Stereotactic radiosurgery and stereotactic body radiation therapy: An overview of technical considerations and clinical applications

Stereotactic radiosurgery (SRS) and stereotactic body radiation therapy (SBRT) are potent noninvasive means of administering high-dose radiotherapy to discreet tumor foci in cranial or extracranial locations, respectively. The two forms of treatment share certain overarching principles, namely, the use of image guidance and related treatment delivery technology for escalating the radiation dose to the tumor with as little radiation dose to the surrounding normal tissue as possible. Both methods are A achieved with a stereotactic technique, implying that external fiducial reference markers serve to align the treatment machine so that an internal lesion is targeted accurately; however, notable differences in clinical applications emerge given the vastly different anatomic and clinical considerations between cranial and extracranial target lesions.