What to Expect Before, During, and After Your Lung Cancer Screening

Lung cancer is the number one cause of cancer deaths in the United States for both men and women. Lung cancer doesn’t cause symptoms until it’s already at an advanced stage. Lung cancer screening aims to find the disease at an earlier stage before you have symptoms. This is when treatment is more effective.

The only proven test for this purpose is low-dose computed tomography (LDCT). In LDCT, a specific type of X-ray machine scans your body and uses a low dose of radiation to create high-quality images of your lungs. Research has shown that screening high-risk persons with LDCT can reduce the risk of dying from lung cancer.

Yet screening also has a downside: It may detect lung abnormalities that prompt additional testing or procedures but don’t turn out to be lung cancer. Those “false alarms” can cause worry and the additional procedures may have complications.

To help make sure the benefits outweigh the risks, yearly lung cancer screening is for people who meet all the following criteria:

• Ages 50 to 80    

• Have a 20 or more pack-year history of smoking cigarettes (this means smoking 1 pack a day for 20 years or 2 packs a day for 10 years)

• Currently smoke or have quit smoking within the past 15 years

• No serious illnesses that would stand in the way of treating lung cancer

Screenings should be stopped if you:

• Haven't smoked for 15 years

• Develop a serious, life-limiting condition

• Aren’t willing or able to get treatment for lung cancer

Make sure you discuss the pros and cons of lung cancer screening with your health care provider to see if it is right for you.

Here’s a quick look at what to expect.

Before the test

Metal can affect the image on LDCT scans. Before your scan, you’ll be asked to remove metal objects, such as jewelry, hairpins, eyeglasses, and removable dental work.

During the test

LDCT is a painless, noninvasive imaging test. In the test, an X-ray machine scans your body in a spiral path. At the same time, the exam table is moving through the scanner so that the X-ray beams follow the spiral path. This machine is linked to a computer, which processes the scanned information and creates a series of detailed images. During this test, you’re exposed to 90 percent less radiation than with a conventional CT scan of the chest. LDCT for lung cancer screening does not require a needle stick, IVs, or any medicines or blood draws. 

The machine used for LDCT typically looks like a large donut. You’ll lie on a table that slides in and out of this donut.

Once you’re in position, the table slides through the tunnel quickly to find a starting point for the scan. Then the table slides through a second time as the scan is performed. During this scanning process, any motion—even breathing—could blur the image. You’ll need to hold your breath for five to 10 seconds.

After the test

About one in four LDCT screenings find abnormal areas in or near the lungs. Most turn out to be something other than cancer, such as scarring from a past infection. To know for sure, however, you’ll likely need follow-up testing.

Often, you’ll be asked to come back for another LDCT scan in several months. By comparing the 2 scans, your health care provider can see whether the abnormal area is growing. If it is growing, your health care provider may recommend further evaluation. You might need to get another type of imaging study or a biopsy (removal of tissue for analysis in the lab).

At every step along the way, your health care provider should clearly explain the process. If you have any questions about getting screened or understanding the results, don’t hesitate to ask.

And remember, if you haven’t quit smoking cigarettes yet, LDCT is not a substitute for quitting.

For more information about lung cancer screening, take a look at the resources from VHA’s National Center for Health Promotion and Disease Prevention and the VA Lung Cancer Screening Decision Aid.