Call for new trials as cancer genomics comes of age
It is time to bring cancer genomics from the lab bench into large-scale clinical trials, a leading Cancer Research UK scientist will tell delegates at the charity's Senior Researchers Meeting in Harrogate today.
Professor Patrick Johnston is one of a number of pioneering scientists exploring how intimate genetic knowledge from individual tumours could help doctors predict which treatments will benefit their patients best. Major trials of this approach - which has shown considerable success in the lab - are needed to test its full predictive potential.
Progress towards this goal has been too slow to date, according to Professor Johnston. He believes that large-scale trials could lead to a paradigm shift in the way doctors approach treating their patients, as well as providing new medical facilities to enable this complex but potentially revolutionary area of research to reach cancer patients across the UK.
Tumours are often resistant to individual chemotherapy drugs. Identifying patients who are not likely to benefit from a particular treatment would enable doctors to pursue other lines of treatment - freeing patients of the side effects of drugs that are unlikely to help them and improving their chances of survival.
Genomics allows scientists to obtain the detailed genetic 'fingerprints' of tumours. These fingerprints group tumours into specific types with much greater accuracy than is possible using traditional features such as tumour size, location and cellular make-up - and make it possible to predict which type of treatment will be most potent against them.
Professor Johnston, who is Director of the Centre for Cancer Research at Queens University Belfast and Belfast City Hospital, says: "Cancer genomics could really change the way doctors treat cancer.
"But turning that hope into reality will require a bold acceleration in clinical research. Using genomics in treating cancer is new, and potentially very expensive. Clinical trials will tell scientists and doctors how accurately the use of genomics can target treatments to patients, and confirm whether it is safe and cost-effective.
"Clinical trials for cancer are still very much focussed on testing new drugs. We believe an integrated approach to treatment using detailed genetic information about tumours and patients needs to become a priority."
One barrier to targeting treatment in this way is the risk of false negatives - meaning that patients could be selected not to receive a drug that they actually needed.
Dr Richard Sullivan, Cancer Research UK's Head of Clinical Programmes, says: "Cancer doctors know that many of the drugs they use will only benefit some patients - but they have no clear way of knowing which ones.
"Well-run clinical trials integrating genetic technologies could lead to predictive tests to make treatment a more exact science.
"This will require linking genetic information from patients' tissue samples to high quality data on whether or not they benefit from the treatment, and for how long that benefit lasts."
The specialised equipment and expertise required to uncover a tumour's genetic fingerprint mean that trials will be expensive to run. But scientists believe the end result could be hugely improved efficiency in the prescribing of cancer treatments, improved survival and a large reduction in the number of patients who are over treated.
Professor Johnston adds: "Research has already yielded a large selection of treatments for cancer. The challenge before us now is to find ways to use this growing arsenal effectively."
"This means demonstrating the true clinical value of the tests we have developed in the lab through large-scale clinical trials. Otherwise the full potential of this research may never be realised."
Professor Robert Souhami, Cancer Research UK's Director of Clinical and External Affairs, says: "Professor Johnston is one of a number of Cancer Research UK researchers looking for genetic and other markers that can predict the best treatment for an individual patient's cancer.
"We actively encourage and support research aimed at turning this technology into a clinical reality.
"Many institutions do not yet have the expertise or the equipment needed to run clinical trials involving complex genetic tests on large numbers of samples. Cancer Research UK has set up a specialised funding route to ease the way for scientists and doctors setting up appropriate trials in this exciting area of research."