Exploring Social Determinants of Health and Treatment Disparities in Stage I Lung Cancer: Insights from Ontario

An Ontario population-based cohort shows material deprivation is linked to lower receipt of surgical resection and greater reliance on radiotherapy or no treatment among adults with early-stage lung cancer, as reported in the Ontario population-based study. The gap was most pronounced in more deprived neighborhoods and among patients without a rostered family physician—groups who had reduced odds of surgery and increased odds of radiotherapy or no treatment. These differences represent measurable shortfalls in access to guideline-recommended curative surgery and reduce the reach of curative-intent care.

The investigators assembled a population-based retrospective cohort from linked administrative registries and cancer databases at ICES, forming a stage I lung cancer cohort of 19,179 patients diagnosed from 2007–2023. Treatment classification (surgery, radiotherapy, none) was the primary endpoint. Multivariable logistic models adjusted for age, comorbidity, frailty, immigration status, and distance to regional cancer centers, permitting estimation of independent associations between social determinants and treatment selection. The dataset thus yields robust, population-level estimates of how socioeconomic and system factors shape treatment allocation.

After adjustment, neighborhood income and primary-care attachment independently altered treatment likelihoods. Patients in the highest income quintile had higher odds of surgery (adjusted OR ≈1.45) while those in the lowest income quintile were more likely to receive radiotherapy (adjusted OR ≈1.27). Not being rostered with a family physician reduced the odds of surgery (adjusted OR ≈0.59). Recent immigrants showed a mixed pattern—higher odds of surgery but lower odds of radiotherapy—underscoring that social determinants interact in complex ways. Overall, material deprivation and primary-care access remain independent predictors of treatment modality.

Geography produced distinct patterns. Compared with patients living within 50 km of a regional cancer center, those 50–100 km away had lower odds of surgery (adjusted OR ≈0.84) and greater reliance on radiotherapy—consistent with outpatient SBRT being more accessible when travel or inpatient follow-up for surgery is prohibitive. The relationship was non-linear: patients >100 km away were not uniformly less likely to undergo surgery, suggesting selective referral of fitter rural patients able to manage travel. In short, rurality imposes logistic barriers that shift patterns toward SBRT and other non‑surgical approaches.

Key Takeaways:

• Material deprivation and lack of primary-care attachment are independently associated with lower surgical receipt and higher radiotherapy or no-treatment rates in stage I lung cancer.
• Geographic distance (particularly 50–100 km from a regional center) corresponds with reduced surgery and increased reliance on SBRT, reflecting access constraints.
• System levers such as enhancing primary-care pathways and reconsidering regional service distribution are implicated as mechanisms to address these documented disparities.