NEW YORK (Reuters Health) – Patients with acute myeloid leukemia (AML) who do not receive a stem-cell transplant during first remission and then relapse have a fair chance of achieving a second remission with salvage treatment, especially when it includes a transplant, a UK team reports.
“This result suggests that, for intermediate-risk patients in particular, equivalent overall survival can be achieved by delaying transplantation until after relapse, which would require many fewer transplants,” the investigators conclude in their paper in the Journal of Clinical Oncology online February 25.
Dr. Alan K. Burnett, at Cardiff University School of Medicine, and colleagues explain that questions concerning which AML patients should receive an allogeneic stem-cell transplant (SCT), and when, are still debated. There is little information about the strategy of delaying an SCT until relapse occurs, although this approach could provide advantages in terms of survival and quality of life as well as economic benefits.
To investigate that issue, the authors analyzed data on 3919 AML patients aged 16 to 49 years who participated in three trials. In this cohort, 3415 patients (87%) entered remission; 1064 of them received a transplant while 232 died in first remission. Among the remaining 2119 remitted patients who were not transplanted, 1271 (60%) relapsed during first remission (CR1).
Among those 1271 patients, 642 achieved a second remission (CR2) without a prior SCT. While in CR2, 433 underwent allogeneic transplantation while 209 did not.
Overall, with salvage treatment, 19% of the patients who received only chemotherapy before relapsing after first remission survived for at least 5 years, “whereas only 7% survived if they relapsed after transplant,” according to the report.
Among the patients who relapsed after first remission and then entered CR2, 5-year survival was 34%. However, it was significantly higher among those who were transplanted (42%) than among those who were not (16%).
Further analysis by risk group indicated that transplantation post-relapse clearly benefitted patients with intermediate-risk disease and less clearly those with adverse-risk disease, but not those in the favorable-risk category, the authors report.
In discussing their findings, Dr. Burnett and colleagues write, “The data suggest the possibility of producing the same number of survivors overall by reserving transplantation for relapse, which would require many fewer transplants and avoid the transplant-associated morbidity and extra health-related interventions.”
Still, factors affecting transplantation decisions may well change, they caution. “Several new prognostic factors will further stratify the relapse risk in intermediate patients; however, it cannot be assumed that adverse features are automatically improved by a transplant,” they point out. On the other hand, “The safety of transplantation may improve and the earlier detection of a relapse by molecular or immunophenotypic methods may enable a more effective intervention.”
SOURCE: If at First You Don’t Succeed: Stem-Cell Transplantation for Acute Myeloid Leukemia After First Relapse
J Clin Oncol 2013;30.
