Pre-treatment neutrophil to lymphocyte ratio as a prognostic marker to predict chemotherapeutic response and survival outcomes in metastatic advanced gastric cancer.

Background: Several studies have shown that the neutrophil to lymphocyte ratio (NLR) in peripheral blood is a prognostic factor of various cancers. However, there is limited information on the clinical and prognostic significance of NLR in patients with metastatic advanced gastric cancer (AGC). Therefore, we examined whether the NLR can be used as a prognostic marker for predicting chemotherapeutic response and survival outcomes in metastatic AGC patients who are receiving palliative chemotherapy.
Method: A total of 268 patients diagnosed with metastatic AGC were enrolled. NLR was calculated from complete blood cell count taken before the first chemotherapy treatment. Patients were divided into two groups according to the median value of NLR: a high NLR group and a low NLR group.
Result: The median follow-up period was 340 days (range 72-1796 days) and median NLR was 3.06 (range 0.18-18.16). The high NLR group (NLR >3.0) contained 138 patients and the low NLR group (NLR ≤3.0) contained 130 patients. Low NLR group patients had a significantly higher chemotherapeutic disease control rate (90.0 % vs. 80.4; P = 0.028), and longer progression-free survival (PFS) and overall survival (OS) than the high NLR group patients (186 vs. 146 days; P = 0.001; 414 vs. 280 days; P < 0.001, respectively). In multivariate analysis, NLR showed a significant association with PFS (HR 1.478; 95 % CI 1.154-1.892; P = 0.002) and OS (HR 1.569; 95 % CI 1.227-2.006; P < 0.001).
Conclusion: Pretreatment NLR is a useful prognostic marker in patients with metastatic AGC who are undergoing palliative chemotherapy.