2429
The use of an appropriate solution of methylene blue ( 0 . 2 % in 0 . 9 M NaCl for 15 min ) permits the staining of premalignant areas and CIS , and their early diagnosis .
 None
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: GENE 
Text: {0} 
Answer:
 None