From the Guidelines
Meningiomas can indeed metastasize, although this occurrence is extremely rare, with evidence suggesting the possibility of detecting extracranial metastases 1. When considering the potential for metastasis, it's crucial to understand that meningiomas are typically benign tumors originating from the meninges, the protective membranes surrounding the brain and spinal cord. However, a small percentage, approximately 1-2% of all meningiomas, can exhibit metastatic behavior, particularly those classified as higher-grade, such as WHO grade II (atypical) and grade III (anaplastic/malignant) tumors 1.
Key Points to Consider:
- The rarity of metastasis in meningiomas does not negate the importance of thorough diagnostic assessment, including the use of radiolabeled somatostatin receptor ligands for theranostics, as outlined in recent guidelines 1.
- Detection of multifocal disease or extracranial metastases is a critical aspect of managing meningiomas, highlighting the need for comprehensive imaging and follow-up 1.
- While the exact mechanism of metastasis in meningiomas involves complex biological processes, the clinical implication is that patients, especially those with higher-grade tumors, should be closely monitored for any signs of metastatic spread 1.
- Risk factors for metastasis, including prior surgical interventions, specific tumor characteristics, and the presence of local recurrence, should be carefully evaluated in the clinical assessment of patients with meningiomas 1. Given the potential, albeit rare, for meningiomas to metastasize, clinical management should prioritize thorough diagnostic evaluation and regular follow-up to ensure early detection and appropriate intervention should metastasis occur 1.
From the Research
Meningioma Metastasis
- Meningiomas are generally considered to be slow-growing and benign tumors, but they can be classified into three grades, with Grade I being the most common and benign, and Grade III being the most aggressive and malignant 2.
- While meningiomas are typically not known to metastasize, there have been rare cases reported in the literature, with a frequency of approximately 0.1% of cases 3.
- Metastatic meningiomas (MMs) are often treated with a multimodal approach, including surgery, radiotherapy, chemotherapy, and radiosurgery, which can provide long-term local control and extension of free survival 3.
- The possibility of metastasis should be considered when diagnosing and treating meningiomas, especially in cases where the tumor is located in critical regions or has a high grade of malignancy 2, 3.
- Advances in genomics and molecular characteristics of meningiomas have uncovered potential uses for more accurate grading and prediction of prognosis and recurrence, which may also help identify cases with a higher risk of metastasis 4.