A study to investigate the effectiveness of trastuzumab emtansine compared with trastuzumab in a type of breast cancer (called HER2 positive breast cancer) for patients who still have signs of tumours after receiving previous treatment and undergoing surgery (KATHERINE)

A Study of Trastuzumab Emtansine Versus Trastuzumab as Adjuvant Therapy in Patients With HER2-Positive Breast Cancer Who Have Residual Tumor in the Breast or Axillary Lymph Nodes Following Preoperative Therapy (KATHERINE)