Prognostic significance of peripheral blood-derived neutrophil/lymphocyte ratio in patients with digestive cancer

Accumulating studies reported the clinical value of derived neutrophil/lymphocyte ratio (dNLR) regarding the prediction of survival outcomes in digestive cancers, however, the prognostic significances of dNLR in these cancers were inconsistent. This study was carried out to clarify the relationship between circulating dNLR and prognosis in gastrointestinal (GI) cancers. Eligible publications were collected and extracted by searching Pubmed, Embase, Web of Science, and Google Scholar up to November 21, 2018. The prognostic impact of dNLR in subjects with GI cancers was assessed with the overall hazard ratios (HRs). A total of 26 studies with up to 13,945 participants were recruited. Our findings showed that peripheral blood dNLR before treatment could be a useful prognostic predictor in digestive cancers, an elevated dNLR indicated a shorter overall survival (OS) in GI tumors (HR, 1.44; 95% confidence interval [CI], 1.36-1.51). Furthermore, its significant prognostic value for OS was also confirmed in subgroup analyses stratified by disease type, publication year, type of research, detection method, geographic location, cut-off value, treatment, analysis type, follow-up time and disease stage. In addition, high dNLR was significantly associated with worse cancer-specific survival (HR, 1.25; 95% CI, 1.04-1.47) and inferior event-free survival (HR, 1.22; 95% CI, 1.11-1.33) in patients with digestive cancers. Our study showed elevated peripheral blood dNLR may indicate unfavorable outcomes in digestive cancer.