Genetic test helps optimise cancer treatment
4 December 2013
Testing a tumour for certain genes could help decide whether the patient would benefit from receiving additional drugs with a radiotherapy programme, according to a study by the Manchester Cancer Research Centre.
Tumours with hypoxia — low levels of oxygen — often respond less well to radiation therapy. There are several agents that can be given to patients before radiotherapy to reduce hypoxia, but these are not given as standard. Being able to measure hypoxia in a tumour is would give doctors a valuable way of identifying which patients might benefit from treatment with hypoxia reducing agents before radiotherapy.
The Manchester researchers have developed a genetic profile for tumours that should indicate the overall level of hypoxia. They gave cancer patents two agents which in combination are known to increase oxygenation: nicotinamide and carbogen, followed by radiotherapy and compared the radiotherapy without the agents.
For laryngeal tumours, those classed as more hypoxic saw a significant benefit from receiving additional agents as well as radiation therapy. However, in bladder cancer, patients with more hypoxic tumours did not benefit from adding extra agents.
The team tested patients’ tumour samples for 26 genes in order to classify them as more or less hypoxic, and then analysed whether this hypoxia score related to the results of treatment.
“Our goal is to find ways of predicting how patients will respond to different treatments. Future cancer treatments will be personalised so that patients get the best therapy for their tumour.” said Professor Catharine West, who led the research. “Personalising therapy will not only increase the number of people surviving cancer but also decrease side-effects, as patients would be spared from having treatments that are unlikely to work in their tumour.”
Professor West added: “We will now test how the hypoxia score works in the clinic in a trial starting in December in patients with head and neck cancer. I have studied ways of measuring hypoxia in tumours for many years so this is a very exciting finding that could help us optimise how we use radiotherapy to get the best outcome for patients.”
A 26-gene hypoxia signature predicts benefit from
hypoxia-modifying therapy in laryngeal cancer but not bladder
cancer. Clinical Cancer Research 1 September 2013, 19(17): 4879-88.
doi: 10.1158/1078-0432. CCR-13-0542. "