Prognostic Factors of Survival for Grade 3 Solitary Fibrous Tumor/Hemangiopericytoma: A Population-Based Retrospective Surveillance, Epidemiology, and End Results Database Analysis

<b><i>Introduction:</i></b> Grade 3 solitary fibrous tumor, previously known as anaplastic hemangiopericytoma, is a rare and highly malignant intracranial tumor with a limited understanding of its natural history and treatment outcomes. <b><i>Methods:</i></b> We conducted a retrospective analysis using the Surveillance, Epidemiology, and End Results (SEER) database spanning 2000–2019 to evaluate the clinical characteristics and treatment modalities that influence overall survival in this tumor entity. A cohort of 249 patients with intracranial grade 3 solitary fibrous tumors was identified. Univariate and multivariable Cox proportional hazard models were employed to determine significant prognostic factors for overall survival. Kaplan-Meier models were used to visualize survival curves, and a nomogram was constructed to predict survival probabilities at 6- and 12-month following diagnosis. <b><i>Results:</i></b> Our findings indicated that patient age (&lt;65 years), localized or regional disease burden, surgical resection, and radiation therapy were significant predictors of better overall survival. Combination therapies showed improved survival, with surgery and radiation therapy having the most significant impact. However, chemotherapy alone or in combination did not demonstrate a significant survival benefit, likely due to the limited sample size. The nomogram provided personalized prognostic predictions based on significant clinical factors. <b><i>Conclusions:</i></b> These data emphasize the importance of surgical resection and radiation therapy in the management of grade 3 solitary fibrous tumors, supporting the use of combination therapies to improve overall survival in this rare and aggressive intracranial neoplasm.