Lung cancer takes the lives of more Amercians than any other form of the disease, but a screening test that could reduce the death rate is vastly underutilized, a top expert says.

That test is low-dose computed tomography (CT) screening, a noninvasive form of imaging that produces high quality images, enabling smaller lung cancer tumors to be detected, while a cure is still possible, Dr. David Tom Cooke tells Newsmax Health.

“An estimated 9 million people in the U.S. are at high risk for lung cancer. If just half of them were screened, an estimated 15,000 lives a year could be saved, but less than 5 percent undergo it,” says Cooke, head of general thoracic surgery at UC Davis Health in Sacramento, Calif.

About 222,500 new cases of lung cancer (116,990 in men and 105,510 in women) are diagnosed each year. The disease kills about 155,870 people (84,590 men and 71,280 women) annually, the American Cancer Society (ACS) says.

About one out of every four cancer deaths are from lung cancer, and each year, more people die from it than colon, breast, and prostate cancers combined.

Lung cancer generally does not have early symptoms, so, by the time it is detected, the disease has spread, vastly reducing the likelihood of a cure.

“Currently, the five-year survival rate is 15 percent, but low-dose CT scanning picks up the disease at an earlier stage, when the survival rate is 50-80 percent,” adds Cooke, a volunteer spokesman for the American Lung Association, which is promoting the test as part of November, which is lung cancer awareness month.

For the past 20 years, some experts had been promoting the use of low-dose CT scanning for lung cancer screening but research results were mixed, and there was a concern over the test’s high rate of “false positives,” which means it picks up abnormalities that lead to further testing but are later shown to be harmless.  

But the U.S. Preventative Services Task Force (USPSTF) shifted its stance in 2013, citing results of the National Lung Screening Trial, a major study which found that people at high-risk of lung cancer that underwent the test had a 20 percent lower risk of dying than those diagnosed with chest x-rays.

Annual screening with low-dose CT scanning is recommended for current smokers ages 55-80 who have at least a 30 pack-year smoking history and are either still smoking or have quit within the last 15 years.

A pack-year is the number of cigarette packs smoked each day multiplied by the number of years a person has smoked, so someone smoked a pack of cigarettes per day for 30 years has a 30 pack-year smoking history, as does someone who smoked 2 packs a day for 15 years, the recommendation says.

Screening is not indicated for people who have not smoked for 15 years, the guidelines say.

But the test is underutilized, says Cooke.

“When you look at public awareness among both patients and their primary care physicians, it’s just not there.”

He also cites the lung association’s annual survey, which queried 1,000 people, but found that 84 percent of those people queried who would qualify for screening didn’t know about the test.

“That survey showed that the top reason people had for not getting the test was that their doctor hadn’t recommended it,” Cooke says.

Also, only 15 percent were aware that Medicare and most major health insurers cover the test, he adds.

Another problem is that, even though lung cancer is No. 1 cancer killer of women, few recognize it.

“In the survey, only 28 percent of women knew their greatest cancer risk was lung cancer, because they tend to focus on breast cancer,” Cooke says.  

Breast cancer kills about 40,610 women annually, which is just over half the number of female deaths that lung cancer causes.

“The threat that lung cancer poses is underappreaciated but we have this tool that can save lives. But it’s not being used, and people need to talk to their doctors about it,” says Cooke.