Lung Cancer Screening

Lung cancer screening is a test to detect lung cancer early, before symptoms develop. People between the ages of 50 and 80 with a 20 pack-year smoking history should consider screening every year. The screening uses a low-dose CT scan. It’s quick, painless and could save your life.


What is lung cancer screening?

Lung cancer screening is a test for lung cancer when symptoms aren’t present. Lung cancer screening detects 80% of lung cancer at an early stage, when treatment may work better.

An imaging exam called low-dose computed tomography, or low-dose CT, is the only recommended test for lung cancer screening. It’s a type of X-ray that creates very detailed pictures of your lungs.


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Who should have lung cancer screening?

Guidelines recommend that anyone who meets all of the following criteria receive a screening for lung cancer every year:

  • Between the ages of 50 and 80.
  • Currently smoke or quit within the last 15 years.
  • Have a 20-pack year smoking history.

A 20-pack year smoking history means you’ve smoked a pack (20 cigarettes) a day for 20 years. You calculate your “pack-years” by multiplying the number of years you’ve smoked by the number of packs you smoke each day. People who have smoked two packs per day for 15 years would have a 30 pack-year smoking history.

If you meet all of these lung cancer screening criteria, talk to your healthcare provider. They can refer you to the lung cancer screening program at your institution or write you an order for a low-dose CT and tell you where to get the screening. You should also call your health insurance company to confirm they will cover the cost of the scan. If you don’t have insurance, ask your healthcare provider about free or low-cost screenings.

When should someone stop lung cancer screening?

You can stop lung cancer screenings if you:

  • Develop a health condition that would prevent you from having treatments if the screening detects lung cancer.
  • Haven’t smoked for more than 15 years.
  • Turn 81.

Test Details

How do I prepare for lung cancer screening?

Most people don’t need to do anything to prepare for a lung cancer screening test. The imaging center where you receive your test will tell you if you need to do anything special to get ready.

If you’re sick or have any type of lung infection, tell your healthcare provider or the staff at the imaging center. You may need to reschedule your scan to ensure the results are as accurate as possible.

Right before your scan, your healthcare provider will ask you to:

  • Change into a gown, but sometimes you can keep your clothes on.
  • Remove jewelry, watches or anything metal you may be wearing.
  • Lie on a table outside of the CT scanner.

What happens during a lung cancer screening?

The table you’re lying on will slowly move inside the CT scanner. The machine is large, shaped like a donut. It goes all the way around your body so it can take multiple pictures of your lungs from every angle.

An imaging technician will talk to you during the entire scan. It’s important to lay very still.

The scan only takes a few minutes. It’s completely painless and doesn’t require any type of injection or sedative (medication to relax you). You can go home or back to work after the scan and perform all your normal activities.


Does lung cancer screening have any risks?

There is some radiation exposure during lung cancer screening. But it’s a small amount, smaller than a normal CT scan. That’s why they call this test a “low-dose” CT. If you’re at a risk for lung cancer, it’s safe for you to get the scan every year.

Other risks may include:

  • False positives: The scan may detect something in your lungs that looks like cancer, but isn’t. For example, most pulmonary nodules (small masses of lung tissue) are harmless. But you might have to get more tests and treatments before your healthcare provider confirms the growths aren’t cancer.
  • Incidental findings: The scan takes pictures of other parts of your body, not just your lungs. So, the pictures might detect other health problems. Sometimes this is helpful if the problem needs attention. But incidental findings can also be stressful since they lead to more tests.

Results and Follow-Up

When will I know the results of my lung cancer screening?

The length of time it takes to receive lung cancer screening results can vary. A radiologist reviews your scan and discusses it with your healthcare provider. Ask your healthcare provider when you can expect the results.

What if I have a positive lung scan?

If your healthcare provider finds anything abnormal on your scan, you may need more imaging tests. You may also need a biopsy. A biopsy uses a sample of tissue from your lungs to find out if you have cancer. If you do have lung cancer, your healthcare provider will discuss the next steps with you.

A note from Cleveland Clinic

Lung cancer screening is a safe and effective way to detect lung cancer in its early stages, when treatment may work better. The screening uses an imaging scan called a low-dose CT to take detailed pictures of your lungs. Screening is only for people who are at high risk for lung cancer due to their age and smoking history. Your healthcare provider can help you decide if lung cancer screening is right for you.

Medically Reviewed

Last reviewed by a Cleveland Clinic medical professional on 09/13/2021.

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