Management, outcomes, and prognostic factors of adult primary spinal cord gliomas

Purpose: Primary spinal cord tumors are rare, particularly in the adult population, and national guidelines remain ambiguous with regard to management approaches. To address this knowledge gap, we evaluated management, outcomes, and prognostic factors of these neoplasms. Methods: The National Cancer Database was queried (2004–2016) for newly-diagnosed, histologically-confirmed WHO grades I-III astrocytomas and glioblastoma. Statistics included Kaplan-Meier overall survival (OS) analysis, along with Cox proportional hazards modeling. Results: Of 1,033 subjects, 196 (19%) were pilocytic astrocytomas (PAs), 539 (52%) were grade II/III astrocytomas, and 298 (29%) were glioblastomas (GBMs). Respectively, 11%, 30%, and 27% did not undergo resection (biopsy only). RT was delivered to 27%, 54%, and 73%; chemotherapy was given to 5%, 21%, and 37%, respectively. The median OS was not reached for PAs, but was 101.2 months for grade II/III astrocytomas, and 23.9 months for GBMs (p < 0.001). Neither chemotherapy nor RT (or dose thereof) was associated with increased OS for grade II/III astrocytomas (p > 0.05 for all), though there was a trend toward improved OS with the use of chemotherapy for patients with GBM. Surgical resection was associated with improved OS for grade II/III astrocytomas and GBM (p < 0.05). Independent prognostic factors for survival in this cohort included histologic classification and resection (compared to biopsy only) (p < 0.05 for both). Conclusions: This study sheds light onto the management of these rare tumors; surgery was associated with OS benefit for patients with GBM and Grade II/III astrocytomas. Neither RT nor chemotherapy were associated with OS benefit. Although not implying causation, these data can be used to guide patient counseling and therapeutic approaches.