William Pao, M.D., Ph.D., in the lab. (photo by Susan Urmy)
Lung cancer trial goes online for ‘never smokers’
One of the enduring mysteries of lung cancer is why so many people who never smoked develop the disease.
More than 219,000 people are diagnosed with lung cancer in the United States every year, according to the National Cancer Institute. About 20,000 — one in 10 — never smoked, and most are women.
Since tobacco exposure is the strongest known risk factor for lung cancer, researchers believe genetic differences may make some of these “never smokers” more likely to develop the disease.
William Pao, M.D., Ph.D., assistant director of Personalized Cancer Medicine at Vanderbilt-Ingram Cancer Center, is inviting those who have never smoked to join a Web-based clinical trial to search for those genetic differences.
“Our goal is to look at the DNA in blood or saliva samples as part of a future genome-wide association study,” said Pao, Ingram Associate Professor of Cancer Research. “You can look at more than half a million areas in the DNA where people may differ. When we start to see patterns in the DNA of patients like never smokers, we can try to identify genetic mutations that may be important in the lung cancer disease process.”
Pao and his colleagues hope to collect 2,000 DNA specimens from never smokers, who are defined as having smoked fewer than 100 cigarettes in their lifetime. Since a single cancer center doesn't see enough of these types of patients in a year to collect a large number of specimens, Pao turned to the Web to recruit patients.
“We believe this is the first study in a solid-tumor cancer to try to collect blood specimens through an online process,” said Pao. “Patients can go to our Web site, fill out a questionnaire, and if they qualify we will ship them two empty blood vials. The next time they visit their doctor, they can get those vials filled and ship them to us via UPS and we will pay the shipping. For those who can't get blood drawn, there is also an option of using saliva samples.”
To protect patient privacy, the DNA samples are de-identified when they are entered into the DNA databank, a secured databank designed to prevent tracing samples back to a specific donor.
“It is possible that there is some genetic susceptibility among never smokers that makes them more likely to develop the disease,” explained Pao.
Pao and other lung cancer investigators feel a sense of urgency because they still don't know enough about the genetic pathways that are important in the development and spread of the disease. According to the American Cancer Society, fewer than 20 percent of lung cancer patients are still alive five years after diagnosis.
“More than half of all lung cancer patients are diagnosed in the incurable stage, so we're already on the losing side of the battle with too many patients by the time we detect the cancer,” explained Pao.
“Eventually, this kind of study may help us identify genetic targets that allow us to develop simple blood tests to detect cancer early. Those same targets could be used to develop drugs that block or interfere with the disease process.”
For more information, visit http://www.vicc.org/neversmokers.