Low-Grade Intramedullary Spinal Cord Tumors in Adults: A Population- Based Analysis of Clinicopathologic Features and Survival

Abstract Low-grade intramedullary spinal cord tumors are rare and heterogeneous neoplasms, with survival influenced by tumor grade, histology, and treatment. Contemporary population-based analyses are limited. This study evaluated prognostic factors for overall survival (OS) and disease-specific survival (DSS) in adults with low-grade spinal cord tumors. We conducted a retrospective cohort study using SEER data (1975–2022) that included 2,261 adults with WHO Grade I–II intramedullary spinal cord tumors. Demographic, clinicopathologic, and treatment variables were analyzed. Kaplan–Meier analyses estimated OS and DSS, and Cox proportional hazards models assessed prognostic factors. The mean age was 47.6 ± 16.0 years; 80.0% were White. Ependymoma NOS (60.1%) and astrocytoma NOS (24.4%) were the most common tumors. Surgery was performed in 85.7% of patients; radiotherapy and chemotherapy were used in 28.6% and 3.9%, respectively. Median survival was 144 months, with 73.2% surviving > 75 months. Grade II and infiltrative astrocytic subtypes were associated with worse OS and DSS. Lack of surgery, older age, male sex, Black race, lower household income, and receipt of radiotherapy or chemotherapy were independently linked to poorer survival. Tumor grade and surgical resection are the strongest determinants of survival in adult low-grade intramedullary spinal cord tumors. Histology, age, sex, race, and socioeconomic status further affect the clinical outcomes. These results support individualized, risk-adapted management strategies and underscore the need for integrating molecular profiling to improve prognostication and guide therapy in this rare population.