Pilomatrixoma of the head and neck.

Pilomatrixoma is an uncommon neoplasm which occurs most frequently in the head and neck region. It usually presents as a slowly growing dermal or subcutaneous mass. Unfamiliarity with this lesion may lead the physician to mistake it for more common infectious or neoplastic processes. Most pilomatrixomas are benign and are adequately treated by local excision. Since a spectrum of clinical and histologic aggressiveness (pilomatrixoma carcinoma) has been noted in some lesions, a more aggressive surgical approach for such tumors is recommended. Two patients with pilomatrixoma are presented to emphasize the diagnostic confusion that can occur.