The Scan’s The Plan!

Think the risks of cigarette smoking are exaggerated? Lung cancer tops the list of deaths from cancer in the United States. Smoking causes 85 percent of all lung cancers, and about one-third of all adults in the U.S. smoke. That’s a lot of people at risk, and lung cancer is deadly — about 90 percent of patients die of the disease.
The most common type is non-small cell lung cancer, or NSCLC. As with other cancers, the earlier it is found, the higher chance for a cure. Make no mistake though, lung cancer is very deadly. If it has already spread to distant parts of the body when discovered, the 5-year survival rate is only about 4 percent. Bleak. If the spread is more limited to only the area’s lymph nodes, the 5-year survival rate is still only 25 percent. If localized only to the lung and no spread to the lymph nodes, survival is 52 percent, still not very encouraging. However, if detected at the earliest stage, the 5-yr survival for NSCLC is 77 percent — way more encouraging than the 4 percent of late-detected cancer.
Unfortunately, only a small percentage of lung cancers are discovered at the earliest stages. Screening has been studied using regular chest x-rays; cell studies of sputum from the lungs; and computed tomography (CT or “CAT”) scans that give very detailed images. Of these, the low dose CT (LDCT) is the most sensitive for catching early lung cancers. Despite some excitement in this area, in 2004 the United States Preventive Services Task Force (USPSTF) determined that there was not enough evidence to recommend screening for lung cancer in people without symptoms. However, further studies led to a new recommendation last year that those at high risk of lung cancer be screened with LDCT annually, symptoms or not.
What’s high risk? You are at high risk for lung cancer if you are age 55-80, and have a history of heavy smoking, and currently smoke or have quit within the past 15 years. Smoking is measured by how many “pack years” a person has smoked. To figure your pack years, multiply the number of packs you smoke per day times the number of years you have smoked. Some examples: If you’ve smoked 1 pack per day (PPD) x 30 years = 30 pack years. If you’ve smoked 2 PPD x 15 years = 30 pack years. Or 3 PPD for only 10 years = 30 pack years. In all of these examples, you would be considered a heavy smoker and at high risk of lung cancer.
Are there any exceptions? Yes, but only a few. You can stop annual screening when you have stopped smoking for 15 years. The only other exception would be if you develop a condition that severely limits your life expectancy (you’re going to die of something else before the lung cancer) or your ability to undergo lung surgery if cancer is found in the screening.
Are there any risks? Of course there are a few to be considered with your primary care provider (PCP), but these are small. The main risk is that of a false-positive. This is when lung cancer is detected on the LDCT screening scan, but in fact, there is no cancer present. This could lead to unnecessary biopsies, surgeries, and anxiety, each with some associated morbidity and even mortality.
Even the LDCT involves a small amount of radiation. But one scan is less than the normal amount of background radiation we all receive during the year, a little more than a mammogram, and a little less than a head CT. Since the risk of radiation is cumulative, the larger number of years that you receive the annual screenings, the more increase in the small chance of a radiation-induced lung cancer.
The USPSTF has studied the risks and benefits of LDCT and concluded that the benefits significantly outweigh the risks of LDCT screening for lung cancer in those at high risk. Using evidence-based techniques, the USPSTF has assigned a high Level B grade to its recommendation for LDCT lung cancer screening. It can be a real life saver — please discuss your risks with your PCP soon and stay healthy.

Dr. Fleming is the Medical Director of The Jane Pauley Community Health Center (closely affiliated with Community Health Network). Ideas for this column can be e-mailed to Dr. Fleming at Or you can write your medical questions to Dr, Fleming at AskDrFleming, 8931 E. 30th Street, Indianapolis, IN 46218. On written correspondence, please include your name and city (names will not be published).