482 Socioeconomic Disparities in the Treatment of Skull Base Chordoma: A National Cancer Database Analysis

INTRODUCTION: Chordomas of the skull base are exceedingly rare tumors associated with insidious onset of symptoms and a high rate of local recurrence. While management is commonly centered around surgical resection and adjuvant radiotherapy, the factors influencing postoperative prognosis remain unclear. METHODS: The NCDB was searched to identify all cases of skull base chordoma treated with surgery and radiotherapy between 2004–2017. Patient data including race, insurance status, education, income, comorbidity status, and surgical details were extracted. The main outcome of interest was 5-year mortality. Survival analyses were performed using Kaplan-Meier plots stratified by socioeconomic variables. Decision tree and random forest models to predict mortality were trained and validated using unseen data with an 80/20 split. RESULTS: A total of 727 patients were included in the study. The mean age was 46.7 ± 19, and 46.4% of patients were female. Most patients were treated at an academic or research hospital (85.3%) and resided in a metropolitan area (88.6%). The majority of the study cohort self-identified as White (72.8%). Private insurance, highest income quartile, treatment at an academic/research facility, and metropolitan residence significantly improved survival (p < 0.001). Race, sex, and education status did not impact survival. The trained decision tree model was able to predict 5-year mortality with 82.8% accuracy in the test cohort. On minimal depth analysis, age, insurance status, and income were the most important variables in predicting 5-year mortality. CONCLUSIONS: Insurance, income, facility type, and rurality were associated with significant differences in overall survival following surgery and radiotherapy for skull base chordoma. These findings may represent disparities in treatment and access to care resulting in inequities experienced by patients in the management of skull base chordoma.