Recurrence and increased proliferation rate of a solitary fibrous tumor in the central nervous system--case report and review of the literature.

Meningeal solitary fibrous tumors (SFTs) were at first estimated as rare benign tumors which can be cured by total resection. To date, only 37 patients with intracranial SFTs have been reported. Therefore, the natural history of this tumor entity needs more enlightenment. The authors report a case of a 77-year-old female in whom a SFT with infiltration of the transversal sinus was subtotally resected. After a short time, interval tumor recurrence was seen, 2 years and 6 months later second surgery was performed. Immunohistologically, in both specimens typical features for SFT with positivity for CD34, vimentin and BCL-2 and negative for epithelial membrane antigen was seen. No signs for malignancy occurred in the second resection. Notably the MIB-1 index increased from 1 to 5%. In conclusion, consequent long-time follow-up for SFTs are necessary, especially after incomplete tumor resection.