While patients with HR-positive breast cancer are believed to have a lower chance of pCR to NAC compared to those with HER2-positive and triple-negative subtypes [30, 31], the current findings suggest that 18F-FDG PET/CT may allow the identification of good responders to chemotherapy among patients with HR positive breast cancer; further studies for its use in breast cancer should be considered. This evidence concerns the gene ERBB2 and breast cancer.