Scientists from the Francis Crick Institute, UCL, UCLH and Personalis have found that a test to detect circulating tumour DNA can predict lung cancer outcome in a Cancer Research UK-funded study.
Circulating tumour DNA (ctDNA) is fragments of DNA released into the blood by tumours. It’s known to be important for disease prognosis but can be difficult to measure precisely.
In research published today in Nature Medicine, Crick and UCL scientists worked with Personalis to test a platform called NeXT Personal, which can detect very small amounts – 1 part per million – of ctDNA. This builds on the Crick team’s discovery of signals in the blood that detect cancer cells after treatment, which could indicate a potential for relapse.
They applied the platform to blood plasma samples from 171 people with early-stage lung cancer in the TRACERx cohort, finding that people with a low level of ctDNA before surgery were less likely to relapse and had improved overall survival rates than people with a high level of ctDNA.
The high sensitivity of the test meant that smaller amounts of ctDNA could be detected, which prevented people with a lower amount of ctDNA from being incorrectly labelled ctDNA negative.
Early-stage lung cancer is usually treated by removing the tumour by surgery and with chemotherapy or immunotherapy, depending on the stage of the tumour, which aims to achieve the highest chance of cure.
Credit: The Francis Crick Institute.