Spinal Intramedullary Solitary Fibrous Tumor: A Rare and Challenging Diagnosis

Solitary fibrous tumor (SFT) is a benign neoplasm arising in the soft tissue, which can occur anywhere in the body, while it is predominantly found in the visceral pleura. Spinal SFT is quite uncommon, with limited cases having been reported in the literature; especially, SFT occurring in the intramedullary site is extremely rare.

We present a case of a 35-year-old woman presenting with progressive numbness and weakness in the legs and urinary incontinence. Magnetic resonance imaging (MRI) showed an intramedullary lesion with bright enhancement. A diagnosis of spinal hemangioblastoma was suspected, and thus a three-dimensional computed tomographic angiography reconstruction was requested, which also demonstrated an angiomatous lesion. The tumor was completely resected under neurophysiological monitoring. However, histopathological and immunohistochemical examinations revealed an SFT. No adjuvant radiotherapy or chemotherapy was scheduled. The symptoms were relieved completely, and no recurrence or progression was noted during the follow-up.

Though SFT has been considered similar to malignant hemangiopericytoma and the histological classification has always been controversial, the intramedullary location and benign behavior in the present case add to the current understandings of this extremely rare entity.