Image of the Week: Can you identify these cutaneous findings?

An otherwise healthy 50-year-old man presents to his new family physician with a rash that he has had for several years. He mentions that the skin eruption becomes erythematous and pruritic after exercising and when he scratches it. On examination, reddish-brown freckle-like macules are seen on his upper extremities, back, and abdomen. A skin biopsy reveals an increased number of ...