CHICAGO, (Reuters Health) -- Computed tomography (CT) can detect
very early stages of lung cancer in older smokers at high risk for the disease,
according to a study presented this week at the 85th Scientific Assembly and
Annual Meeting of the Radiological Society of North America.
In addition, evidence of lung damage found on CT scans encouraged a
quarter of smokers screened for lung cancer to quit smoking even though they
were not found to have cancer.
Dr. Claudia I. Henschke, of Cornell University in New York, and colleagues
studied lung CT scans of 1,000 smokers and former smokers enrolled in the Early
Lung Cancer Action Program over 2 years. The study population consisted of
individuals age 60 years or older who smoked the equivalent of one pack of
cigarettes per day for 10 years. The people enrolled in the study had no prior
history of cancer and were medically fit to undergo chest surgery if necessary.
On repeat annual CT screening, 78 people were found to have lung nodules,
which can be caused by infection, inflammation, or benign or malignant tumors.
"Nine of these nodules were malignancies that would not have been found on
chest x-rays," Henschke told Reuters Health. These consisted of 1 small-cell and
8 non-small-cell lung cancers. She added that "88% of the non-small-cell lung
cancers were stage 1A," very early lung cancers. All the patients have undergone
treatment, Henschke said.
"Before we can recommend this as a national screening program, we must
follow the subjects with lung cancer to determine the cure rate to prove that
lives would be saved by using CT to annually screen smokers and former smokers
for lung cancer," she said in a statement.
"By screening with CT, cancers can be found when they're smaller than the
size of a grain of rice," Henschke said. "In cancers caught at the later stage,
there's a 10% to 14% five-year survival rate, whereas for those caught early,
survival moves up to 80%."
Henschke also reported on follow-up telephone interviews with 300 patients
who had completed the program's baseline CT screening and physician/patient
consultation. Twenty-three percent of these patients said the information they
received through the program convinced them to quit smoking.
The researcher told Reuters Health that viewing the CT scan of their
damaged lungs and reviewing the scans with their physicians seemed to be an
important motivating factor for the patients to quit smoking.
Statistics from the American Lung Association show that more than 160,000
Americans die of lung cancer each year, making it the leading cause of cancer
mortality in both men and women.
