High-Risk Acute Lymphoblastic Leukemia Subtype Identified
Development of gene expression classification system identifies new subtype with poor prognosis
FRIDAY, Jan. 9 (HealthDay News) -- Identification of the major subtypes of childhood acute lymphoblastic leukemia (ALL), including a newly identified high-risk subtype (BCR-ABL1), may be improved with the use of a classification system based on gene expression, according to research published online Jan. 9 in The Lancet Oncology.
Monique L. Den Boer, Ph.D., of the Sophia Children's Hospital in Rotterdam, the Netherlands, and colleagues analyzed gene expression patterns in order to determine their association with ALL classification and prognosis. The gene expression patterns were evaluated in 190 children with newly diagnosed ALL. These patterns were used by the investigators to construct a classification system, which was then validated in an independent group of 107 similarly diagnosed children.
The gene classification system correctly identified the ALL subtype with a median accuracy of 87.9 percent in the validation cohort, the researchers report. Importantly, the investigators discovered that a number of children who would have otherwise been classified with B-other ALL actually displayed a gene expression pattern that clustered with the BCR-ABL1-positive subtype. These children were designated as having a BCR-ABL1-like subtype of ALL. Patients with this subtype had a poor prognosis and were determined to be high-risk, the authors note.
"Because the new BCR-ABL1-like subtype is the most common poor-prognostic subtype of childhood ALL, improved treatment of this high-risk leukemia should have a great effect on the overall cure rate of childhood ALL," Den Boer and colleagues conclude.
Two of the study authors report the submission of a patent application related to this work.