Stereotactic Body Radiation Therapy
Stereotactic Radiation Therapy is exciting technology combining the clinical expertise of the radiation oncologist with technological advancements available in radiation oncology today. Physicians and patients are most familiar with radiation therapy delivered as external beam therapy in which a relatively small amount of radiation is precisely delivered to a cancer each day for several weeks. In contrast, stereotactic radiation therapy is a technique that delivers a high dose of radiation to a cancer, as well as some benign diseases, with extreme precision in only a few treatments. “Stereotactic” refers to the computerized 3-dimensional coordinate system used to locate a cancer within the body.
Stereotactic body radiation therapy (SBRT) is a radiation therapy technique to deliver a high dose of radiation to small well-defined tumors outside of the brain. The radiation oncologist determines the appropriate use for SBRT taking into consideration the cancer type and location. Importantly, the radiation oncologist also evaluates the stage of the disease as well as the overall health of the patient. SBRT is typically used in the following situations:
- early-stage non-small cell lung cancer
- cancers originating in the spine
- small areas of metastatic disease involving the liver, adrenal gland, spine
SBRT treatment planning uses complex imaging (CT scans, MRI, PET scans) to define the tumor and normal organs. The radiation oncologist identifies the specific treatment area. With the use of sophisticated computerized treatment planning, multiple radiation beams of differing intensities converge on the cancer to deliver a high dose of radiation while minimizing radiation to surrounding normal organs.
Depending on the clinical situation, patients typically receive SBRT daily for three to five treatments. Daily imaging, known as image-guided radiation therapy, ensures the accurate and precise delivery of a cancer-killing dose of radiation.