Many patients with meningiomas seem to have a genetic defect on chromosome number 22. Schwannomas are usually benign and slow-growing. One of the most common types is known as a vestibular schwannoma, or acoustic neuroma. Another common schwannomas causes facial paralysis. Acoustic Neuromas .
Acoustic neuromas are schwannomas that involve the eighth cranial nerve.
The eighth cranial nerve is responsible for balance and hearing. These tumors occur most commonly in people between 30 and 50 years old but can occur anytime. Metastatic Brain Tumors Cancerous tumors that spread to the brain from other parts of the body, such as the lung, are said to be metastatic. Tumor cells spread to the brain through the bloodstream. In more than half of all metastatic brain cancer, the tumors are found throughout the brain and are not localized to one particular spot, making them extremely difficult to treat.