In subtype analysis, the prognostic effect of the IFN-γ signature was particularly pronounced in the luminal B (p = 0.007, log rank), HER2-positive (p = 0.033, log rank), and basal-like molecular subtype (p = 0.050, log rank), but not in the Luminal A breast cancer samples (Figure 5). Here, ERBB2 is linked to breast cancer.