9536
Musculoskeletal complaints were the presenting symptoms in four of 44 children ( 9 % ) treated for relapsed Wilms ' tumors with ifosfamide , a derivative of cyclophosphamide .
 Musculoskeletal complaints, cyclophosphamide; Musculoskeletal complaints, ifosfamide
Please list all entity pairs containing a certain relationship in the given options.Output format is "word1, word2; word3, word4". 
Option: adverse effect 
Text: {0} 
Answer:
 Musculoskeletal complaints, cyclophosphamide; Musculoskeletal complaints, ifosfamide