ERBB2 and breast cancer: This includes the era of cancer diagnostics, which has recognized BC as a diverse disease and routinely subcategorized these cancers into four genetically distinct, integral subgroups - luminal A breast cancer (LABC), luminal B breast cancer (LBBC), human epidermal growth factor receptor-2 enriched breast cancer (HER2+) and triple-negative breast cancer (TNBC).