The Institute for Advanced Radiation Oncology

Disease Site Specific Treatment

Brain Tumors

Radiation therapy for tumors of the brain or central nervous system involves the delivery of high-energy radiation through several treatment methods.

» External radiotherapy, which focuses primarily on the tumor.
» Stereotactic radiosurgery, whose advanced capabilities allows precise targeting of high doses of radiation at the tumor during one treatment session.

Providing a Coordinated Approach to Brain Tumor Treatment

At Monmouth Medical Center’s Institute for Advanced Radiation Oncology, the Neuroscience Institute is led by a team of highly experienced and skilled neurosurgeons and radiation oncologists that offers a coordinated approach to radiosurgery for the treatment of benign or metastatic brain tumors.

How Radiosurgery Works
Radiosurgery is not surgery, but is a special, focal form of radiation. It does not remove the tumor or lesion, but it distorts the DNA of the tumor cells. The cells then lose their ability to reproduce and retain fluids.

This treatment allows precisely focused, high-dose radiation beams to be delivered to a small brain tumor (usually 1½ inches or less in diameter) in a single treatment session.

Because radiosurgery is radiation and not surgery, the tumor can be located in an area of the brain or spinal cord that might be considered inoperable.

Using special computer planning, this treatment minimizes the amount of radiation received by normal brain tissue.
If the treatment is delivered in one session, it is called stereotactic radiosurgery. If it is provided in multiple sessions, it is called fractionated radiosurgery.

Stereotactic radiosurgery is used for the following purposes:

• As a local “boost” following conventional radiation therapy.
• For recurrent tumors when the patient has already received the maximum safe dose of conventional radiation therapy.
• As a substitute for surgery for benign tumors (such as a pituitary, pineal region or acoustic tumor).
• For metastatic brain tumors.

Stereotactic radiosurgery is limited to the head and neck region as these areas can be immobilized with skeletal fixation devices that completely restrict the head’s movement, permitting the most precise and accurate treatment.

A patient is fitted with a head frame, which also is used during the treatment planning process when CT and/or MRI scans are done to obtain information necessary for treatment. Once the planning is completed, treatment can begin.

Utilizing a linear accelerator-based system, treatment involves the delivery of a single, high-energy beam that is computer-shaped to the tumor. The patient is positioned on a sliding bed around which the linear accelerator circles. The linear accelerator directs arcs of radioactive photon beams at the tumor. The pattern of the arc is computer-matched to the tumor’s shape. This reduces the dose delivered to surrounding normal tissue.

Since stereotactic radiosurgery doesn’t actually remove the tumor or lesion, shrinking of closing off of the structure occurs over a period of time, depending on the type of tumor or stage of disease.

When Re-Irradiation is Possible
Radiation kills normal cells as well as tumor cells. Since brain tissue cannot replace itself, the effects of radiation are cumulative. Only so many normal cells can be killed before severe results occur. For this reason, re-treatment with conventional fractionated radiation is not often recommended.

However, re-irradiation is possible in selected circumstances with radiosurgery. It depends on the tumor’s location and its relation to critical brain tissue, when the previous radiation was given, the amount of radiation originally given, the type of tumor and the age of the patient.

Metastatic brain tumors may be re-irradiated because the initial treatment usually involves less than the maximally prescribed dose.

Detailed information on disease-specific treatment is available under the Patient Information and Education section.

Gamma Knife: Proven Technology for Brain Tumor Surgery

Monmouth Medical Center will soon become equipped with Gamma Knife technology, which has a longstanding record of success in treating smaller tumors and lesions of the brain.

The Gamma Knife is not a knife at all, but a stereotactic radiosurgical device that uses multiple beams of radiation that converge in three dimensions to focus with precision on small tumors in the brain. As a result, it is able to “cut through” to tumors, blood vessel malformations and other brain abnormalities located in the deepest regions in the brain without the risks of open surgery.

The Gamma Knife has been available for 30 years with substantial research and follow-up studies that demonstrate proven treatment with successful outcomes.

[ top ]