[Low grade malignant ovarian carcinomas. A retrospective study of 132 cases].

OBJECTIVE: to estimate the frequency, the age, the size, the bilaterality and the prognosis for "borderline" tumours according to the type of cell found. MATERIAL STUDIED: 132 low grade malignant tumours found in 845 primary ovarian carcinomas diagnosed between 1975 and 1984 in the Institute of Pathology in Strasbourg. RESULTS: borderline serous carcinomas (63 cases) were 16.9% of cases were serous neoplasias. The mean age at which the diagnosis was made was 50.3 years of age, and the tumour measured 10 cm. They were bilateral in 20% of the cases and the mean age of survival was 134.7 months. The borderline mucinous carcinomas (68 cases) were 18.2% of mucinous neoplasias. The intestinal sub-variety was found at the mean age of 50 years and was 15.3 cm in diameter. It was rarely bilateral and in some cases was accompanied by peritoneal pseudomyxomatosis. The endocervical sub-variety (18 cases) was diagnosed at a mean age of 41.5 years with a mean size of 13.5 cm. It was rarely bilateral. The two varieties of borderline mucinous carcinomas had a mean survival rate of 154 months. Only one borderline endometrioid carcinoma was found among the 54 endometrioid carcinomas, and none had clear cells, Brenner cells or mixed cells. CONCLUSION: under the heading of "borderline" carcinoma are different types of tumour with different prognoses. Only serous mucinous varieties which are more frequent, have a low potential for becoming malignant. Endometrioid types and clear cell or Brenner types which have a similar architecture are usually found out to be benign.