Overview
This study is a post-marketing, observational, multicenter, prospective study. It will investigate the the safety and effectiveness of T-DM1 in the Chinese population in real-world clinical practice.
Eligibility
Inclusion Criteria:
- Diagnosed with HER2-positive, unresectable locally advanced or metastatic breast cancer before the start of T-DM1 treatment
- Had prior treatment for breast cancer which must contain a taxane and trastuzumab
- Get the treatment of T-DM1 for the first time after diagnosis of breast cancer
Exclusion Criteria:
- Patients not receiving treatment for HER2-positive breast cancer with T-DM1 according to standard of care and in line with the current summary of product characteristics (SPC)/local labeling
- Has been previously treated with T-DM1 before current clinical visit
- Currently participating in any clinical trials
- Previously participated in any clinical trials investigating anti-HER2 drug within 1 year of the initiation of T-DM1