Intratumoral CXCR5CD8T associates with favorable clinical outcomes and immunogenic contexture in gastric cancer.

Studies that examined an association between CD8T and prognosis in gastric cancer are inconsistent, and a distinct population of CXCR5CD8T associated with better overall survival has been reported among various malignancies. Here, we show that the abundance of intratumoral CXCR5CD8T cells is associated with better overall survival in patients with gastric cancer. Patients with TNM II + III gastric cancer with higher intratumoral CXCR5CD8T cell infiltration are more likely to benefit from adjuvant chemotherapy. Microsatellite-unstable and Epstein-Barr virus positive tumors are enriched with CXCR5CD8T cells. Gastric cancer infiltrating CXCR5CD8T cells represent a specific subtype of stem-like CD8T with effector memory feature. Identification of the clinical significance and phenotype of gastric cancer infiltrating CXCR5CD8T provides a roadmap for patient stratification and trials of targeted therapies.