Study reveals latest cancer trends in Canada

Canadian Medical Association JournalMay 13 2024

The number of cancer cases and deaths in Canada is expected to increase because of a growing and aging population, but the overall rates of people being diagnosed with and dying from cancer will continue to decline, according to the latest cancer trends research in CMAJ (Canadian Medical Association Journal) https://www.cmaj.ca/lookup/doi/10.1503/cmaj.240095.

The study is the result of a collaboration between the Canadian Cancer Society, Statistics Canada, and the Public Health Agency of Canada. It provides estimates of the number and rate of new cancer cases and deaths in 2024 for 23 cancer types by province or territory, and sex. This is a major update with the inclusion of data from Quebec that provides more accurate national estimates.

Cancer has a major impact on the people and the economy of Canada. These estimates highlight where progress has been made to reduce those impacts, and where more attention and resources are needed." 

Dr. Darren Brenner, lead author, epidemiologist and associate professor at the Cumming School of Medicine, University of Calgary

When adjusting for our aging population, overall incidence and mortality rates are projected to decrease slightly from previous years for both males and females, and are projected to continue to decrease for some of the most common cancers, including lung, colorectal, and prostate. Meanwhile, incidence rates of cancers that are less common, including liver and intrahepatic bile duct cancer, kidney cancer, melanoma, and non-Hodgkin lymphoma, are projected to increase.

Key points:

• Cancer is still the number one cause of death in Canada (about 25% in 2022)
• It is projected there will be 247 100 new cancer diagnoses and 88 100 cancer deaths in 2024. This is up from an estimated 239 100 cancer cases and 86 700 cancer deaths in 2023
• Lung cancer is projected to be the most diagnosed cancer, with 32 100 new cases, and remains the leading cause of cancer death for both males and females in 2024 (20 700)
• Breast (30 800 cases), prostate (27 900), and colorectal (25 200) cancers are projected to be the next most common cancers
• The top four cancers (lung, breast, prostate, and colorectal) are expected to make up almost half (47%) of all new cases
• Rates of cancer mortality are higher in eastern Canada compared with western Canada
• Cancer mortality rates are expected to be 37% higher in males than in females
• More people are surviving cancer, with an estimated 1.5 million in Canada living with and beyond cancer 25 years after diagnosis

The authors adjusted for differences in ages to ensure comparisons across populations with different age structures (age-standardized incidence rate). The term "age-standardized" refers to a statistical approach that allows for comparison between populations with different age structures and population sizes, as well as comparisons over time.

"This growing population of cancer survivors, combined with the projected annual increase in the total number of new primary cancers in 2024, will have a substantial impact on Canadian health care systems, given ongoing needs of people with a history of cancer," write the authors. "The increase in the number of cancer survivors will require both additional investment and innovation to provide necessary supports."

The authors provide projected rates and counts of new cancer cases by region and cancer type in Appendix 2.

"The 2024 cancer projections tell a complex story, one where we can point to progress among some of the most common cancer types, but also where those less common cancers are projected to increase," says Dr. Jennifer Gillis, senior manager of surveillance at the Canadian Cancer Society and coauthor of the study. "While the overall cancer incidence rate continues to decline, likely due to continued efforts in cancer prevention and screening, it's concerning to see incidence rates of certain cancers like liver, kidney, melanoma, head and neck, and non-Hodgkin lymphoma on the rise. It tells us we need to continue to research these areas and push for public policies that will help drive those rates back down."

In a related editorial https://www.cmaj.ca/lookup/doi/10.1503/cmaj.240612, Dr. Keerat Grewal, a clinician scientist at the Schwartz/Reisman Emergency Medicine Institute at Sinai Health, Toronto, and Dr. Catherine Varner, deputy editor, CMAJ, write, "Receiving a diagnosis of cancer in an emergency department is becoming routine in Canada, which highlights the failure of health care systems to support adequate primary care–initiated pathways for diagnosis of suspected cancer. One in 5 people in Canada do not have a regular primary care provider and, even among those who do, many report poor access to primary care."

They suggest expanding access to outpatient clinics that streamline suspected cancer diagnoses, like Ontario's diagnostic assessment program clinics, and offering navigation support for patients discharged from the emergency department with a cancer diagnosis.

"Continued efforts to increase awareness of early cancer symptoms, reduce barriers to cancer screening, and increase capacity for its early diagnosis in primary care and hospitals are critical. To lose the gains made in cancer outcomes to the overcrowding, fragmentation, and inefficiencies of health care systems would be a tragic shame," conclude Drs. Grewal and Varner.