For patients at the highest risk for lung tumors, screening with low-dose CT prevented the greatest number of deaths, according to research results in the New England Journal of Medicine. Using imaging was not as successful among those at lowest risk, and prevented very few deaths, the authors found.
Researchers used data from the National Lung Screening Trial (NLST) and assessed the variation in efficacy, the number of false positive results, and the number of lung-cancer deaths prevented among 26,604 participants who underwent low-dose CT screening, as compared with the 26,554 participants who underwent chest radiography, according to the quintile of 5-year risk of lung-cancer death.
In their analysis of data from more than 53,000 volunteers, investigators found that among those with the lowest risk, CT screening prevented only one additional lung cancer death per 50,000 people each year, compared to screening with conventional X-rays. In the highest risk group, CT screening saved about one additional life per 800 people.
Researchers believe that the results of the study, which was funded by the National Cancer Institute, provide empirical support for risk-based targeting of smokers for such screening.