Trichilemmal carcinoma: an unusual presentation of a rare cutaneous lesion.

Trichilemmal carcinoma (TC) is a rare cutaneous neoplasm which is derived from adnexal keratinocytes, is histologically invasive, contains cytologically atypical clear cell neoplasm and is in continuity with the epidermis and/or follicular epithelium. However, the diagnostic criteria and even the existence of TC have been contentious. We report the case of a 92-year-old woman with TC of the head and neck region who presented with an unusually long history. She was treated successfully with wide local excision. Important aspects in presentation, differential diagnosis, including histopathological features and management are discussed.