Squamous cell carcinomas of the ovary: report of four cases and literature review.

Two cases of squamous cell carcinoma developing in mature cystic teratoma and two cases with a malignant change involving an ovarian epidermal cyst diagnosed in our institution over a 15-year-period are reported. This is a reminder that such changes may occur and issues regarding the problem of the differential diagnosis and management of these rare complications are discussed.