Autologous hematopoietic stem-cell transplantation for children with acute myeloid leukemia in first or second complete remission: a prognostic factor analysis.

Purpose: To determine prognostic factors correlated with outcomes after autologous hematopoietic stem-cell transplantation (HSCT) in children with acute myeloid leukemia (AML).
Patients and Methods: We studied 219 children who received autologous HSCT for AML in first complete remission (CR) and 73 children in second CR and who were reported to the Autologous Blood and Marrow Transplant Registry. Among 29 of 73 patients who underwent transplantation in second CR, duration of first CR was > or = 12 months.
Results: Three-year cumulative incidences of relapse were 37% (95% CI, 31% to 44%), 60% (95% CI, 41% to 74%), and 36% (95% CI, 20% to 53%) for children in first CR, second CR after a short (< 12 months) first CR, and second CR after a long (> or = 12 months) first CR, respectively. Corresponding 3-year probabilities of leukemia-free survival were 54% (95% CI, 47% to 60%), 23% (95% CI, 10% to 39%), and 60% (95% CI, 42% to 75%). In multivariate analyses, risks of relapse, mortality, and treatment failure (relapse or death, inverse of leukemia-free survival) were higher for patients in second CR after a short first CR than for the other two groups. Transplant-related mortality, treatment failure, and overall mortality rates were higher in older (> 10 years) children.
Conclusion: Duration of first CR seems to be the most important determinant of outcome. Results in children who experience treatment failure with conventional chemotherapy support the use of autologous transplantation as salvage therapy if such patients achieve a subsequent CR.