Trichilemmal Carcinoma of Scalp Masquerading as Squamous Cell Carcinoma: A Report of a Rare Case with Histogenesis and Literature Review.

Trichilemmal carcinoma is a rare malignant adnexal neoplasm of follicular type usually seen over the sun-exposed areas of elderly people. We present a report of a 60-year-old male with ulceroproliferative lesion over the occipital region of the scalp for 2 months, clinically diagnosed as squamous cell carcinoma. A wide local excision was done, and histopathological examination showed atypical clear cells with abrupt keratinization. The histogenesis and other differential diagnoses are discussed.