1. From the Departments of Paediatric Oncology, Biostatistics, and Pathology, Institut Gustave Roussy, Villejuif; Department of Paediatric Oncology, Centre Oscar Lambret, Lille; Department of Paediatric Oncology, Centre Léon Bérard, Lyon, France; Department of Paediatric Oncology, Hôpital Michalon, Grenoble; Department of Paediatric Oncology, Hôpital d'enfants, Nancy; Department of Paediatric Oncology, Centre hospitalo-universitaire, Besançon; Department of Paediatric Oncology, Hôpital Clocheville, Tours;...