Metastatic Meningioma: Neuroradiologic and Molecular Imaging Perspectives

Abstract

Meningiomas are the most common primary central nervous system tumors, arising from arachnoid cap cells and typically following a benign clinical course. However, a minority of cases-particularly higher-grade meningiomas-exhibit aggressive behavior, including local invasion, recurrence, and, in rare instances, extracranial metastasis. Metastatic meningioma, defined as dissemination beyond the cranial and spinal compartments, remains exceptionally uncommon, with reported incidence ranging from 0.1% to 0.76%. Common metastatic sites include the lungs, bone, liver, and lymph nodes, although virtually any organ may be involved. Proposed mechanisms of spread include hematogenous dissemination via venous sinuses, cerebrospinal fluid seeding in high-grade variants, and possibly lymphatic dissemination. Imaging features that suggest metastatic potential include irregular margins, heterogeneous enhancement, prominent peritumoral edema, and bone destruction. Advanced modalities, such as gallium 68 DOTA-Tyr3-octreotide PET/CT and fluorine 18 fluorodeoxyglucose PET, play an increasing role in detecting and characterizing both known and occult metastatic lesions. Molecular alterations, including TERT promoter mutations, CDKN2A/B deletions, and somatostatin receptor 2 overexpression, are increasingly recognized as important markers for risk stratification and targeted therapy selection. Management requires a multimodal approach, including surgery, radiation therapy, and emerging systemic options such as peptide receptor radionuclide therapy and immune checkpoint inhibitors. Given the rarity and clinical complexity of this entity, radiologists must maintain a high index of suspicion, particularly while evaluating in high-grade or recurrent meningiomas. Keywords: Meninges, Brain/Brain Stem, Neuro-oncology, Molecular Imaging, Metastatic Meningioma, DOTATATE, High-Grade Meningioma, Somatostatin Receptor Imaging, SSTR, Peptide Receptor Radionuclide Therapy © RSNA, 2025.

Keywords: Brain/Brain Stem; DOTATATE; High-Grade Meningioma; Meninges; Metastatic Meningioma; Molecular Imaging; Neuro-oncology; Peptide Receptor Radionuclide Therapy; SSTR; Somatostatin Receptor Imaging.

Figure 1:

Images in a 38-year-old male patient with a right sphenoid wing meningioma (World Health Organization grade 2) who presented with a 4-week history of cough. (A) Axial fused gallium 68 (⁶⁸Ga) DOTA-Tyr3-octreotide (DOTATATE) PET/CT image demonstrates intense tracer uptake in the right sphenoid meningioma. (B) CT lung window image reveals multiple well-defined pulmonary nodules bilaterally, largest in the right lower lobe (arrows). (C) The corresponding axial ⁶⁸Ga-DOTATATE PET/CT image in the chest shows avid tracer uptake in the right lower lobe nodule (dotted arrow), consistent with pulmonary metastases from a DOTATATE-avid meningioma.

Figure 2:

Images in a 42-year-old male patient with a left parietal meningioma (World Health Organization grade 3) extending across the midline. Axial (A) T2-weighted, (B) postcontrast T1-weighted, and (C) T2 fluid-attenuated inversion recovery MR images demonstrate a large, osteolytic meningioma with central necrosis, extensive surrounding vasogenic edema, and features suspicious for parenchymal invasion (arrow). Invasion into the superior sagittal sinus is also noted medially. (D) Axial fused gallium 68 DOTA-Tyr3-octreotide PET/CT image shows intense radiotracer uptake within the lesion. (E) Axial CT lung window image reveals two well-defined right lung nodules, confirmed histopathologically as metastatic meningioma deposits.

Figure 3:

Images in a 53-year-old female patient with a known right sphenoid wing meningioma (World Health Organization grade 3). (A) Axial postcontrast T1-weighted MR image demonstrates an enhancing mass along the right sphenoid wing. (B) Axial noncontrast CT image shows a hypodense soft tissue lesion in the subcutaneous region of the right hypochondrium (arrow). (C) Axial fused gallium 68 DOTA-Tyr3-octreotidee (DOTATATE) PET/CT image reveals intense radiotracer uptake within this subcutaneous lesion, consistent with metastatic disease. (D) Coronal fused PET/CT image demonstrates an additional DOTATATE-avid mass in the left upper lung lobe (dotted arrows). (E) Coronal maximum intensity projection image highlights widespread DOTATATE-avid metastatic lesions throughout the body, including pulmonary, pleural, and subcutaneous sites.

Figure 4:

Images in a 49-year-old male patient with a history of left sphenoid wing meningioma (World Health Organization grade 2 status after debulking 5 years ago) who presented with cough, back pain, and pelvic discomfort for 3 months. (A) Axial postcontrast T1-weighted MR image demonstrates an enhancing residual mass in the left sphenoid bone with surrounding postoperative changes. (B) Chest radiograph reveals multiple bilateral pulmonary nodules, confirmed on (C) coronal maximum intensity projection CT image. (D, F) Axial CT images and (E, G) corresponding fused gallium 68 DOTA-Tyr3-octreotide (DOTATATE) PET/CT images demonstrate DOTATATE-avid lytic lesions (arrow in D and F) at C6 and the left ischial ramus, consistent with osseous metastatic disease.

