A new blood test could help change the way cancer is diagnosed, it has been claimed.
British researchers hope that it might one day be available in GP surgeries to provide a diagnosis within days and the chance of earlier treatment.
The test, which helps to identify cancer-specific gene mutations in the DNA, could be “a real game changer” in the diagnosis and treatment for all types of cancer, according to consultant thoracic surgeon Eric Lim, who led the study on blood tests from 223 patients.
Researchers were not told whether patients, who were all pre-surgery for known or suspected lung cancer, had already received a definitive diagnosis.
Using the blood test, they were able to correctly identify cancer-specific gene mutations in the DNA of nearly seven out of 10 patients who were later confirmed to have cancer.
DNA was extracted from the plasma – the fluid part of the blood – and analysed to identify three common gene mutations.
Cancerous tissue was also analysed for these genetic abnormalities to see how closely it could be linked to the blood sample.
These cancer-specific gene mutations are not usually found in the blood of healthy individuals.
In presenting the findings at the annual World Conference on Lung Cancer in Colorado, US, Lim said: “The test is not an alternative to a biopsy for all patients, but when a blood test shows a positive result, this could mean a patient is saved from going through an unnecessary and invasive diagnostic procedure.
“It might also result in patients having earlier imaging scans and beginning treatment sooner.”
Biopsies, or tissue samples, are often taken with a needle during a CT scan. It can lead to complications for a small number of patients.
The new blood test could be a less invasive but still accurate method for a large number of patients with suspected cancer.
Patients with primary or secondary lung cancer were the focus of the study, which found they shared gene patterns that were common to patients with other forms of cancer, such as colorectal cancer.
It was suggested the blood test could be useful in suggesting the presence of other cancers.
A negative result from the blood test would not completely rule out the presence of cancer cells, Lim added.