Overall cancer rates in Canada are declining, but the raw numbers of new cases and deaths each year are projected to increase owing to the country’s growing and aging population, according to a new study that underscores the need for further investments in cancer research and effective public-health policies.
The Canadian Medical Association Journal study, published Monday as a collaborative effort between the Canadian Cancer Society (CCS), Statistics Canada and the Public Health Agency of Canada, projects that there will be 233,900 new cancer cases and 85,100 cancer deaths in 2022 – up from an estimated 229,200 cancer cases and 84,600 cancer deaths in 2021.
The study was released days after Statistics Canada’s 2021 census details showing that the country’s population is aged and aging – with more than one-in-five working-aged people close to retirement age (55 to 64). Aging is a major risk factor for cancer development.
Cancer is the leading cause of death in Canada, and 43 per cent of Canadians are expected to receive a diagnosis in their lifetime, according to the Canadian Cancer Society.
Lung, breast, prostate and colorectal cancers are expected to be the most commonly diagnosed cancers, and together are expected to represent almost half (46 per cent) of all cancers diagnosed in Canada this year, according to the study.
The most diagnosed cancers among those assigned male at birth are projected to be prostate (20 per cent), lung (12 per cent), colorectal (11 per cent) and bladder (8 per cent) cancers. The most diagnosed among those assigned female at birth are projected to be breast (25 per cent), lung (13 per cent), colorectal (10 per cent) and uterine (7 per cent).
Lung cancer is expected to account for one-quarter of all cancer deaths (20,700) in Canada this year, followed by colorectal (9,400), pancreas (5,700), breast (5,500) and prostate (4,600). Together, these are projected to account for 54 per cent of all cancer deaths in the country this year.
Age-standardized rates of incidence and death continue to decline, likely a result of continued effort and investment in cancer prevention, screening and early detection, the authors write. As well, Canadians diagnosed with cancer are seeing an overall increase in survival.
The researchers obtained data on cancer incidence and mortality, as well as population estimates, from the National Cancer Incidence Reporting System, the Canadian Cancer Registry, Canadian Vital Statistics and Statistics Canada. They then projected through to 2022 using a tool called CANPROJ.
Data on cancer cases diagnosed in Quebec from 2011 onward were unavailable as the province had not submitted them to the Canadian Cancer Registry. To account for the lack of Quebec’s numbers, the researchers estimated them by applying rates for the rest of Canada and multiplying by the ratio of sex-, age- and cancer-specific estimates for the province.
Elizabeth Holmes, senior manager of health policy at the CCS and an author of the study, said the projections show that more must be done to prepare for the future impact of cancer in Canada. The CCS is calling on governments to lead a comprehensive and co-ordinated plan that includes investments in research and public-health policies, such as organized screening programs.
“Ways for the health system itself to get ready for this is educating and training human-health resources, and ensuring that we have the infrastructure in place, such as diagnostics facilities in the cancer centres and community-based care, including home and palliative care,” Ms. Holmes said.
The authors highlighted several areas where additional public-health efforts are needed.
“In terms of primary prevention, given steady rising incidence of lung cancer among females before the recent declines, targeted measures to reduce tobacco consumption among younger populations and females remain necessary,” they write.
“In addition, smoking rates are higher among several populations, such as individuals with lower income, those living in rural areas, and First Nations, Inuit and Métis people. Increases in melanoma incidence rates suggest the need for further efforts to reduce ultraviolet exposure and increase sun safety.”
Pancreatic cancer is the 11th most commonly diagnosed cancer and the third most common cause of cancer death in Canada, Ms. Holmes noted.
“It really speaks to the importance of that need for investment into research to improve early detection and treatment for individuals diagnosed with pancreatic cancer,” she said.
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