Inclusion Criteria:  Women ≥ 18 years Early stage breast cancer, ER and/or PR positive with HER2 negative breast cancer.  Exclusion Criteria:  More than one operable primary breast tumor; Multifocal or multicentric tumors; 4 or more lymph node involvement; Metastatic breast cancer; Previous history of breast cancer; Invasive tumor <2 mm ; Performance status > 2 and / or other clinical factors that would make the patient a non-viable candidate for adjuvant chemotherapy; Previous hormonal or chemotherapy treatment; Current medical condition that would interfere with their ability to consent (psychiatric illness, for example)