Prognostic Impact of Specific Chromosomal Aberrations in a Large Group of Pediatric Patients With Acute Myeloid Leukemia Treated Uniformly According to Trial AML-BFM 98
Abstract
Because cytogenetic data are essential for risk stratification of childhood acute myeloid leukemia (AML), the impact of chromosomal aberrations is crucial. Patients and Methods Data of a large group of patients younger than 18 years treated according to study AML-Berlin-Frankfurt- Munster (BFM) 98 (n = 454), including their cytogenetics, were analyzed.
Results The favorable outcome in the subgroups of patients with t(8;21), inv(16), and t( 15; 17), with an overall survival of 91% (SE,4%), 92% (SE,6%), and 87% (SE,5%), respectively, was confirmed. Within this group, the 5-year probability of event-free survival (pEFS) of all 17 children with t( 8; 21) and additional aberrations apart from del(9q) or -X/-Y was 100%.
As expected, the cytogenetic finding of a complex karyotype (n = 35; pEFS, 33%; SE, 8%) or a monosomy 7 (n = 12; pEFS, 17%; SE, 11%) was associated with a poor outcome. Compared with remaining patients with cytogenetic data ( pEFS, 48%; SE, 2%), prognosis in patients with an MLL rearrangement (n = 91) was inferior ( pEFS, 34%; SE, 5%; P = .0005).
Particularly, children with t( 9; 11) and additional aberrations (n = 13; pEFS, 31%; SE, 14%) and MLL rearrangements other than t( 9; 11) and t( 11; 19) (n = 41; pEFS, 24%; SE, 7%) had an unfavorable outcome. Nine patients with aberrations in 12p showed an adverse prognosis ( pEFS, 11%; SE, 10%).
The outcome of patients with aberrations of chromosome 5 (n = 13) was better than expected ( pEFS, 50%; SE, 13%). Conclusion Because the prognostic value of rare recurrent chromosomal aberrations still has to be elucidated, these data will contribute to future risk stratification for the treatment of pediatric AML.