1. Second Medical Department, University Hospital Schleswig-Holstein, Campus Kiel, Kiel, Germany;
2. Department of Internal Medicine III, University of Munich, Grosshadern, Germany;
3. Assistance Publique-Hopitaux de Paris, Hôpital Henri-Mondor, Immunology Department, Inserm U955, Equipe 9, Université Paris XII, Créteil, France, for the Groupe d'Etudes de Lymphomes de L'Adulte (GELA);
4. Laboratoire d'Hématologie, Hôpital Necker-Enfants-Malades, Paris, France, for the GELA;
5. Institute of Human Genetics, University Hospital Schleswig-Holstein, Campus Kiel, Kiel, Germany;
6. Service d'Hématologie Biologique, Centre Hospitalier Lyon Sud, Pierre-Bénite, France;
7. Department of Hematology, Rigshospitalet, Copenhagen, Denmark;
8. Department of Immunology, Erasmus MC, Rotterdam, The Netherlands;
9. Institute of Hematopathology, University Hospital Schleswig-Holstein, Campus Kiel, Kiel, Germany;
10. Department of Pathology, Centre Hospitalier Lyon-Sud, Lyon, France;
11. Laboratoire de Récherche Translationelle, Institut Gustave Roussy, Villejuif, France;
12. Department of Hematology, University Hospital St Jan, Brugge, Belgium;
13. First Department of Medicine, Charles University, Prague, Czech Republic;
14. Institute of Oncology, Maria Sklodowska-Curie Memorial Cancer Center, Warszawa, Poland;
15. Department of Medicine V, University of Heidelberg, Heidelberg, Germany;
16. Department of Hematology, University Medical Center, University of Groningen, Groningen, The Netherlands; and
17. Department of Clinical Hematology, University Paris Descartes, Centre National de la Recherche Scientifique Unite Mixte de Recherche 8147, Necker Hospital Paris, France, for the GELA