Scientists at the Cancer Research UK Cambridge Institute used a personalised blood test for patients, which is a type of liquid biopsy that can pick up tiny fragments of DNA that are released into the blood as tumours grow. This DNA, called circulating tumour DNA (ctDNA), can reveal the state of the tumour, its location and potentially its weaknesses, which could be used to select the best treatments.
The results from the Lung Cancer Circulating Tumour DNA (LUCID-DNA) study, funded by Cancer Research UK, have been published today (Thursday 17 March) in the Annals of Oncology.
Many patients who are treated for early-stage non-small cell lung cancer can be cured with either surgery, radiotherapy or sometimes (chemo)radiotherapy.
After treatment, lung cancer patients are carefully followed up with tests including CT scans to find out if the treatment has removed the tumour, but scans won’t pick up tiny quantities of cancer cells known as minimal residual disease (MRD) which could still regrow into further tumours.
By finding signs that lung cancer cells might still be present and active after treatment, using methods such a liquid biopsy, doctors might be able make better choices about treating patients, aiming to improve the chances of survival for patients who are at higher risk while reducing side effects for patients who are at a lower risk group.
The LUCID-DNA study aimed to find out if circulating DNA can be detected in early stage lung cancers. It used a liquid biopsy, called RaDaR™, which analyses up to 48 different mutations that are unique to each patient’s tumour. RaDaR™ was developed by Inivata, a biotech company co-founded by Dr Rosenfeld, and is based on technologies developed initially by his lab at the Cancer Research UK Cambridge Institute.
Dr Nitzan Rosenfeld, group leader at the Cancer Research UK Cambridge Institute, Chief Scientific Officer of Inivata and co-lead author of the study, said: “If cancer cells remain in the body after treatment a tumour can regrow. If that happens, it is a big setback for patients and the doctors treating them.
To find out if liquid biopsy could find lung cancer patients with MRD, the LUCID-DNA study team enrolled 88 patients who were treated at Royal Papworth Hospital and Addenbrooke’s Hospital for early stage non-small cell lung cancer (NSCLC). NSCLC accounts for over 85% of all lung cancer cases.
The research team extracted DNA from tumour samples provided by the patients and sequenced the DNA to find combinations of mutations unique to each patient’s lung cancer. Using this genetic “fingerprint”, Inivata created a blood test which was personalised to the patient’s tumour.
The liquid biopsies were then used to detect tumour DNA in blood samples collected before treatment, and for up to 9 months after treatment. The researchers found that patients who had tumour DNA present between two weeks and four months after treatment were much more likely to have their lung cancer come back or to die from it.
Professor Robert Rintoul, Professor of Thoracic Oncology at the University of Cambridge, Honorary Respiratory Physician at Royal Papworth Hospital, co-lead of our Thoracic Cancer Programme and co-lead author of the study, commented: “We need to study these liquid biopsies further to find the best ways to deploy them, but these results clearly show that they can potentially be an effective tool to help decide which patients need further treatment.
Lung cancer is the third most common type of cancer in the UK. Every year, around 48,500 people are diagnosed with lung cancer and every year around 35,100 people die from the disease in the UK.
Aart Alders participated in the Lung Cancer Circulating Tumour DNA (LUCID-DNA) observational clinical study at Royal Papworth Hospital following his lung cancer surgery.
“I was first diagnosed with an early-stage lung cancer about five years ago and underwent a surgical operation to remove it,” he said. “Although some people need further treatment with chemotherapy, I have been very fortunate and my original lung cancer has not returned.
Michelle Mitchell, Chief Executive of Cancer Research UK, said: “Lung cancer is one of the biggest killers in the UK. The earlier it is caught, the more likely it is to be treated successfully.
“Detecting signs of cancer before or after treatment without the need for invasive surgery has huge potential for both patients and doctors.
“I look forward to seeing more research that will develop liquid biopsy further, which will and ultimately make it much easier for doctors to offer treatment that best matches the patient’s needs, increasing their chance of survival.”