Dermal eccrine cylindroma is a benign adnexal tumor that commonly affects the scalp, neck, and face. Malignant transformation is rare and has resulted in several cases of intracranial invasion. There have been no previously reported cases of a benign lesion eroding through the skull vault. We report the development of such a lesion in a woman who had undergone total scalp excision and resurfacing with a split skin graft some 23 years earlier. Details of the case and its management are presented.