Palbociclib + Letrozole Versus Epirubicin + Cyclophosphamide and Sequential Docetaxel as Neoadjuvant Chemotherapy

Endocrine group will receive palbociclib combined with letrozole: palbociclib (Pfizer Manufacturing Deutschland GmbH, Freiburg, Germany; license number: H20180040) 125 mg/d, every 28 days as a cycle (medication for 3 consecutive weeks and withdrawal for 1 week); letrozole (Novartis Pharma Schweiz AG, Stein, Switzerland; license number: H20140149) 2.5 mg/d, for 6 consecutive months.

Chemotherapy group will receive epirubicin combined with cyclophosphamide and sequential docetaxel: epirubicin (Pfizer Wuxi Pharmaceutical Plant, Wuxi, China; license number: GYZZ H20000496), 90 mg/m2, intravenously, for 120 minutes, once every four weeks, totally four times; cyclophosphamide (Baxter Oncology GmbH, Halle, Germany; license number: H20160468), 600 mg/m2, once every four weeks, totally four times; sequential docetaxel (Sanofi-aventis Deutschland GmbH, Frankfurt am Main, Germany; license number: GYZZ J20150083) 75 mg/m2, intravenously, for 120 minutes, once every four weeks, totally four times.