CT Screening in Lung Cancer Reduces Mortality, Study Finds

Early detection and treatment of lung cancer through screening with low-dose computed tomography (LDCT) has been investigated as a potential tool for reducing lung cancer deaths, the leading cause of cancer death worldwide, for more than 2 decades. Published this week was an extended follow up study to the 2011 randomized National Lung Screening Trial (NLST) that found a similar number of patients must be screened to prevent cancer deaths as determined in the original analysis.

In 2011, researchers published results from the NLST that found a significant 20% reduction in lung cancer mortality in high-risk current and former smokers who were screened annually for 3 years with LDCT as compared with chest x-rays. The study enrolled 26,722 patients in the LDCT arm and 26,730 in the x-ray arm across 33 medical institutions.

“Lung cancer is the leading cause of cancer death worldwide and early detection and treatment through screening with low-dose computed tomography has been investigated as a potential means of reducing lung cancer deaths for more than two decades. This study adds further weight to the notion that CT screening is effective,” Paul Pinsky, PhD, of the National Cancer Institute, said in a statement.

In the latest published report, the follow-up time was extended to 11.3 years for incidence and 12.3 years for mortality. The authors wrote that with an additional 6 years of mortality follow up, researchers could better understand if LDCT prevented deaths from lung cancer, or simply delayed them. The results determined that LDCT did, in fact, prevent lung cancer deaths in addition to delaying them for more than 10 years.

In the original report, authors noted that 320 patients would need to be screened in order to prevent 1 lung cancer death; however, in the follow up findings, the authors reported that only 303 patients would have to be screened to prevent 1 lung cancer death.

“With further follow up of NLST subjects, the originally reported reduction in lung cancer deaths in the LDCT versus [x-ray] arm was sustained; in contrast, the originally reported increase in lung cancer incidence was no longer observed,” wrote the authors.

Reference

Black W, Chiles C, Church T, et al. Lung cancer incidence and mortality with extended follow up in the national lung screening trial [published online June 28, 2019]. J Thorac Oncol. doi: 10.1016/j.jtho.2019.05.044.