Doctors recommend lung CT scans to look for signs of lung cancer in current and former heavy smokers. Find out what to expect during lung cancer screening.
Lung cancer screening is a process that's used to detect the presence of lung cancer in otherwise healthy people with a high risk of lung cancer. Lung cancer screening is recommended for older adults who are longtime smokers and who don't have any signs or symptoms of lung cancer.
Doctors use a low-dose computerized tomography (LDCT) scan of the lungs to look for lung cancer. If lung cancer is detected at an early stage, it's more likely to be cured with treatment.
Discuss the benefits and risks of lung cancer screening using LDCT with your doctor. Working together will help you decide whether screening is right for you.
CT scans allow doctors to see cross-sectional images (slices) of your body. This slice shows heart and lung tissue.
The goal of lung cancer screening is to detect lung cancer at a very early stage — when it's more likely to be cured. By the time lung cancer signs and symptoms develop, the cancer is usually too advanced for curative treatment. Studies show lung cancer screening reduces the risk of dying of lung cancer.
Lung cancer screening is usually reserved for people with the greatest risk of lung cancer, including:
People who have smoked heavily for many years. You may consider lung cancer screening if you have a history of smoking for 20 pack years or longer. Pack years are calculated by multiplying the number of packs of cigarettes smoked a day and the number of years that you smoked.
For example, a person with 20 pack years of smoking history may have smoked a pack a day for 20 years, two packs a day for 10 years or half of a pack a day for 40 years. Even if your smoking habits changed over the years, your recollection about your smoking history can be used to determine whether lung cancer screening may be beneficial for you.
People in generally good health. If you have serious health problems, you may be less likely to benefit from lung cancer screening and more likely to experience complications from follow-up tests. For this reason, lung cancer screening is offered to people who are in generally good health.
Screening is generally not recommended for those who have poor lung function or other serious conditions that would make surgery difficult. This might include people who need continuous supplemental oxygen, have experienced unexplained weight loss in the past year, have coughed up blood recently or have had a chest CT scan in the last year.
Not all medical groups agree on the age at which you may consider stopping lung cancer screening. In general, continue annual lung cancer screening until you reach a point at which you're unlikely to benefit from screening, such as when you develop other serious health conditions that may make you too frail to undergo lung cancer treatment.
Lung cancer screening carries several risks, such as:
To prepare for an LDCT scan, you may need to:
Remove any metal you're wearing. Metals can interfere with the imaging, so you may be asked to remove any metal that you might be wearing, such as jewelry, glasses, hearing aids and dentures.
Wear clothes that don't have metal buttons or snaps. Don't wear an underwire bra. If your clothing has too much metal, you may be asked to change into a gown.
During an LDCT scan of the lungs, you lie on your back on a long table. You may be given a pillow to make you more comfortable.
The technologist who runs your scan will move to a separate room where he or she can still see you and talk with you.
You'll be asked to lie very still as the table slides through the center of a large machine that creates the images of your lungs. The table passes through the machine initially to determine the starting point for the scan.
When the machine is ready to start the scan, you may be asked to hold your breath briefly to create a clear picture of your lungs. The table will move quickly through the machine as the images are created. The machine may make knocking or clicking noises.
Expect your appointment to last about a half-hour, though the actual scan takes less than a minute.
When your LDCT scan is complete, you can go about your day normally.
The images created during the scan are compiled by a computer and reviewed by a doctor who specializes in diagnosing lung cancer with imaging tests (chest radiologist).
Examples of lung cancer screening results include:
Lung nodules. Lung cancer may appear as a small spot in the lungs. Unfortunately, many other lung conditions look the same, including scars from lung infections and noncancerous (benign) growths. In studies, as many as half the people undergoing lung cancer screening have one or more nodules detected on an LDCT.
Most small nodules don't require immediate action and will be monitored at your next annual lung cancer screening. In some situations, the results may suggest the need for another lung CT scan in a few months to see if the lung nodule grows. Growing nodules are more likely to be cancerous.
A large nodule is more likely to be cancerous. For that reason, you might be referred to a lung specialist (pulmonologist) for additional tests, such as a procedure (biopsy) to remove a piece of a large nodule for laboratory testing, or for additional imaging tests, such as a positron emission tomography (PET) scan.