Lung Cancer Screening


Lung Cancer Screening involves checking for a disease when it has no symptoms or history. Doctors prescribe a screening test when care can work best to detect a disease early on.


Low-dose computed tomography (also called a low-dose CT scan, or LDCT), is the only approved screening procedure for lung cancer. You lie on a table during an LDCT scan, and an X-ray machine uses a low dose (amount) of radiation to make accurate pictures of the lungs. The exam takes only a couple of minutes, and is not painful.


Who Should Be Screened?


The U.S. Preventive Services Task Force recommends yearly lung cancer screening with LDCT for people who:


  • Have a history of heavy smoking, and
  • Smoke now or have quit within the past 15 years, and
  • Are between 55 and 80 years old.


Heavy smoking means a smoking history of 30 pack years or more. A pack year is smoking an average of one pack of cigarettes per day for one year. For example, a person could have a 30 pack-year history by smoking one pack a day for 30 years or two packs a day for 15 years.


Risks of Lung Cancer Screening


Screening has at least three risks


  • A lung cancer-screening test can suggest that a person has lung cancer when no cancer is present. This is called a false-positive result. False-positive results can lead to follow-up tests and surgeries that are not needed and may have more risks.
  • A lung cancer-screening test can find cases of cancer that may never have caused a problem for the patient. This is called over diagnosis. Over diagnosis can lead to treatment that is not needed.
  • Radiation from repeated LDCT tests can cause cancer in otherwise healthy people.


That is why lung cancer screening is recommended only for adults who are at high risk for developing the disease because of their smoking history and age, and who do not have a health problem that substantially limits their life expectancy or their ability or willingness to have lung surgery, if needed.


If you are thinking about getting screened, talk to your doctor. If lung cancer screening is right for you, your doctor can refer you to a high-quality screening facility.


The best way to reduce your risk of lung cancer is to not smoke and to avoid second hand smoke. Lung cancer screening is not a substitute for quitting smoking.


When Should Screening Stop?


The Task Force recommends that yearly lung cancer screening stop when the person being screened:


  • Turns 81 years old, or
  • Has not smoked in 15 or more years, or
  • Develops a health problem that makes him or her unwilling or unable to have surgery if lung cancer is found.