Disparities in access to surgery for glioblastoma multiforme at high-volume Commission on Cancer–accredited hospitals in the United States
Authors: Goyal Anshit , Zreik Jad , Brown Desmond A. , Kerezoudis Panagiotis , Habermann Elizabeth B. , Chaichana Kaisorn L. , Chen Clark C. , Bydon Mohamad , Parney Ian F. 
Published: December 2021

OBJECTIVE
Although it has been shown that surgery for glioblastoma (GBM) at high-volume facilities (HVFs) may be associated with better postoperative outcomes, the use of such hospitals may not be equally distributed. The authors aimed to evaluate racial and socioeconomic differences in access to surgery for GBM at high-volume Commission on Cancer (CoC)–accredited hospitals.

METHODS
The National Cancer Database was queried for patients with GBM that was newly diagnosed between 2004 and 2015. Patients who received no surgical intervention or those who received surgical intervention at a site other than the reporting facility were excluded. Annual surgical case volume was calculated for each hospital, with volume ≥ 90th percentile defined as an HVF. Multivariable logistic regression was performed to identify patient-level predictors for undergoing surgery at an HVF. Furthermore, multiple subgroup analyses were performed to determine the adjusted odds ratio of the likelihood of undergoing surgery at an HVF in 2016 as compared to 2004 for each patient subpopulation (by age, race, sex, educational group, etc.).

RESULTS
A total of 51,859 patients were included, with 10.7% (n = 5562) undergoing surgery at an HVF. On multivariable analysis, Hispanic White patients (OR 0.58, 95% CI 0.49–0.69, p < 0.001) were found to have significantly lower odds of undergoing surgery at an HVF (reference = non-Hispanic White). In addition, patients from a rural residential location (OR 0.55, 95% CI 0.41–0.72, p < 0.001; reference = metropolitan); patients with nonprivate insurance status (Medicare [OR 0.78, 95% CI 0.71–0.86, p < 0.001], Medicaid [OR 0.68, 95% CI 0.60–0.78, p < 0001], other government insurance [OR 0.68, 95% CI 0.52–0.86, p = 0.002], or who were uninsured [OR 0.61, 95% CI 0.51–0.72, p < 0.001]); and lower-income patients ($50,354–$63,332 [OR 0.68, 95% CI 0.63–0.74, p < 0.001], $40,227–$50,353 [OR 0.84, 95% CI 0.76–0.92, p < 0.001]; reference = ≥ $63,333) were also found to be significantly associated with a lower likelihood of surgery at an HVF. Subgroup analyses revealed that elderly patients (age ≥ 65 years), both male and female patients and non-Hispanic White patients, and those with private insurance, Medicare, metropolitan residential location, median zip code–level household income in the first and second quartiles, and educational attainment in the first and third quartiles had increased odds of undergoing surgery at an HVF in 2016 compared to 2004 (all p ≤ 0.05). On the other hand, patients with other governmental insurance, patients with a rural residence, and those from a non-White racial category did not show a significant difference in odds of surgery at an HVF over time (all p > 0.05).

CONCLUSIONS
The present analysis from the National Cancer Database revealed significant disparities in access to surgery at an HVF for GBM within the United States. Furthermore, there was evidence that these racial and socioeconomic disparities may have widened between 2004 and 2016. The findings should assist health policy makers in the development of strategies for improving access to HVFs for racially and socioeconomically disadvantaged populations.