A previously unknown subgroup of high-risk leukaemia in children has been revealed with a new, more accurate DNA test.
Researchers at the Children’s Cancer Institute (CCI) in Sydney, together with collaborators in Prague, have found a new technique for tracking leukaemia cells containing a genetic change called BCR-ABL1.
The new DNA test has proven to be more accurate than standard Minimal Residual Disease (MRD) testing currently used for patients with BCR-ABL-positive leukaemia.
The new test has revealed a biological diversity amongst this high-risk subgroup – in about 20% of children with this gene change, their leukaemia cells resembled chronic myeloid leukaemia (CML), the most common leukaemia in adults.
This discovery is surprising but important, because treatment choices for CML can differ to those for acute lymphoblastic leukaemia (ALL), the most common type of childhood cancer.
Knowing which children are part of this subgroup will allow clinicians to make better decisions about treatments to maximise effectiveness and minimise side effects. Current treatment options for BCR-ABL-positive leukaemia include drugs targeted directly at BCR-ABL1, chemotherapy and bone marrow transplantation.
A/Prof Rosemary Sutton is head of the MRD group and one of the authors. She says that while the number of children with this newly-identified type of leukaemia is low, she is enthusiastic about the implications of this study for their treatment.
“I’m most excited about our capacity to do our MRD testing in a new and different way to benefit children with BCR-ABL-positive leukaemia, particularly this CML-like subtype of ALL.
“Now that we can test for the BCR-ABL1 gene directly, it will help identify the best treatment options for children in this high-risk group,” she said.
The findings were announced in a research paper recently published online in the journal Blood.
The research was funded by grants from the National Health and Medical Research Council (NHMRC) and Cancer Council NSW.
This news was first published on the CCI website. Image: Jodie Giles (left) and Nicola Venn (right), research paper co-authors, look at DNA test results in the MRD lab, courtesy of CCI.
The Australian Cancer Research Foundation has supported cancer research at the Children’s Cancer Institute by providing three grants, totalling AUD$ 5.2 M, for the purchase of cutting edge research equipment and technology.