1. Pediatric Hematology/Oncology; Children's Hospital; Hannover Medical School; Hannover Germany
2. Department of Pediatrics; Division of Hematology/Oncology; University of Alabama at Birmingham; Birmingham Alabama
3. Departments of Pediatrics, Pathology and Medicine; McMaster University; Hamilton Canada
4. National Center for Tumor Diseases (NCT); Heidelberg Germany
5. Department of Hematology/Oncology; St. Jude Children's Research Hospital; Memphis Tennessee