Melanoma of the Foot: Often Overlooked

Seen here is an ulcerated tumor with irregular borders on the left foot of a 37-year-old man. He said the tumor had developed several years ago. Microscopic examination of an excisional biopsy specimen confirmed the diagnosis of melanoma, Clark level IV (invasive into the reticular dermis). Cytologically atypical melanocytes extended down from the epidermis into the dermis, and the periphery of the tumor showed pagetoid spread of the abnormal melanocytes into the adjacent epidermis.

A high-power micrograph of the tumor deep in the dermis shows cells with readily recognized characteristics of malignancy, including nuclear pleomorphism, nucleoli, irregular nuclear borders, clumped chromatin, and mitoses. Melanin pigment is seen in a few cells. These photos were sent by Dr John B. Williams of Sacramento, Calif, who reports that today, 4 years since the tumor was removed, the patient is healthy and has had no recurrences.