Association of Hospital Flagship System Affiliation on Surgical Outcomes Following Complex Cancer Surgery.

Background: We evaluated variations in patient outcomes and financial expenditures following complex cancer surgery across flagship hospitals and their affiliates.

Methods: Using Medicare 100% Standard Analytic Files (2018-2021), we identified patients undergoing resection of lung, esophageal, gastric, hepatopancreatobiliary, or colorectal cancer. Flagship hospitals were defined as the highest-volume major teaching hospital within a system in each region. Propensity score matching was performed to create a 1:1 matched cohort to assess the association between flagship systems, hospitals, affiliates, and outcomes.

Results: Among 110,670 patients, 55,335 treated within a flagship hospital system (median age, 73 years [IQR, 69-79]; including 29,381 [53.1%] women) were matched with 55,335 patients who were not (median age, 73 years [IQR, 69-79]; including 29,274 [52.9%] women) across 35 regions. Patients at flagship system hospitals had lower 30-day mortality rates than matched controls (4.23% vs 4.88%; difference, -0.65% [95% CI, -0.89% to -0.40%]; P<.001). Mortality was also lower at flagship hospitals (2.76% vs 3.82%; difference, -1.06% [95% CI, -1.62% to -0.50%]) and flagship affiliates (4.46% vs 4.79%; difference, -0.32% [95% CI, -0.58 to -0.07]) compared with controls (both P<.001). However, patients who underwent cancer surgery at flagship hospital systems had higher expenditures ($21,011 vs $20,016; difference, +$995 [95% CI, $797 to $1,193]; P<.001).

Conclusions: Flagship hospitals are the primary drivers of decreased postoperative mortality following complex oncologic surgical procedures performed within their systems, although expenditures were higher compared with unaffiliated hospitals.