English
Annual CT Scans for Heavy Smokers Recommended
Posted on Aug 07, 2013 by Ailee Slater (G+)
Late last month, the U.S. Preventive Services Task Force released new recommendations regarding lung cancer screening. At the moment, most lung cancer detection programs rely on chest C-rays and mucus tests; however, according to the Task Force, a screening process known as low-dose computed tomography (or LDCT) is far more effective and should be used in annual lung cancer tests.
Like a normal CT scan, low-dose computed tomography processes X-rays through a computer in order to view three-dimensional, cross-sectional images of the body. CT scans can, therefore, give a doctor more information than an X-ray, which is only a two-dimensional picture. However, CT scans expose the body to far more radiation than a traditional X-ray; hence the Task Force's recommendation that rather than asking patients to undergo a yearly CT scan to check for lung cancer, they do a low-dose scan instead, which operates with less radiation.
Still, the Task Force is not suggesting that all smokers take a yearly low-dose CT scan: rather, these annual screenings should be reserved for patients aged 55 to 79 who are heavy smokers. In this case, a heavy smoker is defined as a person who has been smoking an average of one pack of cigarettes per day for at least 30 years. According to the Task Force, even former smokers should take an annual low-dose CT scan as well - the recent National Lung Screening Trial found that former heavy smokers who had quit for fewer than 15 years still had a greater-than-average risk of cancer, and could definitely benefit from annual low-dose CT scans once over the age of 55.
Michael LeFevre, co-vice chairman of the Task Force, has said that if their annual screening recommendations are followed, we could see the prevention of 20,000 deaths per year. Lung cancer is responsible for killing more than 150,000 people every year in the United States, making the fatality rate of lung cancer higher than that of breast, prostate and colon cancer together.
Especially frightening about lung cancer is the fact that 90 percent of patients with lung cancer will die as a result of the disease. Detecting lung cancer early, however, gives patients a much better chance at survival, which may be why the Task Force has decided to study and emphasize the importance of low-dose CT scans. With frequent, high quality screening, patients who do discover cancer can begin treatments much sooner. This early treatment may include removal of cancerous growth by surgery, or radiation therapy.
Interestingly, the Task Force has never before recommended annual lung cancer screening; at least, not screening that uses traditional X-rays - two-dimensional X-rays are simply not good enough at picking up lung cancer in its early stages. When cancerous cells are just beginning to form they will be too small to be visible by X-ray; with CT scans, however, even the very initial stages of lung cancer are normally detectable.
The Task Force is so convinced of this new lung cancer screening research that the group has issued a Grade B recommendation - meaning that current and former heavy smokers aged 55 to 79 will be able to receive insurance coverage when undergoing annual low-dose CT scans. The Affordable Care Act mandates that all insurers must cover any procedure receiving a Grade A or Grade B recommendation from the Task Force.
Of course, annual CT scans do carry some risks; even when the scans are conducted using low levels of radiation. Some doctors and patients already express concerns about the potent X-rays involved in a CT scan; these rays have been shown to produce enough energy to affect DNA, which could in turn lead to cancer. At the same time, the link between CT scans and cancer is heavily debated, and few doctors nowadays would recommend forgoing an important CT screening for fear of increasing a patient's cancer risk.
Indeed, radiologists in the United States have reacted quite positively to the Task Force's recommendations that heavy smokers receive an annual low-dose CT screening. As reported by USA Today, radiologist Reginald Munden of the University of Texas has said that the slight risk that comes with a CT scan is, for a heavy smoker, far outweighed by the health benefits of annual screenings. Munden has even pointed out that, in terms of radiation, a CT scan is no more dangerous that living for one year in a town situated at sea level.
Besides radiation, another possible problem with yearly CT scans is that these tests can often produce false positives - showing signs of lung cancer when in fact a patient has no cancerous growths. A false positive can lead a patient to further screenings and radiation exposure, as well as unnecessary surgery and anxiety. But, again, the Task Force concluded that yearly CT screening for heavy smokers can save a huge amount of lives, and the potential disadvantages from false positive tests will most likely be minimal.
With smoking posing such an enormous health risk, and costing health care systems around the world hundreds of thousands of dollars every year, it makes sense that the U.S. Preventive Services Task Force would be pleased to formally encourage lung cancer screening, with solid research to back up that recommendation. So although the exact risks and possibilities of low-dose CT scans are not yet completely understood, it's a good bet that we will see more examination of this medical service in the future.