A new urine test that tests the levels of the chemical NNAL may be able to tell which smokers are more likely to contract lung cancer.
The chemical NNAL has been linked to lung cancer. Those who have high levels of the chemical in their urine have a 8.5 increased risk of developing cancer.
The test has been studied in about 500 men and women in Shanghai and Singapore. Results from the study were presented at the annual meeting of the American Association for Cancer Research.
“A history of smoking has always been thought of as a predictor of lung cancer, but it is actually not very accurate,” said Dr. Jian-Min Yuan, associate professor of public health at the University of Minnesota. “Smoking absolutely increases your risk, but why it does so in some people but not others is a big question.”
The chemical NNAL is created as the body metabolizes tobacco. It has been shown to induce lung cancer in lab animals but the effect is just now starting to be studied in humans.
Researchers say that the test is not a means to give smokers a license to smoke. There are many other health risks associated with tobacco uses. The U.S. Centers for Disease Control and Prevention estimates that about 23 percent of adult Americans are smokers, and smokers account for about 87 per cent of cases of lung cancer, the number one cancer killer.
The study showed that those with a medium-level NNAL test had a 43 percent higher risk of cancer and those with the highest levels had a twofold higher risk.
This evidence held true regardless of how many cigarettes a person smoked per day, the number of years of smoking, and urinary levels of another chemical, cotinine, on lung cancer risk.
Science Daily reports:
“Smoking leads to lung cancer, but there are about 60 possible carcinogens in tobacco smoke, and the more accurately we can identify the culprit, the better we will become at predicting risk,” said Yuan.
The researchers collected data from 18,244 men in the Shanghai Cohort Study and 63,257 men and women in the Singapore Chinese Health Study. They then looked at 246 current smokers who later developed lung cancer and 245 smokers who did not. The study participants were followed for 10 years.
Scientists could perfect the current test within a few years according to Yuan. The current test costs about $100 to $120. There is a catch, other than quitting smoking there is no intervention known if the risk factor is there.