[Correlation between serious ovarian tumors and extra-ovarian peritoneal tumors of the same histology].

The occurrence of serous peritoneal tumors (SPT) with the same histology as serous neoplasms arising within the ovary is explained by the common origin of the peritoneum and the ovaries from the coelomic epithelium. They occur alone or in combination with analogous tumors of the ovary and are often misinterpreted as metastatic ovarian carcinomas. Their histology shows considerable variations. As lesions with and without invasive properties may coexist, visible lesions should be resected and examined as completely as possible. The prognostic significance of some histological findings is still under study. It appears that besides invasion the grade of nuclear atypia is of importance. It is therefore possible that the use of cytometry provides new prognostic criteria, allowing the identification of high risk groups. This holds also for the malignant forms of SPT, which seem to have a similar prognosis to analogous tumors of the ovary. For this purpose, peritoneal cytology is of special value and constitutes an integral part of the investigations.