A case of ovarian dermoid cyst with malignant transformation perforated into the rectosigmoid colon and small intestine.

A 72-year-old female was admitted to hospital with diarrhea containing hair. The abdominal plain film showed teeth-like structures in the right lower quadrant. Barium enema and endoscopic examination were performed, and the results indicated a possible dermoid cyst perforated into the rectosigmoid colon and small intestine. The operation revealed a dermoid cyst of the right ovary perforated into the rectosigmoid colon and small intestine. Histopathologically, a dermoid cyst and in part well-differentiated squamous cell carcinoma invading the rectosigmoid and small intestine were demonstrated.