Allogeneic haemopoietic stem cell transplantation for multiple myeloma or plasma cell leukaemia using fractionated total body radiation and high-dose melphalan conditioning

Abstract

We have evaluated the outcome of allogeneic haemopoietic stem cell transplantation for multiple myeloma using a conditioning regimen comprising fractionated total body irradiation and high-dose melphalan (110 mg/m2). The study comprised 25 patients (median age 49 years) who had been transplanted by either bone marrow (n = 13) or G-CSF mobilized peripheral blood stem cells (n = 12). Overall transplant-related mortality was 30% but was lower for patients < 50 years of age at transplant (21%). The main cause of treatment-related mortality was viral infection. Of the 19 patients evaluable post-transplant, 17 have so far achieved complete remissions. Currently, with a median follow-up of 3.4 years, 18 out of 25 patients are alive, of whom 15 are in continuing complete remission (CR) and 2 in second remission after suffering localized relapses, which were treated with radiotherapy and donor leucocyte infusions. Patients transplanted after 1 line of previous therapy, < 50 years of age and receiving peripheral blood stem cells (PBSC) rather than bone marrow (BM) had a superior outcome, although there was no statistically significant factor. We conclude that allogeneic transplantation should be considered as a potentially curative option for younger patients with myeloma and that the regimen using fractionated total body irradiation and melphalan has a high CR rate and a relatively low risk of treatment-related mortality, particularly in younger patients.