Management Options for Meningioma
The management of meningiomas should follow a stepwise approach based on tumor grade, location, and symptomatology, with surgery being the primary treatment for symptomatic or growing meningiomas, followed by radiation therapy for incompletely resected or higher-grade tumors. 1
Diagnostic Evaluation
- Imaging: High-resolution CT scan with thin collimation and high spatial reconstruction algorithm is essential for diagnosis 2
- Molecular Testing:
- Cases with borderline morphological grading criteria should undergo molecular testing 2
- Testing for chromosome 1p status is recommended in specific scenarios to determine accurate grading 2
- Brain-invasive but otherwise morphologically benign meningiomas should not be graded before molecular data are obtained 2
Management Algorithm
1. Observation/Surveillance
- Appropriate for:
- Asymptomatic, small, incidentally discovered meningiomas
- Low-grade (WHO grade 1) meningiomas without growth
- Imaging follow-up at 6 months initially, then yearly 2
2. Surgical Management
- Primary treatment for:
- Symptomatic meningiomas
- Growing meningiomas
- Meningiomas causing mass effect
- Meningiomas with surrounding edema
- Surgical Goals:
- Maximal safe resection
- Preservation of neurological function
- Obtaining tissue for histopathological diagnosis
3. Radiation Therapy
WHO Grade 1 and 2 Meningiomas:
WHO Grade 3 Meningiomas:
- Treated as malignant tumors
- Tumor bed and gross tumor + margin (2-3 cm) receiving 54-60 Gy in 1.8-2.0 Gy fractions 2
4. Peptide Receptor Radionuclide Therapy (PRRT)
- Somatostatin Receptor (SSTR)-directed PRRT:
- Investigational treatment for progressive meningiomas
- Consider only if other local therapy options (surgery, radiotherapy) are not applicable 2
- Requires positive expression of SSTR type 2 receptors on SSTR-directed PET imaging 2
- Contraindications include:
- Compromised renal function (GFR <40 ml/min/1.73 m²)
- Compromised bone marrow
- Hepatic failure 2
Treatment Recommendations by Tumor Grade
WHO Grade 1 Meningiomas
- Asymptomatic: Observation with serial imaging
- Symptomatic or growing: Surgery with goal of complete resection
- Incompletely resected: Consider observation or radiation therapy based on location and residual tumor volume
WHO Grade 2 (Atypical) Meningiomas
- Complete resection: Consider adjuvant radiation therapy
- Incomplete resection: Adjuvant radiation therapy recommended
- Molecular features: Meningiomas with chromosome 1p deletion and concurrent 22q deletion/NF2 oncogenic variant should be assigned to "CNS WHO grade 2" 2
WHO Grade 3 (Anaplastic/Malignant) Meningiomas
- Surgery followed by adjuvant radiation therapy regardless of extent of resection 2
- Higher radiation doses: 54-60 Gy in 1.8-2.0 Gy fractions 2
Special Considerations
Meningiomas in Patients with LAM
- Brain MRI should be performed in the presence of symptoms compatible with meningioma 2
- Brain MRI screening for meningioma should be performed in females with LAM receiving progestative drugs 2
Meningiomas in NF2 Patients
- 50-60% of NF2 patients present with an average of three meningiomas 2
- Management includes surveillance and surgery depending on tumor growth history 2
- Radiosurgery may be helpful for rare symptomatic growing tumors, particularly in the cavernous sinus where surgery is not recommended 2
Monitoring and Follow-up
- Clinical and radiological (MRI) follow-up at 6 months initially, then yearly for stable disease 2
- More frequent imaging for growing tumors or higher-grade lesions
Pitfalls and Caveats
- Radiation therapy carries risk of secondary malignancies, especially in NF2 patients 2
- Molecular testing is critical for accurate grading and treatment planning 2
- Current recommendations do not apply to pediatric, radiation-associated, or NF2-related meningiomas as these are poorly represented in available studies 2
- The extent of resection is a well-established prognostic factor that significantly influences clinical management 2