Abstract
BACKGROUND: In recent studies, accumulating evidence has revealed a strong association between the inflammatory response and the prognosis of many tumors. There is a certain correlation of neutrophil-to-lymphocyte ratio (NLR) with the prognosis in gastric cancer (GC) patients undergoing neoadjuvant chemotherapy (NAC). However, the existing research results have remained controversial. AIM: To explore the relationship between NLR ratio and prognosis of GC patients receiving NAC. METHODS: A thorough systematic search was performed in databases such as PubMed, Embase, Web of Science, and Cochrane Library, the search is available until February 29, 2024, and studies exploring the interaction of NLR with clinical outcomes were collected. Relevant studies meeting pre-defined inclusion and exclusion criteria were carefully chosen. The outcomes included progression-free survival (PFS), relapse-free survival, disease-free survival (DFS), and overall survival (OS). The hazard ratio (HR) and its corresponding 95% confidence interval (CI) were utilized for estimation. RESULTS: Our analysis encompassed 852 patients and incorporated data from 12 cohort studies. The comprehensive analysis revealed a significant association of high NLR with reduced OS (HR = 1.76; 95%CI: 1.22-2.54, P = 0.003), relapse-free survival (HR = 3.73; 95%CI: 1.74-7.96, P = 0.0007), and PFS (HR = 2.32; 95%CI: 1.42-3.81, P = 0.0008) in patients. However, this correlation in disease-free survival was not significant. NLR demonstrated its crucial role in effectively predicting the OS of GC patients undergoing NAC at different detection times, ages, regions, and NLR thresholds. CONCLUSION: In GC patients receiving NAC, an elevated NLR is strongly associated with reduced OS and PFS. NLR has become an effective biomarker for patient prognosis evaluation, providing valuable insights for the treatment strategies of NAC in GC patients.