This study is to evaluate the efficacy of tucidinostat combined with exemestane as neoadjuvant strategy in estrogen receptor-positive early breast cancer patients and explore the genetic model which can predict neoadjuvant endocrine therapeutic results.

This study is to evaluate the efficacy of tucidinostat combined with exemestane as neoadjuvant strategy in estrogen receptor-positive early breast cancer patients.This study will recruit 30 patients. The 30 patients will receive 25 mg exemestane QD for 26 weeks. Tucidinostat will be prescribed 30 mg BIW from week 3 to week 26. During neoadjuvant treatment biopsy, CEUS and MRI will be perfomed according to protocol to evaluate the therapeutic results. Genetic testing will also be performed before and after neoadjuvant treatment to explore the predictive value. MRI evaluated ORR is primary end point. CEUS evaluated ORR, pCR, AE and RCB are secondary end point.

Inclusion Criteria:

1. Written informed consent must be signed；
2. Eastern Cooperative Oncology Group Performance Status: 0~1;
3. Histological confirmation of estrogen receptor (ER) positive and HER 2 negative invasive breast cancer;
4. Age ≥18 years old；
5. No distant metastatic disease；
6. The disease condition is stage II or stage III;
7. Laboratory exam criteria for enrollment: HGB≥10g/dl, WBC≥4,000/mm3, PLT≥100,000/mm3, GOT, GPT, ALP≤2 times ULN, TBIL, CCr≤1.5 times ULN.

Exclusion Criteria:

1. Patients who are pregnant or lactating at the time of randomization or refuse to contraception.
2. Patients who received organ transplantation (include bone marrow autologous transplantation and stem cell transplantation).
3. Patients who have other malignant diseases within 5 years, except for cured skin basal cell carcinoma, flat cell carcinoma or cervical carcinoma in situ
4. Patients with psychiatric disorder, peripheral or central nerve system disease or any disorder, which compromises ability to give informed consent or participate in this study.
5. Patients with sever hepatic, renal,cardiovascular, respiratory, digestive diseases or uncontrolled diabetes.
6. Patients who had myocardial infarction in the past 12 months.
7. Patients who participate in other clinical trail.
8. Patients who allergy to goserelin, leuprorelin, tucidinostat or aromatase inhibitor.