Inclusion Criteria:

1. Patients > 18 years old.

2. Pre- or post- menopausal women with breast adenocarcinoma, confirmed by a pathologist
and who underwent surgery, with a maximum of 4 weeks between surgery and the 2nd
therapeutic decision with Oncotype DX.

3. HR positive (at least ER+) breast cancer patients (defined by a threshold of 10% of
the cells IHC + without N- or pN1(mi), Her2 - (IHC0, 1, 2+ or FISH -)

4. Patients must be eligible to receive adjuvant chemotherapy as defined by a good
Karnofsky index, no hematological, cardiological or hepatic contraindications nor any
impeding comorbidity.

5. Patients must have given a written informed consent.

Exclusion Criteria:

1. T3 or T4, HR-, N+ (except pN1 (mi) (sn), Her2+ (IHC 3+ or Fish+) patients.

2. Metastatic patients.

3. Patients who cannot give an informed consent.

4. Patients who cannot receive chemotherapy.

5. Patient who participated in another clinical trial and is still in the exclusion
period of any other trial.

6. Mentally disabled patient who has no legal responsibility for herself.