What Is It? A Rare Presentation of a Meningioma.

Primary extracranial meningiomas are rare manifestations of a central nervous system tumor. This article presents a case study of a soft-tissue primary extracranial tumor in the temporal region that was initially diagnosed as melanoma at an outside institution and whose definitive diagnosis proved difficult prior to successful excision. Temporal muscle biopsy, ultrasound-guided biopsy, and computed tomography were conducted at an outside institution prior to the patient's presentation to our care. Upon presenting to our institution a positron emission tomographic scan was then conducted prior to excision. After excision, the mass was sent to pathology and further immunohistochemistry was conducted. To ensure the mass was completely excised, magnetic resonance imaging was performed after its removal. A 3 × 3-cm mass was excised in its entirety from the patient's temporal region and sent to pathology for immunohistochemistry and mutation testing. It proved to have the most common mutation for a primary extracranial meningioma, a neurofibromatosis type 2 frameshift. The presentation of a primary extracranial meningioma in the temporal region is a rare finding. Because of its slow-growing nature and generally asymptomatic presentation, it can be misdiagnosed. Utilization of radiological imaging is essential both pre- and postoperatively in order for its identification and complete excision.