What is a lung cancer screening?

A lung cancer screening is a test that uses a low-dose CT scan to catch signs of lung cancer before you have symptoms. It only takes a few minutes and is recommended yearly for certain adults who have a high risk of lung cancer due to their smoking history.

Lung cancer is one of the most common types of cancer. Many people don't know they have it until its later stages. Lung cancer screening is used for people who don't have symptoms to detect the disease at a very early stage when it's more likely to be cured. According to the National Cancer Institute, it's estimated that early detection and treatment of lung cancer could save more than 70,000 lives a year.

If you have a high risk of lung cancer, you'll need a referral from your primary care provider or pulmonologist to schedule a low-dose lung CT scan. Talk to your doctor to create a plan that's right for you.

Lung cancer screening guidelines

If you meet the guidelines, lung cancer screening is a quick, noninvasive way to gain peace of mind about your lung cancer risk, year after year.

The most recent lung cancer screening guidelines from the U.S. Preventive Services Task Force recommend screening if you:

  • Are 50 to 80 years old
  • Have a smoking history of 20 pack years or more (one pack year is defined as smoking one pack of cigarettes a day for a year or an equivalent amount)
  • Currently smoke or have quit smoking within the past 15 years
  • Have no symptoms

Talk to your provider if you think you meet the low-dose lung CT screening guidelines. If you currently smoke, you can qualify for annual screening, but your provider may also give you resources to help you quit for good.

How to calculate smoking pack years

A pack year equals smoking one pack of cigarettes a day for a year. A two-pack year is smoking two packs a day for a year. To calculate your total pack years, take the average number of packs you smoked per day and multiply it by the number of years.

For example:

  • Half a pack of cigarettes per day for 40 years equals 20 pack years.
  • Smoking one pack of cigarettes per day for 20 years equals 20 pack years.
  • Smoking two packs per day for ten years equals 20 pack years.

Using pack years helps provide a baseline to compare your smoking history. If you have a history of smoking that equals 20 pack years or more, you may qualify for screening under the guidelines.

About low-dose CT lung cancer screening

A low-dose CT scan for screening uses the same process as a regular CT scan but with a lower radiation dose. During the scan, the CT scanner takes multiple X-ray images to create a view of your lungs and look for lung nodules or signs of cancer.

Low-dose CT scans are recommended for those at high risk for lung cancer, as research shows that screening can save lives. In one study, known as the NELSON trial, screening led to a 33% drop in lung cancer deaths in women and a 24% drop in men.

Risks of low-dose CT lung cancer screening

While low-dose CT lung cancer screening has many benefits for those who qualify, it’s important to discuss the benefits and the risks with your provider.

Some risks of screening include:

  • Radiation exposure: The radiation used in lung cancer screening is less than that used in a regular CT scan, but it amounts to about the same radiation you would be exposed to in the natural environment over six months.
  • Added stress and anxiety: You may experience increased stress due to the screening or feel anxious about the results.
  • Follow-up tests: If the scan shows an area of concern, you may need other tests, some of which are more invasive.
  • False positives: Rarely, your provider may find an area on the scan that looks like cancer, but it’s harmless.
  • Incidental findings: CT scans of the chest sometimes show other health issues in your lungs or heart, leading to tests or care you might not have otherwise had. This, in turn, may also be informative in finding other unaddressed health issues you may have.

How to prepare for a lung cancer screening

Lung cancer screening is a quick, routine imaging test. You don’t need to do much to prepare for your CT scan, but you can do a few things to feel more prepared.

On the day of your screening:

  • Wear comfortable, loose-fitting clothes. Sometimes, you may change into a gown to have your scan.
  • Continue your normal diet and medications before and after the screening. Fasting is not necessary for this screening.

What to expect

Unlike an MRI scan, a CT scan is performed using an open piece of equipment—like a donut shape—and your whole body is never inside the machine all at once. The scan only takes a few minutes, but you’ll want to include extra time in your schedule for check-in, setup and checkout.

  • During lung cancer screening

    You will lie on a table during your lung cancer screening CT scan. To help you be more comfortable, your technologist may give you a pillow and help you get in the correct position. Lung cancer screenings don’t require any injections of medications or dye during the scan.

    Once you’re on the table, it will move through the CT machine while it takes multiple pictures of your chest using X-rays. You may be asked to lie with your hands raised above your head and hold your breath for 5-10 seconds as images are taken.

  • After lung cancer screening

    You don’t need to follow any special precautions after your scan. The images will be reviewed by a provider who specializes in diagnosing lung cancer through imaging tests. Then, your provider who referred you to get lung cancer screening will receive your results and answer any questions you have about your next steps.

Understanding the results

A few different results are provided to you and your provider after a radiologist reviews your scan. These include:


A positive result isn’t a diagnosis of lung cancer. It means that something in your scan needs additional follow-up. These abnormalities could include lung nodules that could be early lung cancer, scars from old lung infections or other non-cancerous growths.


You may need additional imaging tests to understand your lung health better.


Nothing abnormal was discovered. In this case, talk with your provider about another screening CT scan in a year.

If you have a lung nodule discovered on the screening CT, many of our locations provide coordinated teams that offer crucial follow-up care and treatment guidance. Your team will comprehensively assess your condition, discuss your concerns and questions and develop a care plan.

Most small nodules don’t need immediate attention and can be followed up by a CT scan in six or 12 months, depending on size. Larger or suspicious nodules might require additional testing, such as a three-month follow-up CT, PET scan or biopsy.

Patient story: A simple lung cancer screening saved my life

When Barney got a postcard about lung cancer screening for former smokers, he decided he should get checked. It’s a good thing he did. His CT scan revealed cancer. Days later, he had surgery to remove part of his lung. But because he caught his cancer early, he didn’t need chemotherapy.

Frequently asked questions

  • Is lung cancer screening covered by insurance?

    Yes. Most insurance providers, including Medicare, cover the cost of a lung cancer screening if you meet the guidelines and have a physician referral. But you should check with your insurance to understand what’s covered. Your standard copays and deductibles will apply if you need additional tests after your screening.

  • Who should be screened for lung cancer?

    You should be screened for lung cancer if you are 50-80 years old, have a smoking history of 20+ pack years (smoking one pack a day for 20 years or an equal amount) and currently smoke or have quit in the past 15 years.

    These screening guidelines are based on the recommendation of the U.S. Preventive Services Task Force. If you have questions about your risk of lung cancer, talk with your provider to see if you qualify for screening.

  • How often should lung cancer screening be done?

    For high-risk individuals, lung cancer screening is performed annually, even if your initial scan is clear. The U.S. Preventive Services Task Force recommends screening every year starting at age 50 until age 80, or when it’s been more than 15 years since you last smoked.

  • How long does a lung cancer screening take?

    The actual CT scan for lung cancer screening only takes a minute or two. However, I plan to be at the imaging center for about 30 minutes to allow time for check-in, setup, and checkout.

Contact us

If you are interested in self-referring for a lung cancer screening test (low-dose CT scan), please fill out the form below, and someone from our team will contact you soon.