[1] St Jude Childrens Res Hosp, Dept Pathol, Memphis, TN 38105 USA
[2] St Jude Childrens Res Hosp, Dept Oncol, Memphis, TN 38105 USA
[3] Univ Nebraska Med Ctr, Dept Pathol & Microbiol, Omaha, NE USA
[4] Univ Nebraska Med Ctr, Dept Pediat, Meyer Munroe Inst, Omaha, NE USA
[5] Univ Nebraska Med Ctr, Dept Orthoped Surg, Omaha, NE USA