Clinical experiences of pilimatrixoma in a single institution

Purpose: To describe the clinical presentations, management, and outcomes of patients with pilomatrixomas treated in a single institution, and to compare the clinicopathological features according to their location. Methods: We reviewed the medical records of 57patients treated between January 1986 and December 2007, retrospectively. Results: The 57patients had a total of 61 cases of pilomatrixomas. The mean age at diagnosis was 12.4 years, with most patients aged 0~10 years, followed by 10∼20 years and 20∼30 years.Mean tumor size was 1.46 cm, and most tumors were less than 2.0 cm in diameter. Forty-twotumors(68.9%) on the head and the neck were classified as Group I, and 19 tumors (31.1%) on thebody were classified as Group II. The mean age at diagnosis was 9.4 years in Group I,and 19.8 years in Group II with significant statistical difference (P=0.009). The mean duration of symptoms was 26.4 months in Group I, and 7.2 months in Group II (P=0.001). All patients were treated surgically, and two patients relapsed (5 months and 3 years later). Conclusion: Pilomatrixoma is an uncommon benign skin tumor arising from hair follicle matrixcells. Diagnosis is usually easy based on clinical findings, and preoperative diagnosis may be improved with increased awareness of pilomatrixoma. Complete surgical excision is the treatment of choice, and recurrence after complete excision is rare.