Stereotactic radiosurgery and hypofractionated stereotactic radiotherapy: normal tissue dose constraints of the central nervous system.

Department of Radiation Oncology, University of Rochester Medical Center, Rochester, NY 14642, USA.
Cancer Treatment Reviews (Impact Factor: 6.47). 05/2011; 37(7):567-78. DOI: 10.1016/j.ctrv.2011.04.004
Source: PubMed

ABSTRACT Single-fraction stereotactic radiosurgery (SRS) and hypofractionated stereotactic radiotherapy (SRT) are radiation planning and delivery techniques used for the treatment of intracranial and spine/spinal cord tumors and targets. For cranial SRS and SRT, critical normal tissues/structures include the brainstem, cranial nerves, cochlea and normal brain parenchyma. For spine SRS/SRT, critical normal tissues/structures include the spinal cord, cauda equina as well as neighboring organs. This paper reviews clinical studies investigating central nervous system dose tolerances after cranial or spinal SRS/SRT. The impact of dose, volume, fractionation, and other relevant clinic-pathologic variables are discussed, as are limitations of the published data.

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