This is a pilot, prospective, interventional, monocentric study designed to evaluate, in a real-life situation, adherence to tamoxifen treatment as a function of the taking of alternative and complementary therapies in patients with localized hormone-dependent breast cancer.

200 patients will be included in the study.

Each patient will be followed for one day.

Inclusion Criteria:

1. Age ≥ 18 years at entry into the study.
2. Patient treated for hormone-dependent localized breast cancer requiring adjuvant Hormonal Therapy (HT) with tamoxifen.
3. Patients treated with tamoxifen for a maximum of 1 to 3 years.
4. Patient affiliated with a Social Security system in France.
5. Patients who signed informed consent prior to inclusion in the study and prior to any specific study procedures.

Exclusion Criteria:

1. Pregnant or breastfeeding women.
2. Any psychological, family, geographical or sociological condition that does not allow the medical follow-up and/or the procedures foreseen in the study protocol to be respected.
3. Patient who has forfeited his/her freedom by administrative or legal award or who is under legal protection (curatorship and guardianship, protection of justice).