Rare Anatomical Presentation and Clinical Course in Multiple Meningiomas: Insights from a Single-Surgeon Case Series

Abstract Multiple meningiomas (MMs) represent an uncommon condition, frequently associated with neurofibromatosis type 2, prior radiotherapy (RT), or sporadic mutations. Although most lesions arise along the convexity or skull base, other presentations have occasionally been reported. To analyze the incidence, topography, and anatomical particularities of six MM cases that stand out among 25 identified in a cohort of 467 surgically treated patients. A retrospective review of medical records and imaging studies was conducted for patients who underwent total resection of MMs with histopathological confirmation. Cases with two or more noncontiguous tumors were included. A literature review was performed to compare the findings with previously published reports. MMs were observed in 25 patients (5.4%). Of these, six were analyzed due to their unusual presentation, including four with tumors in rare locations: MMs in the posterior fossa with distinct histology; tumors in the pterygoid fossa and frontal convexity; meningiomas along the tentorial edge, contralateral cerebellopontine angle, and sphenoid wing; and two en plaque meningiomas located in the sphenoidal and parasagittal regions, associated with additional lesions involving the clivus and tentorial margin. Anaplastic meningiomas are presented in two cases, both developed after RT, chemotherapy, and hormonal therapy for breast cancer in patients who had previously undergone surgery for meningothelial meningiomas. No treatment-related or tumor-related deaths were observed. Most cases demonstrated Grade 1 meningothelial histology. Among the six cases, 83% were female. MMs may present with a wide variety of features, requiring careful clinical and radiological assessment to guide appropriate management and minimize complications.