1. From the Children's Hospital Cleveland Clinic, Cleveland; Children's Hospital, Columbus, OH; University of Nebraska Medical Center, Omaha, NE; University of Iowa College of Medicine, Iowa City, IA; Children's Hospital, Pittsburgh, PA; Memorial Sloan-Kettering Cancer Center, New York, NY; University of Oklahoma Medical Science Center, Oklahoma City, OK; Duke University Medical Center; EMD Pharmaceuticals Inc, Durham, NC; and the Children's Oncology Group, Arcadia, CA