Statement: A patient with stage 2B , pathologically confirmed PR positive breast cancer is elgible for both the primary trial and the secondary trial.
Primary_evidence: Inclusion Criteria:   Patient evaluated and treated at INCAN   Patients must provide informed consent   Patient must be  18 years of age.   Life expectancy  6 months   Clinical locally advance breast cancer (Stage IIB or III)   Pathologically confirmed diagnosis of estrogen receptor (ER)-positive or progesterone receptor (PR)-positive breast cancer with ER or PR Allred Score > 4   Patient must have an ECOG Performance Status of 0-2   Patients must be able to swallow and retain oral medication Exclusion Criteria:   Patient must not have received any prior chemotherapy, radiation therapy, or biologic therapy for invasive breast cancer within the past five years   Patient must not be pregnant or nursing   Patient must not have had any prior malignancy except for adequately treated basal cell (or squamous cell) skin cancer, in situ cervical cancer or other cancer for which the patient has been disease-free for five years.   Women of childbearing age unable or unwilling to use contraception
Secondary_evidence: Inclusion Criteria:   Premenopausal, estrogen receptor positive women, aged 20 years and over, with operable and measurable breast cancer who have provided written informed consent Exclusion Criteria:   Medical history of chemotherapy or endocrine therapy for breast cancer, or with treatment history of radiotherapy. Unwillingness to stop taking any drug known to affect sex hormone status (including hormone replacement therapy (HRT).