CD127− CD39hi Trm could also be detected in lymph nodes collected at the time of primary surgery (Supplementary Fig. 2b) and preferentially infiltrated metastatic, tumor-draining lymph nodes compared to tumor-free lymph nodes (Fig. 2d), suggesting that CD39 identifies putative tumor-reactive CD8+ Trm cells also in BC similar to other types of human tumors15,16. This evidence concerns the gene CD8A and breast cancer.