Malherbe calcifying epithelioma or pilomatrichoma is a solitary benign calcifying tumor of the hair follicles. This is one of the most common acquired soft tissue lesions in children. 

Clinically, a circumscribed, firm, intracutaneous, or subcutaneous nodule with occasional yellowish or bluish coloration is palpable. Sixty to seventy percent of these lesions are found in the head and neck region. The extremities are also frequent locations, followed by the trunk. Most are less than 1 cm in size. Local excision is curative*, preferably after 3 years old.

* GW Holcomb, J Patrick Murphy, DJ Ostlie. Aschcraft´s Pediatric Surgery 6º Ed.