TIGIT and breast cancer: A recently published meta-analysis demonstrated the prognostic value of tumor-infiltrating TIGIT + CD8+ T-cells in patients with solid cancers in which its high expression is associated with a worst OS and relapse free survival (RFS) [105], albeit Fang et al. reported a favorable outcome with longer OS and RFS due to the correlation between CTLA-4 and TIGIT in breast cancer patients [106].