Coexisting Basal Cell Carcinoma and Squamous Cell Carcinoma in Congenital Nevus Sebaceous

Nevus sebaceous is a congenital epidermal hamartoma characterized by hyperplastic changes to the epidermis and adnexa. Nevus sebaceous is associated with an elevated risk of cutaneous neoplasms, most often benign; however, malignant neoplasms, most notably basal cell carcinoma, can also present in these patients. Although a rare occurrence, more often affecting adult patients, squamous cell carcinomas have also been reported to arise at the site of pre-existing nevus sebaceous. Herein we report a unique case of a patient with basal cell carcinoma and squamous cell carcinoma arising concurrently in the same nevus sebaceous.