Long-term survival of patients with acute myeloid leukemia: a third follow-up of the Fourth International Workshop on Chromosomes in Leukemia.

Background: In 1982, the Fourth International Workshop on Chromosomes in Leukemia reviewed data prospectively collected on 716 patients with acute myeloid leukemia (AML) diagnosed between 1980 and 1982. The present study examined the extended follow-up on these patients.
Methods: The analyses included cytogenetic and clinical data, with a median follow-up of 14.7 years, from 54 patients with treatment-associated AML and 628 with de novo AML. Of these patients, 291 received induction therapy that would be considered standard by today's criteria; no patient received high-dose cytarabine (HiDAC) intensification.
Results: Among the patients with treatment-associated AML, the only long-term survivor in retrospect appears to have had de novo AML. Among the patients with de novo AML, achievement of complete remission and survival varied significantly based on cytogenetic classification among all 628 patients as well as among those who did and did not receive standard induction therapy. The remission rate and survival were significantly better with standard induction therapy for patients with t(15;17) and normal cytogenetics. Multivariate analyses showed that karyotype was an independent predictor of survival for all patients and those receiving standard induction therapy. Only 8.9% of patients were alive 5 years following diagnosis, but 5 years of continuous remission was synonymous with cure. Even among 5-year survivors who had suffered a previous relapse, 41% appeared to be cured. Survival among patients in continuous remission for > or = 10 years varied significantly by cytogenetic classification. In the absence of HiDAC intensification, no complete responders with t(8;21) and only 7% with normal cytogenetics survived continuously 10 years disease free.
Conclusions: Cure of AML following specific therapies must be evaluated in the context of cytogenetics. A meta-analysis incorporating cytogenetic data is indicated for patients with > or = 10 years of follow-up.