Pretreatment Cytogenetic Abnormalities Are Predictive of Induction Success, Cumulative Incidence of Relapse and Overall Survival in Patients >60 Years of Age with Newly Diagnosed Acute Myeloid Leukemia.

Purpose: Karyotype at diagnosis provides the most important prognostic information in younger adults with acute myeloid leukemia (AML). However, there are few data available looking in particular at patients (pts.) above 60 years of age. We prospectively analyzed 361 elderly pts. with newly diagnosed AML. All pts. were treated within the AMLHD98B treatment trial and received intensive induction and consolidation therapy. Pts. exhibiting a t(15;17) received an age-adjusted AIDA-regimen. Median follow-up time was 48 months. The median age was 67 years (range 60–85 years).

Results: 160 pts. had a normal karyotype (44%); 48 pts. (13%) exhibited the balanced translocations t(8;21) (n=12), inv(16) (n=14), t(15;17) (n=11), or t(11q23) (n=11); in the absence of these balanced translocations, 73 pts. exhibited a single aberration, 179 pts. two aberrations, and 61 pts. a complex karyotype (≥3 aberrations; including 44 pts. with 5 or more aberrations). Analyses were normalized to the complete remission (CR) rate (52%), cumulative incidence of relapse (CIR) (77%) and overall survival (OS) (13%) after 4 years of pts. with normal karyotype. Pts. exhibiting a t(15;17) showed a significantly better CIR (29%) and OS (55%), whereas pts. with the other balanced translocations [t(8;21), inv(16)/t(16;16) and t(11q23)] did not differ from pts. with normal karyotype. The limited backward selected Cox-model for OS [t(15;17) excluded] revealed two risk groups: standard-risk [normal karyotype, t(8;21), inv(16), t(11q23), +8 and +11 in absence of a complex karyoytpe] and high-risk [all other aberrations]. The CR rates were 56% and 18%, and the OS-rates after 4 years for the standard- (n=223) and the high-risk group (n=127) were 15% and 0%, respectively. The MRC risk classification system for patients >55 years applied to our patients revealed CR- and OS-rates after 4 years of 73% and 19%, 47% and 12%, as well as 7% and 0% for the low (n=26), intermediate (n=282) and high risk groups (n=44), respectively [t(15;17) excluded]. In conclusion, our risk classification system identified a large high-risk group (36%) of elderly patients with AML who did not benefit from intensive chemotherapy.