Blood test developed to test for lung cancer

A blood test could be used to detect the early signs of lung cancer, according to a new study.

At present, patients undergo invasive procedures, like biopsies, as part of follow-up tests when lesions show on CT (computerised tomography) scans.

But the procedures are often unnecessary because the scans have a high failure rate for correctly detecting the disease.

Now researchers in the United States have found that people suffering from lung cancer have higher levels of four proteins in the blood than those without it.

They compared the levels of these proteins in the blood of nearly 100 lung cancer sufferers to the levels of nearly 100 people without the disease and were able to detect the illness with 80% accuracy.

The results of the study will be published next week in the Journal of Clinical Oncology.

Lead study investigator Edward Patz Jr, a radiologist at Duke University Medical Centre, said: “CT scans have a very high false positive rate when trying to discover lung cancer.

“What that leads to is several follow-up imaging studies or invasive procedures like biopsy, which have risks of their own.

“This study is the first step in developing a test that would allow us to sample a patient’s blood and determine whether more invasive testing and treatment are necessary.”

A recent study found that suspicious lumps were detected by CT scans in more than 70% of those screened, while lung cancer was found in less than 3%.

Mr Patz said: “We talk about how devastating this disease is all the time, but we still don’t have a screening system in place that can detect lung cancer early, without exposing patients to the risks of biopsy and surgery.

“This study is an important step in the right direction.”

The ultimate aim, say researchers, is to develop a screening system by which patients have a blood test before X-rays and those found to be at high risk have a CT scan for further evaluation.

About 40,000 people in the UK die every year from lung cancer. It is the most common form of the disease and the most common cause of death from cancer in both men and women, although it affects more men than women.

Responding to the study today, Cancer Research UK senior health information health officer Ed Yong said: “This is one of many blood tests that are being investigated for the early detection of lung cancer.

“These tests have the potential to save many lives, but research in this area is at a very early stage. Much more work is needed to discover if these tests could be successfully used in the diagnosis of patients.”