NAC is mainly utilized to preoperatively downgrade the size of the tumor, control disease, obtain prognostic information, and possibly improve survival.[3] According to the National Comprehensive Cancer Network (NCCN) guideline, NAC has been accepted as standard care for preoperative patients with stage IIA-IIIC disease, especially those with human epidermal growth factor receptor 2 (HER2)-positive breast cancer and triple-negative breast cancer (TNBC).[4] Pathological complete response (pCR), as a key indicator, is correlated with the efficacy of NAC and patient outcomes. The gene discussed is ERBB2; the disease is neoplasm.