A Prospective Observational Study to Describe Clinical Outcomes, Treatment Patterns, Patients Characteristics Among Patients With HR+/HER2- Advanced BC Initiating Treatment With Risarg®, Piqray®, Endocrine Therapy or Chemotherapy in Routine Clinical Practice in Russia

Inclusion Criteria:

1. Age ≥ 18 years at the moment of ribociclib, alpelisib, monoET or CT treatmentinitiation.

2. Female gender.

3. Confirmed diagnosis of locally advanced/metastatic not amenable to surgery HR+/HER2-BC (progressed following prior therapy or de novo) for whom the treating physicialtook the decision to initiate treatment with ribociclib, alpelisib, monoET or CTbefore entering the study.

4. Patient who initiated treatment with ribociclib, alpelisib, monoET or CT no longerthan 4 weeks (28 days) prior to written informed consent for this study.

5. Patients with ECOG performance status ≤ 2.

6. Provision of written informed consent.

Exclusion Criteria:

1. Patients with a life expectancy of less than 3 months at the time of aBC diagnosisper the investigator's judgment.

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

3. Patients receiving active treatment for malignancies other than BC at the time ofenrollment.

4. Patients who are unable to understand the nature of the study.