Blood test may soon be able to detect aggressive lung cancer

Australian researchers have discovered a unique molecular signature in the blood that could be used to help treat patients living with an aggressive form of lung cancer, who are most likely to respond to immunotherapies.

The Melbourne research team from the Walter and Eliza Hall Institute identified a possible blood biomarker produced by the deadly disease, raising hope of an early detection test.

Lung cancer is the biggest cancer killer in Australia, claiming the lives of 9,021 people last year. It’s also one of the most commonly-diagnosed cancers in the country, with some 12,434 new cases being recorded in 2017.

Early trials on mice have revealed the unique molecular signature in the blood that one day may be able to pick up the more aggressive forms of cancer with a blood test. The research was published in the Cell Metabolism Journal.

The study focused on the KEAP1/NRF2 and P13K signalling pathways, which are commonly found in human lung cancers known as adenocarcinomas. 

“More than one in five lung cancer adenocarcinomas have alterations in the KEAP1/NRF2 pathway, suggesting it is a major cancer driver,” Dr Sutherland said. “These cancers are very aggressive, are resistant to standard therapies and have a poor prognosis, so new therapies are urgently needed.”

The study found that 50 per cent of lung cancers are adenocarcinoma — a type of cancer that’s usually associated with a history of smoking, but is also the most commonly diagnosed lung cancer in non-smokers. It’s also more common for women and younger lung cancer patients.

The researchers also found tumours from this type of lung cancer had specific characteristics that were highly likely to respond well to immunotherapy.

“This is extremely important because these tumours are chemotherapy and radiotherapy resistant, meaning there are effectively no current treatments for these patients,” Dr Best said. “Using preclinical models, we showed for the first time that tumours have the ‘markers’ that respond to anti-PD-1 and anti-CTLA-4 immunotherapies, which are some of the most exciting new cancer therapies being investigated in the clinic.”

She added that the trials were promising because they showed the immunotherapies were working.

The research was also one of the first in the world to show that signalling caused by mutations in the KEAP1/NRF2 and P13K pathways resulted in the development of adenocarcinomas.

“Our hope would be that the test could identify patients likely to respond to immunotherapies, but also that it could be a simple, non-invasive blood test for the early detection of these lung cancers,” Dr Sutherland said. “The next steps would be to analyse human samples to prove the same is true in lung adenocarcinoma patients, but we need more funding for that work to continue and to generate results that will lead to better detection and treatments for the community.”

Have you been impacted by lung cancer? Did you know lung cancer was the leading cancer killer in Australia?