Probability of Cancer in Pulmonary Nodules Detected on First Screening CT

Using data from two large data sets of lung-cancer screening by CT, the authors identified factors that increased the likelihood that a nodule was malignant, including older age, female sex, nodule location in the upper lobe, lower nodule count, and certain nodule features. The U.S. National Lung Screening Trial showed that screening with the use of low-dose thoracic computed tomography (CT) reduces mortality from lung cancer by 20%. 1 Major clinical issues in the implementation of low-dose CT screening at the population level include the definition of a positive screening result and the appropriate management of lung nodules detected on a scan. More than 20% of participants in low-dose CT screening programs were found on their first scan to have one or more lung nodules that required further investigation. 1 – 4 The proportion of invasive diagnostic procedures ranged from 1 to 4%. 1 , 3 The risk . . .