Frequency and Distribution of Lymph Node Metastases in Epithelial Ovarian Cancer Significance of Serous Histology

Background: The aim of this retrospective study was to evaluate the incidence and distribution of nodal metastases in relation to the serous versus nonserous histological subtypes of epithelial ovarian cancer. Methods: Patients were treated primarily with upfront surgery, including pelvic and para-aortic systematic lymphadenectomy, up to the level of the left renal vein, before any kind of chemotherapy administration. Patients were classified according the tumor histology into 2 groups: serous (including the cases of mixed histology with a serous component) and nonserous group. Results: A total of 173 patients fulfilled the inclusion criteria; 76 and 97 patients had serous and nonserous ovarian carcinoma, respectively. Positive lymph nodes were found in 59.3% (45/76) and 14.4% (14/97) of patients in the serous and nonserous histology groups, respectively. There was no difference in positive node distribution in 3 regions (pelvic and para-aortic regions, below and above the inferior mesenteric artery) between these 2 groups. Early spread including 1 or 2 positive lymph nodes was predominantly found in the para-aortic region in both groups, serous and nonserous, whereas distribution of positive nodes in patients with 3 or more lymph nodes shows equal presence in pelvic and para-aortic regions. Conclusions: Serous ovarian carcinomas are much more prone to metastasize to lymph nodes than nonserous histological types. However, the pattern of lymph node distribution did not differ between these 2 groups and was similar in the pelvic and para-aortic regions.