Temporal changes in rural-urban treatment patterns for early-stage non-small cell lung cancer in North Carolina, 2006 to 2015.
112 Background: Rural-urban disparities in the receipt of surgery for early-stage non-small cell lung cancer (NSCLC) have been noted, but few studies have considered access to other available treatments (i.e. radiation) or examined changes over time. Rural hospital closures, regionalization and workforce changes could lead to temporal changes in treatment access. Therefore, the primary objective was to evaluate geographic disparities in lung cancer treatment modalities in North Carolina and to characterize how practice patterns are changing over time. We hypothesized that rural patients would be less likely to undergo treatment compared to urban patients with widening disparities over time. Methods: North Carolina cancer registry data linked with Medicaid, Medicare, and private insurance claims were used to identify patients with Stage I or II NSCLC from 2006-2015. The primary outcome was first course treatment modality: surgery, radiation, or no treatment. Rural-urban status was defined based on Rural-Urban Commuting Codes. Calendar years were split into early (2006-10) and late (2011-15) periods. Multivariable logistic regression was used to assess the association of rural/urban status and time period with surgery and any treatment (surgery or radiation) while controlling for clinical, demographic, and area-level factors. Results: Among 7532 patients, 4144 (56%) patients underwent surgery, 1991 (27%) received radiation, and 1397 (19%) had no therapy. Rural patients were as likely to undergo treatment in either time period as urban patients. Among rural patients, the odds of surgery decreased over time (2011-15 vs. 2006-10 OR 0.79, 95%CI 0.66,0.94) and the odds of radiation increased (2011-15 vs. 2006-10 OR 1.46, 95%CI 1.40,1.78). Meanwhile urban patients had no significant change in surgery over time, but also had an increase in likelihood of undergoing radiation (2011-15 vs. 2006-10 OR 1.34 95%CI 1.18,1.52). Conclusions: Between 2006-2015, nearly 1 in 5 insured patients in North Carolina did not receive any treatment for potentially curable lung cancer. Over time, rural patients are less likely to undergo surgery, the standard of care, while radiation use is increasing everywhere. As rural patients are less likely to undergo surgery over time, this may have downstream effects on rural-urban disparities in survival. Further work aims to understand the patient and system level drivers behind these trends.