2026 Poster Presentations
P161: MAXILLARY SINUS INFRAORBITAL NEUROFIBROMA: A CASE REPORT AND REVIEW OF THE LITERATURE
Eric J Paget, PAC; Molly Murray, MD; Christopher Jabbour, MD; Maria Peris Celda, MD, PhD; Jacob G Eide, MD; Mayo Clinic
Introduction: Neurofibromas (NF) are rare benign peripheral nerve sheath tumors most commonly found in the skin and subcutaneous tissues. Given the limited number of reported maxillary neurofibroma cases, we present a review of the relevant literature and report a unique case to further expand the skull base annals.
Methods: Institutional review board exemption was obtained for retrospective review. Relevant literature review was performed through PubMed search.
Results: A 19-year-old male with a remote past medical history of embryonal rhabdomyosarcoma of the skull base centered around the petrous apex presented to clinic for evaluation. He had undergone chemotherapy followed by radiation in childhood. The NF was incidentally noted in the right maxillary sinus on oncologic magnetic resonance imaging (MRI) surveillance. The lesion was noted to increase in size on a subsequent MRI, which prompted a biopsy consistent with neurofibroma. MRI revealed a T2 hyperintense enhancing lesion along the right inferior orbital fissure, measuring approximately 3.2 x 1.7 x 1.4 cm (Figure 1). Options for treatment of the NF were discussed including observation, gamma knife radiosurgery, or endoscopic resection. Resection was elected, so we proceeded with an endoscopic modified Denker’s approach, revealing the mass in the lateral maxillary sinus wall and inferior orbital fissure (Figure 2). Frozen section pathology demonstrated neurofibroma. Postoperatively, the patient had facial numbness as expected. His postoperative course was otherwise uncomplicated without diplopia or epistaxis. There has been no evidence of recurrence on endoscopic surveillance or MRI at 6 months post-operatively.
Review of the literature demonstrates that approximately 25-44% of neurofibromas arise in the head and neck, with less than 4% found in the paranasal sinuses. The most common location for a sinonasal NF is the maxillary sinus, with potential symptoms of diplopia, facial pain/pressure, facial numbness, epistaxis or nasal obstruction depending on the size of the mass. Though rare, radiation exposure is a known risk factor for the development of solitary neurofibroma in patients without a history of neurofibromatosis type 1 (NF1).
Conclusion: NF are a rare sequelae of skull base radiation and may require surgical excision. This lesion may be confused with tumor recurrence or development of a radiation-induced malignancy.
Figure 1. Imaging at the time of presentation. MR imaging demonstrates a T2 hyperintense, enhancing lesion along the right inferior orbital fissure. (A/B)
Figure 2. Endoscopic modified Denker’s approach, revealing adequate visualization of the lateral right maxillary wall and neurofibroma (C). Dissection was carefully performed to mobilize the mass away from the periorbita keeping the orbital fat and inferior rectus muscle intact. The infraorbital nerve was sacrificed as expected to remove the mass (D).
