Cancer prevalence, incidence and mortality in people who experience incarceration in Ontario, Canada: A population-based retrospective cohort study

INTRODUCTION Evidence suggests that many risk factors for cancer are overrepresented in people who experience incarceration, and data on cancer epidemiology are limited for this population. We aimed to describe cancer prevalence, incidence and mortality in adults admitted to provincial custody in Ontario, Canada in 2000. METHODS We linked data on 48,166 adults admitted to provincial custody in Ontario in 2000 with Ontario Cancer Registry data to 2012. We calculated cancer prevalence in the 10 years prior to admission to custody in 2000, incidence between 2000 and 2012 and mortality between 2000 and 2011. Standardized for age, we calculated incidence and mortality ratios by sex compared to the general population of Ontario. RESULTS The 10-year cancer prevalence was 0.4% in men and 0.6% in women at admission to provincial custody in 2000. Between 2000 and 2012, 2.6% of men and 2.8% of women were diagnosed with new cancer. The standardized incidence ratio for cancer was 1.0 (95% CI 0.9-1.0) for men and 0.9 (95% CI 0.7-1.0) for women compared to the general population, and was significantly increased for cervical, head and neck, liver and lung cancers. The standardized mortality ratio was 1.6 (95% CI 1.4-1.7) in men and 1.4 (95% CI 1.0-1.9) in women, and was significantly increased for head and neck, liver, and lung cancers. CONCLUSIONS There is an excess burden of cancer in people who experience incarceration. Cancer prevention should include people who experience incarceration, and the period of incarceration may offer an opportunity for intervention.