Multiple tumour presentation of trichilemmal carcinoma

Abstract

Trichilemmal carcinoma is a rare skin tumour occurring in the sun-exposed areas of the elderly. It originates from the external root sheath of the hair follicle and is the malignant form of the trichilemmoma. Clinically, it may be mistaken for a squamous cell carcinoma, basal cell carcinoma, nodular melanoma or keratoacanthoma. It is distinct from the proliferating trichilemmal tumour. Trichilemmal carcinoma is usually a solitary lesion and an extensive literature search revealed no previously reported cases of multiple tumour presentation. We describe a case of trichilemmal carcinoma arising from three distinct sites in the same patient and discuss the differential diagnoses, histological features and probable aetiology of this rare tumour.