Association of Discretionary Hospital Volume Standards for High-risk Cancer Surgery With Patient Outcomes and Access, 2005-2016

Abstract

Various clinical societies and patient advocacy organizations continue to encourage minimum volume standards at hospitals that perform certain high-risk operations. Although many clinicians and quality and safety experts believe this can improve outcomes, the extent to which hospitals have responded to these discretionary standards remains unclear. To evaluate the association between short-term clinical outcomes and hospitals' adherence to the Leapfrog Group's minimum volume standards for high-risk cancer surgery. Longitudinal cohort study using 100% of the Medicare claims for 516 392 patients undergoing pancreatic, esophageal, rectal, or lung resection for cancer between January 1, 2005, and December 31, 2016. Data were accessed between December 1, 2018, and April 30, 2019. High-risk cancer surgery in hospitals meeting and not meeting the minimum volume standards. Patients having surgery in hospitals meeting the volume standard and 30-day and in-hospital mortality and complication rates. Overall, a total of 516 392 procedures (47 318 pancreatic resections, 29 812 esophageal resections, 116 383 rectal resections, and 322 879 lung resections) were included in the study, and patient mean (SD) age was 73.1 (7.5) years. Outcomes improved over time in both hospitals meeting and not meeting the minimum volume standards. Mortality after pancreatic resection decreased from 5.5% in 2005 to 4.8% in 2016 (P for trend <.001). Mortality after esophageal resection decreased from in 6.7% 2005 to 5.0% in 2016 (P for trend <.001). Mortality after rectal resection decreased from 3.6% in 2005 to 2.7 % in 2016 (P for trend <.001). Mortality after lung resection decreased from 4.2% in 2005 to 2.7 % in 2016 (P for trend <.001). Throughout the study period, there were no statistically significant differences in risk-adjusted mortality between hospitals meeting and not meeting the volume standards for esophageal, lung, and rectal cancer resections. Mortality rates after pancreatic resection were consistently lower at hospitals meeting the volume standard, although mortality at all hospitals decreased over the study period. For example, in 2016, risk-adjusted mortality rates for hospitals meeting the volume standard were 3.8% (95% CI, 3.3%-4.3%) compared with 5.7% (95% CI, 5.1%-6.5%) for hospitals that did not. Although an increasing majority of patients underwent surgery in hospitals meeting the Leapfrog volume standards over time, the overall proportion of hospitals meeting the standards in 2016 ranged from 5.6% for esophageal resection to 23.3% for pancreatic resection. Although volume remains an important factor for patient safety, the Leapfrog Group's minimum volume standards did not differentiate hospitals based on mortality for 3 of the 4 high-risk cancer operations assessed, and few hospitals were able to meet these standards. These findings highlight important tradeoffs between setting effective volume thresholds and practical expectations for hospital adherence and patient access to centers that meet those standards.