PROACTIVE randomized study to evaluate the impact of a multidimensional geriatric intervention on treatment compliance, measured regularly by blood dosing of drug metabolites.

Patients in the intervention group will be proposed:

• A regular geriatric follow up including an attentive screening of joint symptoms and functionality,
• An adapted treatment of join pain,
• Weekly sessions of adapted physical activity (Taï Chi),
• And a systematic correction of vitamin D deficits.

Inclusion Criteria:

• Age ≥ 70 years old
• Non metastatic breast cancer, with or without node metastases
• Hormone Receptor (HR) positive breast cancer patients
• Women with breast adenocarcinoma, confirmed by a pathologist and who underwent surgery or radiotherapy
• Introduce an hormonal therapy during 5 years
• Life expectancy > 6 months (at the discretion of the investigator)
• Covered by a Health System where applicable, and/or in compliance with the recommendations of the national laws in force relating to biomedical research
• Patient must be available for follow-up
• Having given written informed consent prior to any procedure related to the study

Exclusion Criteria:

• No other primary malignant tumor < 5-years old except cured in situ cancer of the cervix, in situ urothelial cancer, or basocellular cancer
• Patient with an experimental treatment in the 30 days prior to the enrollment
• Evidence of metastatic disease
• Not under any administrative or legal supervision