Subungual Metastasis of an Adenocarcinoma of the Prostate in a Finger.

Cutaneous metastasis is a rare event occurring most frequently in patients previously diagnosed with cancer. However, subungual metastases are even less frequent. The most common neoplasms associated with the latter are lung, kidney, and breast neoplasms. Lung cancer is the main cause of subungual metastases in the fingers, and genitourinary tract tumors are the main cause of subungual metastases in the toes. This is the first case report of an adenocarcinoma of the prostate with subungual metastasis.