1. Unit of Lymphoid Malignancies, Department of Oncology, San Raffaele Scientific Institute, Milan, Italy; International Extranodal Lymphoma Study Group, Bellinzona, Switzerland
2. Department of Hematology and Lymphoma, Evangelismos Hospital, Athens, Greece
3. University Hospital of Essen, Essen, Germany
4. Centre Hospitalier Universitaire Hôtel-Dieu, Clermont-Ferrand, France
5. Centre Hospitalier Universitaire Lille, Lille, France
6. The Ohio State University, Columbus, OH
7. Centre Henri Becquerel, Rouen, France
8. National Tuberculosis and Lung Diseases Research Institute, Warsaw, Poland
9. Clinica di Ematologia, Azienda Ospedali Riuniti di Ancona, Ancona, Italy
10. First Department of Medicine, University of Pecs, Pecs, Hungary
11. International Extranodal Lymphoma Study Group, Bellinzona, Switzerland; Division of Medical Oncology, Istituto Oncologico della Svizzera Italiana, Bellinzona, Switzerland
12. Unit of Lymphoid Malignancies and Pathology Unit, Department of Oncology, San Raffaele Scientific Institute, Milan, Italy; International Extranodal Lymphoma Study Group, Bellinzona, Switzerland