Perforating pilomatricoma on the upper eyelid.

We report a rare case of perforating pilomatricoma. A 50 x 40-mm oval nodule, with a whitish scale on its tip, developed on the left upper eyelid of a 43-year-old Japanese woman. There was no history of injury to the left upper eyelid. Histologic examination revealed typical microscopic features of pilomatricoma. In addition, however, an interesting phenomenon was observed: a portion of the tumor mass had extruded from the upper dermis to the skin surface through a perforating epidermal channel in the middle of the tumor. These findings are consistent with the diagnosis of perforating pilomatricoma.