Low-Dose CT Screening
A low-dose CT scan can find lung cancer before symptoms appear in people who may benefit from screening.
Understanding Low-Dose CT
Low-dose computed tomography (LDCT) is a specialized type of CT scan that uses less radiation than a standard chest CT. It creates detailed cross-sectional images of the lungs, allowing doctors to detect small nodules or abnormalities that may indicate early-stage lung cancer.
LDCT is the screening test recommended by the United States Preventive Services Task Force (USPSTF) for people who meet its eligibility criteria. Screening can find lung cancer before symptoms appear, when treatment may be more effective. It also has potential harms, including false-positive results, additional testing, overdiagnosis, and radiation exposure.
Less radiation.
Detailed lung images.
Typical adult doses; the actual dose varies by patient and imaging protocol. ACR / RSNA dose reference.
What to Expect During Your Scan
An LDCT scan is fast, painless, and non-invasive. Here is the experience from start to finish.
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01
Schedule
Talk with your healthcare provider about eligibility and an order for screening. Call 1-844-YES-LUNG for help finding resources.
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02
Arrive
Check in at the imaging center and follow its preparation instructions. You may be asked to change into a gown and remove metal objects.
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03
Scan
Lie on the table as it moves through the CT scanner. The scan usually takes only a few minutes, with a brief breath hold.
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04
Results
A radiologist reviews the images. Your healthcare provider explains the results and any follow-up needed; timing varies by center.
Sources: ACR / RSNA lung screening information.
Relative reduction in lung cancer mortality
The National Lung Screening Trial compared LDCT with chest X-ray in people at high risk. This is a relative reduction in lung cancer mortality, not a reduction in everyone’s overall chance of dying.
What the result means
NCI describes about 3 fewer lung cancer deaths per 1,000 people screened with CT over approximately 7 years of observation.
These cumulative figures and the trial’s relative mortality estimate use different statistical measures. Individual benefit depends on risk and health.
Sources: National Cancer Institute: NLST.
2021 USPSTF Screening Guidelines
Under the USPSTF recommendation, adults meet the screening criteria when all three details apply. The American Cancer Society’s guideline does not use years since quitting as a cutoff.
Age 50–80
You are between 50 and 80 years old.
≥20 Pack-Years
You have a smoking history of 20 pack-years or more (e.g., 1 pack/day for 20 years).
Smoking History
You currently smoke or have quit within the past 15 years.
Screening is intended for people without signs or symptoms of lung cancer. Discuss symptoms with a clinician instead of waiting for a screening appointment. USPSTF recommends stopping when someone has not smoked for 15 years or cannot or does not wish to undergo curative lung surgery. The ACS guideline differs on years since quitting.
Sources: USPSTF · ACS 2023 guideline.
Understand your coverage
Many people who meet screening criteria can receive LDCT without a screening copay. Check the requirements of your own plan before scheduling.
Medicare
Medicare Part B covers annual LDCT for eligible people aged 50–77 who meet its smoking-history and other requirements. You pay nothing for the covered screening if the provider accepts assignment. A shared decision-making visit is required before the first screening.
Other insurance
Most private plans cover recommended preventive lung cancer screening for eligible people when plan requirements are met. Medicaid coverage and network rules can vary. Follow-up scans or procedures may have different costs.
Sources: Medicare screening coverage · HealthCare.gov preventive services.