Reduced-intensity conditioning allogeneic stem cell transplantation for relapsed/refractory mantle cell lymphoma: a multicenter experience

Despite therapeutic approach that combines rituximab-containing chemotherapy, followed or not by autologous stem cell transplantation (auto-SCT), mantle cell lymphoma (MCL) patients experience relapses. Reduced-intensity conditioning allogeneic stem cell transplantation (RIC-allo-SCT) at time of relapse may represent an attractive strategy. We report a multicenter retrospective analysis. Seventy MCL patients underwent RIC-allo-SCT in 12 centers. Median age at transplantation was 56 years and median time from diagnosis to transplantation was 44 months. The median number of previous therapies was 2 (range, 1–5) including autologous transplantation in 47 cases. At time of transplantation, 35 patients were in complete remission, 20 were in partial response and 15 in stable disease or progressive disease. The median follow-up for living patients was 24 months. The 2-year event-free survival (EFS) and overall survival (OS) rates were 50% and 53%, respectively. The 1- and 2-year transplant-related mortality rates were 22% and 32%, respectively. The statistical analysis demonstrated that disease status at transplantation was the only parameter influencing EFS and OS. These results suggest that RIC-allo-SCT may be an effective therapy in MCL patients with a chemo-sensitive disease at time of transplantation, irrespective of the number of lines of prior therapy. Studies are warranted to investigate the best type of RIC regimen.