Meningiomas are based on the meninges (Spinngewebshaut, arachnoid). This covers the brain under the dura mater. Most of these tumors are benign and grow slowly. Some of them may calcify. One often observes a concomitant broadening of the overlying bone. The tumors may show nodular and space-occupying or a flat growth form. 85% of all meningiomas are benign, 8-10% atypical and 2-5% anaplastic. The onset usually occurs between the ages of 50 and 60. Women are slightly more likely to be affected by this brain cancer.

Meningiomas can grow wherever arachnoid cells (see above) are present. These can be found, for example, between the brain and the skull, in the ventricles or along the spinal cord canal. Most meningiomas (60-70%) are located on the falx (crescent brain, separating meninges between the two halves of the brain), convexity (outer brain surface) and sphenoid wing. Meningiomas are rarely found in the spinal canal.

The clinical symptoms depend on the localization and related compressions. For example, a convexity meningioma, which is in the range of the motion centre for arms and legs, can trigger a paresis. Irritation of brain meningiomas may also cause seizures. Due to their slow growth and adaptability of the brain,meningiomas can achieve a certain size until they are striki

The first diagnosis is made by computed tomography (CT) and magnetic resonance imaging (MRI). If necessary, a MR angiography, a functional MRI and MR spectroscopy, or positron emission tomographs (PET) are complemented measures. It is usually a sharply defined mass with variable degrees of perifocal edema which has an intense homogeneous uptake of contrast agent. Meningiomas which grow very slowly prone to calcification. 9% of patients have multiple meningiomas. 27% of meningiomas show genetic changes (monosomy 22). An increased incidence can be seen in neurofibromatosis type II and a prior radiotherapy. During pregnancy, its growth can accelerate.

Not every meningioma requires immediate treatment. In some cases, it only requires a follow-up study. In another case, a CyberKnife treatment is carried out; an urgent surgical treatment is necessary in a case of intracranial pressure. If a meningioma has to be treated can be decided by the neurosurgeon, depending on the patient’s symptoms and results of the MRI / CT scans.

Operation
In the microsurgical operation a removal of the brain tumor as complete as possible is treatment target. Repeated removal of tumors with incomplete resection or regrowth is possible. In many cases of remained meningiomas a computer or magnetic resonance imaging study course is exclusively aimed, as may this can result in years of growth arrest. At very vascularized tumors, a preoperative embolization is possible. Anaplastic meningiomas, if necessary, could be treated with an additional radiotherapy.

Radiosurgery (CyberKnife, ZAP-X)
The radiosurgical treatment with CyberKnife and ZAP-X can be used as primary treatment for small, difficult to remove tumors (eg sinus cavernous meningiomas) when medical reasons decline an operation or radiosurgery is in patients preference. In most cases radiosurgery achieves a high tumor control. In the ERCM over 3000 patients were treated with cerebral and spinal meningiomas successfully. In some cases you may have a combination of surgery and radiosurgery. This is the case when tumors are located so critical that no complete removal is possible. These treatment concepts are discussed in detail with the respective neurosurgical colleagues in advance of treatment and are planned together. Tumors enchasing the optical system will be treated in five sessions.

Chemotherapy
Chemotherapeutic approaches mostly show no clear benefit. Thez may be applied in very selected cases. Experimental therapies with hormonal therapies or hydroxyurea have not yet found their way into clinical routine. So far, there is no standard approach for chemotherapy. There are individual clinical and experimental studies to chemotherapeutic treatments of meningiomas.

Concomitant drug therapy
In case of a peritumoral edema (see above) in the adjacent brain tissue and related neurological problems, it may be necessary to treat with cortisone to reduce the edema. In most cases, the patient is receiving a light dose of cortisone during and immediately after the treatment. When patients suffer from epileptic seizures treatment with antiepileptic medication iare necessary. This treatment should not be stopped immediately after treatment, and will continue even after the treatment under EEG control for some time.

Relapse growth

Depending on the completeness of tumor resection, it depends on the recurrence of untreated residual tumor. It is found in about 13% after complete and in up to 85% by incomplete removal of a tumor regrowth. In malignant forms or multiple meningiomas, the recurrence rate is significantly higher.Regardless of the resectability of the tumor, there is a need for regular follow-up imaging, which must be assessed also by neurosurgeons. Re-operation of renewable meningiomas is possible. In cases of unfavorable locations, which again allows only partial removal, one find a model of multimodal therapies with the greatest possible surgical removal and subsequent radiosurgery application.