Treating Brain Tumors

Tumors of the brain may be benign (non-cancerous) or malignant (cancerous). Benign brain tumors need to be treated because they can cause serious health problems by pressing on sensitive areas of the brain. Additionally, some benign tumors can become malignant over time. Malignant tumors are classified as brain cancer whether they originate in the brain or have spread to the brain from cancers in other parts of the body. Because the brain is so complex, treatment to this area might have long-term implications to the nervous system or other organs. If you or someone you love has been diagnosed with a brain tumor, we recommend learning about all your treatment options before making a decision.

The advantages of proton therapy over standard X-ray radiation

Too much radiation to the brain has been known to cause neurological dysfunction and even death. Compared with X-ray radiation therapy, proton therapy results in less exposure to normal brain tissue, eyes, and the optic nerve. This is because protons precisely target a tumor and do not continue beyond it the way X-rays do. Less healthy brain tissue is irradiated with proton therapy than with X-ray/IMRT^1,2, therefore patients experience fewer side effects.

The extra exposure to healthy tissue that X-rays/IMRT deliver can be as much as getting 75,000 to 450,000 dental X-rays.

Click image above to enlarge.

Compared to other forms of radiation therapy, proton therapy delivers less radiation to normal brain tissue. The extra exposure to healthy tissue that X-rays/IMRT deliver can be as much as getting 75,000 to 450,000 dental X-rays. This additional radiation increases the risk of side effects.

Compared with X-ray radiation therapy, proton therapy results in less exposure to normal brain tissue, eyes, and the optic nerve.

Brain tumors most appropriate for proton therapy³

• Low-grade gliomas
• Grade III gliomas (anaplastic astrocytomas)
• Meningiomas
• Ependymomas
• Medulloblastomas
• Pineoblastomas
• Supratentorial PNET
• Germ cell tumors

Arteriovenous malformations (AVMs) of the brain can also be treated using protons. In treating large and inoperable AVMs, clinical evidence shows protons to be associated with improved outcomes (the “obliteration” of the malformation) and reduced side effects when compared with X-rays.^4,5

What to expect when getting treated

Proton therapy is safe, non-invasive, and painless. Depending on the patient's diagnosis, treatments are usually given five days a week for a period of four to eight weeks. The time spent actually delivering the protons to the tumor is about one minute, but a treatment session for brain cancer can range from 30 to 45 minutes due to time spent positioning the patient for this precise treatment. In most cases patients continue with normal activities before and after treatment.

Treatment options at a glance

• Proton therapy – A non-invasive treatment that uses proton radiation to kill cancer cells by preventing them from dividing and growing.

  Considerations: Proton therapy delivers less radiation to the non-target brain (defined as the normal brain minus the tumor area) than X-ray radiation. This decrease in dose to normal brain tissues may retain better overall brain function and reduce the likelihood of secondary tumors in the future.¹

   

• Standard X-ray radiation – A commonly used radiation treatment to kill cancer cells by preventing them from dividing and growing. Common options include: intensity-modulated radiation therapy (IMRT), Gamma Knife^®, and CyberKnife^®.

  Considerations: Tissues in the brain are very sensitive. Radiating healthy brain tissue can result in loss of memory, cognitive skills, and mobility.

  
  

  Proton therapy delivers less radiation to the non-target brain (defined as the normal brain minus the tumor area) than X-ray radiation. This decrease in dose to normal brain tissues may retain better overall brain function and reduce the likelihood of secondary tumors in the future.¹

• Surgery – Surgery to the brain requires the removal of a part of the skull. This procedure is called a craniotomy. After the surgeon has removed the tumor and affected cells, the patient’s own bone will be used to cover the opening in the skull.

  Considerations: Depending on the size and location of the tumor, risks include infection, bleeding, and nerve damage.

   

• Chemotherapy – The use of drugs to kill or alter the cancer cells in the brain, often used in combination with other therapies.

  Considerations: Chemotherapy drugs have limited effectiveness in treating brain tumors. However, when used in combination with other treatments, their effectiveness increases.

When treating tumors in the brain, a combination of treatments is often used.

References

1. Vernimmen FJ, Harris JK, Wilson JA, Melvill R, Smit BJ, Slabbert JP. Stereotactic proton beam therapy of skull base meningiomas. Int J Radiat Oncol Biol Phys. 2001;49(1):99-105.
2. Bolsi A, Fogliata A, Cozzi L. Radiotherapy of small intracranial tumours with different advanced techniques using photon and proton beams: a treatment planning study. Radiother Oncol. 2003;68(1):1-14.
3. Data on file, ProCure; 2009.
4. Silander H, Pellettieri L, Enblad P, et al. Fractionated, stereotactic proton beam treatment of cerebral arteriovenous malformations. Acta Neurol Scand. 2003;109(2):85-90.
5. Vernimmen FJ. Talk presented at: Particle Therapy Co-Operative Group Meeting 47; May 19-24; Jacksonville, FL. 15 years of proton radiosurgery experience at the Ithemba Labs, long-term results for AVMs, meningiomas, and acoustic neuromas. OncoLink Web site: http://www.oncolink.org/conferences/article.cfm?c=3&s=51&ss=272&id=1754. Published May 26, 2008. Accessed September 10, 2010.