[1] Mem Sloan Kettering Canc Ctr, Dept Pediat, New York, NY USA
[2] Univ Bern, Bern Univ Hosp, Dept Pediat, Div Pediat Hematol & Oncol,Inselspital, Bern, Switzerland
[3] Washington Univ, Div Pediat Hematol Oncol, Sch Med, St Louis, MO USA
[4] UCL, Dev Biol & Canc Res & Teaching Dept, Great Ormond St Inst Child Hlth, London, England
[5] Rigshospitalet, Dept Pediat Oncol & Hematol, Copenhagen, Denmark
[6] Inst Nacl Canc, Res Ctr, Pediat Hematol & Oncol Program, Rio De Janeiro, Brazil
[7] Princess Maxima Ctr Pediat Oncol, Utrecht, Netherlands
[8] Unidad Nacl Oncol Pediat, Guatemala City, Guatemala
[9] Baylor Coll Med, Texas Childrens Canc Ctr, Dept Pediat, Div Hematol Oncol, Houston, TX USA
[10] Childrens Canc Therapy Dev Inst, Dept Med Oncol & Hematol, Pediat Oncol Unit, Beaverton, OR USA
[11] George Washington Univ, Childrens Natl Hosp, Sch Med & Hlth Sci, Div Oncol, Washington, DC 20052 USA
[12] George Washington Univ, Dept Pediat, Sch Med & Hlth Sci, Washington, DC 20052 USA