The prognostic impact of the neutrophil-to-lymphocyte ratio in patients with small-cell lung cancer

Background: The neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) are prognostic factors for various types of cancer. In this study, we assessed the association of NLR and PLR with the prognosis of small-cell lung cancer (SCLC) in patients who received the standard treatment. Methods: We retrospectively reviewed patients who were diagnosed with SCLC and treated with platinum-based chemotherapy between July 2006 and October 2013 in Gyeongsang National University Hospital Regional Cancer Center and Changwon Samsung Hospital. Results: In total, 187 patients were evaluated. Compared with low NLR (<4), high NLR (>= 4) at diagnosis was associated with poor performance status, advanced stage, and lower response rate. Median overall survival (OS) and progression-free survival (PFS) were worse in the high-NLR group (high vs low, 11.17 vs 9.20 months, P = 0.019 and 6.90 vs 5.49 months, P = 0.005, respectively). In contrast, PLR at diagnosis was not associated with OS or PFS (P = 0.467 and P = 0.205, respectively). In multivariate analysis, stage, lactate dehydrogenase, and NLR at diagnosis were independent prognostic factors for OS and PFS. Conclusions: NLR is easily measurable and reflects the SCLC prognosis. A future prospective study is warranted to confirm our results.