Adult primary high-grade spinal glioma: a nationwide analysis of current trends in treatment and outcomes.

Purpose: High-grade spinal glioma (HGSG) is an extremely rare, malignant neoplasm insufficiently described in the literature. We sought to investigate the effect of epidemiological risk factors and treatment strategies on the prognosis of HGSGs using the National Cancer Database (NCDB).
Methods: Patients with diagnosis codes specific for HGSG were queried from the NCDB during the years 2004-2016. Kaplan-Meier curves were generated with log-rank testing performed to assess factors affecting survival. Univariate and multivariate Cox regression analysis was also performed to investigate overall survival.
Results: 396 patients were identified with a histologically-confirmed diagnosis of HGSG between 2004-2016. The mean survival time for all patients was 24.5 months (SD: 20.3). Multivariate Cox proportional-hazards regression analysis revealed that tumor size of 26-50 mm (HR 4.96, 95% CI 1.76-13.98, p < 0.01) and greater than 50 mm (HR 4.67, 95% CI 1.43-15.23, p = 0.01) were associated with worsened overall survival in comparison to lesions less than 26 mm. While quality of life was not investigated, both Kaplan-Meier log-rank testing and regression analysis failed to demonstrate an association of survival outcomes with extent of resection, radiotherapy, or chemotherapy.
Conclusion: The current study represents the largest retrospective analysis of adult primary high-grade spinal glioma to date. Our analysis found no relationship between the extent of surgical resection and survival outcomes. In addition, we failed to show any statistically significant survival benefit with radiotherapy or chemotherapy. This disease process has a poor prognosis without a current modality of treatment that improves survival.