Comparing stage of diagnosis of cervical cancer at presentation in immigrant women and long-term residents of Ontario: a retrospective cohort study

BACKGROUND: Globally, cervical cancer is the fourth most common cancer in women and 7th most common cancer overall. Cervical cancer is highly preventable with screening. Previous work has shown that immigrants are less likely to undergo screening than nonimmigrants in Ontario, Canada. We examined whether immigrant women are more likely to present with later stage cervical cancer than long-term residents of the province. METHODS: We conducted a retrospective matched cohort study of women with cervical cancer diagnosed between 2010 and 2014 using provincial administrative health data. We compared the odds of late-stage diagnosis between immigrants and long-term residents, adjusting for socioeconomic measures, comorbidities and health care use. The outcome of interest was stage of cervical cancer diagnosis, defined as early (stage I) or late (stages II-IV). We confirmed results with a cohort of women with cancer diagnosed between 2007 and 2012. RESULTS: Complete staging data were available for 218 immigrants and 1348 matched long-term residents. We found no association between immigrant status and stage at diagnosis (adjusted odds ratio [OR] 0.94, 95% confidence interval [CI] 0.63-1.39). Factors that did show significant association with late-stage diagnosis were physician characteristics, whether a woman had previously undergone screening and had visited a gynecologist in the past 3 years. These results were echoed in the 2007-2012 cohort (immigrants v. long-term residents, OR 0.94, 95% CI 0.71-1.20). INTERPRETATION: Our results show that being an immigrant is not associated with late-stage diagnosis of cervical cancer in Ontario. Programs broadly aimed at immigrants may require a targeted approach to address higher-risk subgroups.