Urine test may predict lung cancer risk

DENVER, April 20 (UPI) -- U.S. and Chinese researchers say levels of a metabolite in urine may help predict those at risk for lung cancer.

The study, presented at the annual meeting of the American Association for Cancer Research in Denver, found patients with mid-range level of the metabolite -- NNAL -- had a 43 percent increased risk of lung cancer over those with low levels.

After taking into account several factors such as years of smoking, those with highest levels of NNAL had a more than two-fold increased risk of lung cancer.

Also, those with the highest levels of nicotine and NNAL had an a more than eight-fold increase in the risk of lung cancer compared with smokers who had the lowest levels.

"Smoking leads to lung cancer, but there are about 60 possible carcinogens in tobacco smoke," study leader Dr. Jian-Min Yuan of the University of Minnesota said in a statement. "Smoking absolutely increases your risk, but why it does so in some people but not others is a big question."

The researchers interviewed and collected urine and blood from 50,000 patients taken from 18,244 men enrolled in the Shanghai Cohort Study and 63,257 men and women from the Singapore Chinese Health Study, and after 10 years evaluated the impact of NNAL in 246 smokers who developed lung cancer and 245 smokers who did not develop lung cancer.