3701
An episode of leukoencephalopathy is reported in a 13-year - old girl who , after standard radiotherapy for a posterior fossa medulloblastoma , received 8 treatments with a protocol containing a 4-hour infusion of 500 mg / m2 methotrexate and 12 mg intrathecal methotrexate .
 leukoencephalopathy, methotrexate; leukoencephalopathy, methotrexate
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:
 leukoencephalopathy, methotrexate; leukoencephalopathy, methotrexate