Lung cancer in Nunavik: How are we doing? A retrospective matched cohort study.

Background: Whether Inuit in Canada experience disparities in lung cancer survival remains unknown. When requiring investigation and treatment for lung cancer, all residents of Nunavik, the Inuit homeland in Quebec, are sent to the McGill University Health Centre (MUHC), in Montréal. We sought to compare survival among patients with lung cancer at the MUHC, who were residents of Nunavik and Montréal, Quebec, respectively.

Methods: We conducted a retrospective cohort study. Using lung cancer registry data, we identified Nunavik residents with histologically confirmed lung cancer diagnosed between 2005 and 2017. We aimed to match 2 Montréal residents to each Nunavik resident on sex, age, calendar year of diagnosis, and histology (non-small cell lung cancer v. small cell lung cancer). We reviewed medical records for data on additional patient characteristics and treatment, and obtained vital status from a provincial registry. We compared survival using Kaplan-Meier analysis and Cox proportional hazards regression.

Results: We included 95 residents of Nunavik and 185 residents of Montréal. For non-small cell lung cancer, median survival times were 321 (95% confidence interval [CI] 184-626) days for Nunavik ( = 71) and 720 (95% CI 536-1208) days for Montréal residents ( = 141). For small cell lung cancer, median survival times were 190 (95% CI 159-308) days for Nunavik ( = 24) and 270 (95% CI 194-766) days for Montréal residents ( = 44). Adjusting for matching variables, stage, performance status, and comorbidity, Nunavik residents had a higher hazard of death (hazard ratio 1.68, 95% CI 1.17-2.41).

Interpretation: Nunavik residents experience disparities in survival after lung cancer diagnosis. Although studies in other Inuit Nunangat regions are needed, our findings point to an urgent need to ensure that interventions aimed at improving lung cancer survival, including lung cancer screening, are accessible to Inuit Nunangat residents.