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Word of the Day

Annual screening chest x-ray does not reduce lung cancer mortality

Clinical Question:
Can annual screening for lung cancer with chest radiography reduce mortality?

Bottom Line:
Compared with usual care, annual screening for lung cancer with chest radiography over a 4-year period does not reduce lung cancer mortality in never smokers, former smokers, or current smokers. (LOE = 1b-)

Oken MM, Hocking WG, Kvale PA, et al, for the PLCO Project Team. Screening by chest radiograph and lung cancer mortality. The Prostate, Lung, Colorectal, and Ovarian (PLCO) randomized trial. JAMA 2011;306(17):1865-1873.  [PMID:22031728]

Study Design:
Randomized controlled trial (nonblinded)




Previous studies have found no benefit from screening chest radiography for reducing lung cancer mortality. As part of a large study evaluating screening for multiple cancers, these investigators identified 154,901 men and women, aged 55 years to 74 years, who were randomly assigned (concealed allocation) to receive annual screening with a posterior-anterior chest radiograph for 4 years or usual care. Patients with a chest radiograph suspicious for malignancy underwent a standard diagnostic evaluation in consultation with their primary physicians. Diagnosed cancers and all deaths were ascertained by mailed annual study questionnaires, repeat mailings, telephone contact, and linkage to the National Death Index. Adherence to screening was 79% by year 3 and follow-up continued for 13 years. Screening chest radiographs were obtained by 11% of participants in the usual care group. Approximately 45% of participants were never smokers, 42% were former smokers, and 10% were current smokers. Using intention-to-treat analysis, there were no significant differences between the 2 groups in lung cancer incidence, lung cancer mortality, and cumulative mortality from other causes. Within the groups there was also no benefit to screening for any of the subgroups, including never smokers, former smokers, or current smokers. The study was 77% powered to detect a 20% mortality reduction.


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