Lung Cancer Screening

Lung cancer remains one of the leading causes of cancer-related deaths worldwide. In Singapore, lung cancer affects both men and women, smokers and non-smokers, and is often diagnosed at a later stage because early disease may not cause noticeable symptoms. Lung cancer screening focuses on identifying lung cancer at an earlier, more treatable stage, particularly among individuals at higher risk.

This page explains what lung cancer screening involves, who may benefit, the screening methods used, and how NCCS supports early detection and assessment.

Understanding Lung Cancer Screening

Lung cancer screening refers to medical tests used to detect early signs of lung cancer in individuals who do not have symptoms. The goal is to identify cancer at an early stage, when treatment options may be more effective and to improve health outcomes.

Screening differs from diagnostic testing, which is performed when symptoms such as persistent cough, chest pain or breathlessness are already present. Instead, screening targets individuals who feel well but may have a higher risk of developing lung cancer due to factors such as smoking history or age.

Early detection through screening provides valuable information that helps guide further assessment, monitoring or treatment planning.

Why Early Detection and Assessment Matter

Lung cancer often develops silently. By the time symptoms appear, the disease may already be advanced. Lung cancer screening supports:

• Detection of lung cancer at an earlier stage 
• Improved chances of curative treatment for selected patients 
• More informed decision-making about further investigations or care 
• Timely referral to specialist teams when abnormalities are detected

Early detection does not guarantee cure, but it can significantly influence treatment options and long-term outcomes.

Who Should Consider Lung Cancer Screening in Singapore

Currently, lung cancer screening is not recommended locally for non-smokers. It is most beneficial for individuals (e.g. heavy smokers) who are at higher risk of developing lung cancer.

Individuals Who May Benefit From Screening

Singapore’s January 2025 lung cancer screening guidelines recommend screening for individuals aged 50 to 80 with a 20-pack year* smoking history who currently smoke or have quit within the last 15 years.

*A 20-pack year – a unit used to measure a person’s lifetime smoking history – is equivalent to smoking one pack of cigarettes (of 20 sticks) a day for 20 years, two packs for 10 years, or half a pack for 40 years.

Screening decisions are individualised and should be made in discussion with a healthcare professional, taking into account overall health and personal preferences.

Low-Dose CT (LDCT) for Lung Cancer Screening

Low-dose CT is the only recommended screening test for lung cancer in high-risk individuals internationally. It uses lower levels of radiation than a standard CT scan while providing detailed images of the lungs.

Why LDCT Is Used

LDCT screening has been shown to:

• Detect small lung nodules that may not be visible on chest X-rays 
• Identify lung cancer at an earlier stage 
• Reduce lung cancer mortality in selected high-risk populations

Lung Cancer Screening Study Led by NCCS

Unlike in the West, where majority of lung cancer cases are attributable to smoking, nearly half of Singapore’s lung cancer patients have never smoked.

This is in concordance with the Asia-pacific trend of higher rates of adenocarcinoma, particularly in women and in non-smokers.

To understand the effectiveness of lung cancer screening for the local at-risk and/or high-risk populations, NCCS is leading a lung cancer screening research study called ‘SOLSTICE’ (SingapOre Lung cancer Screening Through Integrating CT with other biomarkErs). SOLSTICE uses LDCT scans to screen for lung cancer early in smokers and non-smokers.

SOLSTICE is run at institutions on the SingHealth Outram Campus, Sengkang General Hospital and Changi General Hospital. Plans are underway to expand to other healthcare clusters in the future.

The study aims to recruit 2,000 smoking and non-smoking individuals:

- Male or female between 50-80 years old
- Singaporean and/or permanent resident of Singapore
- Smoker of 20-pack years or more (currently smoking or quit less than 15 years ago)
- Never smoker or smoked less than 10 pack-years and has quit for at least 15 years, AND has family history of lung cancer within 1st and 2nd degree relatives

What is included in this study:

- Low-dose CT scans
- Blood tests related to lung cancer
- Questionnaires

How to participate:

- Click here to complete a pre-screening questionnaire for eligibility assessment, or
- Email lung.cancer.screening@singhealth.com.sg to find out more about the study

Understanding Lung Cancer Screening Results

Lung cancer screening results can broadly include:

No abnormalities discovered.

If no abnormalities are discovered on the LDCT chest scan, you may consider continuing screening scans until you and your doctor determine they are unlikely to offer a benefit, such as if you develop other serious health problems.

Lung nodule(s) detected.

Lung cancer may appear as a small spot in the lungs. Unfortunately, many other lung conditions look the same, including scars from lung infections and benign growths. Most small nodules do not require immediate action and will be monitored at your next LDCT screening. In some situations, the results may suggest the need for another LDCT in a few months to see if the nodule grows. Growing nodules are more likely to be cancerous.

A large nodule is also more likely to be cancerous. For that reason, your doctor or a lung specialist may recommend additional tests, such as a biopsy, a procedure to remove a piece of a large nodule for laboratory testing, or for additional imaging tests, such as a positron emission tomography (PET) scan.

An abnormal screening result does not automatically mean cancer, but it does require careful evaluation.

Other health problems reported.

Your lung cancer screening test may detect other conditions of the lungs (other than nodules), heart and any adjacent organs that may be common in people of an age group or who have smoked for a long time.

Benefits and Limitations of Lung Cancer Screening

Benefits

• Early detection of lung cancer in high-risk individuals 
• Greater treatment options when cancer is found early 
• Reassurance for individuals with normal results 
• Structured follow-up

Limitations

• Screening may not detect all lung cancers 
• False-positive findings may occur 
• Some detected abnormalities may never become clinically significant 
• Screening involves exposure to low levels of radiation

At NCCS, these benefits and limitations are discussed openly to support informed consent and shared decision-making.

Lung Cancer Screening and Smoking Cessation

Smoking is the most significant risk factor for lung cancer. Lung cancer screening does not replace the importance of smoking cessation.

Screening consultations often include discussions about:

• Smoking history and risk reduction  
• Support for smoking cessation 
• Lifestyle factors that influence lung health

Quitting smoking remains the most effective way to reduce lung cancer risk, even for individuals undergoing screening.

When Lung Cancer Screening May Not Be Suitable

Lung cancer screening is/may not appropriate for individuals who:

• Are pregnant 
• Have serious medical conditions that limit life expectancy 
• Are unable to undergo further investigations or treatment if abnormalities are found 
• Prefer not to pursue screening after understanding its benefits and limitations

Decisions about screening are individualised.

Commonly Asked Questions

Does lung cancer screening prevent cancer?

No. Screening does not prevent cancer, but it may help detect lung cancer at an earlier stage.

Is LDCT safe?

LDCT uses a lower radiation dose than standard CT scans and is considered appropriate for screening in high-risk individuals.

How often should lung cancer screening be done?

Screening intervals depend on individual risk factors, baseline and/or prior screening results and medical advice.

Can non-smokers undergo lung cancer screening?

The current local guidelines recommend annual low-dose CT scans for heavy smokers aged 50-80 years. While a family history of lung cancer has been associated with higher risk of developing the disease, the role of LDCT screening in non-smokers with positive family history is an area of ongoing research with no formal recommendations available.