Allogeneic Hematopoietic Stem-Cell Transplantation After Nonmyeloablative Preparative Regimens: Impact of Pretransplantation and Posttransplantation Factors on Outcome

PURPOSE: To analyze the impact of pre- and posttransplantation factors on the outcome of allogeneic transplantation after nonmyeloablative conditioning regimens. PATIENTS AND METHODS: Ninety-two allogeneic transplantations after nonmyeloablative preparative regimens were reported to the Société Française de Greffe de Moelle Registry registry. Initial diagnoses were lymphoid diseases (n = 22), myeloma (n = 14), acute leukemia and myelodysplasia (n = 41), chronic myelogenous leukemia (n = 12), and solid tumors (n = 3). Forty-six patients had previously received a transplant, and 49 had progressive disease before transplantation. Three types of conditioning regimens were used with fludarabine or antithymocyte globulins. Eighty-nine patients underwent transplantation, 60 from peripheral-blood progenitor cells. Eighty-six patients received graft-versus-host disease (GHVD) prophylaxis for a median duration of 53 days. RESULTS: Seventy-nine patients engrafted, with 40 complete and 21 mixed chimerisms. The acute GHVD rate at 3 months was 50% ± 11%. Fifty-two patients achieved complete remission and 12, partial remission. At 18 months after transplantation, the overall survival (OS) and the transplant-related mortality (TRM) were 32% ± 12% and 38% ± 14%, respectively. Initial diagnosis and disease status before transplantation significantly influenced survival. Age and GHVD prophylaxis type significantly influenced TRM. We also showed an impact of GHVD prophylaxis duration on OS and TRM. In multivariate analysis, three factors remained of prognostic value on OS: initial diagnosis, disease status at transplantation, and GHVD prophylaxis duration. CONCLUSION: This series shows encouraging results from nonmyeloablative conditioning regimens before allotransplantation and demonstrates the impact of some pre- and posttransplantation factors on outcome after transplantation.