1. From the Department of Hematology and Stem Cell Transplantation, West German Cancer Center, University Hospital Essen, University of Duisburg-Essen, Essen, Germany (A.R.); Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Cà Granda Ospedale Maggiore Policlinico, Milan, Italy (W.B.); the Centre for Waldenström’s Macroglobulinaemia and Related Conditions, University College London Hospitals National Health Service Foundation Trust, London (S.D.); the Thrombosis and Hemostasis Center, Saitama...