Disparities in utilization of treatment for clinical stage I-II pancreatic adenocarcinoma by area socioeconomic status and race/ethnicity.

Background: Utilization of multimodality therapy for clinical stage I-II pancreatic ductal adenocarcinoma is associated with meaningful prolongation of survival. Although the qualitative existence of disparities in treatment utilization by socioeconomic status and race/ethnicity is well documented, the absolute magnitudes of these disparities have not been previously quantified.

Methods: The exposures in this retrospective cohort study of the 2010-2015 National Cancer Database were a 7-value area-level socioeconomic status index and race/ethnicity. Main outcomes were surgery, chemotherapy, and multimodality therapy (surgery and chemotherapy). Adjusted rate differences were calculated after logistic regression. Models excluded intermediate variables. Overall survival was evaluated in unadjusted and adjusted analyses.

Results: Of 43,760 patients, 63.4% underwent surgery. Of 39,808 patients without chemotherapy contraindications, refusal, or missing data, 75.1% received chemotherapy and 51.4% received multimodality therapy. Adjusted rate differences for utilization of surgery, chemotherapy, and multimodality therapy in the lowest socioeconomic status patients were -10.0 (95% confidence interval [CI] -12.4 to -7.5), -12.7 (95% CI -16.3 to -9.1), and -15.4 (95% CI -18.8 to -12.0), respectively, versus the highest socioeconomic status patients. Adjusted rate differences for multimodality therapy utilization in non-Hispanic Black and Hispanic patients were -10.1 (95% CI -13.6 to -6.7) and -11.8 (95% CI -14.3 to -9.2), respectively, versus non-Hispanic White patients. Median overall survival increased in a graded fashion from 14.1 (95% CI 13.4-14.8) months in the lowest socioeconomic status patients to 20.2 months (95% CI 19.6-20.8) in the highest socioeconomic status patients. Survival differences were attenuated but not eliminated in multivariable Cox models.

Conclusion: Socioeconomic status and race/ethnicity are more powerful determinants of whether patients receive treatment for clinical stage I-II pancreatic ductal adenocarcinoma than previously appreciated. Nationwide quality improvement efforts aimed at addressing these inequities are warranted.