plaques, more confluent in the perianal area, with well-demarcated keratotic prominent margins (Figure, A and B). Dermoscopy showed structureless brownish pigmentation and erythema in the center, demarcated by a white-yellow hyperkeratotic scale at the periphery. Because of suspicion of lichen planus annularis, the patient was treated intermittently with intramuscular triamcinolone acetonide depot and topical treatments such as corticosteroids, antifungal agents, pimecrolimus, and retinoic acid, resulting in subjective pruritus relief; however, the lesions did not show satisfactory improvement in 2 years’ follow-up. Therefore, 2 skin biopsies were performed (Figure, C).
Collgros H, Iglesias-Sancho M, Aldunce-Soto M. Recalcitrant Papules and Plaques on Perianal Area and Buttocks. JAMA Dermatol. 2014;150(9):1007-1008. doi:10.1001/jamadermatol.2014.671