January 2, 2014
News Review From Harvard Medical School -- Group Recommends Lung-Cancer Screening
An influential expert panel has published its final report that recommends annual tests for people at high risk of developing lung cancer. In the past, screening of people without symptoms was thought to be useless for lung cancer. The tests either found too many harmless spots on lungs, or they did not find cancers early enough to save lives. The new advice comes from the U.S. Preventive Services Task Force. The U.S. government, doctors and insurance companies often follow its advice. The report recommends low-dose CT scans once a year for high-risk adults ages 55 to 79. A high-risk person is defined as someone who has smoked for at least 30 "pack-years." This could be 30 years of smoking a pack a day, 15 years at 2 packs a day or other combinations. Screening will be offered to anyone in this group who is a current smoker or has quit in the last 15 years. The task force based its advice on recent research. One study showed that a similar screening program could prevent about 1 in 5 lung cancer deaths. The journal Annals of Internal Medicine published the study December 31. HealthDay News wrote about it.
By Robert H. Shmerling, M.D.
Harvard Medical School
What Is the Doctor's Reaction?
If you are a heavy smoker -- or if you used to be -- the new lung-cancer screening guidelines are worth your attention.
Not long ago, experts thought early screening didn't work for lung cancer. Studies of yearly chest X-rays among smokers provided disappointing results. Some tumors could be detected, but they were often too advanced to cure.
But research in the last decade or so has confirmed that screening some high-risk people with CT scans is an effective way to detect lung cancer early. And this early detection can be enough to prolong -- or even save -- lives.
Here's what you need to know about the newly released, final report from the U.S. Preventive Services Task Force:
- High-risk adults between the ages of 55 and 79 should have a yearly CT scan of the lungs.
- A "high-risk" person is defined as anyone who:
- Currently smokes or quit within the last 15 years AND
- Has a 30 pack-year history of smoking. (This can mean smoking a pack a day for 30 years, 2 packs a day for 15 years and so on.)
- The CT scans used for screening should use "low-dose" radiation to minimize radiation exposure of people having yearly screening.
- Screening can be stopped when the person:
- Reaches age 80
- Develops a condition that greatly limits life expectancy
- Is unable or unwilling to have surgery if a tumor is found
Long-term heavy smokers have the highest risk of developing lung cancer. By limiting screening to this group, these guidelines should maximize the benefits. Using low-radiation scanning and excluding non-smokers also should minimize the "downsides" of screening, such as false alarms and expense.
These new guidelines are particularly important because the advice of the U.S. Preventive Services Task Force tends to be rapidly adopted by doctors.
What Changes Can I Make Now?
When it comes to lung cancer, prevention is even more important than early detection. And the biggest change you can make to prevent lung cancer -- by far -- is to not smoke. So, if you don't smoke, don't start. If you smoke now, commit to quit.
Quitting strategies include:
- Behavior programs, such as one-on-one counseling and support groups.
- Nicotine replacement in the form of skin patches, chewing gum, lozenges, nasal spray or inhalers. Electronic nicotine delivery systems (such as e-cigarettes) are the newest addition to this list, but we still don't know if they are safe and effective.
- Medicines, such as varenicline tartrate (Chantix) and buproprion (Zyban).
- Hypnosis, acupuncture and other alternative treatments. However, we don't have convincing evidence that they are effective.
If you are a former smoker, congratulations on quitting! But many former smokers find that it's a continual struggle to remain a non-smoker. Know that you aren't alone in your struggle and that help is available.
Although 85% of lung cancers are linked to cigarette smoking, the other 15% develop in non-smokers. It's not clear how well lung cancers in non-smokers can be prevented. These changes may help:
- Avoid secondhand smoke.
- Avoid exposure to asbestos. This is particularly a concern for people living in older homes with deteriorating insulation and for those with certain jobs (such as plumbers or shipyard workers).
- Avoid exposure to radon. Kits are available to have your home checked for radon gas. Well water should also be tested.
Talk to your doctor about getting screened for lung cancer if you are a current or former heavy smoker. If you are a good candidate for screening, the sooner you begin to have tests, the earlier a tumor might be detected.
What Can I Expect Looking to the Future?
We're used to thinking about early detection and early treatment as vital steps in improving the outlook for people with cancer. That's why mammograms are done to detect early breast cancers and colonoscopies are done to detect early colon cancer or polyps that can turn into cancer. These new guidelines for lung cancer screening extend the notions of early detection and early treatment to lung cancer. Because lung cancer is the leading cause of cancer death in the United States, the impact of these new guidelines could be big.
It will probably take years for these new guidelines to become a routine part of medical practice. One barrier is that health insurers may not cover CT scans. Given this new advice and the evidence on which it is based, I believe that coverage will become commonplace.
Once screening CT scans for lung cancer become widespread, you can expect researchers to study the impact. We may find that lung-cancer deaths begin to fall.