In a new draft recommendation(www.uspreventiveservicestaskforce.org), the U.S. Preventive Services Task Force (USPSTF) has updated its 2004 position, proposing that physicians screen high-risk, 55- to 79-year-old adults for lung cancer on an annual basis using low-dose CT scans.
According to USPSTF Co-vice Chair Michael LeFevre, M.D., M.S.P.H., the task force is making the draft recommendation because screening the right people will save lives.
"Over 200,000 people are diagnosed with lung cancer each year, and about 160,000 will die," he said. "Smoking is the biggest risk factor therein, resulting in about 85 percent of U.S. lung cancers. Your risk goes up the more you smoke and the longer you smoke, and it also goes up with age."
LeFevre, a family physician from Columbia, Mo., said the task force drew the line at age 55 after reviewing the evidence. He said the data placed 55- to 79-year-old, one-pack-a-day smokers who smoked for 30 years squarely in the high-risk category. That math also includes two-pack-a-day smokers who've been lighting up for 15 years, and so on.
- The U.S. Preventive Services Task Force (USPSTF) has issued a draft recommendation proposing that physicians screen high-risk, 55- to 79-year-olds for lung cancer annually using low-dose CT scans.
- High-risk adults in this age group include those who have accumulated 30 cigarette pack-years and are still smoking or who quit within the past 15 years.
- Although the USPSTF still recommends complete tobacco cessation, "casual" smokers are not recommended for screening.
"Generally healthy people in that age range with at least a 30 pack-year history of smoking who are either still smoking or have quit within the last 15 years are all candidates to consider screening," he said. "When you're 15 years (or more) out from quitting, we would not recommend screening. So, if everybody in the United States quit smoking today, we wouldn't be screening anybody for lung cancer 15 years from now."
Before age 55, the balance of benefits and harms shifts, according to LeFevre. In younger patients, the high rate of false-positive results associated with lung cancer screening can lead to additional imaging, which, in turn, results in more radiation, anxiety and, in some cases, lung surgery to prove there is no cancer.
"There are risks of going down that cascade of testing and treatment, so we want to minimize that by focusing on the high-risk groups," he said.
LeFevre said that when making these screening decisions, family physicians certainly should consider a patient's overall health and not just his or her age and smoking history. But because the negative effects of smoking depend on the maximum amount of smoke inhaled, "casual" smokers do not fit into the high-risk screening category.
"Zero is better than a few cigarettes every six weeks, and passive smoke is also bad, but those people are also not accumulating a high pack-year ratio because it takes a lot of years to get to a pack-year at three cigarettes every six weeks," LeFevre explained. "Of course, our recommendation is still zero (cigarettes), as risks remain. But from a screening standpoint, we aren't talking about the casual smoker who lacks a significant smoking history. The balance of benefit and harm is better served by focusing screening on those high-risk groups."
The draft recommendations will be open for public comment(www.uspreventiveservicestaskforce.org) until Aug. 26 at 5 p.m. EDT.
The AAFP is reviewing the task force's draft recommendations and will update its own 2004 lung cancer screening recommendations after the USPSTF publishes its final recommendation statement in late 2013 or early 2014.