Lung Cancer: Still the Biggest Cancer Killer, by Far

"It looks like the effect of tobacco is the same for women as it is for men," said Dr. Tim Byers, deputy director of the University of Colorado Cancer Center and a professor with the university's department of preventive medicine and biometrics.

Other recent research has discovered a genetic variant tied to lung cancer risk. Doctors earlier this year found a 70 percent increased risk of the disease among carriers of a deficient gene called Alpha 1-antitrypsin.

But given that smoking is the cause of nearly all lung cancers, doctors aren't sure that knowledge of a genetic link will prove useful in the near term. "There's nothing that can be done about this genetic variant," Thun said.

The most promising area of new research involves early detection of lung cancer through the use of spiral CT scans.

Currently, when lung cancer is detected, the disease has already spread outside the lung in 15 percent to 30 percent of cases, according to the National Cancer Institute. That's because chest X-rays can only detect larger tumors of 1 centimeter or more.

But spiral CT, a technology introduced in the 1990s, can pick up tumors well under 1 centimeter.

About 50,000 current or former smokers are participating in the National Lung Screening Trial, a study that hopes to determine in the near future whether CT scans can allow early intervention that would save a person's life.

"We all have our fingers crossed that the trial will show there is a screening procedure that will make a difference," Byers said. "We're probably about two to three years away from knowing the results of that trial."

In the meantime, doctors say the best way to save lives from lung cancer is to throw more energy into measures that will prevent smoking.

Studies have shown that raising the price of cigarettes through taxation, clean air laws that prohibit smoking in public places, and counter-advertising have all helped reduce smoking rates in the United States, Thun said.

"We know those tactics work, but, for political reasons, they're not being fully applied," he said.

Quitting smoking also will allow people to avoid the host of other health problems that come with it, most notably cardiovascular disease.

"If you avoid smoking, you have avoided the Mount Everest of avoidable health hazards," Thun said.

More information

To learn more, visit the Lung Cancer Alliance.

SOURCES: James Mulshine, M.D., professor of internal medicine and associate provost for research, Rush University Medical Center, Chicago; Michael Thun, M.D., M.S., vice president of epidemiology and surveillance research, American Cancer Society, Atlanta; Tim Byers, M.D., M.P.H., deputy director of the University of Colorado Cancer Center, and professor, Department of Preventive Medicine and Biometrics; Lung Cancer Alliance; U.S. National Cancer Institute