ERBB2 and breast cancer: We observed that in the HRD-H subgroup, 45% of the patients were classified as basal-like breast cancers, 11% as HER2-enriched, 15% as Luminal A, and 26% as Luminal B. In contrast, only 7% of the cases in the HRD-L subgroup were basal-like, 7% were HER2-enriched, 64% were Luminal A, and 18% were Luminal B (Fig. 3A) [52].