Test for single genetic fault can predict child cancer patient survival
Monday 26 March 2012
A study led by The Institute of Cancer Research (ICR) has shown that a simple genetic test could help predict the aggressiveness of rhabdomyosarcomas in children and should be introduced into clinical practice. 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.
In a paper published online today in the Journal of Clinical Oncology, Dr Janet Shipley and collaborators in the UK, Switzerland and France found that children who have a tumour called rhabdomyosarcoma with a particular genetic fault, known as the PAX3/FOXO1 fusion gene, have significantly poorer survival rates than other rhabdomyosarcoma patients.
Children diagnosed with rhabdomyosarcoma are treated with a combination of chemotherapy and surgery and sometimes radiotherapy. These treatments have helped improve survival rates, but can cause serious and long-term side-effects including the potential to develop another cancer later in life. Having better information about how aggressively the tumour is likely to behave can help doctors to tailor treatment for each patient that balances the need for effective treatment with the side-effects of such treatment.
Dr Shipley says: “Our previous studies have raised issues with the current system of predicting patients’ risk, which is based on the appearance of patients’ tumours. Our new study finds that a simple genetic test should be incorporated into standard clinical practice as it significantly improves our ability to predict tumour aggressiveness. This fusion gene test could be used alongside other standard clinical measures to divide patients into one of four risk-groups, so that treatment can be tailored accordingly. Importantly, this will mean some patients who were previously categorised as high-risk could be able to avoid the side-effects associated with intense treatment, while others should receive the intense treatment they need to increase their chance 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.
In this study, which was funded by the Chris Lucas Trust, Cancer Research UKand La Ligue Nationale Contre le Cancer, Dr Shipley’s team analysed 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.
Lynn Lucas, whose son passed away in July 2000 after a three year battle with rhabdomyosarcoma, says the Chris Lucas Trust helped fund the team’s important research in the hope that other children and parents would be spared their ordeal.
Treatments for the cancer left Chris with serious side-effects including weight loss, difficulty walking and a painful mouth.
“Rhabdomyosarcoma is a cruel disease since children can go into remission thinking they have won the battle then find out months later it has returned even more aggressive,” she says. “The current treatments have some dreadful side-effects, which children have no choice at present but to tolerate. This test could help some children avoid this suffering, making sure only those who really need it receive intense treatment.”
Kate Law, director of clinical research at Cancer Research UK, said: “Over the last 30 years we’ve made great progress in helping more children survive cancer, since the 1970s the survival rate for rhabdomyosarcoma has more than doubled. But, some of the treatments that are behind this success have side effects and it’s important we find ways to minimise the number of children who are exposed to them.”
The study was a collaboration between the ICR, The Royal Marsden NHS Foundation Trust, the Northern Institute for Cancer Research and University College London Institute of Child Health in the UK; SIB Swiss Institute of Bioinformatics and the Centre Hospitalier Universitaire Vaudois in Switzerland, and the Institut Curie, Ligue Nationale Contre le Cancer and Institut Gustave Roussy in France.
Media Contact: ICR Science Communications Manager Jane Bunce on 0207 153 5106 or after hours 077217 47900.
Notes to editors: PAX3/FOXO1 Fusion Gene Status Is the Key Predictive Molecular Marker in Rhabdomyosarcoma and Significantly Improves Current Risk Stratification publishes today online in the Journal of Clinical Oncology.
Rhabdomyosarcoma is cancer that resembles skeletal muscle and can arise in many different locations in the body.
The fusion gene PAX3/FOX01 is the result of abnormal joining together of the PAX3 gene with the FOXO1 gene. This is thought to arise spontaneously in cells, triggering their development into cancer, and cannot be inherited.
The Institute of Cancer Research (ICR) is one of the world’s most influential cancer research institutes.
Scientists and clinicians at the ICR are working every day to make a real impact on cancer patients’ lives. Through its unique partnership with The Royal Marsden Hospital and ‘bench-to-bedside’ approach, the ICR is able to create and deliver results in a way that other institutions cannot. Together the two organisations are rated in the top four cancer centres globally.
The ICR has an outstanding record of achievement dating back more than 100 years. It provided the first convincing evidence that DNA damage is the basic cause of cancer, laying the foundation for the now universally accepted idea that cancer is a genetic disease. Today it leads the world at isolating cancer-related genes and discovering new targeted drugs for personalised cancer treatment.
As a college of the University of London, the ICR provides postgraduate higher education of international distinction. It has charitable status and relies on support from partner organisations, charities and the general public.
The ICR’s mission is to make the discoveries that defeat cancer. For more information visit www.icr.ac.uk
The Chris Lucas Trust
The Chris Lucas Trust is a UK charity which was set up in March 2001 by Lynn and Lynn Lucas following the tragic death of their son Christopher from rhabdomyosarcoma. The Trust raises funds to continue the vital work of a senior post doctoral scientist who focuses exclusively on rhabdomyosarcoma. The research position, which the Trust has funded exclusively since 2005, is based at The Royal Marsden Hospital NHS Foundation Trust and The Institute of Cancer Research.