PDCD1 and neoplasm: A significantly increased proportion of tumor infiltrating CD4+ T cells in TNBC (mean 3.16 +/- 4.16 SD; p = 0.05) and HER2+ (mean 2.03 +/- 0.99 SD; p = 0.018) patients showed a LAG-3/PD-1 co-expression compared to Luminal B patients (Fig. 4C).