A case of perforating pilomatricoma

Pilomatricoma is a rare skin neoplasm, most commonly seen in the head and neck region, and occurring in the first two decades of life. It is usually solitary and varies from 0.5 to 2 cm in diameter. Its etiology is unknown. Perforating pilomatricoma is a rare clinical variant that presents as a draining, crusted nodule or ulcer, and is reported to arise faster than the classic pilomatricoma. Herein, we report a case of 35-year-old female, who had a 4-month history of a growing mass on her leg. On physical examination, a 4-cm diameter, asymptomatic, erythematous, ulcerated mass was noted on the left anterio-lateral upper leg. The first histopathological analysis of a punch biopsy from the lesion was reported as basal cell carcinoma. Therefore, the lesion was totally excised. There were shadow cells, squamoid cells, and basaloid aggregations more prominently in the one area in the tumor. In addition, calcification, foreign body giant cells and inflammatory cells were present. Punch or excisional biopsies are preferred as a method of diagnosis for the majority of cutaneous neoplasms. If total excision is not the method of choice, multiple punch biopsies should be made from different areas in large skin tumors for correct diagnosis.