This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pediatrics
All of the following are good prognostic factors for childhood Acute Lymphoblastic Leukemia, except: 
Select and explain. 
A. Hyperdiploidy, B. Female sex, C. Pre B cell ALL, D. t (12 : 21) translocation
D: t (12 : 21) translocation
Answer: D: t (12 : 21) translocation 
Explanation: Hyperdiploidy, Female sex and pre B cell ALL are associated with good prognosis. t (12 : 21) translocation may be associated with a poor prognosis and is the single answer of exclusion. Ref: Pediatric Oncology: A Comprehensive Guide By Paul Imbach, Thomas R. Kuhne, Robe Arceci, 2004, page 23.