Ovarian tumors associated with atypical endometriosis.

We present five cases in which ovarian neoplasms (three clear cell carcinomas, two endometrioid carcinomas) were associated--and in four cases contiguous--with atypical glandular epithelial changes in endometriosis. This association has not been reported previously in the ovary, but four cases of extragonadal malignant tumors have been noted to occur with or after atypical endometriosis. We propose that a diagnosis of atypical endometriosis be followed by careful long-term observation of the patient to detect possible subsequent development of neoplasia.