Pilomatrixcarcinoma of the Foot: A New Localization of an Extremely Rare Adnexal Tumour.

Pilomatrixcarcinoma is a very rare follicular neoplasm that shows matrical differentiation. The majority of these lesions originate de novo, while only a few cases of transformation of pilomatricoma (calcifying epithelioma of Malherbe) have been described in the literature. The neoplasm affects mostly middle-aged males with a male-to-female ratio of 3-4:1. The most common localizations are the face, head, trunk and extremites, though there are a few reports of pilomatrixcarcinoma of the eyelid, eyebrow, axilla and clitorid. Here, we describe the first case of a pilomatrixcarcinoma on the anterolateral surface of the first toe of the left foot of an 83-year-old patient, which developed in less than six months and led to amputation of the distal phalanx. We report a brief review of the current literature with particular emphasis on histopathological features useful for diagnosis.