Meningioomat

Meningioomat, or meningiomas, are tumors that develop from the meninges, the membranes surrounding the brain and spinal cord. Most originate from arachnoid cap cells and are typically extra-axial and slow-growing. They account for about 30% of intracranial tumors in adults and are more common in women. The vast majority are benign (World Health Organization grade I), though a minority are atypical (grade II) or malignant (grade III).

Symptoms depend on location and may include headaches, seizures, focal weakness or sensory changes, cognitive or personality changes, and vision problems when near the optic pathways. Many meningiomas are found incidentally on imaging performed for unrelated reasons.

Diagnosis is usually by magnetic resonance imaging with contrast, which characteristically shows a dural-based, well-circumscribed mass with strong enhancement and often a dural tail. Computed tomography can reveal calcifications or bone remodeling. Definitive grading requires histological examination after biopsy or surgical resection.

Treatment depends on size, symptoms, growth rate, and patient factors. Small, asymptomatic tumors may be observed with serial imaging. Symptomatic or enlarging tumors are commonly treated with surgical resection, aiming for gross total removal when feasible. Radiotherapy, including stereotactic radiosurgery or conventional fractionated radiotherapy, is used for residual, recurrent, unresectable, or higher-grade tumors.

Prognosis is generally favorable for WHO grade I meningiomas after successful resection, but recurrence is possible, particularly after subtotal resection or for higher-grade tumors. Spinal meningiomas have similar biology and are usually managed with surgery, often with good outcomes; they may present with radicular pain or myelopathy.

Genetic associations include mutations in the NF2 gene on chromosome 22 and a link to neurofibromatosis type 2; hormonal factors may play a role, contributing to higher incidence in women.