Clinical Features, Management and Prognostic Factors of Intracranial Solitary Fibrous Tumor

Abstract Purpose Due to low incidence and the constantly changing diagnostic and classification criteria, the clinical features, management and prognostic factors of intracranial solitary fibrous tumor (ISFT) remain unclear and were thus analyzed in this study. Methods A total of 38 patients who were diagnosed as ISFT in our institution were enrolled in this study. Patient data including age, gender, clinical presentation, histopathological features, immunohistochemistry staining, tumor location, tumor size, treatment methods, and prognosis were extracted and retrospectively analyzed. Results The median age at diagnosis was 45.5 years (range 28-66 years) and the male to female ratio was 1:1.53 in our series. The 3-, 5-, and 10-year progression-free survival rate was 82.2%, 62.8%, and 21.4%, respectively; and the 3-, 5-, and 10-year overall survival rate was 97.1%, 86.9% and 64.2%, respectively. Patients with high WHO grade (grade III) ISFTs had impaired PFS (p<0.05) and OS (p<0.01). Subtotal resection (STR) was associated with shorter PFS and OS (p<0.001, respectively). Postoperative radiotherapy (PORT) significantly improved PFS but not OS in patients with WHO grade III ISFTs (P=0.025). The PFS of patients with STR+PORT was improved compared with those who received STR alone, although not significant. Moreover, CD34-negative immunostaining and high Ki-67 index (>10%) were associated with impaired PFS in ISFTs.Conclusion Our study provides evidence that high tumor grade, subtotal tumor resection, CD34 negative immunostaining and high Ki-67 index (>10%) were independent predictors for poor prognosis of ISFTs. PORT should be recommended for patients with high grade ISFTs or STR.