In particular, patients who achieve pathological complete response (pCR) following NACT have more favourable outcomes when compared with those with residual disease, regardless of specific biological tumour type i.e., triple-negative breast cancer (TNBC), vs. human epidermal growth factor receptor 2 positive (HER2+) BC vs. hormone receptor positive and HER2 negative (HR+/HER2−) BC.3 This evidence concerns the gene HR and breast cancer.