Although March is Colorectal Cancer Awareness Month, there is reason to think about this deadly disease year-round.
“Colorectal cancer is the second-leading cause of cancer deaths in Canada (next to lung cancer), yet it is almost entirely preventable,” says Dr. Steven Gallinger, staff surgeon at Mount Sinai Hospital and a senior scientist at the Samuel Luenfeld Research Institute.
According to the Canadian Cancer Society, colorectal cancer is 90 per cent treatable if detected early and only 10 per cent treatable if detected in later stages. This year an estimated 3,100 people in Ontario will die of colorectal cancer and 7,500 will be diagnosed with the disease.
Gallinger explains that the number of deaths from the disease should ultimately be much lower, since colorectal cancer is the only major cancer where screening can identify risk even before the disease is present. “We can detect polyps before they become cancerous,” he says. “We can save more lives if, by age 50, everyone starts doing something to prevent colorectal cancer.”
A colonoscopy is the best test to detect polyps and cancers; however there are not enough resources to test every single adult in Ontario. Gallinger suggests a fecal occult blood test as an effective alternative for all adults. A colonoscopy involves examining the inner surface of the colon with a visual scope. Fecal occult blood testing, on the other hand involves chemical analysis of a stool sample to detect hidden blood – a sign of disease risk.
“Everyone should at least be screened every one to two years by a family physician with the fecal occult blood test,” says Gallinger. “Those with a higher genetic risk should then have a colonoscopy performed on a regular basis. Everyone is at some risk, although the degree of risk varies based on genetic and environmental factors. Genetic counseling and testing is available in Ontario for those with strong family histories.”
Dr. Gallinger is leading research into the inherited and acquired molecular aspects of colorectal cancer. His laboratory is also conducting similar research relating to pancreatic cancer. This research is translating into improved care for patients with colorectal cancer.
“We are getting better at testing for this cancer and also at treating it,” Gallinger says. “New chemotherapy treatments are more effective and surgery is safer and more successful. As well, genetic testing is getting very accurate at determining a person’s risk of developing the disease.”
Although advances in treatment for patients might ultimately reduce the mortality rate of colorectal cancer, the emphasis should still be on prevention through testing and eliminating environmental risk factors. These include unhealthy diets, obesity, lack of exercise and smoking.
“The fact is that the risk of colorectal cancer is under-appreciated,” says Gallinger. “That is partly why the number of deaths from this largely preventable cancer is so high. Everyone needs to understand the benefit of a healthy lifestyle and proper screening.”