Based on five infiltration types (B cells, CD8 + T cells, endothelial cells, NK cells, and other cells), the dIRS system of BC was constructed in our study, and it was found that the dIRS value was significantly decreased in the BC tissues compared with the normal tissues, and the AUROC values for the training set and validation sets were all above 0.7, which indicated that the dIRS system had high accuracy for BC diagnosis. Here, CD8A is linked to breast cancer.