17862
RESULTS : Analysis of 24 metformin studies in subjects with T2DM showed that metformin use is associated with reduced risk for the development of cancer , in both cohort ( RR = 0 . 70 [ 95 % CI = 0 . 67 - 0 . 73 ] ) and case - control studies ( OR = 0 . 90 [ 95 % CI = 0 . 84 - 0 . 98 ] ) , but this finding was not supported by RCTs ( RR = 1 . 01 [ 95 % CI = 0 . 81 - 1 . 26 ] ) .
 metformin, metformin
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 metformin, metformin