Lung cancer is one of Australia’s biggest killers, with the highest mortality rate of any cancer in the country and a low five-year survival rate. This is partly because lung cancer is often not detected until it’s too late for treatment to be effective.
However, if caught early, most types of lung cancer are treatable – which is the main reason 17% of Australians diagnosed with lung cancer are alive five years later and survival is slowly improving. So why don’t we have a screening program for lung cancer? And how close are we to developing one? The short answers to these are 1) it’s complicated, cost and potential harm for patients are the major hurdles, and 2) we’re getting closer. Read on as we unpack these in more detail.
Barriers to lung screening
Currently, only breast, bowel, and cervical cancers have national cancer screening programs in Australia, and no country has nationwide screening for lung cancer. Encouragingly, these programs were all preceded by government-funded feasibility studies. Which is where lung cancer is currently sitting, with the Australian Minister for Health, Greg Hunt, commissioning a review in August this year.
On current evidence, low-dose CT scans for long-term smokers and ex-smokers are the most likely path towards targeted lung cancer screening. But there are a few unresolved issues that need to be closely examined. These include:
A potential high rate of “false positives” – finding nodules (small, non-specific growths on the lung) that may never pose a risk to the patient
Added risk from subsequent investigation, such as unnecessary but potentially harmful radiation from scans and unnecessary invasive treatment following a false-positive test
Flow-on out-of-pocket costs for the patient for procedures that may not be beneficial
A lack of consensus around the definition of a positive test and how they should be followed up
Uncertainty regarding the best target population and how often they should be screened
Uncertainty regarding cost and extra load on the health system
Uncertainty around how to implement a risk-based screening program and targeting it to people most likely to benefit.
How close are we?
As you can see, implementing a national lung cancer screening program in Australia is not a simple matter. There are many elements to consider, but we are closer than ever.
The evidence is strengthening worldwide. The landmark NELSON study of almost 8000 heavy smokers and ex-smokers in the Netherlands and Belgium has shown a CT-based organised screening program can save lives. The National Lung Screening Trial in the US showed similar results.
However, these are trials. The challenge is implementation – translating trial results into a health system, with certainty that it will deliver more benefits than harms and in a way that is cost-effective, so government could offer screening free, like it does for bowel, cervical and breast cancers.
Cancer Council NSW has been leading the research into targeted lung cancer screening from the not-for-profit sector in Australia. Recently, this includes an analysis into the cost-effectiveness of a national lung screening program and a study validating a simple algorithm that can predict the likelihood of lung cancer in smokers and ex-smokers. As the evidence strengthens, so too will our engagement with government and the community. Minister Hunt’s commitment to reviewing the evidence, as part of a national strategy to improve cancer screening outcomes, is a potential game-changer.
Lung cancer screening is a great opportunity to save thousands of Australian lives but there are still many questions left to answer. Targeted research is helping us find the answers and should lead to more cost-effective, systematic ways to finding lung cancer early in people with increased risk.