The National Lung Cancer Screening Program
Australia’s National Lung Cancer Screening Program is now underway, and increasing numbers of low-dose lung CT scans are being performed.
For most people, the lung cancer screening scan itself is straightforward, and the below figure gives a quick oversight of the entire lung cancer screening and assessment pathway. What is less well understood is what happens after a lung CT scan in:
- Scan assessment and reporting,
- Results and management, and
- Results and reminders
The Result: How Lung CT Scans are Reported
Each scan is reviewed by a radiology team and assigned a risk category in the newly developed lung nodule criteria.
This report is sent to the requesting clinician, usually a GP, and recorded in the National Cancer Screening Register (NCSR).
From here, the pathway depends on the level of risk associated with any findings, which determines whether the next step is referral to a specialist or surveillance. The term ‘lung nodule’ may be used.
What is a Lung Nodule?
A lung nodule is a a small, roundish growth of tissue in the lung that appears as a white spot or shadow seen on a lung CT scan. Lung nodules are common and are usually caused by scar tissue, a previous and healed infection that may never have made you sick, or some irritant in the air. More than 90% of nodules are not cancerous (benign), but some require follow-up to assess whether they change over time, or a nodule may be an early lung cancer. Lung nodules are categorised according to risk using criteria and follow up actions that were developed as part of the Australian National Lung Cancer Screening Program. The categorisation is similar to criteria used in lung cancer screening programs in other countries.
If the nodule is low or intermediate risk (Categories 1–4)
- Most lung nodules fall into this group.
- These are managed by GPs or the primary healthcare provider with follow-up chest CT scans at certain time intervals. Depending on the category, this may involve repeat scans at 3, 6 or 12 months to assess if the nodule is changing. This is a way to see if the risk of the lung nodule becoming cancer is getting higher.
- Most of these nodules do not progress to lung cancer, but if it does, it will be detected early when treatment that is aimed to cure lung cancer is still possible.
If the nodule is higher risk (Categories 5–6)
- For higher-risk nodules, the report recommends referral to a respiratory physician or specialist service for further assessment.
- A higher-risk result does not mean a cancer diagnosis is certain.
- Categories 5 and 6 indicate a higher likelihood of malignancy, but some nodules will still be benign after investigation. This is expected in screening programs, where the aim is to detect cancer early while it is more treatable.
- Even if a lung nodule is cancerous, it has still been detected at a much earlier stage than most lung cancers have been found hisotrically, and treatment is likely to eradicate the cancer.
Rapid Access Lung Clinics
Many hospitals now use rapid access nodule clinics to manage referrals to their specialists to ensure everybody is assessed and the highest risk cases are prioritised.
The rapid access clinics generally review scans and clinical information within 24–48 hours, and reduce delays and back and forth communication between GPs and specialists. While patients may not always be contacted immediately if the case is not considered high risk, these nodule clinics provide early patient contact and a way to access inforation when many people may be feeling scared or anxious. Experience from Australia and internationally suggests this improves patient experience and supports timely care.
Rapid access clinics also help meet the early timeframe in the Lung Cancer Optimal Care Pathway, where access to specialist assessment is expected within around 14 days of referral.
If there is no rapid access clinic
Where these clinics are not in place, referral is made by the GP directly to a respiratory physician.
Once your referral is received, the specialist team will review your information. They may request additional scans or details before making an appointment. Waiting times can vary depending on how urgent your situation is.
Further tests and specialist review
If a nodule requires investigation, this may include PET imaging, biopsy, and lung function testing.
If a biopsy is needed, your specialist will recommend the approach that is most likely to provide an accurate diagnosis while minimising risk. The choice depends on the size and location of the lung nodule, your lung function and overall health.
Some nodules are best sampled using a CT-guided needle biopsy through the chest wall. Others can be reached using bronchoscopy, where a thin camera is passed through the airways into the lungs. Modern technologies, including robotic bronchoscopy, allow specialists to reach smaller nodules deeper within the lung than was previously possible. Some people may also require endobronchial ultrasound (EBUS) to sample nearby lymph nodes, or surgery if this is the most appropriate option.
At this stage, care is managed by certain specialists and nurses according to the particular hospital care pathway. Your physician will discuss which approach is most appropriate for your situation.
If these investigations do determine that the nodule is cancerous, it is important to remember that the cancer has been found early when treatment is most effective. One reason lung cancer has had such poor survival in the past is because these early stage lung cancers are usually only detected in a screening program. So participation in a screening program gives you the best possible chance of defeating lung cancer.
Multidisciplinary team (MDT) discussion
If lung cancer is suspected or confirmed, the case is discussed at a multidisciplinary team meeting (MDM). These meetings are common hospital meetings in all different disease areas where diverse expertise is thought to give the best possible outcome.
The lung MDM brings together respiratory physicians, radiologists, surgeons and oncologists to agree on diagnosis, staging and treatment. Discussion of cases at an MDM where treatment may involve multiple specialists has been shown to give better outcomes (1).
When detected early, lung cancer can be cured, but treatment may involve surgery, radiotherapy, chemotherapy, immunotherapy or targeted therapies.
More information on treatment can be found on our ‘What is lung cancer?’ page.
A Changing Pathway
Before lung cancer screening, lung nodules were often incidental findings. With screening, nodules are identified more frequently and require structured follow-up over time. This has introduced a new area of care that sits between primary care (GP) and specialist services.
In response, services are adapting. GPs or other referrers manage surveillance for lower-risk nodules, while rapid access clinics are increasingly used to triage higher-risk findings.
The Thoracic Oncology Group of Australasia (TOGA) is closely involved in supporting the implementation of screening and the translation of evidence into care. As screening evolves, understanding how these pathways function in practice will be an important focus for clinicians and services.
In Summary:
After a lung CT scan:
- the radiologist assigns a risk category and recommendation
- lower-risk nodules are followed up over time
- higher-risk nodules are referred for specialist assessment
- many centres use rapid access clinics to triage referrals
- selected cases proceed to multidisciplinary discussion
References
- Stone, E. et al. (2018) ‘Does presentation at multidisciplinary team meetings improve lung cancer
survival? Findings from a consecutive cohort study’. Lung Cancer; 124:199 https://doi.org/10.1016/j.lungcan.2018.07.032
