Moreover, the immune prognostic index was significant for DFS or DMFS of patients with any of the four molecular subtypes of breast cancer (P = 0.007 for HR+/HER2−; P < 0.001 for HR+ HER2+ and TNBC; P = 0.002 for HR−/HER2+) (Fig. 2b). This evidence concerns the gene ERBB2 and breast cancer.