Pilomatricoma associated with several hair follicles

We report two cases of pilomatricoma in which the neoplasm was connected with several hair follicles. A 17-year-old boy developed an erythematous nodule, 1 cm in diameter, in the right temporal region, histologically showing basophilic cells connected with at least two hair follicles. In the other case, a 20-year-old man had a centrally ulcerated tumor, 2 cm in diameter, in the left lower back. Basophilic cells proliferated in connection with at least six hair follicle-like structures, accompanied by the development of shadow cells underneath. The histopathologic findings in these two cases suggest the existence of a subset of pilomatricomas that involve several pre-existing hair follicles.