Oct. 26, 2011 (Honolulu) -- Getting a routine chest X-ray is not likely to reduce your chance of dying from lung cancer.
That's the result of a study published in The Journal of the American Medical Association and presented at the annual meeting of the American College of Chest Physicians.
It came as a disappointment because more people die of lung cancer worldwide than any other cancer. Researchers are looking for ways to detect lung cancer before it grows too difficult to treat effectively.
"We were hopeful the chest X-rays we did would make a difference," study researcher Paul A. Kvale, MD, tells WebMD.
Still, another expert stresses that patients should not assume chest X-rays are useless. They are still helpful in cases where doctors already have some reason to believe the patient has cancer.
"We should not confuse the value of the chest X-ray in someone who has symptoms of lung cancer with the value of the chest X-ray in someone who does not have symptoms," says Frank C. Detterbeck, MD. Detterbeck is a Yale University lung cancer specialist. He was not involved in the new study.
Lung Cancer Chest X-Ray Study
About 154,900 people took part in the new study. Half got routine chest X-rays every 1.5 years. The other half did not get any routine chest X-rays.
Thirteen years later, both groups had about the same number of deaths. And the results were also similar when the researchers looked at people with risk factors for lung cancer, such as smoking.
Kvale, a pulmonologist at Detroit's Henry Ford Hospital, says he wasn't surprised by the results because previous studies had also found that chest X-rays were not effective enough in catching the lung cancer to save lives. "It's not something that is recommended by any professional association or lay group such as the American Cancer Society."
So why would researchers bother to study it again? The previous studies were smaller and some had flaws, so experts still hoped that the previous results might have been wrong. The new study pretty much lays that hope to rest, Kvale says, because "this was the biggest study of its kind ever done."
But the study wasn't a waste of time, Kvale says. Based on the results of this study and others, experts are likely to recommend screening people who have smoked a lot or have other risk factors -- but using a different test, a low-dose chest CT.
CT Scans Instead?
High-risk patients screened with low-dose chest CT scans were 20% less likely to die from lung cancer than patients screened with chest X-rays in a study published in the New England Journal of Medicine in August.
The American Cancer Society and at least three other groups are working on new guidelines for lung cancer screening. They're already considering this research, says Detterbeck, who is co-chair of the lung cancer guidelines coalition.
The details are complicated, Detterbeck tells WebMD. Low-dose CT scans often find things that look like cancer, but are not. That may lead doctors to do further tests, some of which come with a risk of harming the patient.
So Detterbeck's team is trying to figure out exactly what group has a high enough risk of lung cancer that the benefits of screening with low-dose CT outweigh the risks. "Selection of the appropriate patient population is something we have to pay careful attention to," he says.