Reduced-intensity hematopoietic stem-cell transplantation for malignant lymphoma: a retrospective survey of 112 adult patients in Japan

We conducted a nation-wide survey of 112 adult Japanese patients who underwent reduced-intensity stem cell transplantation (RIST) from 1999 to 2002. Underlying diseases included indolent ( n = 45), aggressive ( n = 58) and highly aggressive lymphomas ( n = 9). Median age of the patients was 49 years. A total of 40 patients (36%) had relapsed diseases after autologous stem cell transplantation and 36 patients (32%) had received radiotherapy. RIST regimens were fludarabine-based ( n = 95), low-dose total body irradiation-based ( n = 6) and others ( n = 11). Cumulative incidences of grade II - IV acute graft-versus-host disease (GVHD) and chronic GVHD were, respectively, 49 and 59%. Cumulative incidences of progression and progression-free mortality were 18 and 25%, respectively. With a median follow-up of 23.9 months, 3-year overall survival rates were 59%. A multivariate analysis identified three significant factors for progression, which are history of radiation ( relative risk (RR) 3.45, confidential interval (CI) 1.12 - 10.0, P = 0.03), central nervous system involvement ( RR 6.25, CI 2.08 - 20.0, P = 0.001) and development of GVHD ( RR 0.28, CI 0.090 - 0.86, P = 0.026). RIST may have decreased the rate of transplant-related mortality, and GVHD may have induced a graft-versus-lymphoma effect. However, whether or not these potential benefits can be directly translated into improved patient survival should be evaluated in further studies.