Background
A better understanding of when cure can be declared in childhood acute myeloid leukemia (AML) would reduce anxiety and improve quality of life of AML survivors. We determined the likelihood of patients with AML to maintain long-term remission after completion of therapy.
Patients and Methods
The cumulative risk of relapse, time to relapse, event-free survival and overall survival were analyzed for 604 patients with AML enrolled in seven successive clinical trials, divided into 3 treatment eras (1976–1991, 1991–1997, 2002–2008).
Results
The median time to relapse did not change over time (0.93 years vs. 0.76 vs. 0.8 years for each consecutive era, P = .22) but the risk of relapse decreased significantly (5-year cumulative incidence of relapse 52.6% ± 3.1% vs. 31.5% ± 3.9% vs. 22.0% ± 3.0%, P < .001). Among patients who were in remission 4 years from diagnosis, the probabilities of relapse were 1.7%, 2.9%, and 0.9%, respectively. In the most recent era, all 44 relapses except one occurred within four years of diagnosis.
Conclusion
Children with AML who are treated with contemporary therapy and remain in remission four years from diagnosis are likely cured. Although late relapses and late deaths from other causes are rare, long-term follow up of survivors is necessary for timely management of late adverse effects.