19970
PET imaging with [ ( 18 ) F ] fluoro - 2 - deoxy - d - glucose ( [ ( 18 ) F ] FDG ) has been used to image alterations in glucose metabolism in brain or cancer tissue in the field of clinical diagnosis but not in the field of toxicology .
 [ ( 18 ) F ] fluoro - 2 - deoxy - d - glucose, [ ( 18 ) F ] FDG, glucose
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 [ ( 18 ) F ] fluoro - 2 - deoxy - d - glucose, [ ( 18 ) F ] FDG, glucose