A large-scale, lung cancer screening trial has shown that heavy smokers who got spiral CT scans reduced their risk of dying by 20 percent compared to smokers who had standard chest X-rays.
"This difference is statistically significant, meaning that it's unlikely that it's just random variation between the two groups," said Dr. Tim Church from the University of Minnesota.
Spiral CT scans produce more detailed images of the lung.
More than 53,000 smokers participated in the study. The University of Minnesota recruited 6,600 smokers.
Church is not advising smokers to get a CT scan just yet.
"We have to make sure that we're not doing more harm than we should in getting that benefit," Church said. "And then once that analysis is done, recommendations can be formulated about who to screen, how often to screen, at what ages to screen and how long to screen them."
More sensitive CT scans can reveal lung masses that do not end up being cancerous. Church said investigating those false readings can be expensive and lead to needless surgeries and tests. In addition, all X-ray scans transmit radiation which can cause cancer.