What are the latest treatment guidelines for meningioma?

Latest Guidelines for Meningioma Treatment

Somatostatin receptor (SSTR) PET imaging is now recommended in the diagnostic workup for meningiomas when tumor extension is unclear or for differentiating recurrence from post-treatment changes, according to the 2024 joint EANM/EANO/RANO/SNMMI practice guidelines. 1

Diagnostic Imaging

• MRI with contrast remains the standard initial diagnostic imaging modality for meningiomas, providing detailed characterization of the lesion and surrounding structures 2
• SSTR PET imaging offers superior detection sensitivity compared to contrast-enhanced MRI alone and should be obtained if tumor extension or diagnosis of recurrence is unclear (evidence class 3, recommendation level C) 1
• SSTR PET is particularly valuable for:
  • Differential diagnosis between meningioma and non-meningioma tissue 1
  • Assessment of tumoral extent for surgical and radiotherapy planning 1
  • Detection of multifocal disease or extracranial metastases 1
  • Differentiation between tumor recurrence and treatment-induced changes 1

Treatment Algorithm

Surgical Management

• Complete surgical resection with removal of dural attachment is the optimal treatment when feasible 2, 3
• Modern surgical techniques including image-guided surgery improve precision and may reduce surgical morbidity 2
• For asymptomatic small meningiomas (<30 mm), observation is appropriate, with surgery considered if the tumor is accessible and potential neurological consequences exist 2
• For symptomatic meningiomas, surgery is recommended if accessible 2

Radiation Therapy

• External beam radiation therapy (EBRT) is indicated for:
  • WHO grade 3 (malignant) meningiomas after surgery 2
  • Subtotally resected WHO grade 2 (atypical) meningiomas 2, 4
  • Recurrent meningiomas not previously irradiated 3
• Stereotactic radiotherapy (SRS) may be considered in lieu of surgery for:
  • High-risk patients 3
  • Meningiomas in eloquent or surgically inaccessible locations 3
  • Elderly patients 3

Advanced Treatment Options: Peptide Receptor Radionuclide Therapy (PRRT)

• PRRT using radiolabeled somatostatin receptor ligands shows promising results for treatment-refractory meningiomas 1
• PRRT remains investigational and should be considered only when other local therapy options (surgery, radiotherapy) are not applicable 1
• Patient eligibility criteria for PRRT include:
  • Positive somatostatin receptor expression on SSTR PET imaging within the last 2 months 1
  • Karnofsky performance status above 60% or ECOG 0-2 1
  • No contraindications to PRRT 1

Post-Treatment Surveillance

• For WHO grade 1 meningiomas, MRI without and with contrast every 6-12 months is recommended 2
• SSTR PET is useful in distinguishing tumor recurrence from post-treatment changes 1, 2
• Response assessment to therapeutic interventions is currently performed using MRI-based criteria such as modified Macdonald criteria or RANO criteria 1

Special Considerations

• Skull base meningiomas may require specialized surgical expertise and a multidisciplinary approach 5
• Atypical (WHO grade 2) meningiomas have borderline histologic and clinical features between benign and malignant meningiomas, requiring more aggressive management 4
• When meningioma is unresectable or all other treatments have failed, hormonal therapy or chemotherapy may be considered, though with limited efficacy 3, 6

Important Pitfalls to Avoid

• Not all enhancing dural-based lesions are meningiomas; other entities such as brain metastases, gliomas, and primary CNS lymphoma can mimic meningiomas 5
• Active inflammatory lesions may present increased uptake on SSTR PET (e.g., granulomatous inflammation and neurosarcoidosis) 1
• Uptake on SSTR PET may be decreased or absent in rare cases of meningioma 1