Canadian Cancer Statistics 2011 released by the Canadian Cancer Society with special focus on colorectal cancer
Use of a simple, at-home screening test by Canadians can prevent many unnecessary colorectal cancer deaths, according to a special report about colorectal cancer in Canadian Cancer Statistics 2011 released today by the Canadian Cancer Society, in collaboration with the Public Health Agency of Canada and Statistics Canada.
If 80% of Canadians aged 50+ were screened over the next 10 years, it is estimated that 10,000 to 15,000 deaths could be prevented.
Colorectal cancer is the second leading cause of cancer death in Canada, with an estimated 8,900 Canadians dying from the disease in 2011. It is the fourth most commonly diagnosed cancer in Canada after prostate, lung and breast cancer. An estimated 22,200 new cases are expected in Canada in 2011. Although rates of colorectal cancer incidence have been declining over the past two decades, the number of new cases has increased substantially due to population growth and aging.
The Society recommends that Canadians aged 50 and over get screened every two years with a simple stool test (known as FOBT or FIT). But currently, only 32% of Canadians in this age group report having a screening test. For people with symptoms or at higher risk of colorectal cancer, it is important that they talk to their doctors.
"One of the major goals of cancer screening is to detect cancer in people who have no symptoms," says Gillian Bromfield, Senior Manager, Cancer Control Policy, Canadian Cancer Society. "For colorectal cancer, screening from age 50 using a stool test leads to fewer deaths. We need to identify and overcome barriers to colorectal cancer screening so that more Canadians get screened regularly. It's a simple test and it saves lives."
The fecal occult blood test (FOBT) and the fecal immunochemical test (FIT) are simple, at-home kits that test for trace amounts of blood in the stool, which can be a sign of colorectal cancer.
"It's very important that doctors talk to their patients about screening," says Bromfield. "Canadians who have discussed colorectal cancer screening with their doctors are more than twice as likely to get screened regularly."
According to the 2009 Colon Cancer Screening in Canada survey, 71.7% of Canadians aged 50 to 74 who discussed colorectal cancer screening with their doctors are up to date with screening, compared to only 32.6% who have not had the discussion.
Some other facts about screening, according to the survey:
- 81% of Canadians are aware that screening tests exist and recognize the benefits of screening.
- 60% of Canadians do not understand that screening is a "health behaviour" that doesn't require symptoms in order to be performed.
- Most Canadians are not familiar with the at-home test. Most are aware of colonoscopy (a more invasive test used for follow-up).
Risk factors and prevention
Risk factors for colorectal cancer include a diet high in red or processed meat, being overweight, physical inactivity, smoking and a family history of the disease. The best ways to reduce the risk of colorectal cancer - along with screening - are eating a healthy diet, being physically active in order to maintain a healthy body weight, not smoking and avoiding excessive drinking.
Diagnosis and treatment
After a positive screening test or symptoms such as bleeding, obstruction or abdominal pain, diagnosis is commonly made using a medical exam such as colonoscopy or sigmoidoscopy.
Treatment depends on the stage at diagnosis and may include surgery, chemotherapy or radiation.
Survival
Compared to other cancers, colorectal cancer has a moderate prognosis with a five-year relative survival rate of 63%. This is better than some cancers, such as lung (16% survival), but worse than prostate (96%) or breast (88%).
Canada has one of the best colorectal cancer survival rates in the world - slightly lower than the US, but better than most of Europe, including the UK and Scandinavia.
The five-year colorectal cancer survival has improved considerably - from 56% in 1992-94 to 63% in 2004-06. Survival is expected to continue to improve in the future as screening uptake increases.
Trends by province
Participation in screening varies widely across the country, with the lowest rate in Quebec and the highest in Ontario and Manitoba (the first two provinces to actively launch province-wide screening programs in 2008 and 2007 respectively).
Conclusions and recommendations
Treatment advances and screening have led to important reductions in colorectal cancer deaths and improvements in survival. However, further improvements will require the following:
- continued emphasis on screening, including:
- more research into the risk factors for colorectal cancer and effective prevention and treatment
"By becoming more aware of colorectal cancer, how to screen for it and how to prevent it, Canadians can help ensure they are looking after themselves and their families," says Dr. David Butler-Jones, Canada's Chief Public Health Officer.
A survivor's story
To her friends, 55-year-old Kavita Jagasia is a walking billboard for the importance of regular colorectal cancer screening.
"Because of what happened to me, now they've all been screened," says Kavita, diagnosed with colorectal cancer in July 2008. "Everybody suddenly woke up."
The Toronto-area account manager in corporate travel was diagnosed after several months of noticing redness in her stool. She told herself it was nothing to worry about, but friends started commenting on her weight loss even though she wasn't dieting. Urged by her husband, she went to her family doctor. A colonoscopy showed she had stage 2 colorectal cancer. Surgery two weeks later removed the tumour and further treatment was not required.
Kavita considers herself lucky, but says a simple screening tool like the fecal occult blood test (FOBT or FIT) could have made much of her experience unnecessary.
People may not want to do it because they think it's "gross," she says, but "if I had done it I probably would have been treated much earlier. I probably would have been treated at the polyp stage, rather than a full-blown cancer."
While a healthy lifestyle may reduce people's cancer risk, Kavita knows that being of normal weight, a vegetarian, non-smoker and non-drinker was not enough to prevent her own cancer.
"If it can happen to me, it can happen to anybody," she says.
General highlights: Canadian Cancer Statistics 2011
- An estimated 177,800 new cases of cancer (excluding 74,100 cases of non-melanoma skin cancer) and 75,000 deaths from cancer are expected to occur in Canada in 2011.
- More men than women are diagnosed with cancer, but the gap between the two sexes has narrowed in recent years (52% of cases are in men versus 48% in women).
- More than one-quarter of all cancer deaths - 27% - are due to lung cancer.
- The death rate for all cancers combined is declining for males in most age groups and for females under 70.
- There were no increases in death rates for most types of cancer in men or women. Notable exceptions include liver (both sexes), lung (women) and melanoma (men).
- The five-year relative survival rate for all cancers combined is 62%.
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