Malignant proliferating trichilemmal tumor: a case report and review of literature.

Proliferating trichilemmal tumor (PTT) is an uncommon appendageal skin tumor that affects mainly elderly women. It arises from the external root sheath of the hair follicle and is most commonly observed on the scalp. Although most cases pursue a favorable clinical course and surgical excision is curative, malignant transformation has rarely been reported in these lesions. Because of limited number of cases reported in the literature, management of malignant PTT is controversial and mainly entails wide local excision. Many other adjuvant modalities have been tried. In this report, we present a case of malignant PTT in a 65-year-old male patient who presented with ulceroproliferative growth over occipital region since 4 months.