Basal Cell Carcinomas and Trichoblastomas Associated With Epidermal Nevus

We herein report a case of multiple basal cell carcinomas (BCCs) and trichoblastomas associated with a linear epidermal nevus.An 84-year-old woman had a large, brown papillomatous lesion on her back that had been present since birth and was diagnosed as a linear epidermal nevus 20 years earlier.A black papule first appeared 11 years earlier within the lesion and was diagnosed as basal cell carcinoma.Over the subsequent 13 years, approximately 40 similar papules appeared, 17 of which were diagnosed as basal cell carcinoma.However, upon retrospective review of the available histological slides, five of these lesions were rediagnosed as trichoblastoma.The association of basal cell carcinomas with epidermal nevus is rare, and trichoblastoma associated with an epidermal nevus has not been previously reported.Therefore, we described this unique case in detail.