This nationwide, retrospective study was performed as part of the Hungarian HUN- CANCER EPI Multiple Cancer Epidemiology program to provide a deeper analysis into breast cancer subtypes than epidemiology results our team already published (16) and to examine breast cancer incidence and survival in Hungary between 2011 and 2020, focusing on major BC subtypes based on HR and HER2 status. The gene discussed is ERBB2; the disease is breast cancer.