Stomach Cancer Incidence and Mortality Trends among Circumpolar Nations

Cancer Epidemiol Biomarkers Prev. 2021 Feb 24:cebp.1618.2020. doi: 10.1158/1055-9965.EPI-20-1618. Online ahead of print.


BACKGROUND: Stomach cancer incidence and mortality rates are declining across circumpolar nations, but the burden may not be distributed equally across sub-populations, including Indigenous peoples. Our objective was to examine stomach cancer incidence and mortality trends across circumpolar populations.

METHODS: Cancer incidence and mortality data from 1999-2016 were obtained from the Canadian Cancer Registry, Canadian Vital Statistics, CDC WONDER, NORDCAN, Northwestern Russian cancer registries and National Cancer Reports. The direct method was used to calculate ten-year rolling age-standardized incidence and mortality rates to the World (WHO 2000-2025) and 2011 Canadian standard populations. Standardized incidence rate ratios (SRRs) were calculated. Data were stratified by sex, year and region. US data were broken down by race (White; American Indian/Alaska Native (AIAN)). Race data were not available from non-US cancer registries.

RESULTS: Most populations showed declining incidence and mortality rates over time. Incidence rates among Greenland males and females, Alaska AIAN males and females, and Northern Canadian both sexes were elevated compared to regional counterparts and remained stable. The largest male SRR was observed among Alaska AIAN versus Alaska Whites (SRR=3.82, 95% CI=2.71-5.37). The largest female SRR was observed among Alaska AIAN versus Alaska Whites (SRR=4.10, 95% CI=2.62-6.43).

CONCLUSIONS: Despite stomach cancer incidence and mortality rates declining overall, some northern and Indigenous populations experience elevated and stable incidence and mortality rates.

IMPACT: There is a need to address disparities observed among circumpolar sub-populations. Given similarities in incidence, mortality and risk factor prevalence across circumpolar regions, addressing disparities could benefit from coordinated international action.

PMID:33627381 | DOI:10.1158/1055-9965.EPI-20-1618