Spinal tumors can be treated with external beam radiation therapy (EBRT). With EBRT, the radiation is delivered by a machine called a linear accelerator, or linac, which focuses a high-energy x-ray beam into the tumor site from outside the body. External beam radiation therapy includes radiation therapy (or radiotherapy) and also radiosurgery.
External Beam Radiation Therapy
In the first category, external beam radiation therapy (EBRT), the radiation is usually delivered by a machine called a linear accelerator, or linac, which focuses a high-energy x-ray beam to the tumor site from outside the body.
VMAT / RapidArc is an advanced form of IMRT that was introduced in 2007. VMAT, or volumetric modulated arc therapy, uses special software and an advanced linear accelerator to deliver treatments up to eight times faster than what was previously possible with standard radiation therapy. Unlike conventional treatments, during which the machine must rotate several times around the patient, or make repeated stops to treat the tumor from a number of different angles, VMAT / RapidArc can deliver the dose to the entire tumor in a single rotation — in as little as two minutes.
IGRT, or image-guided radiation therapy, uses sophisticated computer software to analyze a series of image scans to create a detailed, three-dimensional picture of the target area and surrounding tissue, which enables your team to view the tumor and its position in your body before and during each treatment. The scans typically are produced by computed tomography (CT scan), magnetic resonance imaging (MRI), or positron emission tomography (PET scan).
IMRT, or intensity modulated radiation therapy, involves changing the intensity of the radiation beam at various angles. At each of these angles, the intensity of the radiation is varied (modulated) and the shape of the beam is changed to match the shape of the tumor. These adjustments enable the prescribed amount of radiation to be delivered to each part of the tumor, while minimizing exposure to the surrounding healthy tissue.
SRS, or stereotactic radiosurgery, is a technique that is most commonly used for tumors in the brain or spinal column. Unlike radiotherapy, SRS is typically delivered in a maximum of five sessions using higher doses of radiation with each session. Despite the use of the word "surgery" in its name, SRS does not involve removing the tumor with a surgical blade. Instead, a focused high-intensity beam of radiation is used to target the tumor.
Until recently, radiosurgery was most often used when the patient could not undergo conventional surgery to remove the tumor(s) because of its size or location, or because the person's health was too poor for surgery. However, some physicians consider radiosurgery as the first line of treatment for some tumors.*
*Rock JP, Ryu S, Shukairy MS, Yin FF, Sharif A, Schreiber F, Abdulhak M, Kim JH, Rosenblum ML. (May;58(5):891-8. 2006)Jin JY, Chen Q, Jin R, Rock J, Anderson J, Li S, Movsas B, Ryu S. (Apr;6(2):127-33.2007)Benzil DL, Saboori M, Mogilner AY, Rocchio R, Moorthy CR. (Nov;101 Suppl 3:413-418. 2004)