178332
While this study was conducted to establish dose tolerance , six of the 15 treated patients were still alive 2 years later , although their life expectancy at the beginning of the trial was six months or less .
 None
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
 Entities:  
Answer:
 None