A schwannoma tumor is a tumor made of Schwann cells; Schwann cells make up the myelin sheath (or covering) of nerve cells. In more cases than not, they are benign, meaning noncancerous, but there are instances of malignant schwannomas that do cause cancer. Actually, this is so rare that only about 1% become malignant. Schwannoma tumors can grow into very large masses, sometimes pushing the nerve it is inhabiting up against a nearby bone, causing damage. Schwannoma tumors can be located anywhere along the nervous system, but most often occur in the brain, the ear, throughout the trunk, and around the peripheral nerves. Treatment always varies, depending on the size and location of the tumor, the health of the patient, and the symptoms that the tumor causes.
In 99% of the cases, a schwannoma tumor is sporadic and not hereditary, but in that other 1%–the malignant 1% — it can be the result of a disease called neurofibromatosis (a condition in which nerve tissue grows tumors). These malignant tumors occur most often in the major nerve of the leg, the nerves at the top of the arm, or the lower back. In the other cases (benign cases), the cause is not known.
Depending on the location of the schwannoma tumor, the symptoms will present themselves differently. Pain, weakness, and numbness in the area are common symptoms. When it is located in the ear (called a vestibular schwannoma tumor), there will be a ringing noise, called tinnitus, deafness, and possibly loss of balance and coordination if it pushes up against the brainstem and cranial nerves.
Treatment and Complications
While surgical intervention is the most common treatment for schwannomas, there are different classifications within this field used to remove them. A neurosurgeon is responsible for performing the surgery because the tumors are in the nerves—called neural tumors; choosing a highly skilled and qualified neurosurgeon should be one of your top priorities because if one nerve or even one nerve fiber is damaged or cut, serious life-long damage could result. The result of surgery could be numbness (only temporary if a nerve fiber hasn’t been damaged), tingling, pin-and-needles sensations, sensitivity, or other symptoms of nerve dysfunction. A permanent complication that could result from this type of surgery would be paralysis. In a big majority of patients, pain and weakness associated with the tumor before surgery is relieved after surgery is accomplished; the time frame in which this happens depends on how bad the symptoms were preoperatively. In very rare cases does neuropathic pain result from a surgery.
Radiotherapy. This type of radiation is often used if the schwannoma is fairly large; it uses radiation to shrink the tumor, usually until it reaches a suitable enough size to be removed through surgery; this decreases the risk of cutting or damaging any nerves.
Keeping Tabs. If the tumor isn’t associated with any symptoms in an individual and if it is not malignant, it is not always necessary to have surgery. However, if this is the case, it is important for the doctor to regularly monitor the tumor to make sure it doesn’t produce any changes that could endanger the patient. Usually an MRI or CT scan will be done to keep track of the tumor’s size. If symptoms or discomfort do appear over time, surgery will be recommended to get rid of the tumor.
Possibility of Recurrence
If the complete tumor is successfully removed, the chance is very small for a recurrence. Regular MRI scans are usually not recommended if the tumor is removed completely. If the schwannoma does come back, it just means that it wasn’t removed in full the first time around, whether it was left on accident or because the surgeon simply couldn’t get to it all; even microscopic traces of the tumor could cause a recurrence.