Multiple pilomatricomas: Recurrent skin nodules in myotonic dystrophy

Abstract

Pilomatricoma is a relatively uncommon benign tumor derived from the matrix of hair follicles. Multiple pilomatricomas may arise sporadically or in association with other disease entities. These entities include myotonic dystrophy type-1, a multisystem disorder that confers increased susceptibility to developing neoplasms, as well as familial adenomatous polyposis-related syndromes (including Gardner syndrome) and others. Here we present two case reports of multiple pilomatricomas that were initially misidentified clinically. We discuss pilomatricoma as a differential diagnosis of multiple skin nodules, its association with myotonic dystrophy in one of two patients, and describe its distinguishing microscopic features. We emphasize the importance of screening patients with multiple pilomatricomas for various syndromes that predispose to malignancy.