Concomitant screening of coronary artery disease and lung cancer with a new ultrafast-low-dose computed tomography protocol. a pilot randomised trial

We performed a pilot randomised study to assess the feasibility and radiation exposure of a new computed tomography (CT) protocol that allows screening of both coronary artery disease (CAD) and lung cancer. Current or former heavy smokers at high lung cancer risk with indication to cardiac CT for suspected or known CAD were randomised to undergo concomitant CT evaluation of either cardiac or thoracic area or cardiac CT only. Out of 129 subjects deemed eligible for the study, 110 agreed to participate and were randomised to simultaneous cardiac and lung CT (Gr. A; n = 55) or cardiac CT only (Gr. B; n = 55). The feasibility (i.e. adequate visualization of coronary artery segments) was noninferior with simultaneous cardiac and lung CT compared with the standard cardiac CT (870 of 889 segments [97%] in Gr. A vs 878/890 segments [99%] in Gr. B; mean difference 2.0% [90% confidence interval: -0.3% to 4.1%]). The safety (i.e. effective radiation dose) of the concomitant cardiac and lung CT protocol was noninferior to the standard cardiac CT (1.5 [95% confidence intervals: 1.2-1.7] vs. 1.4 [95% confidence intervals: 1.1-1.6] mSv; mean difference 0.1 mSv [90% confidence interval: -0.2 to 0.3 mSv]). In the two groups, a total of 25 significant (> 70%) coronary stenoses were found at cardiac CT (9/55 cases of Gr. A vs 11/55 cases of Gr. B). Pulmonary nodules > 2 mm were detected in 7 of the 55 Gr. A subjects. This pilot randomised study shows that concomitant CAD and lung cancer screening by means of a new CT protocol is both feasible and safe, thus allowing a comprehensive evaluation of both cardiac and thoracic regions during one CT scanning only.