Patrick Griffin, 65, was initially referred to a lung specialist for sleep apnoea.

But after meeting test criteria, including being over 50 and an ex-smoker, he was sent to the Australian National Lung Cancer Screening Program for further testing.

There, a CT scan picked up stage 1 lung cancer.

“I was very surprised, again because there were no symptoms,” Griffin said.

Just two weeks later, Griffin underwent surgery at Cabrini Hospital to remove a quarter of his lung.

“I probably wouldn’t have got checked out because I was going along all right, [I’d] given up smoking about 12 months ago,” he said.

In more than half of cases, lung cancer is picked up at stage 4.

Only 16 per cent of lung cancer cases are detected at stage 1, with more than half reaching stage 4 before they are detected.

There’s hope the free screening program could detect as much as 60 per cent of cases, preventing more than 500 deaths every year.

“It’ll fundamentally change the way lung cancer is treated in this country, and it will fundamentally change the outcome for patients,” said Professor Chris Merry, cardiothoracic surgeon at Cabrini Hospital.

Anyone who is between 50 and 70 years old, is a current or former smoker, and isn’t showing any symptoms is eligible for the Medicare-subsidised program.

It’s as easy as getting a referral from your GP.

“This is just changing the paradigm, really to flip the script and make more early stage lung cancers more diagnosable,” lung specialist at Cabrini Hospital Dr Hari Wimaleswaran said.

“It’s an absolute game changer for the patient, their family members, and even us as clinicians to see how impactful this screening program can be, and change the trajectory of their life really.”