A schwannoma is a benign nerve sheath tumor composed of Schwann cells. It is nothing but the tumor of the nerve sheath, tissue covering the nerves.

This kind of tumor is not often cancerous. If cancerous, they are termed as malignant schwannoma. They can occur in any part of the body. The common sites, where the schwannoma invade are the Sciatic nerve, Brachial Plexus and Sacral plexus.

The difference between benign tumors and malignant tumors is to be understood.

The benign tumors are not cancerous cells. They do not spread to other parts. But when it hits sensitive areas, it can become life threatening.

When it is removed, it rarely occurs. Very rarely, there is a chance of recurrence of this turning to malignant.

Whereas, the malignant brain tumor is itself very dangerous. They grow rapidly and invade the surrounding tissues. In rare cases, the cancerous cells break away from the malignant tumor and spread to the other parts of the spinal cord or even to other parts of the body. This condition is termed as metastasis.

When the cancerous cell doesn’t extend to other healthy tissues and invade it. In such cases, the growth persists within a particular layer of tissue, such kind of malignant tumor is known as encapsulated.

The brain tumors are classified into two:

The tumors that begin in the brain tissue are known as primary brain tumors. The secondary brain tumors are so named when the tumor spreads to brain from any other parts or organs of the body. This kind of tumor is also known as metastatic tumor.

Symptoms of brain tumor

The most common symptoms seen in persons afflicted with brain tumor are headaches (that occurs more often in the morning), nausea or vomiting, irrelevant speech or disturbance in vision or hearing. Has change in mood and concentration, Lack of memory, seizures, numbness or tingling in the arms or legs.

Clinical manifestations of primary brain tumors

Patients commonly present with a sub acute progressive neurologic deficit exhibiting either focal signs or personality changes. Prior mental changes or seizures may antedate tumor diagnosis. Clinical symptoms may occur abruptly with seizures or with sudden deficits secondary to tumor haemorrhage.

MRI scans often define more extensive tumor involvement than is indicated on the CT scan.

Malignant astrocytoma can arise in the brain stem, cerebellum or spinal cord in addition to the more common locations within the white matter of the cerebral hemispheres.

Treatment

Confirmation of histology by biopsy should be performed in most patients; debulking (to remove part of the tumor) of tumor is recommended if the tumor is located in an area that permits an extensive operation. Large tumor resections are more likely than biopsies to disclose small glioblastoma tumor foci within anaplastic astrocytoma.

The conventional treatment includes surgery, chemotherapy and radiotherapy.