Summary

USPSTF 2021 Grade B recommendation for annual lung cancer screening with low-dose CT (LDCT) in high-risk adults defined by age and smoking history. Compared to the 2013 statement, the age range was expanded (was 55–80, now 50–80 years) and the pack-year threshold was lowered (was 30, now 20 pack-years), nearly doubling the eligible population and partially addressing racial/sex disparities in eligibility. Screening continues annually until 15 years of abstinence, limiting life expectancy, or inability/unwillingness to undergo curative lung surgery.

Key Recommendations

Screen adults aged 50–80 years with ≥20 pack-year smoking history who currently smoke or quit within the past 15 years using annual low-dose CT (Grade B).
Discontinue screening once the patient has not smoked for 15 years, develops a health problem that substantially limits life expectancy, or cannot/will not undergo curative lung surgery.
Use age and smoking history (not complex risk prediction models) to determine eligibility in primary care.
Engage in shared decision-making before screening, discussing benefits, false-positives, overdiagnosis, radiation, and incidental findings.
Provide concurrent smoking cessation interventions to all eligible patients who currently smoke.
Refer to a screening center with experience and expertise in LDCT lung cancer screening, ideally one using the Lung-RADS classification system for nodule reporting.
Do not use sputum cytology, chest radiography, or biomarker measurement for lung cancer screening — not beneficial.
Screen annually rather than biennially, based on CISNET modeling showing greater mortality benefit and life-years gained.

Thresholds & Doses

Age range for screening: 50 to 80 years (changed from 55–80 in 2013).
Smoking history threshold: ≥20 pack-years (changed from ≥30 in 2013).
Quit interval cutoff: currently smoking or quit within the past 15 years.
Stop screening: after 15 years of smoking abstinence, or when life expectancy/surgical candidacy is limited.
Screening interval: every 1 year.
Pack-year definition: 1 pack (20 cigarettes)/day for 1 year = 1 pack-year.
LDCT radiation dose: ~0.65–2.36 mSv per scan (background ~2.4 mSv/year).
NLST mortality benefit: ~20% relative reduction in lung cancer mortality (16% with extended follow-up); NELSON IRR 0.75 at 10 years.
Modeled benefit of A-50-80-20-15 vs A-55-80-30-15: 13.0% vs 9.8% lung cancer mortality reduction; 503 vs 381 deaths averted and 6918 vs 4882 life-years gained per 100,000.

Citations

Recommendation Summary table — eligibility criteria, age/pack-year thresholds, and Grade B assignment.
Clinician Summary ‘What’s new?’ — change from 55–80/30 pack-years to 50–80/20 pack-years.
Practice Considerations: Screening Tests — LDCT recommended; sputum cytology, chest x-ray, biomarkers not recommended.
Practice Considerations: Screening Intervals — annual LDCT preferred over biennial per CISNET modeling.
Practice Considerations: Smoking Cessation Counseling — concurrent cessation interventions required.
Practice Considerations: Standardization — Lung-RADS endorsed to reduce false-positives.
Update of Previous USPSTF Recommendation (Box) — A-55-80-30-15 (2013) replaced by A-50-80-20-15 (2021).
Supporting Evidence: Benefits — NLST (20% RR reduction) and NELSON (IRR 0.75) mortality data.