Preoperative lymphocyte count is a favorable prognostic factor of disease-free survival in non-small-cell lung cancer

Recently, the prognostic value of cancer-related inflammatory response has been revealed. Previous studies showed that peripheral neutrophils and lymphocytes had significant impact on the prognosis of advanced and early-node-negative non-small-cell lung cancer (NSCLC). The purpose of this study was to investigate the prognostic value of preoperative lymphocyte and neutrophil counts in patients with NSCLC who underwent lobectomy and lymph node dissection and adjuvant chemotherapy. Retrospective analyses were performed to examine the impact of preoperative peripheral lymphocyte and neutrophil counts on disease-free survival (DFS) and overall survival (OS) and to analyze the relationships of these factors to clinicopathological factors. A total of 142 patients with NSCLC were evaluated of which 57 (40.1 %) patients had local recurrence or metastasis. Multivariate analyses revealed that peripheral lymphocyte count was an independent favorable prognostic factor of DFS (hazard ratio 0.548; 95 % confidence interval 0.351-0.857; P = 0.008) but not OS (P = 0.164). The maximum logrank statistical value was 9.504 (P = 0.002) when the cutoff value of lymphocyte was 1,800 mm(-3). The median DFS was 318.0 days (95 % confidence interval 226.0-410.0) for lymphocyte <= 1,800 mm(-3) group and 669.0 days (95 % confidence interval 0.0-1,431.0) for lymphocyte[1,800 mm(-3) group. Low lymphocyte count was related with lymphatic invasion (P = 0.012) and recurrence of NSCLC (P = 0.022). Peripheral neutrophil count had no impact on DFS or OS when analysis included all the 142 patients. Preoperative peripheral lymphocyte count, which is related with lymphatic invasion, is an independent favorable prognostic factor of DFS in patients with NSCLC who underwent lobectomy and lymph node dissection and adjuvant chemotherapy.