Test for single genetic fault can predict child cancer patient survival

A study led by the ICR has shown that a simple genetic test could help predict the aggressiveness of rhabdomyosarcomas in children, so treatment can be tailored accordingly.

Rhabdomyosarcoma patients with a particular genetic fault, known as the PAX3/FOXO1 fusion gene, have significantly poorer survival rates than patients without the fault.

Dr Janet Shipley said the PAX3/FOXO1 fusion gene test “should be incorporated into standard clinical practice”.

Dr Shipley and colleagues made the conclusion after analysing data for thousands of genes from 225 rhabdomyosarcoma samples. This identified a panel of 15 gene alterations that could be used to predict how patients responded to treatment. However, these gene changes were mostly linked to the presence of the PAX3/FOXO1 fusion gene, which is much simpler and cheaper to test for than the other alterations. The test would involve scanning for the presence of the fusion gene in a sample of the patient’s tumour.

Combining the fusion gene test with two existing standard measures of risk for rhabdomyosarcomas – the patient’s age at diagnosis and the tumour’s stage of development – gave a simple but highly effective prognostic test, which could be used to divide patients into one of four risk-groups.

The test would lead to changes in treatment for many patients, allowing some children to escape potentially long-term side-effects whilst giving others the intense treatments they need to increase their chances of survival.

Using the new system, 31 per cent of patients in the study who would previously have been classified as intermediate risk would be reassigned to a lower risk group, while a further 29 per cent of intermediate-risk patients would be moved to a higher risk group.

The study was published in the Journal of Clinical Oncology.