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Harvard Reviews of Health News


Lung Cancer CT Scans Recommended for Heavy Smokers

Heavy current and past smokers ages 55 to 74 should get yearly lung CT scans, according to new guidelines from several major medical groups. A panel of cancer and chest experts reviewed the results of past studies. One study, the National Lung Screening Trial, found that yearly low-dose CT scans could reduce deaths from lung cancer by 20%. Heavy smokers are people who have smoked a pack of cigarettes a day or more for 30 years. About 160,000 people will die of lung cancer in 2012 in the United States. Testing comes with risks, said the experts. These include side effects from radiation and more tests. The Journal of the American Medical Association published the new guidelines online May 20. HealthDay News and the Associated Press wrote about them May 21.

What Is the Doctor's Reaction?

Lung cancer is usually discovered late. Either it involves too much of the lung or has spread beyond the lung. Until recently, no method of lung cancer screening appeared to improve overall survival.

A report published last year suggested that screening heavy smokers with yearly low-dose CT scans could reduce deaths from lung cancer by 20%. The results are from the National Lung Screening Trial. The study included more than 53,000 current and former heavy smokers between the ages of 55 and 74.

Based on these study results, three well-respected medical groups are recommending CT screening yearly for heavy smokers in this age group.

Lung cancer is responsible for about one-quarter of all cancer deaths. This far surpasses deaths from breast cancer in women and prostate cancer in men. A 20% reduction in lung cancer deaths would mean more than 30,000 lives saved a year. So, it sounds like the recommendations are a no-brainer.

But the physical, emotional, and monetary costs of saving these lives with yearly screening is enormous. About 24% of the CT scans showed areas of concern that required additional testing to determine if lung cancer was present. But only 5% of these worrisome looking spots turned out to be cancer. That means a lot of people are getting yearly radiation without it improving their health.

Radiation is not the only risk. More testing was always necessary. Sometimes this meant needing a lung biopsy or bronchoscopy to determine if the spot was a cancer. Bronchoscopy is a procedure in which a tube is threaded down into the airway. In addition to generating worry or even panic, these false positives sometimes led to injury and even death during the follow-up procedures.

To keep one person from dying of lung cancer, an estimated 320 heavy smokers need screening. Or put another way, 319 out of 320 people who get screened will not benefit from screening. And some will be harmed.

An estimated seven million American adults meet the "heavy smoking" standard for the National Lung Screening Trial. If low-dose lung CT scans cost $300, we could pay over 2 billion dollars a year just for scans. That does not include the billions more needed to do follow-up testing and procedures on worrisome spots.

What Changes Can I Make Now?

The new recommendations pose a problem. The groups suggest that people only get screened in places where there are specialists experienced in reading and following-up on the CT scans. This limits access to the majority of eligible "heavy smokers."

Right now, insurance is unlikely to cover your cost of a screening CT scan, even if you are between ages 55 and 74 and a prior or present heavy smoker. If you can afford the $300, the choice to get a scan is a personal one. Understand that a worrisome spot seen on a CT scan has a 95% chance of not harming you. You may need additional tests to be sure it isn't cancer. And these have real and potential risks of harm.

CT scans can't prevent lung cancer. At best, they can detect lung tumors early enough that they can be cured by surgery.

The best way to prevent lung cancer is to never smoke or to quit. One of the lessons we've learned is that it is never too late to quit. If you quit at age 60, you stand to tack on about three years to your life expectancy. Quit at 50, and you earn six extra years. Quit at 30, and a whole decade is deposited into your life expectancy account.

There's no better health deal around.

What Can I Expect Looking to the Future?

Many doctors, including myself, heavily rely on recommendations made by the U.S. Preventive Services Task Force. This government sponsored group assigns expert panels to create guidelines on medical issues like cancer screening. They last published guidelines on lung cancer screening eight years ago. At that time, they stated there was not enough evidence to recommend any type of lung cancer screening.

They are reviewing their prior guidelines. Their recommendations will influence insurance coverage and what doctors advise their patients.

Author: Howard LeWine, M.D.
Date Last Reviewed: 5/22/2012
Date Last Modified: 5/22/2012