Stereotactic Radiation Therapy
Closely related to SRS, Stereotactic Radiation Therapy (SRT) consists of multiple or “fractionated” doses of focused radiation on the abnormal tissue of a tumor site over the course of several days or even weeks.
This form of radiation therapy is commonly used when a tumor is near an anatomical structure that is especially sensitive to high doses of radiation. In any radiation therapy technique a small area of healthy cells around the tumor, known as the margin, receives some degree of radiation. Each time a cell receives radiation, the cell is damaged. Healthy cells, however, are far better equipped to repair this damage than the abnormal tissue of tumor cells. The SRT treatment uses less radiation at any given time, and is spread out over a longer duration to allow these healthy cells time to repair themselves, while hitting the tumor site with enough radiation to sufficiently damage and destroy abnormal tumor cells.