Stereotactic radio theray (SRT) or stereotactic radio surgery (SRS) is a specialized way to deliver radiation to the cancer patients to kill off their cancer cells. This type of radiation differs from the normal external radiation therapy in a way that it can be used to precisely damage the cancer cells by delivering a few sessions of high dose radiation than to provide low dose of greater number of sessions.

SRT can be effectively used to treat small tumors of the brain and other functional abnormalities. Each session of SRT is conducted on an outpatient basis. Depending on the size of the tumour, its location and the amount of radiation needed, only a single or just above two sessions may be required.

SRT procedure involves determination of the precise coordinates that needs to be targeted, immobilization of the patient, focus of the highly powerful radiation and final imaging to confirm the location of the tumor and the effect of radiation.