What are the treatment options for a patient diagnosed with a meningioma?

Treatment Options for Meningioma

Surgical resection is the primary treatment for most meningiomas, followed by radiotherapy for incompletely resected or recurrent tumors, with systemic therapies reserved for cases where surgery and radiation have failed or are not feasible. 1, 2

Initial Treatment Approach

Surgical Resection

• First-line treatment for most meningiomas, particularly symptomatic ones
• Goals:
  • Complete removal of tumor (gross total resection)
  • Relief of neurological symptoms
  • Tissue acquisition for histopathological diagnosis and grading
• Complete resection is often curative, especially for WHO grade 1 tumors 1, 3
• Surgical approach is influenced by:
  • Tumor location and accessibility
  • Proximity to critical neurovascular structures
  • Patient's overall health status

Stereotactic Radiosurgery (SRS)

• Recommended as an effective evidence-based treatment option (recommendation level II) for grade 1 meningiomas 1
• Typical prescription dose: 12-15 Gy delivered in a single fraction
• 10-year local control rates: 71-100%
• Particularly useful for:
  • Surgically inaccessible tumors
  • High-risk surgical patients
  • Elderly patients
  • Residual or recurrent disease after surgery

Treatment Based on WHO Grade

WHO Grade 1 (Benign) Meningiomas (75-80% of cases)

1. Complete surgical resection when feasible
2. Post-operative surveillance with MRI without and with IV contrast every 6-12 months 1
3. For incompletely resected tumors:
   • Observation with serial imaging
   • Stereotactic radiosurgery/radiotherapy

WHO Grade 2 (Atypical) Meningiomas (15-20% of cases)

1. Maximal safe surgical resection
2. Adjuvant radiotherapy often recommended for:
   • Subtotal resection
   • Recurrent disease
3. More frequent imaging follow-up than grade 1 tumors 1, 4

WHO Grade 3 (Anaplastic/Malignant) Meningiomas (1-5% of cases)

1. Aggressive surgical resection when possible
2. Adjuvant radiotherapy strongly recommended
3. Poor prognosis with median survival <2 years despite treatment 1, 5
4. Consider clinical trials or experimental therapies

Treatment for Recurrent or Progressive Disease

Local Treatment Options

1. Repeat surgical resection if feasible
2. Salvage radiotherapy if not previously administered 1
3. Re-irradiation in selected cases

Systemic Therapy Options

• Limited efficacy data for all systemic therapies
• Consider when surgery and radiotherapy options are exhausted 2
• Potential options include:
  • Hydroxyurea (modest success in recurrent cases) 2
  • Targeted therapies based on molecular profiling (investigational)
  • Hormonal therapy (limited evidence)

Molecular Considerations in Treatment Planning

Recent advances in molecular profiling have identified potential therapeutic targets in meningiomas 1:

• NF2 alterations and mTOR pathway activation have reached ESCAT II ("investigational") classification
• No molecular targets have reached ESCAT I ("ready for clinical use") classification
• Molecular testing is not recommended at initial diagnosis but may be relevant at recurrence when considering targeted therapies 1

Special Considerations

Observation Strategy

• Appropriate for small, asymptomatic meningiomas
• Regular imaging surveillance to monitor for growth
• Particularly suitable for elderly patients or those with significant comorbidities 3

Radiation Therapy Approaches

• Conventional external-beam radiation therapy
• Stereotactic radiosurgery (SRS) - single fraction
• Hypofractionated stereotactic radiotherapy (HSRT) - ≤5 fractions
• Fully fractionated stereotactic radiotherapy (SRT) - multiple fractions over 5-6 weeks 1

Emerging Treatment: Peptide Receptor Radionuclide Therapy (PRRT)

• Experimental therapy using radiolabeled somatostatin receptor ligands
• Decision to recommend PRRT should be made within a multidisciplinary neuro-oncology board
• Patients should be enrolled in clinical trials whenever possible 1

Imaging for Treatment Planning and Follow-up

• MRI without and with IV contrast is the standard imaging modality 1
• Typical MRI features of meningiomas:
  • Homogeneous dural-based enhancement
  • Presence of a dural tail
  • CSF cleft between tumor and brain
• DOTATATE PET/CT or PET/MRI may provide more accurate delineation of resection extent, particularly for WHO grade 2 and 3 tumors 1

By carefully considering tumor grade, location, patient factors, and molecular characteristics, the optimal treatment approach can be determined to maximize tumor control while preserving neurological function and quality of life.