CT Scans of Smokers Cut Lung Cancer Deaths by 20%
Trial Comparing CT With Standard X-ray Screening for Lung Cancer Halted Early
Lung Cancer Screening: Trial Results continued...
The 20% reduction with CT scans is termed “very important," by Gastonis.
''What we are showing is, heavy smokers can see a benefit here [with CT screening] in mortality," he says.
According to the NCI, for every 300 participants screened with low-dose helical CT, one life has been extended.
A surprise finding is that the CT screening group also had a 7% reduction in overall death rate from any cause compared to the chest X-ray group, he says.
The ''false-positive" rate -- those screenings that detected an abnormality that upon further evaluation was not lung cancer -- was about 25% in the trial, Gatsonis says. In other studies of lung cancer CT screenings, the rate of abnormalities shown in former and current smokers ranged from 20% to 60%, with most of the abnormalities not turning out to be lung cancer.
The false positives, experts say, can cause anxiety and tests such as biopsies that could turn out to be negative.
But finding the cancer early with screening can extend life.
Screening for Lung Cancer: Perspective
The reduction found with CT scans over standard X-rays is very good, says Regina Vidaver, PhD, executive director of the National Lung Cancer Partnership, a nonprofit organization devoted to research and education.
"Having a 20% decrease in mortality from screening is outstanding," she tells WebMD. She was not involved in the study but reviewed the findings for WebMD.
She points out, however, that the study included only heavy smokers and that one in four is ''a very high false-positive rate."
Screening for Lung Cancer: Practical Matters
Reimbursement for a lung low-dose helical CT scan, used as it was in the trial as a screening test before any symptoms or signs arise, is not provided by most insurance carriers, according to the NCI.
The estimated Medicare reimbursement for a diagnostic CT of the lung when lung cancer is suspected is about $300, the NCI says.
The study results are expected to provide valuable information to help experts make recommendations for screening, Gatsonis says.
The machines to perform low-dose helical CT scans are widely available at hospitals and free-standing radiology clinics in the U.S., according to the NCI. In the test, X-rays scan the entire chest in about 15 seconds, with the scanner rotating around the person as he lies still on a table. Images from the X-ray data are fed to a computer, and two-dimensional pictures of the lungs with great detail are produced.
Berg has this advice: “I would personally recommend that a heavy smoker with no signs or symptoms of lung cancer go talk to their physician and discuss the findings released today.” A decision about cancer screening should be based on medical history and other factors, she says.