External Beam Radiation

Sometimes tumors can move between treatments. Image-guided radiation therapy, or IGRT, helps pinpoint the precise location of the tumor in order to deliver the radiation to the cancer.

How Does it Work?

• You will undergo a CT scan as part of your treatment process.
• On the day of your treatment, you will have another CT scan, ultrasound, or X-ray to pinpoint the exact location of the tumor on that day.
• Your radiation oncologist will use the new scan to target the tumor and avoid treating nearby healthy tissue.
• In some cases, your doctor may implant a tiny marker in or near the tumor to help pinpoint its location for IGRT.
• The images from your planning scan and your day of treatment scan are transmitted to a computer in the treatment room. This allows your radiation oncologist to compare the earlier images with those taken immediately before your radiation treatment.
• Radiation beams are adjusted according to what the images show, enabling the most accurate treatment of the tumor.

Three-dimensional conformal radiation therapy, or 3D-CRT, uses computers and special imaging techniques to show the size, shape, and location of a tumor.

How Does it Work?

• During 3D-CRT, the radiation beams are very precisely directed. This means other tissue located near the tissue receives less radiation during treatment. The result is you heal more quickly.
• Your radiation oncologist will use CT scans, MRI scans, or PET scans to create detailed, 3D representations of the tumor and surrounding organs.
• Then the radiation beams will be precisely tailored to the size and shape of your tumor using custom shaping blocks.

Intensity-modulated radiation therapy, or IMRT, is a specialized form of 3D-CRT that allows radiation to be more exactly shaped to fit the tumor.

How Does it Work?

• During IMRT, the radiation beams are very precisely directed. This means other tissue located near the tumor receives less radiation during treatment. The result is you heal more quickly.
• IMRT also allows a higher dose of radiation to be delivered to the tumor, increasing the chance of a cure.
• Your radiation oncologist will use CT scans, MRI scans, or PET scans to create detailed, 3D representations of the tumor and surrounding organs.
• The radiation beams will be precisely tailored to the size and shape of your tumor. The radiation beam can be broken up into many smaller beams, called beamlets.
• The intensity of each beamlet can be adjusted individually, to more accurately treat your tumor.

Stereotactic radiosurgery (SRS) uses specialized equipment to position you with such great accuracy that we can precisely and safely deliver large radiation doses to a brain tumor, while almost completely sparing nearby healthy brain tissue.

In addition to treating some cancers, radiosurgery can also be used to treat malformations in the brain’s blood vessels and certain noncancerous (benign) neurologic conditions.

What Can I Expect?

• A single treatment session
• No surgical incision, so only local anesthesia is used
• Low risk of infection
• No need to shave your head
• Few, if any, side effects
• The ability to return home the same day as the procedure

One to two weeks before you have stereotactic radiosurgery, you will have a special MRI to help identify the location of your tumor.

On the day of your procedure you can expect:

• The treatment team will attach a rigid frame to your head, using small ceramic pins, to make sure there is no movement during treatment.
• A new scan will be made and combined with your prior scans to provide the most accurate information possible to your doctors.
• During the procedure, a linear accelerator with precisely focused X-ray beams will rotate around you.
• The table that you are on may be moved so that the target is hit from different angles.
• The entire process takes about a half day. You should have someone accompany you to provide transportation home, as you will not be allowed to drive a vehicle until the following day.

How Does it Work?

• Stereotactic radiosurgery uses a large dose of radiation to destroy tumor cells in areas of the brain that might not be reachable with regular surgery.
• Custom designed narrow X-ray beams are focused from several different angles and deliver a high dose of radiation to a small, targeted area.
• Sometimes a high dose of stereotactic radiotherapy can be focused upon a tumor outside the brain and given in a few treatments (typically three to eight).

Stereotactic radiotherapy allows us to precisely focus beams of radiation to destroy certain types of tumors and spare more healthy tissue. In addition to treating some cancers, radiosurgery can also be used to treat malformations in the brain’s blood vessels and certain noncancerous (benign) neurologic conditions.

What Can I Expect?

• The treatment team will fit you with a head frame or other secure immobilization device to be sure you do not move during the procedure.
• You will most likely receive a single dose of radiotherapy, although certain situations may require more than one dose.
• The treatment is painless, and afterward you may return home to your normal activities.

How Does it Work?

• Stereotactic radiotherapy uses a beam so precise that it targets only the cancerous tumor. This enables your radiation oncologist to spare more healthy tissue.
• Sometimes a high dose of stereotactic radiotherapy can be focused upon a tumor outside the brain and given in a few treatments (typically three to eight).