Figure 5:

Images in a 40-year-old male patient with a known left occipital bone meningioma (World Health Organization grade 3) who presented with chronic back pain. (A) Axial T2-weighted and (B) postcontrast T1-weighted MR images demonstrate a large, heterogeneously enhancing occipital mass with bone destruction and extracranial extension. (C) The corresponding gallium 68 DOTA-Tyr3-octreotide (DOTATATE) PET/CT image shows intense radiotracer uptake within the primary lesion. (D) Axial fused PET/CT image of the thorax reveals focal DOTATATE uptake in a right upper lobe pulmonary nodule (arrow), consistent with metastatic disease. Axial (E) CT and (F) fused PET/CT images of the thoracic spine demonstrate a lytic lesion in the D8 vertebral body (dashed arrow in E) with radiotracer uptake, confirming osseous metastasis.

Figure 6:

Images in a 61-year-old male patient with a known right parietal meningioma (World Health Organization grade 3). Axial (A) noncontrast CT and (B) fused gallium 68 DOTA-Tyr3DO-octreotide (DOTATATE) PET/CT images demonstrate an intensely DOTATATE-avid enhancing mass along the right parietal convexity. Axial (C) CT and (D) corresponding fused PET/CT images reveal a large, osteolytic soft tissue mass with intense radiotracer uptake involving the right iliac bone. (E) Coronal maximum intensity projection image shows radiotracer accumulation in both the primary intracranial lesion and the right iliac metastasis (dotted arrows).

Figure 7:

Images in a 27-year-old female patient with a parafalcine meningioma (World Health Organization grade 1). (A, B) Coronal postcontrast T1-weighted MR images show a homogeneously enhancing mass in the left parafalcine region crossing the midline and invading the superior sagittal sinus. A second discrete enhancing lesion is noted along the left parietal convexity (arrow in B). (C) Sagittal and (E) axial CT bone window images reveal a lytic lesion with sclerotic margins involving the D9 vertebral body. Corresponding (D) sagittal and (F) axial fused gallium 68 DOTA-Tyr3-octreotide PET/CT images demonstrate intense radiotracer uptake in the D9 lesion. (G) Final axial CT image shows a CT-guided biopsy needle within the vertebral lesion, which was histopathologically confirmed as metastatic meningioma.

Figure 8:

Images in a 30-year-old male patient with a history of left frontal meningioma (World Health Organization grade 3) resected 7 years earlier, presenting with new-onset lower back pain. (A) Sagittal and (B) coronal postgadolinium T1-weighted MR images reveal a recurrent enhancing mass in the left frontal region with both intra- and extracranial components, invading the superior sagittal sinus. Sagittal (C) short tau inversion recovery and (D) T2-weighted spinal images show a focal lesion with altered signal intensity involving the D11 vertebral body (arrow). Subsequent biopsy confirmed the lesion as metastatic meningioma.

Figure 9:

Images in a 37-year-old female patient with a history of resected right frontoparietal World Health Organization grade 2 meningioma, presenting 7 years later with neck pain. (A) Sagittal reformatted contrast-enhanced CT image shows postoperative calvarial changes (solid arrow). (B) Axial CT image in the soft tissue window image reveals an osteolytic soft tissue lesion (dotted arrow) involving the C5 vertebral body. (C) Sagittal T2-weighted MR image demonstrates altered signal intensity at the same vertebral level (dotted arrow). Biopsy confirmed the lesion as metastatic meningioma.

Figure 10:

Images in a 56-year-old female patient with a previously resected right parietal meningioma (World Health Organization grade 3) who presented 8 years later with abdominal pain. (A) Baseline axial postcontrast T1-weighted MR image shows a well-defined, intensely enhancing mass along the right parietal convexity. Subsequent (B) axial and (C) coronal T2-weighted MR images demonstrate a large lobulated mass nearly replacing the right hepatic lobe. (D) Diffusion-weighted image reveals restricted diffusion within the lesion, and (E) postgadolinium T1-weighted image shows heterogeneous enhancement. (F) Fused axial gallium 68 DOTA-Tyr3-octreotide PET/CT image demonstrates intense radiotracer uptake within the hepatic mass. (G, H) Gross pathology images show a well-circumscribed, tan-colored hepatic mass with a lobulated cut surface, confirming metastatic meningioma.

Figure 11:

Images in a 45-year-old female patient with a history of resected meningioma (World Health Organization grade 1) who presented for unrelated evaluation. (A) Coronal reformatted contrast-enhanced CT image in soft tissue window demonstrates a well-defined lesion (arrow) in the left hepatic lobe. (B) Coronal and (C) axial T2-weighted MR images along with (D) postgadolinium T1-weighted image show a hyperintense lesion with mild enhancement (arrow). Histopathology findings confirmed the hepatic lesion as a metastatic meningioma.