Association between urbanicity and surgical treatment among patients with primary glioblastoma in the United States

Racial and socioeconomic disparities in glioblastoma outcomes: A single-center, retrospective cohort study

BACKGROUND

Glioblastoma (GBM) is the most common malignant primary brain tumor. Emerging reports have suggested that racial and socioeconomic disparities influence the outcomes of patients with GBM. No studies to date have investigated these disparities controlling for isocitrate dehydrogenase (IDH) mutation and O-6-methylguanine-DNA methyltransferase (MGMT) status.

METHODS

Adult patients with GBM were retrospectively reviewed at a single institution from 2008 to 2019. Univariable and multivariable complete survival analyses were performed. A Cox proportional hazards model was used to assess the effect of race and socioeconomic status controlling for a priori selected variables with known relevance to survival.

RESULTS

In total, 995 patients met inclusion criteria. Of these, 117 patients (11.7%) were African American (AA). The median overall survival for the entire cohort was 14.23 months. In the multivariable model, AA patients had better survival compared with White patients (hazard ratio [HR], 0.37; 95% confidence interval [CI], 0.2-0.69). The observed survival difference was significant in both a complete case analysis model and a multiple imputations model accounting for missing molecular data and controlling for treatment and socioeconomic status. AA patients with low income (HR, 2.17; 95% CI, 1.04-4.50), public insurance (HR, 2.25; 95% CI, 1.04-4.87), or no insurance (HR, 15.63; 95% CI, 2.72-89.67) had worse survival compared with White patients with low income, public insurance, or no insurance, respectively.

CONCLUSIONS

Significant racial and socioeconomic disparities were identified after controlling for treatment, GBM genetic profile, and other variables associated with survival. Overall, AA patients demonstrated better survival. These findings may suggest the possibility of a protective genetic advantage in AA patients.

PLAIN LANGUAGE SUMMARY

To best personalize treatment for and understand the causes of glioblastoma, racial and socioeconomic influences must be examined. The authors report their experience at the O'Neal Comprehensive Cancer Center in the deep south. In this report, contemporary molecular diagnostic data are included. The authors conclude that there are significant racial and socioeconomic disparities that influence glioblastoma outcome and that African American patients do better.

Racial/ethnic disparities in treatment pattern and time to treatment for adults with glioblastoma in the US

PURPOSE

Race/ethnicity have been previously shown to significantly affect survival after diagnosis with glioblastoma, but the cause of this survival difference is not known. The aim of this study was to examine variation in treatment pattern and time to treatment by race/ethnicity, and the extent to which this affects survival.

METHODS

Data were obtained from the National Cancer Database (NCDB) for adults ≥ 40 with glioblastoma from 2004 to 2016 (N = 68,979). Treatment patterns and time to treatment by race/ethnicity were compared using univariable and multivariable logistic and linear regression models, respectively, and adjusted for known prognostic factors and factors potentially affecting health care access.

RESULTS

Black non-Hispanics (BNH) and Hispanics were less likely to receive radiation and less likely to receive chemotherapy as compared to White non-Hispanics (WNH). Time to radiation initiation was ~ 2 days longer and time to chemotherapy initiation was ~ 4 days longer in both groups in comparison to WNH.

CONCLUSION

Both race/ethnicity and treatment timing significantly affected survival time, and this association remained after adjustment for known prognostic factors. Additional research is necessary to disentangle the specific causal factors, and the mechanism with which they affect survival.