The Relationship Between Hospital Safety-Net Burden on Outcomes for High-Volume Thyroid Cancer Surgeons

Background: Higher center and surgeon volume correspond to better outcomes for patients with thyroid cancer. This study aims to investigate how a hospital's safety-net burden, the proportion of a hospital's patients who are insured by state Medicaid plans or are uninsured, influences the outcomes of high-volume (HV) surgeons. Methods: We performed a retrospective cohort study of all patients who underwent surgery for thyroid cancer in California from 1999 to 2017. We stratified treating facilities by the proportion of Medicaid-type and indigent payors into safety-net burden quartiles. We compared the perioperative and oncologic outcomes of HV surgeons (annual case volume ≥10) for patients undergoing total thyroidectomy across safety-net burden quartiles. A mixed-effects regression model controlled for surgeon random effects and fixed effects of patient and tumor characteristics. Results: Our sample comprised 42,347 patients (78% female, median age 50), of whom 13,848 (32%) were treated by HV surgeons (n = 276). Compared to patients of lower-volume surgeons, patients of HV surgeons were more likely to be White, from the upper quartiles of socioeconomic status and well insured (all p < 0.001). HV surgeons in each hospital's safety-net burden quartile displayed similar case number distributions. Compared to patients treated by HV surgeons at Q1 (lowest safety-net burden) hospitals, those treated by HV surgeons at Q4 (highest safety-net burden) hospitals had higher absolute risks of endocrine complications (+7%, p = 0.007), airway complications (+6%, p = 0.004), disease-specific mortality (+1.3%, p = 0.046), and all-cause mortality during the study period (+3%, p = 0.046) in multivariable analysis. Conclusion: The performance of HV thyroid cancer surgeons differs by a hospital's safety-net burden, with patients treated at high safety-net burden hospitals experiencing higher rates of operative complications, disease-specific mortality, and all-cause mortality. Having a HV surgeon alone may be insufficient to provide optimal short- and long-term outcomes for patients with thyroid cancer.