Piloleiomyoma arising in an organoid nevus: a case report and review of the literature.

The case of a 59-year-old woman with a history of an organoid nevus of the scalp is reported. Histologic examination revealed multiple secondary tumors including a tumor of the follicular infundibulum, an apocrine nevus, a syringocystadenoma papilliferum, an apocrine adenoma, and a piloleiomyoma occurring in the absence of sebaceous glands. The types of secondary tumors which may develop within organoid nevi are reviewed. The terminology and pathogenesis of this hamartoma are discussed.