Do cancer incidence and mortality rates differ among ethnicities in Canada?

Background: Cancer incidence rates have been shown to vary by ethnicity, and the increasing awareness of and interest in reporting ethnic health inequalities have been growing internationally. The objective of this study was to assess cancer incidence and mortality rates by ethnicity in Canada.

Data and methods: The study used the 2006 Canadian Census Health and Environment Cohort, linked to the Canadian Cancer Registry and the Canadian Vital Statistics-Death Database, to determine cancer cases and mortality from 2006 to 2016. Ethnicity was categorized as non-Indigenous North American (NINA); European; Caribbean; Latin, Central and South American (LCSA); African; East Asian; South Asian; and West Central Asian and Middle Eastern.

Results: Europeans had the highest standardized incidence rates, while NINA had the highest mortality rates. Rates varied substantially by ethnicity and immigrant status. The top three cancers accounted for 46.5% to 61.9% of all new cancers, while the top three cancer deaths accounted for 36.1% to 61.9% of all deaths. The distribution of cancers within the top 10 cancers and the top 10 cancer deaths also differed; e.g., stomach cancer was found to be more prevalent in the East Asian, LCSA, African and Caribbean groups. Non-immigrant African males had the highest cancer incidence rates, and non-immigrant South Asian females had the highest mortality rates.

Discussion: There is considerable variability in cancer incidence and cancer mortality rates by ethnicity, and this study addresses the knowledge gap in Canada in this area. Establishing baseline indicators, such as cancer rates by ethnicity, is essential to understanding the differences within the diverse Canadian population and to informing targeted interventions that may help reduce health inequalities.