2457
We report here a retrospective study of 123 children ( median age , 6 . 5 years ) receiving high - dose busulfan in combined chemotherapy before bone marrow transplantation for malignant solid tumors , brain tumors excluded .
 Chemical: busulfan; Disease: tumors; Disease: brain tumors
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:
 Chemical: busulfan; Disease: tumors; Disease: brain tumors