A targeted lung cancer screening program is predicted to prevent 12,000 deaths and deliver a gain of 30,000-50,000 QALYs in its first ten years.
The survival benefits of the program, as outlined in a Cancer Australia report on lung cancer screening, are based on evidence that screening will inevitably lead to detection of lung cancers at an earlier, more manageable stage.
The report, which has been delivered to the Federal Health Minister Greg Hunt, said at least 42% of lung cancers were currently diagnosed at stage IV.
The proposed program would comprise biennial low-dose CT screening for current and former smokers aged 55-74 years, or 50-74 years for Indigenous Australians, who also meet a minimum risk threshold.
The report recommends a Prostate, Lung, Colorectal, and Ovarian Cancer (PCLOm2012) risk score of ≥1.51% over six years for eligibility to screening.
Multiple entry points into the program include self-referral, on advice from a health professional, following opportunistic risk assessment screening, or via a more formal invitation from health services or health professionals.
Respiratory physicians would have a role in participant recruitment to the program, alongside GPs, Indigenous health services, primary care nurses, and smoking cessation counsellors.
The program incorporates smoking cessation as a component in the screening and assessment pathway.
“It is proposed that smokers entering the program be offered access to smoking cessation education,” the report said.
“Evidence indicates that compared to an expected general population unassisted quit rate of 3-7% per year, participants in screening trials have shown quit rates of 14-16% at one year follow up, and as high as 24-29% at 5-9 years.”
The program would sit as a national program alongside current breast, cervical and bowel cancer screening programs.
The direct program costs were estimated at $43.5 million in 2021, reducing to $20.8 million in 2024. This excludes the costs of risk assessments within primary care consultations and CT costs covered by existing MBS items and subsequent treatment costs for cancers detected.
The report found the program would be cost effective with an incremental cost-effectiveness ratio of $83,545 per QALY gained.
A huge step forward
Commenting on the report, Professor Fraser Brims said the Cancer Australia report was “comprehensive” and “ambitious” and represented “a huge step forward for Australians at risk of lung cancer”.
Professor Brims, from the Sir Charles Gairdner Hospital and Curtin University, told the limbic there was a good amount of support for the program and optimism that it was time for a change regarding lung cancer.
“My understanding is that Greg Hunt has now taken this to treasury and at some point, it may even be in the next budget, we will hopefully hear something. I think it would be hugely disappointing if there were a long delay,” he said.
“Every time you delay by a year is another 8-10,000 lives lost and that’s just not acceptable really to carry on waiting when we know there is an intervention which can significantly change the outcome of lung cancer across Australia.”
Professor Brims, an investigator on the International Lung Screening Trial (ILST), said the trial would be delivering results over the next three to four years.
“My sense of this [proposed screening program] is that it is going to be an initial implementation model and that it is agile, in so much as it will adapt to important new evidence as it becomes available.”
For example, it was possible that the adoption of occupational exposure into the risk modelling, or indeed increasing the target age group might be considered in the future.
“The data is clear. Unequivocally there is a very strong benefit for screening in a target high risk population. You just have to select the population very carefully,” he said.
Professor Brims said implementation will be complex and many health professions would feel the impact.
“That said, I get the sense from across the board that people accept that the inequality of outcomes for lung cancer, in terms of clinical support or research funding for years, has been unfair.”
He said surgeons and radiologists were just some who would see an uptick in work.
“The first round will pick up a range of cancers so there will be some more advanced cancers so some of those will end up with oncology.”
“But actually, in terms of the initial diagnostic work-up, the vast majority will come through respiratory. We will have quite an uplift in work, in terms of bronchoscopy, and arranging biopsies and seeing them through to the MDTs.”
“But after the first round, then you are down to small incident cancers and that is where the thoracic surgeons will become a lot more busy because they will be doing the lobectomies and the curative work which is where the big impact will be.”
“If the program is working well, the oncologists won’t see much change then because the lung cancers will be picked up at an early stage.”