Prognostic value of neutrophil-to-lymphocyte ratio in early-stage ovarian clear-cell carcinoma

Objectives: There is increasing evidence that systemic inflammatory response (SIR) markers are prognostic factors for various types of cancers. This is the first study to evaluate the usefulness of SIR markers for the prognosis of early-stage ovarian clear-cell carcinoma (OCCC). Methods: We retrospectively investigated 83 patients diagnosed with stage I-II OCCC who underwent surgery between 2005 and 2017. Initially, receiver operating characteristic curve analysis for overall survival (OS) was used to determine optimal cut-off values for neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR). Patients were stratified into 2 groups by the cut-off values (NLR=3.26, PLR=160). Univariate and multivariate analyses were performed to elucidate the significance of SIR markers as prognostic factors. Results: In the median follow-up period of 64.1 months, 16 patients experienced recurrence, and nine patients died. The Kaplan-Meier curve showed that OS of the NLR-low group was significantly longer than the NLR-high group (p=0.021). There was no significant difference in progression-free survival between the 2 groups (p=0.668), but the post-recurrence survival of the NLR-low group was significantly longer than the NLR-high group (p=0.019). Furthermore, multivariate analysis showed that increase in NLR is a significant independent prognostic factor for poor prognosis (hazard ratio=7.437, p=0.017). There was no significant difference between PLR-low and PLR-high group. Conclusion: Results suggest that NLR can be a significant independent prognostic factor for early-stage OCCC.