Among subjects at high risk for lung cancer who were screened in three rounds of CT scanning and in whom noncalcified pulmonary nodules were evaluated according to volume and volume-doubling time, the chances of finding lung cancer 1 and 2 years after a negative first-round test were 1 in 1000 and 3 in 1000, respectively. (Current Controlled Trials number, ISRCTN63545820.)

Several medical associations recommended lung cancer screening by low-dose computed tomography scanning for high-risk groups. Counselling of the candidates on the potential harms and benefits and their lung cancer risk is a prerequisite for screening.In the NELSON trial, screenings are considered positive for (part) solid lung nodules with a volume .500 mm 3 and for (part) solid or nonsolid nodules with a volume-doubling time ,400 days. For this study, the performance of the NELSON strategy in three screening rounds was evaluated and risk calculations were made for a follow-up period of 5.5 years.458 (6%) of the 7582 participants screened had a positive screen result and 200 (2.6%) were diagnosed with lung cancer. The positive screenings had a predictive value of 40.6% and only 1.2% of all scan results were falsepositive. In a period of 5.5 years, the risk of screen-detected lung cancer strongly depends on the result of the first scan: 1.0% after a negative baseline result, 5.7% after an indeterminate baseline and 48.3% after a positive baseline.The screening strategy yielded few positive and false-positive scans with a reasonable positive predictive value. The 5.5-year lung cancer risk calculations aid clinicians in counselling candidates for lung cancer screening with low-dose computed tomography. @ERSpublications 5.5-year lung cancer risk calculations aid clinicians in counselling for lung cancer screening with low-dose CT

Compared with electrocardiography-triggered CT, nontriggered CT is extensively used. In 2007, 13.6 million nontriggered thoracic CT examinations were performed in the United States, in contrast to 0.7 million electrocardiography-triggered CT examinations for calcium scoring. 7 Recent trial results have increased the interest in lung cancer screening by thoracic CT.8 Thus, the number of nontriggered examinations will likely further increase. Age and smoking, the current selection criteria for lung cancer screening, are also correlated with coronary calcification and coronary heart disease.9 In lung cancer screening, coronary calcification is a frequent finding.10 If nontriggered CT can be used for calcium scoring, to stratify individuals in categories of cardiovascular risk and to identify Background-Coronary calcium score (CS), traditionally based on electrocardiography-triggered computed tomography (CT), predicts cardiovascular risk. Currently, nontriggered thoracic CT is extensively used, such as in lung cancer screening. The purpose of the study was to determine the correlation in CS between nontriggered and electrocardiographytriggered CT, and to evaluate the prognostic performance of the CS derived from nontriggered CT.