1. Department of Pediatric Surgery, Hopitaux Universitaires de Geneve Hopital des Enfants, Geneva, Switzerland
2. Department of Pediatric Hemato-oncology, Hopitaux Universitaires de Geneve Hopital des Enfants, Geneva, Switzerland
3. Unit of Pediatric Hemato-oncology, Centre Hospitalier Universitaire Vaudois, Lausanne, Canton of Vaud, Switzerland
4. Division of Clinical Pathology, Hopitaux Universitaires de Geneve, Geneva University Hospitals, Geneva, Switzerland