Institutional Volume Explains Observed Facility-Level Differences in Survival Following Surgical Resection of Spinal Schwannomas: A National Cancer Database Study

Introduction Spinal schwannomas are benign tumors that comprise over 20% of primary intraspinal neoplasms. While gross total resection offers excellent local control, little is known about how facility-level factors correlate with survival. This study evaluated patient and institutional characteristics associated with outcomes in spinal schwannoma surgery. Methods Data were obtained from the National Cancer Database for patients diagnosed with spinal schwannoma. Analyses were performed for the overall cohort and for the subset of patients who underwent surgical resection. Survival outcomes were evaluated using Cox proportional hazards regression. Differences in patient characteristics across facility types were assessed using standard comparative statistics. Results Our study included 20,961 patients with spinal schwannomas, of whom 4547 (21.7%) underwent surgical resection. Academic centers treated the largest share of patients (11,735, 56.0%), followed by comprehensive community (5015, 23.9%), integrated network (3824, 18.2%), and community programs (387, 1.85%). In the overall cohort, survival did not differ by facility type. Among surgically treated patients, care at an academic facility was associated with improved survival (hazard ratio [HR] = 0.16, P < 0.001). However, following adjustment for institutional surgical volume, facility designation was no longer independently associated with survival (academic facility HR=1.21, P = 0.850), while higher institutional surgical volume remained independently associated with improved survival outcomes (HR = 0.998, P = 0.037). Conclusions Our study finds that facility volume was associated with improved survival for surgical schwannoma patients. This finding suggests potential benefits of centralizing spinal schwannoma care to high-volume centers and underscores the need for further study of referral patterns and operative outcomes.