[1] Univ Pittsburgh, Dept Radiol, Pittsburgh, PA 15260 USA
[2] Univ Pittsburgh, Med Ctr, Hillman Canc Ctr, Pittsburgh, PA USA
[3] Childrens Hosp Michigan, Dept Hematol Oncol, Detroit, MI 48201 USA
[4] Univ Texas MD Anderson Canc Ctr, Dept Leukemia, Houston, TX 77030 USA
[5] Mayo Clin, Dept Pediat Hematol Oncol, Rochester, MN USA