Abstract PO-094: Socioeconomic status and utilization of cancer surgeries in the United States, Canada, and Australia
Authors: Pang Hilary , Chalmers Kelsey , Landon Bruce , Elshaug Adam , Matelski John , Ling Vicki , Krzyzanowska Monika K. , Kulkarni Girish , Erickson Bradley A. , Cram Peter 
Published: March 2021

Abstract
Background: Few studies have compared surgical oncology utilization between countries or how rates may differ according to patients’ socioeconomic status. This study aimed to compare the utilization rates of three organ resection surgeries predominantly indicated for the treatment of cancer in three jurisdictions in the US, Canada, and Australia, and compare surgical utilization rates between residents of lower- and higher-income neighborhoods. Methods: We used population-based administrative data to identify all adults aged ≥18 years hospitalized for pancreatectomy (PX), radical prostatectomy (RP) and nephrectomy (NX) between 2011-2016 (New York, USA), 2011-2018 (Ontario, Canada), and 2013-2018 (New South Wales, Australia). We linked each patient’s zip-code of residence to 2016 census data to ascertain neighborhood income. We compared utilization rates for each procedure in each jurisdiction in aggregate and by neighborhood income quintile. The primary outcomes were: 1) each jurisdictions’ per-capita overall, age-, and sex-standardized utilization rates for each procedure; and 2) utilization rates amongst residents of lower- and higher-income neighborhoods. Results: Sociodemographics were generally similar across jurisdictions, though patients in New South Wales were slightly older for all procedures. Hospitals in New York were significantly more likely to perform each of the three procedures compared to Ontario and New South Wales (all P&lt;0.001), while New York and New South Wales tended to have more low-volume hospitals relative to Ontario. Overall utilization rate was highest in New York for NX (28.93 procedures per-100,000 per-year) while New South Wales had highest utilization of PX and RP (6.94 and 94.37, respectively); overall utilization of all three procedures was lowest in Ontario (PX 6.18; RP 49.24; NX 21.40; all P&lt;.001). Utilization of PX and NX was significantly higher for men than women in all jurisdictions (all P&lt;0.05). Utilization of all three procedures increased until age 70-79, before declining at age ≥80 (all P&lt;0.001). With the exception of NX in Ontario, residents of lowest income neighbourhoods (quintile 1 [Q1]) had lower surgical utilization rates than residents of highest income neighbourhoods (quintile 5 [Q5]). The Q5-Q1 utilization rate difference was largest in New South Wales for PX and RP (PX +4.65 procedures per-100,000 per-year for Q5 vs Q1; RP +73.46; NX +6.23), largest in New York for NX and smallest for RP (PX +3.05; RP +19.70; NX +8.43) and smallest in Ontario for PX and NX (PX +1.15; RP +27.94; NX -1.10) (all P&lt;0.05). Conclusions: Utilization rates of PX, RP, and NX were significantly higher in New York and New South Wales than in Ontario. Rich-poor surgical utilization differences were significantly larger in New York and New South Wales and significantly smaller in Ontario. These findings suggest that income-based disparities are larger in jurisdictions in the US and Australia and smaller in Canada, and highlight the possible trade-offs of equity and access in healthcare systems of different countries.
Citation Format: Hilary Pang, Kelsey Chalmers, Bruce Landon, Adam Elshaug, John Matelski, Vicki Ling, Monika K. Krzyzanowska, Girish Kulkarni, Bradley A. Erickson, Peter Cram. Socioeconomic status and utilization of cancer surgeries in the United States, Canada, and Australia [abstract]. In: Proceedings of the AACR Virtual Special Conference on Artificial Intelligence, Diagnosis, and Imaging; 2021 Jan 13-14. Philadelphia (PA): AACR; Clin Cancer Res 2021;27(5_Suppl):Abstract nr PO-094.