A 50-year-old man came to the office with a 7-year history of a slowly growing lesion on his chest. The patient, an outdoor worker with excessive sun exposure for 20 years, had skin phototype IV (burns minimally, always tans well to moderately brown). He reported that this lesion has never healed, has bled on occasion, and that regular wound care over several months was ineffective. He had suffered no trauma, nor had he applied any caustic products to this area. The patient was otherwise healthy and was not taking any medications. His family history was not contributory.
Physical examination revealed a large plaque about 4.5 by 3 cm with irregular borders (FIGURE 1). It seemed to have been expanding centrifugally for a long time, with areas of skipping, individual nodules, and papules. Close exam showed central ulcerations and crusting on scattered papules and nodules (FIGURE 2). The borders were rolled up and had a somewhat pearly appearance with erythema and telangiectasia. The area immediately surrounding the plaque was also remarkable for faint erythema. The central part of the lesion was atrophic with pinkish discoloration; on finger pinching of the central, the skin seemed to be sclerotic. The rest of the skin, mucosal, adnexal examination and review of systems was unremarkable. No lymphadenopathy was present. A skin biopsy was done to confirm the clinical impression.
FIGURE 1
Pigmented plaque on chest
FIGURE 2
Close-up
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