A case of morphea-like basal cell carcinoma arising from an epidermal cyst

Abstract

We report a case of morphea-like basal cell carcinoma arising from an epidermal cyst on the forehead. A 64-year-old man noticed a subcutaneous mass on his forehead 15 years ago. It ruptured spontaneously and then an open drainage treatment was performed after its diagnosis as an epidermal cyst. After one month, he visited our hospital because the wound was slow in healing. It was diagnosed histologically as a morphea-like basal cell carcinoma originating from an epidermal cyst. The cyst wall was partially replaced by the malignant tumor. According to the literature, basal cell carcinoma is apparently less common in association with an epidermal cyst than is squamous cell carcinoma. And as far as we know, the morphea-like type BCC has not been reported to date. [Skin Cancer (Japan) 2005 ; 20: 39-42]