Personalized Blood Test Can Detect Persistent Lung Cancer

By LabMedica International staff writers
Posted on 21 Mar 2022

Image: Personalized blood test for cancer patients (Photo courtesy of University of Cambridge)

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 tumor, but scans cannot pick up tiny quantities of cancer cells known as minimal residual disease (MRD) which could still regrow into further tumors. Patients who are at a higher risk of their lung cancer returning can now be identified by a personalized blood test that is performed after treatment.

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, according to results from a study by researchers at the University of Cambridge (Cambridge, UK) and Inivata (Cambridge, UK), a biotech company. The Lung Cancer Circulating Tumour DNA (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, developed by Inivata which analyses up to 48 different mutations that are unique to each patient’s tumor.

To find out if liquid biopsy could find lung cancer patients with MRD, the LUCID-DNA study team enrolled 88 patients who were treated for early stage non-small cell lung cancer. This type of cancer accounts for over 85% of all lung cancer cases. The research team extracted DNA from tumor 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 personalized to the patient’s tumor. The liquid biopsies were then used to detect tumor DNA in blood samples collected before treatment, and for up to nine months after treatment. The researchers found that patients who had tumor 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.

“If cancer cells remain in the body after treatment a tumor can regrow. If that happens, it is a big setback for patients and the doctors treating them,” said Dr. Nitzan Rosenfeld, group leader at the Cancer Research UK Cambridge Institute, Chief Scientific Officer of Inivata and co-lead author of the study. “Liquid biopsy can be used to detect tiny amounts of residual cancer after treatment, flagging those patients who have signs that their tumor may not have been eradicated completely with treatment. We’re hoping that this technology could help doctors decide when additional rounds of treatment are needed, and could save lives.”

“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,” said Professor Robert Rintoul, Professor of Thoracic Oncology at the University of Cambridge, Honorary Respiratory Physician at Royal Papworth Hospital and co-lead author of the study. “Being able to offer patients personalized monitoring and treatment will ultimately save more lives and help us to beat cancer sooner.”

Related Links:
University of Cambridge
Inivata