1. Department of Hematology, University Hospital Basel, Basel, Switzerland;
2. Division of Hematology and Clinical Immunology, Department of Clinical Medicine, University of Perugia, Perugia, Italy;
3. Oncoematologia Pediatrica, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Policlinico San Matteo, Università di Pavia, Pavia, Italy; and
4. Department of Pediatrics, Division of Hematology-Oncology, Blood and Marrow Transplantation, University of Minnesota, Minneapolis