Intracranial solitary fibrous tumor with myxoid features: An unusual presentation

To the Editor: Solitary fibrous tumor (SFT), formerly known as hemangiopericytoma, is a mesenchymal neoplasm that may occur in the CNS, among numerous other locations. Classically, SFT shows spindled to ovoid cells in a collagenous background with branching “staghorn” blood vessels. The tumor is driven by a fusion of the NAB2 and STAT6 genes, the expression of which can be tested by immunohistochemistry (IHC).1 Myxoid histopathology is unusual in SFT and is exceedingly rare in SFT of the CNS. Here, we report a diagnostically challenging brain tumor case that proved to be an intracranial SFT with prominent myxoid features. A previously healthy 74-year-old man presented with a sudden onset of blurred vision. MRI revealed a contrast-enhancing, hemorrhagic, lobulated dural-based mass arising from the planum sphenoidale (Figure 1A); there was prominent edema on fluid-attenuated inversion recovery. The mass measured 5.2 × 3.7 × 3.5 cm. Interestingly, retrospective review of imaging from 9 years prior to presentation showed a