Benign metastasizing meningiomas are a rare occurrence, encountered as a complication of a tiny fraction of all meningiomas diagnosed. It refers to spread of the tumor via metastases to distant sites, analogous to benign metastasizing leiomyoma from uterine fibroids.
The incidence of benign metastasizing meningiomas is less than 0.1% of meningiomas 2.
Presentation is very nonspecific with metastases reported widely throughout the body 1:
- pulmonary (60%)
- abdomen (34%) (mostly liver)
- cervical lymph nodes (18%)
- long bones, pelvis , skull (11%)
- pleura (9%)
- vertebra (7%)
- central nervous system (7%)
- mediastinum (5%)