Malignant degeneration of benign cystic teratomas of the ovary. Review of the literature and report of a chondrosarcoma and carcinoid tumor.

The development of cancer in a pre-existing benign cystic teratoma of the ovary is rare. A total of 272 cases have now been recorded in the literature, although detailed reports are unavailable in 75. Excluding cases of doubtful classification, 93% of tumors were carcinomas and only 7% sarcomas. In the epithelial group squamous carcinoma was by far the most common (83%). The incidence of adenocarcinoma and argentaffinoma was approximately equal at 6%, although the number of cases of carcinoid tumor reported in recent years appears to be increasing. The present report tabulates the findings in 43 cases described since the last extensive review in 1957. The average age of patients was 55 years and the only symptom or sign was an abdominal mass, except when the tumor had extended through the cyst wall. Right and left ovaries were involved with equal frequency. Treatment varied from simple removal of the cyst to hysterectomy and bilateral salpingo-oophorectomy. In some inoperable cases only biopsy of the lesion was possible. Prognosis was poor when extension through the cyst wall had occurred and good otherwise. The first case of chondrosarcoma and the fourteenth case of carcinoid tumor arising in a benign cystic teratoma are reported.