Due to the National Lung Screening Trial (NLST) findings, the American Lung Association (ALA) is recommending lung cancer screening with low-dose CT scans for people who meet certain criteria, which include the following: current or former smokers (aged 55 to 74 years), with a smoking history of at least 30 pack-years and with no history of lung cancer.
The purpose of a CT screening test is to identify the presence of cancer in an individual that does not demonstrate any symptoms, according to ALA. The association emphasized that only CT scans are recommended, and chest x-rays should not be used for lung cancer screening.
In August 2011, the National Cancer Institute released results from its NLST, a randomized trial that screened at-risk smokers with either low-dose CT or standard chest x-ray. The study found that screening individuals with low-dose CT scans could reduce lung cancer mortality by 20 percent compared with chest x-ray. These "exciting results" led the ALA to reexamine its organization’s policy on lung cancer screening. As such, the ALA convened a Lung Cancer Screening Committee, chaired by Jonathan M. Samet, MD, to review the current scientific evidence on cancer screening to assist the ALA in offering the best possible guidance to the public and those suffering from lung disease. This is the first report of the ALA's Lung Cancer Screening Committee.
The committee acknowledged that cancer screening is associated with both benefits and risks and "unfortunately, the NLST could not answer a number of questions on the advantages and safety of screening in the general population," the association added. In spite of this, the committee provided the following interim recommendations:
- The best way to prevent lung cancer caused by tobacco use is to never start or quit smoking.
- Low-dose CT screening should be recommended for those people who meet NLST criteria: current or former smokers, aged 55 to 74 years; a smoking history of at least 30 pack-years; and no history of lung cancer.
- Individuals should not receive a chest x-ray for lung cancer screening.
- Low-dose CT screening should not be recommended for everyone.