ERBB2 and triple-negative breast carcinoma: Considering the discrepancy between HR-positive and HR-negative breast cancers in terms of both molecular nature and clinical management, we stratified patients by HR status to characterize HER2-low breast cancers among luminal and triple-negative breast cancers (TNBCs) separately, and no significant differences were found regardless of HR status in terms of clinicopathological characteristics (Table 1).