Frequency and distribution of lymph node metastases in epithelial ovarian cancer.

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 paraaortic 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.