Speaker's Highlight

• Don Sin University of British Columbia, St. Paul Hospital (Canada)
  Kenneth R. Chapman Toronto General Hospital Research Institute (Canada)
• Parameswaran Nair McMaster University (Canada)
  Carolyn Calfee UCSF (U.S.A.)
• Gregory P. Downey University of Colorado School of Medicine (U.S.A.)
  David A. Schwartz University of Colorado School of Medicine (U.S.A.)
• Neil Schluger Tuberculosis Control Branch, California Department of Public Health (U.S.A.)
  Nick Kim Critical Care & Sleep Medicine, University of California San Diego (U.S.A.)
• Nicola Hananiah Baylor College of Medicine (U.S.A.)
  Jae-Joon Yim Seoul National University College of Medicine (Republic of Korea)
• Koichiro Asano Tokai University School of Medicine (Japan)
  Diahn-Warng Perng Taipei Veterans General Hospital (Taiwan)
• Konstantinos Kostikas University of Ioannina (Greece)
  Karin Klooster University Medical Center Groningen (Kingdom of the Netherlands)

• How Low-Dose CT Screening Can Reduce Lung Cancer Deaths

  Lung cancer remains one of Australia’s most serious cancer health problems, particularly among people with a long history of smoking. Symptoms often appear after the disease has reached an advanced stage, when surgery may no longer be possible and treatment becomes more complex. Screening aims to find cancer earlier, when it is more likely to be treatable.

  Low-dose computed tomography, commonly called LDCT, creates detailed images of the lungs using less radiation than a standard diagnostic CT scan. For carefully selected smokers and former smokers, regular scans can identify small lung nodules before symptoms develop. The purpose is not to scan everyone, but to focus resources on people with the greatest risk.

  Evidence from large international trials indicates that LDCT screening can lower lung cancer mortality in high-risk groups. The National Lung Screening Trial in the United States reported a reduction of about 20% in lung cancer deaths, while the European NELSON trial found a comparable benefit, particularly among men and people with substantial smoking exposure.

  Australia is adapting this evidence to local healthcare conditions. The National Lung Cancer Screening Program, introduced in 2025, uses eligibility criteria based on age and smoking history. Its success will depend on reliable follow-up, equitable access through Medicare and public hospitals, and clear communication with communities across Sydney, Melbourne, Brisbane, regional centres and remote areas.

  How Low-Dose CT Detects Lung Cancer Earlier

  A low-dose CT scan can reveal small abnormalities that may be invisible on a chest X-ray. Detecting a tumour at stage one or two can expand treatment options, including minimally invasive surgery, stereotactic radiotherapy and targeted therapies. Earlier diagnosis is closely associated with better survival because the cancer is less likely to have spread.

  Screening scans may identify nodules that are benign, scar-related or caused by infection. This means an abnormal result is not the same as a cancer diagnosis. Radiologists usually assess the nodule’s size, shape and growth over time, with repeat imaging or specialist review used when appropriate.

  What Mortality Research Shows

  The strongest evidence comes from randomised trials comparing regular LDCT with usual care or chest radiography. Participants generally had a heavy smoking history and were within an age range where lung cancer risk was high. The reduction in mortality emerged over several years, reinforcing that screening works as a continuing program rather than a single scan.

  Australian modelling suggests that a well-targeted national program could prevent deaths while avoiding the much larger number of unnecessary scans that would result from screening people at low risk. The benefit depends on participation, scan quality, timely diagnosis and access to treatment. A delayed referral can reduce the advantage gained from early detection.

  Balancing Benefits With Possible Harms

  False-positive results are a central concern. A suspicious nodule may lead to repeat CT scans, specialist appointments, biopsies or surgery, even when no cancer is present. Modern assessment protocols reduce this risk by using nodule measurement, growth rates and structured reporting instead of immediately treating every finding as malignant.

  Radiation exposure from an LDCT scan is low, but it is not zero. Repeated scans therefore need a clear clinical justification. Screening can also create anxiety, particularly while a person waits for a follow-up result. A balanced discussion should explain both the potential mortality benefit and the possibility of further investigations.

  Who Is Most Likely to Benefit in Australia

  The Australian program is designed for people aged 50 to 70 who have smoked at least 30 pack-years and currently smoke or stopped within the previous decade. A pack-year represents smoking 20 cigarettes a day for one year. Eligibility rules and referral pathways should be checked through current Australian Government and state or territory health information because program details can change.

  Access may look different in a major city and in a remote community. Someone in Melbourne or Sydney may have several imaging providers nearby, while a person in regional Queensland, Western Australia or the Northern Territory may face travel, workforce and appointment barriers. Aboriginal and Torres Strait Islander communities also need culturally safe communication and screening pathways that reflect local healthcare priorities.

  How Screening Fits Into Smoking Cessation

  A screening appointment is an important opportunity to support quitting, but it must never imply that screening makes continued smoking safe. Stopping smoking remains the most effective way to reduce future lung cancer risk and improves heart, vascular and respiratory health at any age.

  Clinicians can combine LDCT referrals with nicotine replacement therapy, prescription medicines, counselling and Quitline services. Australian smokers may access Quitline support through their state or territory, including telephone-based assistance that can be useful for people who live far from respiratory clinics.

  Making Results Clinically Useful

  The mortality benefit of screening relies on an organised pathway from eligibility assessment to treatment. Reports should reach the referring clinician quickly, abnormal findings should trigger a documented follow-up plan, and patients should know who will contact them. Multidisciplinary teams may include respiratory physicians, radiologists, thoracic surgeons, oncologists, nurses and smoking-cessation specialists.

  Several practical measures can strengthen the program:

  • Confirm smoking history in pack-years, including the date smoking stopped.
  • Use accredited imaging services with low-dose protocols and experienced thoracic radiologists.
  • Explain before scanning that a nodule may require monitoring without being cancer.
  • Record every abnormal result and arrange follow-up within the recommended timeframe.
  • Link screening appointments with evidence-based smoking-cessation support.
  • Provide culturally appropriate information and transport assistance where needed.
  • Monitor participation and outcomes across metropolitan, regional, rural and remote Australia.

  Equity, Trust And Long-Term Outcomes

  A national screening program will be judged by more than its mortality statistics. Participation may be lower among people experiencing financial stress, unstable housing, limited transport, language barriers or distrust of healthcare institutions. Outreach through general practices, Aboriginal Community Controlled Health Services and community health organisations can help make screening more accessible.

  Trust also depends on explaining why a person qualifies, what the scan can and cannot show, and what happens after an abnormal result. Clear information is especially important for people who fear that a cancer diagnosis will lead to stigma because of their smoking history. Respectful care can improve engagement without minimising the risks of tobacco use.

  For eligible smokers and recent former smokers, LDCT offers a meaningful chance to detect lung cancer before it becomes difficult to treat. In Australia, its greatest impact will come when accurate scanning is paired with prompt follow-up, smoking cessation and practical support across every part of the health system. The essential takeaway is simple: people who meet the eligibility criteria should discuss organised low-dose CT screening with a qualified Australian healthcare professional and keep every recommended follow-up appointment.

  Richard Russell Nuffield Department of Clinical Medicine, University of Oxford (United Kingdom)
• Mona Bafadhel King’s College London (United Kingdom)
  David Jackson Guy’s and St Thomas’ Hospital, King’s College London (United Kingdom)
• James Chalmers University of Dundee (United Kingdom)
  David Price University of Aberdeen (United Kingdom)