Allogeneic stem cell transplantation for patients with acute myeloid leukemia or myelodysplastic syndrome who have chromosome 5 and/or 7 abnormalities.

Background And Objectives: Chromosome 5 and/or 7 abnormalities are cytogenetic findings indicative of a poor prognosis in patients with acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS). The only potential cure for such patients is allogeneic stem cell transplantation (SCT). As data on allogeneic SCT in this context are limited we did a retrospective study of allogeneic SCT in patients with AML or MDS who had chromosome 5 and/or 7 abnormalities.

Design And Methods: This was a retrospective study of 65 patients (16 children, 49 adults) with AML (n=33) or MDS (n=32) who had chromosome 5 and/or 7 abnormalities and who underwent allogeneic SCT in six Dutch Centers between 1983 and 2001. Data on all these patients are recorded in the Netherlands Stem Cell Transplant Registry (Typhon).

Results: The 3-year overall survival rate among all patients was 25%. Patients below the age of 40 years had significantly fewer relapses (40%) and better survival (38%) than those above the age of 40 (86% and 8%, respectively). Relapses were less frequent in recipients of unrelated grafts than in those whose grafts were from HLA-identical siblings (30% versus 69%). The development of acute graft-versus-host disease (GVHD) grades II-IV was independently associated with significantly higher transplant-related mortality (TRM). Patients with either chromosome 5 or chromosome 7 abnormalities had a significantly better survival than patients with both chromosome 5 and 7 abnormalities. These patients with poor-risk chromosome 5 and/or 7 abnormalities were compared with a group of patients with a secondary AML/MDS and normal cytogenetics and were found to have significantly more relapses and significantly worse survival but a similar TRM.

Interpretation And Conclusions: We conclude that patients with AML or MDS with chromosome 5 and/or 7 abnormalities do rather poorly after allogeneic SCT, mainly because of the very high relapse rate. Nevertheless, this is the only approach that can cure some of these patients.