29197
This article summarizes the milestones in the development of trastuzumab emtansine leading to this first approval for the treatment of patients with HER2 - positive , metastatic breast cancer who previously received trastuzumab and a taxane , separately or in combination .
 taxane
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 taxane