Neoadjuvant Combined Endocrine and HER2 Target Therapy in Postmenopausal Women With ER and Her2 Positive Breast Cancer

Inclusion Criteria: * Written informed consent * Female patients * Histologically confirmed invasive breast cancer * Primary tumor greater than 2cm diameter, measured by sonography * N0-3 (any N if resectable) and no evidence of distant metastasis (M) (isolated supraclavicular node involvement allowed) * ER positive (intermediate and strong positive) * HER2 positive (IHC3+ or FISH positive in case of IHC 2+) * No evidence of metastasis (M0) * No prior hormonal, chemotherapy or radiotherapy is allowed * No breast operation other than biopsy to make diagnosis is allowed * Postmenopausal women with ECOG Performance Status of 0 or 1 * Postmenopausal, as defined by any of the following: * At least 55 years of age * Under 55 years of age and amenorrheic for at least 12 months OR follicle-stimulating hormone (FSH) values ≥ 30 IU/L and estradiol levels ≤ 20 IU/L * Prior bilateral oophorectomy or prior radiation castration with amenorrhea for at least 6 months * Adequate hematopoietic, renal, hepatic function: Exclusion Criteria: * Patients who received hormonal, chemotherapy or radiotherapy for breast cancer * Patients who underwent surgery for breast cancer * Patients with bilateral invasive breast cancer * Patients with inflammatory breast cancer (T4d) * Patients without primary tumor (T0) Inability to perform \[18F\]FES PET imaging due to physical inability, claustrophobia, or other mental illness. * ER poor disease as defined locally (e.g: Allred score 1-3, H-score\<100) * Patients who have history of cancer other than in situ uterine cervix cancer or non-melanotic skin cancer * Chronic daily treatment with aspirin (\>325mg/day) or clopidogrel (\>75mg/day) * Chronic daily treatment with corticosteroids (dose of \>10mg /day ethylprednisolone equivalent) * Clinically significant cardiovascular disease: CVA/stroke (\<6month prior to enroll), MI (\<6month prior to enroll), unstable angina, NYHA Grade II or greater congestive heart failure, or serious cardiac arrhythmia requiring medication. * Hormone replacement therapy within 4 weeks of starting treatment * Known hypersensitivity to any of the study drugs including ditosylate monohydrate salt * Pregnant or nursing mother (if applicable)