Abstract
Studies that examined an association between CD8(+)T and prognosis in gastric cancer are inconsistent, and a distinct population of CXCR5(+)CD8(+)T associated with better overall survival has been reported among various malignancies. Here, we show that the abundance of intratumoral CXCR5(+)CD8(+)T cells is associated with better overall survival in patients with gastric cancer. Patients with TNM II + III gastric cancer with higher intratumoral CXCR5(+)CD8(+)T cell infiltration are more likely to benefit from adjuvant chemotherapy. Microsatellite-unstable and Epstein-Barr virus positive tumors are enriched with CXCR5(+)CD8(+)T cells. Gastric cancer infiltrating CXCR5(+)CD8(+)T cells represent a specific subtype of stem-like CD8(+)T with effector memory feature. Identification of the clinical significance and phenotype of gastric cancer infiltrating CXCR5(+)CD8(+)T provides a roadmap for patient stratification and trials of targeted therapies.