Cases of pilomatrixoma (1,569), including 170 of our own cases, were analyzed. The incidence in dermatohistopathologic material is 1:824. For every three tumors in female patients, two are found in male patients. Forty percent of the pilomatrixomas arise before the age of 10, and more than 60% in the first two decades. Localization in decreasing frequency occurs in these areas: head, upper extremity, neck, trunk, and lower extremity. The incidence of multiple tumors is 3.5%. A fifth case of familial occurrence is reported.
Moehlenbeck FW. Pilomatrixoma (Calcifying Epithelioma)A Statistical Study. Arch Dermatol. 1973;108(4):532-534. doi:10.1001/archderm.1973.01620250020004