Judged from CID plot (Fig. 1) of HR+/HER2+ subtype, the CID of breast cancer specific mortality (BCSM) of <40 years group had a similar tendency with CID of other causes of deaths of >50 years group, indicating that the worse OS of HR+/HER2+ in older patients might be a result of other causes of deaths. The gene discussed is ERBB2; the disease is breast cancer.