1. University Hospital of Cologne; Cochrane Haematological Malignancies Group, Department I of Internal Medicine; Kerpener Str. 62 Cologne Germany 50937
2. University Hospital of Cologne; Department I of Internal Medicine; Cologne Germany 50931
3. Rigshospitalet, University of Copenhagen; Depts. of Oncology and Haematology; The Finsen Centre 9 Blegdamsvej Copenhagen Denmark DK-2100