Randomized Controlled Clinical Study of Efficacy and Safety of Initumab Combined with Pyrrotinib and Chemotherapeutic Agents in Neoadjuvant Therapy for HER2-positive Breast Cancer with Different Treatment Cycles

Cohort A will receive initumab at initial load dose of 8mg/kg and maintenance dose of 6mg/kg intravenously on the first day of every three weeks for a total of 4 doses. Pyrrotinib 400mg orally once daily; Combined chemotherapy drugs (not limited, according to the actual clinical selection), a total of 4 cycles of administration

The initial loading dose of initumab was 8mg/kg, and the maintenance dose was 6mg/kg, which was administered intravenously on the first day of every three weeks. Pyrrotinib 400mg orally once daily; Combined chemotherapy drugs (not limited, according to the actual clinical selection), a total of 6 cycles of administration