Clinico-pathologic characteristics and prognostic factors of ovarian carcinoma with different histologic subtypes - A benchmark analysis of 482 cases.

ABSTRACT

PURPOSE: Ovarian carcinomas (OCX) have traditionally been thought to arise from the ovarian surface epithelium. However, recent (immuno-) histopathological and molecular analyses suggest that OCX consist of morphological subtypes with different epidemiologic features and a varying prognosis. METHODS: The data of 482 OCX from the Clinical Cancer Registry of Leipzig who were surgically treated between 2000 and 2019 and were evaluated regarding incidence, clinico-pathologic characteristics and prognostic factors. Cases were separated into high-grade and non-high-grade serous tumors. Both groups were analyzed regarding the tumor stage, lymph node involvement, site of origin and prognosis. RESULTS: The overall incidence for OCX was 17.9. The most common histological subtype was high-grade serous OCX (57.9%; 279/482). Patients with high-grade were significantly older than those with a non-high-grade serous OCX (63.9 versus 58.5 years; p < 0.001), more frequently diagnosed at an advanced stage >pT3 (78.5% (219/279) versus 42.8% (87/203); p < 0.001) and showed a 2.4-fold higher frequency of lymph node metastases (53.4% vs. 21.2%; p < 0.02) with a 4.6-fold higher rate of > 1 cm metastatic deposits (pN1b) within the lymph nodes (14.8% vs. 4.6%; p < 0.02). Irrespective of tumor stage and morphological subtype, the 1- and 5-year overall survival (OAS) was 72.9% and 40.8%, respectively. Patients with high-grade serous OCX showed a shorter 5-year OAS compared to non-high-grade serous OCX (34.1% vs. 57.0%; p 0.001). This association was reproducible in patients with an advanced tumor stage irrespective of the histopathologic tumor type serous OCX (pT3 32.4% vs. pT1 75.1%; p 0.001) as well as within high-grade (pT3 28.7% vs. pT1 55.5%; p = 0.003) and non-high-grade serous OCX (pT3 43.0% vs. 80.0%; p 0.001). There were no differences in OAS depending on the site of origin (fallopian tube, ovary, peritoneum) within the two histologic subgroups. CONCLUSION: OCX cases from a single institution with uniform surgical treatment and a standardized histopathological workup were evaluated. The poor prognostic outcome of patients with high-grade serous compared non-high-grade serous OCX as well as an advanced stage of the disease was confirmed. This study demonstrates for the first time that the histopathological distinction into high-grade serous and non-high-grade serous tumors may be much more prognostically relevant than the site of origin.