Neutrophil‑to‑lymphocyte ratio before each chemotherapy line predicts clinical outcomes in patients with unresectable gastric cancer

The neutrophil-to-lymphocyte ratio (NLR) is a well-known prognostic biomarker for patients with gastric cancer (GC). However, for patients with GC treated with palliative chemotherapy, the predictive values of NLR remain obscure. Therefore, the present study evaluated the clinical impact of NLR in patients with GC treated with a series of chemotherapies. The present study retrospectively evaluated 83 patients with unresectable GC who received a series of chemotherapies. NLR in the blood was calculated before each chemotherapy initiation (before 1st-, 2nd- and 3rd-line treatment). Of the 83 patients enrolled, 56 patients (67%) received 2nd-line chemotherapy and 34 patients (41%) received 3rd-line chemotherapy. NLR at 1st-line ranged from 0.72 to 48.9 (median NLR, 3.00). Therefore, the median NLR of 3.00 was used as a definite cut-off value throughout the present study. All patients were dichotomized into NLR-high (>3.00) and NLR-low group (<3.00) by NLR evaluated before each line of chemotherapy. The median overall survival (OS) time of the low-NLR group was better than that of the high-NLR group from 1st-line to 3rd-line treatment (1st-line: 18.1 vs. 8.0 months, P=0.06; 2nd-line: 10.7 vs. 4.5 months, P=0.0001; 3rd-line: 8.7 vs. 4.7 months, P=0.003). Of the 24 patients treated with 3rd-line nivolumab, patients with low NLR exhibited better OS than those with high NLR (8.3 months in low-NLR and 6.6 months in high-NLR, P=0.06). In conclusion, NLR should be performed before each chemotherapy line in the clinical setting and may predict outcomes in patients with unresectable GC, including those treated with nivolumab.