Data source
We conducted an independent review of citations from PubMed, EMBASE and Cochrane library databases between January 1 1990 and October 31 2019. Keywords were trastuzumab, lapatinib, pertuzumab, T-DM1, neratinib, pyrotinib, anti-HER2 agents, HER2 blockade, breast cancer, breast carcinoma, clinical trial and randomized. The search was limited to prospective randomized clinical trials published in English. The search strategy also used text terms such as anti-HER2 agents and HER-2 blockade to identify relevant information. We also performed independent searches using EMBASE and Cochrane library databases between January 1 1990 and October 31 2019, to identify relevant trials. Additionally, we searched abstracts containing the term “trastuzumab”, “lapatinib”, “T-DM1”, “pertuzumab”,”anti-HER2 agents” that were presented at the American Society of Clinical Oncology (ASCO) and the European Society of Medical Oncology (ESMO) annual meetings from 2004 to 2013 to identify relevant studies. Each trials was carefully reviewed and in cases of duplicate publication only the most complete, recent and updated report of the clinical trial was included for analysis.