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.
