USPSTF recommends annual CT for patients at high risk of lung cancer

Patients at high risk for lung cancer should be screened annually with low-dose computed tomography (CT), the U.S. Preventive Services Task Force (USPSTF) recently recommended.

Specifically, the guideline recommended annual CT screening for adults age 55 to 80 years who have a 30 pack-year smoking history and currently smoke or have quit within the past 15 years. Screening should be discontinued once a person has not smoked for 15 years or develops a health problem that substantially limits life expectancy or willingness to have curative lung surgery, the USPSTF advised.

The recommendation, which was published online Dec. 31 by Annals of Internal Medicine, was based on adequate evidence of moderate certainty (primarily the National Lung Screening Trial), the statement said. It updated the Task Force's 2004 recommendation, which found insufficient evidence to recommend for or against screening.

The new recommendation noted that harms of screening include false negatives and false positives, incidental findings, overdiagnosis and radiation exposure. Patients in the screened population should also receive smoking cessation treatment, and the decision to screen should be shared between clinician and patient after a “thorough discussion of the possible benefits, limitations, and known and uncertain harms.” Screening should be done in accordance with quality standards and protocols for follow-up, the recommendation said.

The recommendation was based on a comparative modeling study, also published by Annals on Dec. 31, which found that the screening strategy chosen by the USPSTF would lead to 50% of lung cancers being detected at stage I or II, 575 screens per lung cancer death averted, and a 14% (range, 8.2% to 23.5%) reduction in lung cancer mortality and 5,250 life-years gained per 100,000 people born in 1950 (the cohort used in the model). As for screening harms, the strategy would cause 67,550 false positives, 910 unnecessary biopsies or surgeries and 190 overdiagnosed cases of cancer, the model showed.

Two editorials were also published with the recommendation. One raised questions about the implementation of the recommendation, including the challenge of getting high-risk patients to submit to screening and refraining from screening patients who request scans but don't meet the criteria. The editorialist also asked how much of the responsibility for screening will fall on primary care physicians versus other clinicians. A second editorial expressed concern about the Task Force's reliance on modeling and the wide variation in harms and benefits of screening within the population recommended for screening.