Included patients will be followed until the end of study, death or lost to follow-up even if ribociclib and ET are discontinued. The end of the study is defined as 3 years after the first visit of the last patient included (Last Patient First Visit [LPFV]). The total duration of the study will be 4 years and half (18 months of inclusion + 3 years of follow-up). Thus, a patient included at the beginning of the inclusion period will be followed for 4 years and half and a patient included at the end of the inclusion period will be followed for at least 3 years.
This study is a national, multicenter, prospective, non-interventional study in women with HR+/HER2- locally advanced or metastatic breast cancer (BC), for which a prior clinical decision to initiate ribociclib + endocrine therapy (ET) treatment according to the marketing authorization has been taken and was taken independent and prior to study participation decision.