Correlation between the neutrophil-to-lymphocyte ratio and clinicopathological parameters in epithelial ovarian cancer patients and its effect on prognosis—a retrospective cohort study

BACKGROUND: Ovarian cancer is a common malignant tumor of the female reproductive system, and its mortality rate is high. In recent years, studies have found that the neutrophil-to-lymphocyte ratio (NLR) has a correlation with the prognosis of patients with malignant tumors; however, its association with the prognosis of ovarian cancer patients has not been studied. Therefore, we designed this study to investigate the correlation between the NLR and clinicopathological parameters in patients with epithelial ovarian cancer and its effect on prognosis. METHODS: A total of 168 ovarian cancer patients (received operation in our hospital and age ≥18 years) admitted to the Pu Ren Hospital in Wuhan City and Shandong Qingdao Hospital of Integrated Traditional and Western Medicine from January 2015 to January 2017 were retrospectively included. The patients were equally divided into high NLR (n=84) and low NLR (n=84) groups according to their preoperative NLR levels (under preoperative fasting conditions, 5 mL venous blood was taken and immediately sent for examination), and the clinical characteristics and prognoses of the two groups were compared. All patients were followed up for 5 years to study the 5 years progression-free survival and 5-year mortality rate. RESULTS: Preoperative NLR levels were associated with Federation International of Gynecology and Obstetrics (FIGO) staging, ascites, and lymph node metastasis in patients with ovarian cancer (P<0.05). The area under the curve (AUC) of NLR in predicting recurrence or metastasis in ovarian cancer patients within 5 years after surgery was 0.675 [95% confidence interval (CI): 0.594–0.757, P=0.000]. Furthermore, the AUC of NLR in predicting death in ovarian cancer patients within 5 years after surgery was 0.785 (95% CI: 0.717–0.853, P=0.000). Patients in the high NLR group had a significant reduction in 5-year progression-free survival and an increased mortality rate (P=0.000). CONCLUSIONS: High NLR in patients with ovarian cancer is related to clinicopathological parameters and poor prognosis in ovarian cancer patients.