Malignant schwannoma of the infratemporal fossa: a case report

INTRODUCTION: Malignant schwannomas or neurofibrosarcomas are rare nerve tumors of unknown etiology. These neoplasms are highly aggressive with a marked propensity for local recurrence and metastatic spread. Their management continues to be a challenge for pathologists and surgeons. Maxillofacial locations are very exceptional. We report the case of a patient with unusual malignant schwannoma of the infratemporal fossa discovered at a late evolving stage. CASE PRESENTATION: A 56-year-old woman, of Moroccan nationality, presented to our hospital in 2013 with a large right-sided hemifacial swelling that had evolved over the previous 4 months, with a limitation of mouth opening, nasal obstruction and episodes of epistaxis. A CT scan and MRI showed a large and invasive tumor occupying her right infratemporal fossa and maxillary sinus, with sphenoidal, ethmoidonasal, nasopharyngeal and intraorbital extension. A nasal endoscopic biopsy was performed. Immunohistochemical examination concluded a diagnosis of malignant schwannoma, and a palliative radiotherapy was decided; however, our patient died 10 days later. CONCLUSIONS: Malignant schwannoma of paranasal sinuses and the anterior skull base is a rare tumor that involves a high rate of local invasion. The prognosis is poorer compared to that occurring in the trunk and extremities.