Bone Marrow Transplantation (2001) 27, 511–515  2001 Nature Publishing Group All rights reserved 0268–3369/01 $15.00 www.nature.com/bmt Myeloma Alpha-interferon maintenance treatment is associated with improved survival after high-dose treatment and autologous stem cell transplantation in patients with multiple myeloma: a retrospective registry study from the European Group for Blood and Marrow Transplantation (EBMT) B Bjo¨rkstrand 1 , H Svensson 1 , H Goldschmidt 2 , P Ljungman 1 , J Apperley 3 , F Mandelli 4 , R Marcus 5 , M Boogaerts 6 , A Alegre 7 , K Remes 8 , JJ Cornelissen 9 , J Blade´ 10 , S Lenhoff 11 , A Iriondo 12 , K Carlson 13 , L Volin 14 , T Littlewood 15 , AH Goldstone 16 , J San Miguel 17 , A Schattenberg 18 and G Gahrton 1 , on behalf of the EBMT Myeloma Subcommittee 1 Dept of Medicine, Karolinska Institute and Huddinge Hospital, Huddinge, Sweden; 2 Dept of Medicine, University of Heidelberg, Germany; 3 Dept of Haematology, Imperial College at the Hammersmith Hospital, London, UK; 4 Dept of Hematology, University ‘La Sapienza’, Rome, Italy; 5 Dept of Haematology, Addenbrooke’s Hospital, Cambridge, UK; 6 Dept of Hematology, University Hospital Gasthuisberg, Leuven, Belgium; 7 Dept of Hematology, Hospital de la Princesa, Madrid, Spain; 8 Dept of Medicine, University Central Hospital, Turku, Finland; 9 Daniel den Hoed Cancer Center, Rotterdam, The Netherlands; 10 Dept of Hematology, Hospital Clinic, Barcelona, Spain; 11 Dept of Hematology, University Hospital, Lund, Sweden; 12 Hospital Universitario, Santander, Spain; 13 Dept of Medicine, University Hospital, Uppsala, Sweden; 14 Dept of Medicine, University Central Hospital, Helsinki, Finland; 15 Dept of Haematology, Radcliffe Hospital, Oxford, UK; 16 Dept of Haematology, University College Hospital, London, UK; 17 Dept of Hematology, Hospital Cli ´ nico, Salamanca, Spain; and 18 Div of Hematology, University Hospital St Radboud, Nijmegen, The Netherlands Summary: The purpose of this study was to evaluate the effect of alpha-IFN maintenance treatment after autologous stem cell transplantation (ASCT) for multiple myeloma in a retrospective registry analysis. 473 patients with mul- tiple myeloma who received IFN maintenance treatment ASCT were compared with 419 patients who did not receive IFN-treatment. Patients who were evaluable for response and in complete or partial remission at 6 months after ASCT were eligible, after excluding patients with graft failure. Cox proportional hazards assumptions were checked and handled by stratifi- cation. The prognostic variables unevenly distributed between the two groups were statistically corrected for in the Cox analysis. 391 patients reached complete remission (CR) after ASCT (203 in the IFN group and 188 in the no-IFN group) and 501 were in partial remission (PR, IFN 270, no-IFN 231). Overall survival (OS) and progression-free survival (PFS) were signifi- cantly better in the IFN-group (OS, 78 vs 47 months, P = 0.007, and PFS, 29 vs 20 months, P = 0.006, respectively). The difference in OS and PFS was most strongly pronounced in the PR patients. 209 patients have died (IFN, 84; no-IFN, 125). Progressive myeloma Correspondence: Dr B Bjo¨rkstrand, Department of Hematology, M54, Huddinge University Hospital, SE-141 86 Huddinge, Sweden Received 26 May 2000; accepted 14 December 2000 was the cause of death in 94% of the IFN-treated patients and in 83% of the no-IFN group (P = NS). Thus, IFN maintenance treatment after ASCT was asso- ciated with better OS and PFS. Treatment seemed to be most beneficial in patients who did not achieve CR. The difference in median survival was as long as 2.5 years, and although part of this difference is attributable to differences in other prognostic factors, it might justify possible differences in quality-of-life due to adverse effects of interferon treatment. Bone Marrow Transplan- tation (2001) 27, 511–515. Keywords: multiple myeloma; autologous stem cell transplantation; alpha-interferon Multiple myeloma (MM) is a malignant hematological dis- ease most common in the elderly. Although usually sensi- tive to chemotherapy with cytotoxic drugs, such treatment rarely induces complete remission and never cure, and after various periods of time most patients succumb due to dis- ease progression. For younger patients, allogeneic bone marrow transplantation may induce long-term remissions and maybe cure in some patients, but this method has hith- erto been hampered by the high rate of fatal transplant- related toxicity. 1 Currently, the best treatment option for patients under the age of 60 to 65 years is high-dose cyto- toxic treatment with autologous hematopoietic stem cell transplantation (ASCT), which has been demonstrated to be superior to conventional combination chemotherapy for