Squamous cell carcinoma arising in a giant epidermal cyst of the perineum: a case report and literature review.

This case pertains to a 76-year-old woman with a giant cyst in the perineum. Extirpation was performed. The result of a pathological investigation was squamous cell carcinoma arising in an epidermal cyst. An epidermal cyst is necessary to conduct an examination bearing in mind the possibility of a malignant tumour.