Brief Report: Impact of PLCOm2012 Ethnicity Model Variations on Eligibility for the Alberta Lung Cancer Screening Program.

Introduction: Screening with low-dose computed tomography reduces lung cancer mortality among individuals at high risk of lung cancer. Three PLCOm2012 model variations for predicting lung cancer risk have been developed: the original model with six race or ethnicity categories (6Race), a model with three race or ethnicity categories (3Race), and a model excluding race and ethnicity (NoRace). We evaluated the impact of model selection on screening eligibility for the Alberta Lung Cancer Screening Program. Methods: Retrospective analysis of 5961 individuals contacting the Alberta Lung Cancer Screening Program. For each participant, we calculated their 6-year risk of lung cancer using the three PLCOm2012 models and compared their eligibility using a 1.5% 6-year lung cancer risk threshold. Results: Of the participants, 70% identified as White, 9% Asian, 4% Indigenous, 0.5% Black, 0.4% Hispanic, and 17% not reported. Furthermore, 67% had a risk more than or equal to 1.5% risk across all three models, whereas 30% had less than 1.5% risk across all models. Using the NoRace model, 31% of Indigenous and 25% of Black individuals were classified below the 1.5% threshold but would have been eligible using 3Race or 6Race. Using the 6Race model, 18% of Asian and 22% of Hispanic individuals were below 1.5% but were above 1.5% in either the NoRace or 3Race model. Conclusions: Choice of PLCOm2012 model can have a considerable impact on screening eligibility, particularly for ethnic minorities. Using the 3Race model increases screening eligibility for Indigenous, Black, Hispanic, and Asian individuals. Canadian-based data validating and quantifying the impact of race and ethnicity on lung cancer risk are urgently needed.