A plaque under cover

A 58-year-old Chinese man with a history of noninsulin-dependent diabetes, hypertension, and hyperlipidemia presented with a nonitchy, nontender, enlarging erythematous plaque on his prepuce for the past two years. He had no casual sexual partners for the past 3 years and was able to retract his foreskin, with no dysuria or hematuria. He did not report easy bruising, arthralgia, fever, or weight loss. Examination revealed a 2 cm 9 1.8 cm indurated, dull, erythematous plaque on the penile prepuce with no involvement of the glans penis (Fig. 1). No lymphadenopathy was detected. His cardiovascular, abdominal, and neurological examinations were unremarkable. Skin biopsy was taken from the prepuce plaque (Fig. 2).