[1090] Reduced Intensity Conditioning (RIC) Allogeneic Stem Cell Transplantation (allo-SCT) for Patients with Acute Myeloid Leukemia (AML): Long Term Results of a Donor Versus No Donor Comparison. Session Type: Poster Session, Board #244-I

Mohamad Mohty, Hugues de Lavallade, Jean El-Cheikh, Patrick Ladaique, Catherine Faucher, Sabine Furst, Norbert Vey, Diane Coso, Anne-Marie Stoppa, Jean-Albert Gastaut, Christian Chabannon, Didier Blaise Institut Paoli-Calmettes, Marseille, France

RIC regimens have emerged as an attractive modality to decrease transplant-related toxicity (TRM). However, the potential higher relapse rate after RIC allo-SCT is still under considerable debate. This report describes the long term results of 95 consecutive AML patients, diagnosed between Nov. 1999 and Dec. 2003 in a single institution, and who were considered as potential candidates for RIC-allo-SCT. Using a genetic randomization through a donor versus no donor comparison, the aim was to assess the real benefit of RIC-allo-SCT for adult AML and its impact on outcome. In this series, 35 patients (37%; donor group) had an identified HLA-identical sibling donor, while the remaining 60 patients had no HLA-matched related donor (no donor group). As per institutional policy, HLA-matched unrelated donors were not considered during the study period. No significant differences in patients or AML features were found between the two groups. In the donor group, 25 patients (71%; median age, 51 (range, 26-60)) could actually proceed to the RIC-allo-SCT. The 10 remaining patients with an identified donor did not receive allo-SCT because of early relapse after CR (n=2), patient or donor refusal (n=6), and psychiatric disorders appearing before allo-SCT (n=2). The current median follow-up is 60 months. In an intention-to-treat analysis, the KM estimate of leukemia-free survival (LFS) was significantly higher in the donor group as compared to the no donor group (P=0.003; 60% versus 23% at 7 years). When restricting the analysis to patients who could actually receive the RIC-allo-SCT (median follow-up, 40 months from time of allo-SCT), the difference in LFS was also significant between this group of 25 patients (transplant group) and the remaining 70 patients (no transplant group) who did not receive allo-SCT (P=0.0002; 72% versus 24% at 7 years). In the transplant group, RIC-allo-SCT was performed at a median of 209 (range, 119-413) days after diagnosis. No major toxicities were encountered during RIC administration (fludarabine, busulfan and ATG), and only 3 patients died from TRM, for a cumulative incidence of 12% (95%CI, 3-32%) at last follow-up. This relatively low TRM translated towards a significantly higher overall survival (OS) in the transplant group as compared to the no transplant group (P=0.0003). In the intention-to-treat analysis, OS was still significantly higher in the donor group as compared to the no donor group (P=0.003; Figure below). After controlling for relevant factors, in the multivariate analysis, only actual performance of RIC-allo-SCT (P=0.0005; RR=4.1; 95%CI, 1.8-9.1), was significantly predictive of an improved LFS, further confirming the overall benefit of RIC-allo-SCT for adult AML patients. We conclude that if a matched related donor is identified, RIC-allo-SCT should be proposed since it represents a valid and potentially curative option for AML patients not eligible for standard myeloablative allo-SCT.


Abstract #1090 appears in Blood, Volume 110, issue 11, November 16, 2007
Keywords: Acute Myeloid Leukemia|Allogeneic Stem Cell Transplant|Graft versus Leukemia
Disclosure: No relevant conflicts of interest to declare.

Saturday, December 8, 2007 5:30 PM

Session Info:  Poster Session: Clinical Results: Allogeneic Matched Related Donor Transplantation I (5:30 p.m.-7:30 p.m.)