#LUNG CANCER XRAY TRIAL#

Among people who had multiple annual screens (up to three screens) 39.1 percent had at least one positive screen in the CT arm and 16.0 percent had at least one positive screen in the chest X-ray arm. On average, over all three screening rounds, 24.2 percent of the low-dose helical CTs were positive and 6.9 percent of the chest X-rays were positive and led to a diagnostic evaluation. What did the study find about false-positive results?Ī positive screening result was defined as one in which a nodule or other finding was observed that was potentially related to lung cancer. If lung cancer deaths were excluded, the differences in all causes of mortality between low-dose helical CT and chest X-ray were not statistically significant. This difference was largely due to the decrease in lung cancer mortality.

Were there any other important findings from this study?Īn additional finding, which was not the main endpoint of the trial's design, showed that all-cause mortality (deaths due to any factor, including lung cancer) was 6.7 percent lower in those screened with low-dose helical CT relative to those screened with chest X-ray.

#LUNG CANCER XRAY TRIAL#

The 15 percent to 20 percent lower lung cancer death rate is equivalent to approximately three fewer deaths per 1,000 people screened in the CT group compared to the chest X-ray group over an average of 6.5 years of follow-up in the trial (17.6 per 1,000 versus 20.7 per 1,000). This finding was highly significant from a statistical viewpoint, meaning it was due not to chance but rather to screening with helical CT. The NLST researchers found approximately 15 percent to 20 percent fewer lung cancer deaths among trial participants screened with low-dose helical CT relative to chest X-ray. Over a 21 month period, 53,454 current or former heavy smokers ages 55 to 74 joined the NLST at study centers across the United States.

Both chest X-rays and helical CT scans have been used as a means to find lung cancer early, but the effects of these screening techniques on lung cancer mortality rates had not been determined definitively. Launched in 2002, NLST compared two ways of detecting lung cancer: low-dose helical (spiral) computed tomography (CT) and standard chest X-ray, for their effects on lung cancer death rates in a high-risk population. The National Lung Screening Trial (NLST) is a lung cancer screening trial sponsored by the National Cancer Institute (NCI) and conducted by the American College of Radiology Imaging Network (ACRIN) and the Lung Screening Study group.

Lung cancer xray