Stereotactic radiosurgery (SRS) is a technology by which multiple intersecting beams of radiation are directed at the tumor such that the point of intersection of the beams receives a lethal dose of radiation, while tissue in the path of any single beam remains unharmed. There are several types and brands, the most common being Gamma Knife®, LINAC and CyberKnife®.
•
SRS is non-invasive and is usually performed as a single outpatient procedure. However, confirmation that the tumor has been killed or neutralized is often not possible for several months post-treatment.
•
SRS is typically the primary intervention for treating metastatic tumors, which are usually responsive to radiation. However, since high doses of radiation may be required to kill each tumor, in the case of multiple or recurring mets it is common for the patient to have reached the point at which further radiation is contraindicated (“toxic threshold”). It also may be limited in cases with large or deep-seated tumors. In these cases only surgery or chemotherapy may be considered as treatment options.
Brain Cancer
