Canadian Cancer Statistics 2006: Cancer screening in Canada not realizing full potential
11 April 2006
Fewer Canadians would die from cancer if cancer screening in Canada was enhanced and expanded, according to a special report in Canadian Cancer Statistics 2006 released today by the Canadian Cancer Society.
The report also states that some screening tests can help prevent cancer (e.g., cervical and colorectal cancers) as they detect pre-cancerous conditions, which can then be treated or removed.
“We have solid scientific evidence that screening through an organized program can reduce cancer deaths and, in some cases, even the incidence of certain cancers,” says Heather Logan, Director, Cancer Control Policy, Canadian Cancer Society. “Existing cancer screening has helped reduce the cancer toll in Canada. However, we need to do more to make the most of this opportunity, which has the potential to significantly reduce the cancer burden in this country.”
The special report – Progress in Cancer Control: Screening – says that cancer screening in Canada is not reaching its full potential because:
- participation in existing cervical and breast cancer screening programs need to be enhanced. Barriers have to be identified so that effective methods to reach out to women can be developed.
- an organized colorectal cancer screening program has not been implemented in any province or territory in Canada, despite scientific evidence showing it would be an effective way to reduce both incidence and death of this common cancer.
In addition, the special report states more research is needed to identify effective screening tests for prostate, lung and ovarian cancers.
Screening is the early detection of cancer by testing or checking for disease in people who don’t show any symptoms of the disease. Detecting cancer early usually improves the likelihood of successful treatment, which leads to fewer Canadians dying from the disease. Screening can also help prevent some cancers by detecting pre-cancerous stages of the disease.
Current evidence suggests that breast cancer deaths could be reduced by as much as one-quarter if 70 per cent of women in the target age group (50-69 years) participated in organized screening programs. Every province and territory (except Nunavut) had an organized breast-screening program by 2003. However, none of the organized programs have achieved the nationally established target of 70 per cent participation.
“While it’s encouraging that the proportion of women in organized breast cancer screening programs has increased over time, in 2003 participation was only 34 per cent nationally,” says Logan.
The special report also says that about 61 per cent of Canadian women reported having a screening mammogram within two years. This is likely because mammography is also available through centres not affiliated with organized programs.
“The percentage of women who have been screened is probably somewhere between 34 and 61 per cent, and this is too low,” says Logan. “However, breast cancer death rates have been declining and screening is one reason for this downward trend.”
The Canadian Cancer Society recommends that women between the ages of 50 and 69 have a screening mammogram and a clinical breast exam every two years.
Women report that barriers to screening include not have a regular doctor or living in rural areas. “It’s important to understand the barriers so that effective methods to reach out to women can be developed. For example, for women living in rural areas, a portable mammography unit may encourage women to get screened,” says Logan
In Canada, scientific evidence shows that colorectal cancer deaths could be reduced by 17 per cent if 70 per cent of Canadians between the ages of 50 and 74 had a fecal occult blood test (FOBT) every two years.
“This is a potentially significant drop in deaths from colorectal cancer,” says Logan. “Although some informal screening is taking place, there is no organized colorectal screening program in Canada.”
In addition, FOBT screening could have an impact on incidence of colorectal cancer as this test can detect blood in the stool from pre-cancerous polyps. Once identified, these polyps can be removed by colonoscopy or sigmoidoscopy before they become cancerous.
Largely as a result of “ad-hoc” (not organized) screening for cervical cancer with the Pap test, incidence rates have declined by 50 per cent and death rates by 60 per cent since 1977. The Pap test can identify pre-cancerous lesions that can then be treated, and can identify cancer at an early stage when treatment is most effective.
“Because of the long history of high-quality cervical cancer screening in Canada, the benefit achieved so far may be close to the maximum,” says Logan. “However, it might be possible to see even further reductions in both incidence and death for this cancer if all elements of an organized screening program are incorporated, which would include identifying opportunities to increase participation.”
The special report says that screening in Canada could be enhanced and improved if:
- Canada’s capacity to review scientific evidence about screening was strengthened so that appropriate health policy recommendations could be developed in a timely fashion;
- adequate funding and support was provided for screening programs that scientific evidence show are effective at reducing cancer death rates;
- more research was done to identify screening tests for those cancers for which there is not yet sufficient evidence to support an organized cancer screening program (for example, the prostate specific antigen [PSA] test for prostate cancer and CT scans for those at high risk of lung cancer).
“Many Canadians have been touched personally by cancer, and millions more have supported friends and family members in their fight against this devastating disease,” says the Honourable Tony Clement, Minister of Health. “This is why the Government of Canada is committed to implementing a five-year Canadian Strategy for Cancer Control.”
“We recognize the enormous contribution the Canadian Cancer Society and others in the cancer community have made,” he adds. “We are proud to again partner with them in developing this report, and we are pleased to continue our work with the provinces and territories on national quality standards and targets for cancer screening programs.”
If funding is allocated from provincial governments, implementing organized cancer screening programs is the responsibility of provincial cancer agencies (not every province has a cancer agency). The federal government is supportive of the development of screening policies and guidelines.
“Achieving maximum benefit from cancer screening across Canada requires continued work by all levels of government, cancer organizations, experts and Canadians,” says Logan. “The Canadian Strategy for Cancer Control provides an effective mechanism to bring these groups together so this important issue can be dealt with in a coordinated and collaborative way. By working together we can identify gaps, develop ways to provide more opportunity for people to get screened, and target funding to areas with the most need.
“The Canadian Cancer Society is looking forward to working with the government to implement this important health initiative for Canadians.”
For individual Canadians, Logan urges them to take full advantage of current cancer screening programs. “Talk to your doctors about what cancer screening tests are best for you,” says Logan. “It could save your life.”
Logan adds that the Society will continue its work in developing screening recommendations, getting this information to Canadians, and advocating governments to ensure appropriate screening programs are implemented.
Screening is delivered in two ways in Canada – through organized programs or through what is called “ad-hoc” screening. Screening is most effective and cost-efficient when offered through an organized screening program. There are defined elements for an organized program, which include follow-up guidelines, recruitment strategies, and monitoring and evaluation. Ad-hoc screening may include some of these elements, but not all.
The Canadian Strategy for Cancer Control is a blueprint for a coordinated, comprehensive approach to managing cancer in Canada. If implemented, the Strategy will prevent new cancer cases, reduce disability, suffering and death from the disease, and minimize the social and economic impacts of cancer. It will enable cancer experts, health professionals and individuals to manage cancer effectively and efficiently across Canada and in local communities.
Canadian Cancer Statistics 2006 is prepared, printed and distributed through a collaboration of the Canadian Cancer Society, the Public Health Agency of Canada, the National Cancer Institute of Canada, Statistics Canada, provincial/territorial cancer registries, as well as university-based and provincial/territorial cancer agency-based cancer researchers.
The Canadian Cancer Society is a national community-based organization of volunteers whose mission is to eradicate cancer and to enhance the quality of life of people living with cancer. When you want to know more about cancer, visit our website www.cancer.ca or call our toll-free, bilingual Cancer Information Service at 1 888 939-3333.