Malignancy arising in cystic ovarian teratomas. A report of 24 cases.

Twenty-four cases with a malignant change involving one of the elements of an ovarian dermoid cyst are reported. The patients were older than those with benign ovarian dermoid cysts. Squamous carcinoma was most frequent with adenocarcinoma, undifferentiated carcinoma and a fibrosarcoma also occurring. Survival time after diagnosis was less than 1 year in 75% of the cases.