What are the guidelines for lung cancer screening?

Lung Cancer Screening Guidelines

Annual screening for lung cancer with low-dose computed tomography (LDCT) is recommended for adults aged 50-80 years who have a 20 pack-year or greater smoking history and currently smoke or have quit within the past 15 years. 1, 2

Eligibility Criteria for Lung Cancer Screening

High-Risk Population Recommended for Screening

• Adults aged 50-80 years 2
• Minimum smoking history of 20 pack-years (number of packs per day × years smoked) 2
• Current smokers or former smokers who have quit within the past 15 years 2
• Asymptomatic individuals who are disease-free at the time of screening 3

When to Discontinue Screening

• Once a person has not smoked for 15 years 2
• When an individual develops health problems that substantially limit life expectancy 2
• When there are comorbidities that limit the ability or willingness to undergo curative lung surgery 2

Screening Protocol and Technical Specifications

Screening Modality

• Screening should be performed using LDCT multidetector scanner 3
• Technical parameters: 120-140 kVp, 20-60 mAs, with average effective dose of 1.5 mSv or less 3
• Collimation should be 2.5 mm or less 3
• Chest X-ray is NOT recommended for lung cancer screening 3

Screening Frequency

• Annual screening is recommended for eligible individuals 2, 3
• Screening should continue annually until the person no longer meets eligibility criteria 3

Management of Screening Findings

Definition of Positive Results

• Nodule size of 5 mm or more warrants a 3-month follow-up CT 3
• Nodules of 15 mm or more require immediate further diagnostic procedures 3

Follow-up Protocol for Positive Findings

• For nodules 6-7 mm: LDCT in 6-12 months 3
• For nodules 8-14 mm: LDCT in 3-6 months 3
• For nodules ≥15 mm: Chest CT with contrast and consideration of biopsy or surgical excision 3
• Follow-up CT should be done as a limited LDCT scan covering only the nodule area 3

Implementation Considerations

Program Requirements

• Screening should be performed in organized screening programs with expertise in lung cancer screening 3
• Programs should have access to a multidisciplinary team with expertise in evaluation, diagnosis, and treatment of abnormal lung findings 3
• Shared decision-making discussion with qualified health professionals should occur before initiating screening 1, 4
• Current smokers should receive smoking cessation counseling and be connected to cessation resources 1

Quality Assurance

• Individuals who are screened should be enrolled in a registry to capture data on follow-up testing, radiation exposure, patient experience, and smoking behavior 3
• Quality metrics should be developed to enhance benefits and minimize harms 3

Benefits and Harms of Screening

Benefits

• Reduction in lung cancer mortality through early detection 2, 5
• Expanded eligibility criteria (age 50-80,20+ pack-years) compared to previous guidelines increases potential lives saved 5
• Early-stage lung cancer has better prognosis and is more amenable to treatment 2

Potential Harms

• False-positive results (approximately 1.9-2.5 per person screened) 5
• Overdiagnosed lung cancer cases (83-94 per 100,000 screened individuals) 5
• Radiation-related lung cancer deaths (29-42.5 per 100,000) 5
• Unnecessary invasive diagnostic procedures 4

Special Considerations

Risk-Based Screening Approaches

• Risk prediction models incorporating additional factors beyond age and smoking history may improve screening efficiency 6
• Additional risk factors that may be considered include sex, race/ethnicity, family history of cancer, history of COPD or emphysema 6
• Risk model-based strategies may provide more benefits with fewer radiation-related deaths compared to risk factor-based strategies 5

Common Pitfalls to Avoid

• Screening individuals outside the recommended age and smoking history parameters 3
• Using chest X-ray instead of LDCT for screening 3
• Failing to engage in shared decision-making before initiating screening 1
• Not providing smoking cessation counseling to current smokers 1
• Screening individuals with limited life expectancy who would not benefit 2