FRANCE – Conducted every 5 years since 2005, the Cancer Survey documents the knowledge, perceptions, and way of life of the French people in relation to cancer. The researchers analyzed responses to telephone interviews of a representative sample of almost 5,000 individuals aged 15-85 years.
This study shows how thinking has changed over time and how difficult it is to alter preconceived notions.
Is cancer hereditary?
The report shows that 67.7% of respondents believe that cancer is a hereditary disease. Respondents were asked to explain their answer. “Data show that medical practices for cancer treatment substantiate this belief [that cancer is hereditary],” wrote the authors of the report.
“Indeed, health care professionals almost systematically ask questions about family history of breast cancer and, when a family member has been diagnosed with cancer, medical monitoring of other family members is often sought out, thus reinforcing the belief that cancer is hereditary,” they said.
Furthermore, there seems to be confusion regarding the role of genes in the development of cancer. A person can inherit cancer-predisposing genes, not cancer itself. The authors highlighted their concern that this confusion may “lead people to think that prevention measures are unnecessary because cancer is inherited.”
Misconceptions about smoking
About 41% of smokers think that the length of time one has been smoking is the biggest determining factor for developing cancer; 58.1% think the number of cigarettes smoked per day has a bigger impact.
Experts at InCA and SPF put the debate to rest, stating that prolonged exposure to carcinogenic substances is far more toxic. As for the danger threshold concerning the number of cigarettes smoked per day, respondents believed this to be 9.2 cigarettes per day, on average. They believed that the danger threshold for the number of years as an active smoker is 13.4, on average.
“The [survey] respondents clearly understand that smoking carries a risk, but many smokers think that light smoking or smoking for a short period of time doesn’t carry any risks.” Yet it is understood that even occasional tobacco consumption increases mortality.
This was not the only misconception regarding smoking and its relationship with cancer. About 34% of survey respondents agreed with the following statement: “Smoking doesn’t cause cancer unless you’re a heavy smoker and have smoked for a long time.” Furthermore, 43.3% agreed with the statement, “Pollution is more likely to cause cancer than smoking,” 54.6% think that “exercising cleans your lungs of tobacco,” and 61.6% think that “a smoker can prevent developing cancer caused by smoking if they know to quit on time.”
Overweight and obesity
Although diet and excess weight represent the third and fourth biggest avoidable cancer risk factors, after smoking and alcohol, only 30% of survey respondents knew of this link.
“Among the causes of cancer known and cited by respondents without prompting, excessive weight and obesity were mentioned only 100 times out of 12,558 responses,” highlighted the authors of the report. The explanation put forward by the authors is that discourse about diet has been more focused on diet as a protective health factor, especially in preventing cardiovascular diseases. “The link between cancer and diet is less prominent in the public space,” they noted.