The association between lymph node metastases and long-term survival in patients with epithelial ovarian cancer

Introduction
A key survival prognosis factor for patients treated for ovarian cancer is complete cytoreductive surgery where all macroscopic neoplastic implants, including enlarged metastatic lymph nodes, are removed. We presume that investigating the involvement of the lymphatic system can result in a more individualized approach to the treatment of ovarian cancer patients. The main aim of our study was to analyze the relationship between the presence, number and types of lymph node metastases and ovarian cancer patient prognosis.

Material and methods
We carried out a retrospective analysis of patients who underwent cytoreduction due to primary ovarian cancer, between 2010 and 2015. We analyzed the number of metastatic lymph nodes, the lymph node ratio defined as the ratio of the number of metastatic lymph nodes to the total number of lymph nodes removed, extracapsular involvement, and the histopathological pattern of metastases.

Results
The study group included 651 patients. Of these, 377 had lymphadenectomy, 144 presented with lymph node metastases, and 233 had no lymph node metastases. We also included a group of 274 patients who did not have lymphadenectomy. Patients with more than 4 metastatic lymph nodes and a lymph node ratio of ≥ 0.1 had significantly poorer overall survival. Extracapsular involvement had no relation to patient overall survival. Multivariant survival analysis indicated that a lymph node ratio of ≥ 0.1 was an independent predictor of poor survival.

Conclusions
The analysis of lymph node metastases in ovarian cancer patients can have predictive value for patient overall survival.