4423
All but one of the 265 patients who were cured or improved at post - therapy returned for a long - term follow - up visit ; 243 ( 92 % ) remained well 4 to 6 weeks after therapy ; and 21 ( 8 % ) had a relapse of symptoms .
 None
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Disease, Chemical 
Text: {0} 
Answer:
 None