A Prospective Non-interventional Study to Evaluate Clinical Outcomes of Ribociclib Combined With Endocrine Therapy in Elderly Patients With HR+HER2 - Advanced Breast Cancer in Routine Clinical Practice in Russian Federation

Inclusion Criteria:

1. Age ≥ 65 years at the moment of ribociclib+ET initiation

2. Female/Male gender

3. Confirmed diagnosis of locally advanced/metastatic not eligible for curative surgeryHR+HER2- BC for whom the treating physician took the decision to initiate treatmentwith ribociclib+IA/FUL in the first or in the second line of the treatment

4. Patient who initiated treatment with ribociclib+IA/FUL no longer than 4 weeks (28days) prior to written informed consent for this study

5. Provision of written informed consent.

Exclusion Criteria:

1. Patients with a life expectancy of less than 3 months per the investigator'sjudgment

2. Patients participating in any interventional clinical trial that includesinvestigational or marketed products at the time of enrollment. (Patientsparticipating in other investigator initiated research or NIS can be included aslong as their standard of care is not altered by the study)

3. Patients on active treatment for malignancies other than aBC within 3 years beforeBC diagnosis

4. Patients with active cardiac disease, or history of cardiac dysfunction, includingprolonged QT interval corrected using Fridericia's formula (QTcF > 450 msec).