Association between density of tumor-infiltrating lymphocytes and prognoses of patients with gastric cancer

摘要

Introduction: Tumor-infiltrating lymphocytes (TILs) have been shown to be of prognostic significance in patients with gastric cancer . This study aims to investigate the association between density of TILs and prognoses of patients with gastric cancer . Methods: The relative studies of tumor-infiltrating lymphocytes in tumor tissue from patients with gastric cancer were systematically searched from PubMed and Embase until October 31, 2017. The pooled hazard ratios (HRs) and their 95% confidence intervals (95%CI) for overall survival (OS) were estimated. Results: Twenty-nine studies involving 4,942 patients were included into analyses. Subset of TILs included CD8^{+, CD3+, CD4+, and FOXP3+ T cell density. Results from meta-analyses revealed that high density of intratumoral CD8+ T cells (HR = 0.77, 95% CI 0.63–0.95) and CD3+ (HR = 0.62, 95% CI 0.49–0.77) were associated with significantly higher OS than those with low density in patients with gastric cancer . Moreover, a larger number of general TILs density also suggested a favorable prognosis (HR 0.75, 95% CI 0.67–0.84). However, patients with high density of intratumoral FOXP3+ T or CD4+ T cells were not statistically associated with higher or lower OS than those with low density (HR 1.41, 95% CI 0.97–2.05; HR = 0.86, 95% CI 0.47–1.57). Sample size and follow-up period seemed to influence study outcomes. Conclusion: The present study revealed that high density of intratumoral CD8+ and CD3+ T cells were associated with better OS in patients with gastric cancer .}