Endometrioid and clear cell carcinoma of the ovary

Abstract

Two hundred and thirty cases of primary ovarian carcinoma derived from the surface epithelium of the ovary were reviewed over a 30‐year period ending in 1960. Of these, 37 (16%) were classified as endometrioid and 12 (5%) as clear cell carcinomas. The 5‐ and 10‐year survival for patients with endometrioid carcinoma was 46% and 37%, respectively, and for those with clear cell carcinoma, 27% and 18%, respectively. Factors which proved to be quite useful in predicting the behavior of endometrioid carcinoma were the stage and grade of the tumor; the “purity” was of limited value. Stage I patients had a 69% and 63%, 5‐ and 10‐year survival; there were no Stage III and IV survivors. Patients with low‐grade tumors had a better prognosis than those with high‐grade tumors and those with “pure” tumors had a more favorable prognosis than those with “mixed” tumors. In analyzing clear cell carcinoma, it was noted that the stage was crucial since in those patients with tumor confined to the ovary the 5‐ and 10‐year survival was 50% compared to the overall survival of 27% and 18%. Our group of patients with endometrioid carcinoma was then combined with other series of endometrioid carcinoma reported in the literature over the past 10 years in order to put the statistics into clearer perspective. The mean incidence thus obtained was 18% and the mean 5‐year survival, 47%. Lastly, the histogenesis of clear cell carcinoma was studied in relation to endometriosis and endometrioid carcinoma. Four cases (11%) of endometrioid carcinoma were closely associated with and one case (8%) of clear cell carcinoma developed from endometriosis. The finding of clear cells mixed with all types of primary carcinoma of the ovary derived from the surface epithelium makes it appear that clear cell carcinoma, like endometrioid carcinoma, may on occasion develop from endometriosis but that more often it arises de novo from the surface epithelium of the ovary. Therefore, despite its relatively high association with endometriosis, the frequent combination of clear cell elements mixed with other primary ovarian carcinoma and its somewhat different prognosis lead us to conclude that clear cell and endometrioid carcinomas are related but distinct entities. Copyright © 1972 American Cancer Society