Clinicopathological study of pilomatricoma.

OBJECTIVES To study the clinical and histopathologic spectrum of pilomatricoma, the benign tumor of hair matrix. METHODS Retrospective review of 27 cases of pilomatricoma (Calcifying epithelioma of Malherbe) reported at Bahrain Defence Force Hospital from 1993-1999. RESULTS Most of the cases were confused clinically with sebaceous cysts. Seventy eight per cent of the cases occurred below the age of 30 years. Female to male ratio was 5:4. Head, neck and upper limb were the most common sites for pilomatricoma. The size of the tumors ranged from between 4-35 mm in diameter. Tumors were encapsulated and solid composed of shadow and basophilic cells, and stroma containing varying amounts of calcification, ossification and inflammatory cells. CONCLUSIONS Pilomatricomas have a wide variety of clinical characteristics and are often misdiagnosed with other skin conditions. They should be considered along with other benign and malignant conditions in the clinical differential diagnosis of solitary firm skin nodules especially those, which occur in the head, neck and upper limb.