Abstract
OBJECTIVE: The aim of this study was to investigate the predictive value of peripheral lymphocyte subsets for prognosis of gastric cancer (GC) patients following radical gastrectomy. METHODS: Consecutive GC patients received curative resection and examined peripheral lymphocyte subsets in Hunan Cancer Hospital were enrolled as training cohort (n=231), and those from Wuhan Union Hospital and Wuhan Tongji Hospital were included as external validation cohort (n=159). The optimal cutoff values of lymphocyte subsets for overall survival (OS) in training cohort were determined by X-tile. The independent predictive factors for OS were identified using univariate and multivariate Cox regression analyses. Furthermore, the predictive value of lymphocyte subsets were evaluated in validation cohort. RESULTS: The optimal cutoff value of T lymphocytes for OS was 0.84×10(9)/L in the training cohort. Decreased T lymphocyte (<0.84×10(9)/L) were identified as an independent predictor for unfavorable prognosis both in the training and validation cohorts (HR:2.835, 95% CI:1.580-5.087, P<0.001; HR:2.470, 95% CI:1.069-5.711, P=0.034). In the entire cohort, stratified analyses revealed that lower T lymphocyte negatively affected the oncological outcomes in patients with stage II/III disease. A synergistic influence was confirmed in those with decreased T lymphocyte and not received adjuvant chemotherapy (AC). Further analyses revealed that AC significantly prolonged OS in stage II/III patients with decreased T lymphocyte, but not in those with relatively higher T lymphocyte. CONCLUSION: Peripheral T lymphocyte numbers was a reliable predictor for OS in GC patients undergoing radical gastrectomy. Additionally, T lymphocyte might serve as an indicator for efficacy of AC in stage II/III GC patients.