COMPLICATIONS OF BRAIN RADIATION

Treatment of Brain Tumors and AVMs
Symptoms of Brain Radiation Necrosis

TREATMENT OF BRAIN TUMORS AND AVMS

    In the United States, approximately 35,000 new intracranial tumor cases are diagnosed each year—15,000 are primary brain tumors, the remainder spread from tumors in other locations. Many are treated with radiation therapy to destroy or shrink them, with the incidence of visual, pituitary and brain tissue damage as high as 38 percent. For malignant tumors, new or continuing symptoms may be the result of the original tumor spreading (metastasis), radiation damage, or the development of new cancer.

    Radiation is also used to eliminate arteriovenous malformations (AVMs), defective blood vessel formations. Post radiosurgical swelling can be reduced with hyperbaric oxygen therapy.

     SYMPTOMS OF BRAIN RADIATION NECROSIS

    Radiation treatment of large brain areas can result in memory loss, impaired thinking ability (cognition), reduced sexual desire, hormonal changes, personality disturbance, sleep disruption, poor cold tolerance, nausea, unsteadiness, and visual changes. Half of these patients will show brain shrinkage or increase in the non-tissue (ventricle) space. Inflammation, blood vessel damage, swelling, brain shrinkage, and necrosis (an area of dead cells within the radiation site), may occur months or years after radiation.

    Damage to the blood vessels appears to be the cause of the most devasting effects. Radiation of structures outside the brain may result in brain exposure. Treatment of cancers of the facial skin, nose, mouth, ears, and eyes may lead to late-onset brain effects and dementia.

    There is extreme difficulty in determining whether a patient’s symptoms are the result of tumor recurrence, metastasis (spreading outside of the original site), or radiation necrosis. Because the site where necrosis most frequently occurs is where radiation was used to destroy tumor tissue, the symptoms often mimic those previously experienced before tumor treatment.

Identifiable radiation-induced necrosis occurs in 20% to 25% of patients treated for cancerous brain tumors. For large volume tumors or whole brain radiation, 40% of patients, and for localized irradiation, 3% to 9% of patients, may suffer such necrosis, seen 3 months to years after completion of treatment. Significant neurological damage can result even when treatment is not extensive.

The objective of any treatment has to be evaluated—success, often described as the ‘not having the tumor recur,’ is probably more accurately described in terms of longevity and quality of life.

    Traditional treatments (usually corticosteroids) for radionecrosis are also dangerous, treat the symptoms rather than the underlying cause, and typically not administered until the patient complains of symptoms. When corticosteroids are used to control swelling, only about 35% of patients respond.

    If steroids fail, the damaged portion of the brain may be surgically removed. If steroids are not effective, and surgery is not a choice, treating symptoms used to be the only choice —and one that did not stop the underlying damage process.

Hyperbaric Oxygen Therapy is the only known treatment potentially capable of reversing brain radiation necrosis, with some studies showing a 90 percent success rate.

    For more information about what hyperbaric oxygen therapy may be able to do for you, contact:

©2008 Florida Oxygen