About the disease itself but more tellingly about its treatments:
CNN.com: Survey: Many believe cancer myths
WASHINGTON (Reuters)—More than 40 percent of Americans surveyed in a study falsely believed surgery can allow cancer cells to spread through the body, researchers said Monday. And up to a quarter believed there is a drug industry plot to cover up a cure for cancer.
The survey, published in the journal Cancer, may mean patients with cancer may fail to get treatment or may fail to stick with it, the researchers said.
The telephone survey of 957 adults was designed to represent the general U.S. population, said the researchers, led by Dr. Ted Gansler of the American Cancer Society.
"The most prevalent misconception, 'Treating cancer with surgery can cause it to spread throughout the body,' was endorsed as true by 41 percent of the respondents," the researchers wrote in their report.
"The second most prevalent misconception, 'The medical industry is withholding a cure for cancer from the public in order to increase profits,' was identified as true by 27 percent."
I imagine the "surgery makes cancer spread" myth probably started with people who assumed (or were improperly assured by their doctors) that surgery would cure their disease, and the cancer had already metastasized to other parts of the body or something similar.
It's too bad most people have such blind faith in doctors. When I worked in a pharmacy for a time in 1994 and 1995, I was always just stunned when patients would ask us what a drug was for when they were picking up the prescription.
Why weren't they asking the doc what the drug's purpose was?