Individuals who are 1ATD carriers should have lung function checked on a routine basis and should avoid potential lung carcinogens. "We found people who carry these genes are more vulnerable to carcinogen-containing tobacco smoke, even secondhand smoke, than noncarriers," says Dr. Yang.
In this study, a team of 12 researchers looked at three different groups: 1,443 patients with lung cancer treated at Mayo Clinic from 1997 to 2003; a control group of 797 residents in the community; and a second control group of 902 siblings of the lung cancer patients. They found that:
The 1ATD carrier rate among 1,443 genotyped patients with lung cancer was 13.4 percent, compared to 7.8 percent among unrelated control participants.
All 1ATD gene carriers were at a similarly greater risk of developing lung cancer, regardless of smoking status. Those who had never smoked were at a 2.2-fold higher risk; light smokers had a twofold greater risk; and moderate to heavy smokers had a 2.3-fold increased risk. Although there's no absolute definition, less than 20 pack-years of smoking cigarettes is defined as light; more than 40 pack-years as heavy. A pack-year is the number of packs of cigarettes smoked per day multiplied by the number of years the person has smoked.
A history of COPD increased lung cancer risk significantly for light, moderate and heavy smokers, but affected those who had never smoked the most X an almost sixfold increased risk.
Increased lung cancer risk among 1ATD carriers is independent of a family history of lung or other cancers.
The estimated attributable risk for 1ATD carriers in this study among those who never smoked and among heavy smokers was 11 percent to 12 percent, suggesting that the genetic disorder might explain a significant proportion
|Contact: Traci Klein|