REPORT OF A CASE
A 72-year-old white man was referred for evaluation and treatment of an inflamed skin tag on his neck. A thrombosed, erythematous, pedunculated skin tag was found on the left side of his neck. In addition, an erythematous, slightly scaly plaque with sharply but irregularly demarcated borders (3×5 cm) was found on the right upper abdomen (Figure 1 and Figure 2). The lesion was completely asymptomatic and of at least 1 year's duration. The rest of the skin examination was normal. The skin tag was removed with a shave excision. A punch biopsy specimen was taken from the indurated plaque; light microscopic findings from the specimen are shown in Figure 3 and Figure 4.What is your diagnosis?Figure 1.Figure 2.Figure 3.Figure 4.
HISTOPATHOLOGIC FINDINGS AND CLINICAL COURSE
Histopathologic findings revealed melanocytes with marked cytologic atypia scattered within the epidermis. The
Amster MS, Klaus MV. Amelanotic Melanoma. Arch Dermatol. 1995;131(8):953-954. doi:10.1001/archderm.1995.01690200091018