Introduction: Solitary fibrous tumors are rare neoplasms of mesenchymal origin, first identified as arising from the pleura. They have subsequently been described across many extrapleural sites, with 5-27% arising in the head and neck region. Amongst the rarest subsites is the sinonasal tract, with fewer than 100 cases reported in the English literature. While slow growing, these tumors have the potential for malignant spread, local invasion of critical structures, and life-threatening hemorrhage; thus, early identification and management with surgical resection is critical. We report a rare solitary fibrous tumor of the nasal cavity successfully removed with endoscopic surgical resection after embolization.
Case Presentation: An 84-year-old Caucasian male presented to an outside emergency department with presyncope, hypotension, and anemia in the setting of 6 months of intermittent right-sided epistaxis. During intubation for elective esophagoscopy in the workup of anemia, the patient developed large-volume right-sided epistaxis requiring placement of posterior balloon nasal packing and transfer to our institution. A CT angiogram of the head and neck was obtained which demonstrated a large, ill-defined mass of the left nasal cavity with focal areas of hyperdensity and extensive nasopharyngeal extension without erosive change of the skull base. Gadolinium-enhanced MRI of the face demonstrated a large, expansile, T1 isointense, T2 hyperintense mass with heterogenous enhancement and no intracranial extension or involvement of the parapharyngeal and pharyngeal spaces. The patient underwent angiography and embolization of significant vascular supply from the left internal maxillary artery; packing was kept in place given contributions noted from internal carotid artery branches which were deemed poor candidates for embolization. He was subsequently taken to the operating room for packing removal and biopsy during which aggressive bleeding was controlled. Biopsy revealed a patternless hypercellular neoplasm composed of sheets of uniform bland spindle cells separated by vascular spaces, with immunohistochemical staining positive for STAT6, CD99, and rare CD34 – findings consistent with a diagnosis of solitary fibrous tumor.
A subsequent PET-CT was negative for evidence of metastasis. Multidisciplinary discussions with oncology and neurosurgery teams along with the patient and family agreed with total surgical resection up to the boundaries of the nasal cavity and sinuses. The patient was discharged and returned several weeks later for repeat IR embolization of the left internal maxillary artery followed by same-day endoscopic resection of the tumor. Intraoperative findings revealed tumor attachment at the middle turbinate junction with the cribriform plate near the anterior ethmoid artery. The skull base mucosa at the attachment site was removed, however the bone was left intact as decided in preoperative discussions. The patient tolerated the procedure well and was discharged home the following day. Final pathology confirmed the diagnosis of solitary fibrous tumor of intermediate risk (Demicco score=4/6), conferring a 10% 10-year metastatic risk.
Conclusions: This case illustrates presentation, accurate diagnostic workup, and appropriate management of a rare mesenchymal sinonasal tumor. While often slow growing, expeditious identification and treatment of these tumors is paramount given risk for life-threatening hemorrhage, local invasion, and distant metastasis.