A U.S. study of current and former smokers shows that early screening with CT scans cuts the death rate for lung cancer by 20 percent. The findings are significant because lung cancer is an aggressive disease that often is undetected, and once diagnosed, the mortality rate is very high.
Angela Tauro underwent a CT scan at Yale University Hospital and a cancerous tumor was removed from one of her lungs. "I am alive today because I had a CT [CAT] scan rather than an X-ray," she said.
From 2002 to 2004, more than 53,000 middle-aged smokers who had a pack a day habit for 30 years or more participated in the National Lung Screening Trial. Former smokers also qualified, if they had quit within a 15 year period.
One group underwent three yearly screenings with the CT scan. Another group was given chest X-rays.
Researchers found that an X-ray could not see early signs of cancer in the lungs. But computerized axial tomography, better known as a helical CT scan, provided doctors with far greater detail.
Dr. Christine Berg of the National Cancer Institute was a director of the screening trial. "You can hold your breath during that time and get very thin pictures through the entire lung and see very small abnormalities," she said.
The survival rate for lung cancer is low. Fewer than 15 percent of those diagnosed with the disease live more than five years. But Dr. Berg says early screening with low dose CT scans can dramatically improve the odds. "If you're diagnosed with Stage 1 disease, which we can now do with the low dose helical CT, your survival may be 60 percent at five years. That's still not 100 percent, but we are making progress," she said.
Results of the study showed a 20 percent reduction in lung cancer deaths among those who had CT scans, compared to those who had undergone chest X-rays.
There are drawbacks associated with the use of helical CT scans. More than one fifth of the scans resulted in false positive readings.
In the United States, the cost of a CT screening is not always covered by health insurance. But some hospitals have begun to reduce the price of a CT scan to encourage smokers like Leslie Greissing to come in. She says she is glad she did. "It would reveal anything that might be brewing that would otherwise be undetectable," she said.
Because helical CT scans are not widely available in many parts of the world, Dr. Berg says the best way to prevent lung cancer is simple. Don't take up smoking. And if you're already a smoker, quit.
An earlier version of this story contained factual errors. VOA regrets the error.