Trisomy 8 is the most common chromosomal change in AML, as sole aberration in 5 % of cytogenetically abnormal cases and occurring together with other abnormalities in an additional 10% and little is known about the pathogenetic impact of trisomy 8. Most studies reported trisomy 8 in AML to be associated with intermediate risk. However, some reports have identified a poorer outcome than is usually seen in the intermediate group, considering trisomy 8 an adverse prognostic factor. More importantly, the clinical behavior and outcome of patients with trisomy 8 who are treated with hematopoietic stem cell transplantation (HSCT) is not known. We investigated the outcome in patients with trisomy 8 who were treated with HSCT.
Bone marrow conventional cytogenetic and FISH data from 110 adult AML patients was reviewed and patients divided into three cytogenetic risk groups according to the European LeukemiaNet reporting system while separating patients with trisomy 8 into another, fourth, independent group. Patients with trisomy 8 as part of a complex karyotype (complex = 3 or more abnormalities) were excluded. We also compared outcome of patients with trisomy 8 to the intermediate-risk group alone and adverse-risk group alone, respectively. The AML cohort included 62 (56%) patients treated in their first remission (CR1) while most non-CR1 AML patients were treated with HSCT in CR2. The median age of all patients was 25 years (range: 14–58).
Patients with trisomy 8 were 9 (8%). Patients with trisomy 8 showed significantly longer overall survival (OS) (P=0.02) and event-free survival (EFS) (P=0.03) as compared to patients with adverse cytogenetics. The outcome of trisomy 8-positive patients was similar to the intermediate-risk group.
This data suggests that trisomy 8 in AML is an intermediate-risk factor when patients are treated with HSCT. While we did not compare the outcome of HSCT with the outcome of trisomy 8-positive patients treated with intensive chemotherapy, most likely the cytogenetic risk of trisomy 8 for patients after HSCT is similar to their cytogenetic risk when treated with chemotherapy.
No relevant conflicts of interest to declare.
Asterisk with author names denotes non-ASH members.