Stereotactic radiosurgery as adjuvant or salvage treatment for sporadic hemangioblastomas: a multi-center international study

Abstract

Introduction: Hemangioblastomas are rare benign CNS tumors, occurring sporadically or with von Hippel-Lindau disease. While surgical resection is the primary treatment, GKRS serves as an adjuvant or salvage option when resection is not feasible. This study evaluates long-term outcomes of GKRS in patients with sporadic hemangioblastomas. Methods: We retrospectively analyzed 82 patients with sporadic hemangioblastomas treated with GKRS across 17 International Radiosurgery Research Foundation centers (1993-2022). Univariate and multivariate analysis was conducted to identify variables influencing local control and tumor regression. Results: Among 82 patients (52.4 % male, median age 51.5 years [IQR: 40.3-63.0]), most tumors were cerebellar (70.7 %), solid (63.4 %), with a median volume of 1.8 cc [IQR: 0.8-6.1]. The median margin dose was 16.0 Gy [IQR: 14.0-18.0]. With a median follow-up of 51.5 months [IQR: 21.0-92.0], local control was achieved in 69.5 % of cases (40.2 % regression, 29.3 % stability). Local control rates were 95 % (90 %, 100 %) at 6 months but declined to 75 % (65 %, 87 %) at 60 months. Radiation necrosis occurred in 6.1 % of patients (5/82), and no tumor-related deaths were reported among the 11.1 % overall mortality. Brainstem location was significantly linked to lower odds of tumor regression in the multivariate analysis (OR: 0.29, 95 % CI: 0.09-0.98, p = 0.045). Conclusion: GKRS demonstrated efficacy and safety in treating sporadic hemangioblastomas, achieving reasonable long-term local control rates with minimal complications. Our findings support its role as a viable treatment option, particularly for surgically challenging cases.