Pop quiz: Treating cancer with surgery can cause the disease to spread to other parts of the body. True or false?

If you think the statement is true, you’re wrong, but you’re not alone.

More than half of the people questioned in a recent American Cancer Society survey mistakenly believed that surgery can or might spread cancer. And a significant percentage also believed other common cancer myths.

ACS researchers say the findings point to a need for greater public information efforts that target the poor and undereducated populations who tend to have the most misinformation about cancer.

“Our findings confirm that many people have misconceptions about cancer that may lead them to make choices which are not in the best interests of their health,” researcher Ted Gansler, MD, tells WebMD.

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Hiding a Cure

The ACS telephone survey included 957 randomly selected adults from across the nation who reported that they had no history of cancer. Among the most common misconceptions identified in the survey:

--41 percent said they believed surgery could spread cancer, and 13 percent said they didn’t know if this was true.

--27 percent agreed with the statement: “There is currently a cure for cancer but the medical industry won’t tell the public about it because they make too much money treating cancer patients.” Fourteen percent believed the statement might be true.

People who had not graduated from high school were three times as likely as college graduates to believe that a cure for cancer exists but is being withheld. In general, people who were older than 65, nonwhite, and living in the South had the most misconceptions about cancer, as did people who identified themselves as not knowing very much about the disease.

The survey results are published in the Aug. 1, 2005, issue of the ACS publication Cancer.

In a more encouraging finding, nine out of 10 people surveyed correctly disagreed with the statement, “All you need to beat cancer is a positive attitude, not treatment.”

An equal number did not agree with the statement, “Cancer is something that cannot be effectively treated.”

Also encouraging was that 68 percent of those surveyed rejected the statement, "Pain medications are ineffective against cancer pain."

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Myths Influence Treatment

Gansler says the widespread notion that surgery causes cancer to spread may stem from the once common practice of operating on patients to diagnose the disease. Patients whose cancers were too advanced to be treated often declined rapidly after diagnostic surgery.

“Because [nonsurgical] imaging is so advanced these days, it is not nearly as common for people to have surgical procedures that they are not likely to benefit from,” he says.

The idea that a cure for cancer is being withheld may stem from another misperception, Gansler says -- the mistaken belief that little progress has been made in treating the disease.

“Many people think in terms of a single cure for all cancers, which is highly unlikely,” he says. “What they don’t realize is that there are many people out there today who have been cured. A lot of progress has been made in many areas.”

He points out that just a few decades ago only about 10 percent of children with leukemia survived the disease. Today, 80 percent survive.

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Decisions Often Made on Bad Information

Cancer specialist Timothy Moynihan, MD, of the Mayo Clinic in Rochester, Minn., says patient misperceptions often influence their decisions about cancer treatment.

“Some people are reluctant to accept one type of therapy or another because of what they have heard,” he says. “That is especially true with regard to chemotherapy and its side effects. They often don’t understand that we have come a long way in making chemotherapy a whole lot easier on the patient than it used to be.”

Myths about pain management are also common, he says.

“A lot of people are concerned that if they take a pain medicine now it won’t work later,” he says. And they worry about becoming addicted. These are both common myths.”

People who harbor these cancer misconceptions may increase their risk for cancer death and disability because they may make inappropriate health care decisions or may have poor adherence to treatments, they write.

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By Salynn Boyles, reviewed by Brunilda Nazario, MD

SOURCES: Gansler, T., Cancer, Aug. 1, 2005, online edition. Ted Gansler, MD, MBA, director of medical content, American Cancer Society, Atlanta. Timothy Moynihan, MD, cancer specialist, Mayo Clinic, Rochester, Minn.