Top Five Cancer Misconceptions

It's hard to keep up with all the latest news on cancer, and a new survey from the American Cancer Society (ACS) shows that many Americans still harbor potentially dangerous misconceptions about the disease. Not being fully informed about the risks could promote cancer-causing behaviors, says lead survey author Kevin Stein of ACS.

To determine how cancer-savvy the U.S. public is, Stein and his team created 12 false or unsubstantiated statements about cancer risk and risk factors, then asked nearly 1,000 U.S. adults by phone whether they believed the statements to be true, false, or if they didn't know.

Below are the top five misconceptions from the survey, published in the Sept. 1 issue of Cancer.

1. The risk of dying from cancer in the United States is increasing.

About 68% of those surveyed believed this to be true, although the cancer mortality rate has actually been decreasing since the 1990s. Overall, thanks to more aggressive screening programs and better treatments, the five-year survival rate of all cancers taken together has been climbing for the past 30 years, from 51% between 1975 and 1977 to 67% in 2004.

2. Living in a polluted city is a greater risk for lung cancer than smoking a pack of cigarettes a day.

Almost 40% of adults who responded thought car and bus exhaust posed a greater hazard to their lungs than smoking. While some studies have begun to document an up to 12% greater risk of dying from lung cancer in urban residents, the strongest data consistently show that smoking is the leading cause of the disease. Anywhere from 80% to 90% of lung-cancer deaths can be attributed to lighting up.

3. Some injuries can cause cancer later in life.

Another 37% believed this to be true, despite the fact that most cancers can be traced to a progression of genetic changes that are independent of physical injuries.

4. Electronic devices, like cell phones can cause cancer in the people who use them.

Nearly 30% believed this, although there is no scientific evidence to prove or disprove the relationship between cell-phone use and brain cancer. The National Cancer Institute continues to study any possible links, but they note that the rapidly changing technology of cell phones (newer phones emit less potential cancer-causing radiation than older models) and the difficulty of documenting the duration of people's exposure could make a definitive answer difficult.

5. What someone does as a young adult has little effect on their chance of getting cancer later in life.

In spite of the fact that many of the more common cancers, including skin cancer and lung cancer, are associated with behaviors such as sunbathing and smoking early in life, 25% of respondents believed that such behaviors do not increase long-term cancer risk.