PDCD1 and breast carcinoma: Relevant data from a large cohort study strongly supported TIM-3 as a prospective target for BC immunotherapy based on their finding that 28% basal-like breast cancers and 18% non-basal TNBC possessed TIM-3 expression in intra-epithelial TILs (iTILs), respectively, and TIM-3 + iTILs significantly correlated with PD-1, LAG-3, and PD-L1 expression in BC (48).