Prognostic factors of long-term survival in patients with acute myeloid leukemia after allogeneic or autologous stem cell transplantation.

Abstract

6594 Background: The purpose of this study is to provide a long-term survival analysis for patients with acute myeloid leukemia (AML) after allogeneic or autologous stem cell transplantation (SCT). Methods: The patients included were 210 AML patients treated at Hahnemann University Hospital from 1980 through 2004. End points were overall survival (OS) and progression-free survival (PFS) calculated by Kaplan-Meier method. Results: We showed a statistically significant long-term survival advantage when transplantation was performed in the first complete remission (CR1) as opposed to subsequent remissions or relapse (median OS: 97 months vs 17 months vs 3 months for allogeneic SCT, and 38 months vs 13 months vs 4 months for autologous SCT, p<0.001). Compared to autologous SCT, there was a 60% improvement in median OS for patients treated with allogeneic SCT in CR1 (p=0.025). Among AML subtypes, a trend toward improved survival was noted for M2 following allogeneic, but not autologous, SCT. The median OS was not reached for M2 after 20 years follow-up (P<0.08). Although severe graft versus host disease (GVHD) was associated with early transplant-related mortality, occurrence of grade I and II acute or limited chronic GVHD had favorable long-term survival. On the contrary, veno-occlusive disease (VOD) of the liver had little impact on long-term survival. We also compared outcomes of overall survival for patients who received different pre-transplant conditioning regimens after allogeneic SCT. Compared to BU/CY4 (busulfan 16mg/kg plus cyclophosphamide 200mg/kg given over 4 days) and BU/CY/VP (busulfan 16mg/kg, cyclophosphamide 120mg/kg, VP16 40mg/kg), BU/CY2 (busulfan 16mg/kg plus cyclophosphamide 120mg/kg given over 2 days) was associated with a significantly improved long-term survival (59.6% vs 27.3% vs 15.5% at 10 years, P< 0.001). Conclusions: These results demonstrated a superior overall survival in AML patients who received allogeneic SCT in CR1 compared to autologous SCT at the same remission status. AML subclasses, pre-transplant conditioning regimens, and grade I/II GVHD are additional factors contributing to long-term survival after allogeneic SCT.