By the start of the 1990s scientists were beginning to understand more and more about how leukaemia develops in children.
It was around this time that doctors firmly established the difference between childhood ALL, which is a distinct disease in children, and AML, which is a very similar disease in adults and children. This is why children with different forms of leukaemia do not respond to the same treatments.
Finding the cause
In the early 1990s, we invested in the far-reaching UK Childhood Cancer Study, which was set up to look at the underlying environmental factors that may cause leukaemia in children.
Findings from the study have contributed hugely to identifying a link between how the immune system responds to infection and the development of ALL.
The 1990s also saw us back the development of the minimal residual disease (MRD) test, which was designed to accurately guide treatment for children with leukaemia. The test detects the number of leukaemia cells in the blood of a child at an accuracy of 1 in 10,000 cells.
Knowing how few leukaemia cells are in a child’s blood at an early stage has revolutionised how treatment intensity is managed. It allows doctors to identify those children that can be spared intensive chemotherapy and its side-effects and those children who will need high intensity treatment to be cured.
In 2003, after successfully being tested in the UKALL trials, the MRD test became a standard part of every child’s treatment and is now being paid for by the NHS.
In conjunction with the UKALL trials, we opened up cell banks around the UK to store samples of cells and DNA from children who have been treated for leukaemia. This vital resource has enabled our scientists to understand more about the biology of these diseases and continue improving treatments.
In the late 1990s we launched the Cytogenetics Database to better understand the genetics behind childhood leukaemia. Cytogenetics is a branch of genetic research that looks at chromosomes, the structures found within cells that carry DNA. To date the cytogenetics team has studied samples from more than 25,000 adults and children with acute leukaemia in the UK, providing new insights into specific genetic mutations and how these can be used to guide treatments for individual patients.
In 2003 the cytogenetics team discovered that children with multiple copies of a particular gene respond poorly to treatment. This information was fed into the current UKALL trial and children were screened to identify those who would benefit from intensive treatment, leading to an increase in survival rates.