CT screening for lung cancer finds more cancers, after more investigationsBMJ 2013; 346 doi: https://doi.org/10.1136/bmj.f3401 (Published 28 May 2013) Cite this as: BMJ 2013;346:f3401
We know that screening for lung cancer with computed tomography (CT) prevents more deaths from lung cancer than screening with a chest radiograph, but what happens to adults screened by one or other modality? A descriptive account of the first round from a landmark screening trial reports that a quarter of high risk adults screened with CT had some kind of abnormality (27.3% (7191/26 309)), compared with a 10th of controls screened with chest radiography (9.2% (2387/26 035)). More positive CT scans meant more follow-up imaging (5717 v 2010), biopsies (155 v 83), bronchoscopies (306 v 107), and surgery (297 v 121). Ultimately, more cancers were diagnosed in adults screened with CT (1.1% (292) v 0.7% (190)). The extra cancers were mainly stage 1A.
One round of CT screening was more sensitive than radiography (93.8% v 73.5%) but less specific (73.4% v 91.3%). The positive predictive value was low for both tests (3.8% v 5.7%). All participants were screened for the first time between 2002 and 2004, at age 55-74 years. About half were former smokers. The rest were still smoking when recruited. All had a history of at least 30 pack years, the equivalent of smoking 20 cigarettes a day for 30 years.
Cite this as: BMJ 2013;346:f3401