‘Liquid biopsies’ could help spot genetic faults in lung cancer

In collaboration with the Press Association

Blood samples could offer an alternative to tumour biopsies in lung cancer patients, according to European researchers.

"This research adds to the growing evidence that getting tumour DNA from blood samples could be a reliable way to identify important genetic faults in lung cancer patients."- Dr. Dana Tsui, Cancer Research UK's Cambridge Institute

Experts believe the findings could aid future research by overcoming the difficulty of accessing some tumour samples.

The researchers analysed blood samples from patients with advanced non-small-cell lung cancer and looked for ‘circulating free DNA’ – bits of DNA shed from tumour cells that can be isolated from the blood.

They found that the tumour DNA present in blood samples could be used to identify different types of tumour-causing genetic faults in a gene called EGFR.  

The study, published in the journal JAMA Oncology, analysed blood samples from 97 patients who took part in the EURTAC clinical trial. And in 78 per cent of the blood samples tested, two important genetic faults were successfully identified.

Dr Dana Tsui, cancer genetics scientist at Cancer Research UK’s Cambridge Institute, said: “This important study shows the potential of ‘liquid biopsies’ in opening up new research opportunities - when previously it’s been difficult to get tumour samples from patients. This research adds to the growing evidence that getting tumour DNA from blood samples could be a reliable way to identify important genetic faults in lung cancer patients.

“The study also looks at the effect  of different genetic faults within the EGFR molecule on patient survival - something that’s been difficult to answer before the development of this technology,” explained Tsui.

They found that the presence of a particular fault in EGFR found in DNA isolated from blood – called L858R – was linked to poorer survival than the second fault analysed in the study.

The researchers believe their findings raise the question of whether the tumour DNA present in blood samples could offer a less invasive way of searching for key genetic faults in the future.

 

References

  • Karachaliou N. et al. (2015). Association of EGFR L858R Mutation in Circulating Free DNA With Survival in the EURTAC Trial, JAMA Oncology, DOI:10.1001/jamaoncol.2014.257