Developing a blood test to help identify high risk Wilms tumours

Wilms tumour is the commonest kidney cancer in children, with around 80 new cases in the UK each year. For almost 9 in 10 children it is now curable but despite intensive treatment, some children relapse, meaning their cancer returns. Many relapses come from a group with tumour cells that look “anaplastic” or “blastemal” down a microscope, also known as high risk tumours. The remainder of relapses do not have these features and we currently cannot predict these cases.

The aim of this study is to find ‘biomarkers’ that can identify the high risk tumours early on, as well as children who are likely to relapse. These could then be used to decide adjustments to treatment, monitor how well treatment is working and monitor for relapse. The team's priority is to find a ‘signature’, or ‘fingerprint’ of the tumour that can be detected from a simple blood test. This is to avoid the risks of performing a biopsy in small children. Also, as a biopsy only looks at a tiny section of the whole tumour, it rarely captures all relevant information.

We know that tumours release their damaged (‘mutated’) genetic code (DNA) into the bloodstream, as well as other short pieces of genetic code called microRNAs. New methods are able to detect these tiny quantities of tumour DNA and microRNA directly, and potentially tell us a lot about the composition of the tumour. The team will be applying these methods to tumours and to blood from the same patients. They will focus on time points before surgical removal of the tumour (to see how early we can identify high risk tumours) and afterwards (to check for relapse).

Monitoring microRNA and circulating tumour DNA, with reference to the known mutations in the tumour itself, could allow doctors to keep track of how treatment is working, give early indications of tumours with a high risk of recurrence, and directly detect if the tumour has returned.