Biopathology of ovarian carcinomas early and advanced-stages: Article drafted from the French guidelines in oncology entitled “Initial management of patients with epithelial ovarian cancer” developed by FRANCOGYN, CNGOF, SFOG, GINECO-ARCAGY under the aegis of CNGOF and endorsed by INCa

Objectives: Ovarian carcinomas represent a heterogeneous group of lesions with specific therapeutic management for each histological subtype. Thus, the correct histological diagnosis is mandatory. Material and methods: References were searched by PubMed from January 2000 to January 2018 and original articles in French and English literature were selected. Results and conclusions: In case of ovarian mass suspicious for cancer, a frozen section analysis may be proposed, if it could impact the surgical management. A positive histological diagnosis of ovarian carcinoma (type and grade) has to be rendered on histological (and not cytological) material before any chemotherapy with multiples and large sized biopsies. In case of needle biopsy, at least three fragments with needles > 16G are needed. Histological biopsies need to be formalin-fixed (4% formaldehyde) less than 1 h after resection and at least 6 hours fixation is mandatory for small size biopsies. Tissue transfer to pathological labs up to 48 hours under vacuum and at +4 °C (in case of large surgical specimens) may be an alternative. Gross examination should include the description of all specimens and their integrity, the site of the tumor and the dimension of all specimens and nodules. Multiples sampling is needed, including the capsule, the solid areas, at least 1 to 2 blocks per cm of tumor for mucinous lesions, the Fallopian tube in toto, at least 3 blocks on grossly normal omentum and one block on the largest omental nodule. WHO classification should be used to classify the carcinoma (type and grade), with the use of a panel of immunohistochemical markers. High-grade ovarian carcinomas (serous and endometrioid) should be tested for BRCA mutation and in case of a detectable tumor mutation, the patient should be referred to an oncogenetic consultation.