Purpose: The treatment of acute myeloid leukemia (AML) in first relapse is associated with unsatisfactory rates of complete responses that usually are short lived. Therefore, a clinically useful prognostic index can facilitate therapeutic decision making and evaluation of investigational treatment strategies at relapse of AML.
Patients and methods: A prognostic score is presented based on the multivariate analysis of 667 AML patients in first relapse among 1,540 newly diagnosed non-M3 AML patients (age 15 to 60 years) entered onto three successive Dutch-Belgian Hemato-Oncology Cooperative Group and the Swiss Group for Clinical Cancer Research Collaborative Group trials.
Results: Four clinically relevant parameters are included in this index (ie, length of relapse-free interval after first complete remission, cytogenetics at diagnosis, age at relapse, and whether previous stem-cell transplantation was performed). Using this stratification system, three risk groups were defined: a favorable prognostic group A (overall survival [OS] of 70% at 1 year and 46% at 5 years), an intermediate-risk group B (OS of 49% at 1 year and 18% at 5 years), and a poor-risk group C (OS of 16% at 1 year and 4% at 5 years).
Conclusion: The prognostic index estimates the outcome of AML patients in first relapse using four commonly applied clinical parameters and might identify patients who are candidates for salvage and investigational therapy.