Stereotactic Body Radiation Therapy, Part II: Clinical Experience and Rationale
The spatial accuracy, conformality, and high dose gradients of stereotactic radiosurgery
are characteristics which make it well suited for use in treating a variety of extracranial
targets. In particular, use of stereotactic body radiation therapy (SBRT) may be
advantageous in any clinical situation in which a dose-response relationship for a well
defined tumor coexists with surrounding dose-limiting normal tissues. Given that lung
and liver are some of the more challenging locations for achieving spatial accuracy with
conventional treatments, tumors within these locations dominate current clinical
experience, although ESR has been used in multiple other organ systems. Published
early results demonstrate excellent response rates and remarkably low toxicity using a
variety of hypofractionated dose regimens and a variety of localization and
immobilization techniques. This portion of the course will provide an overview of the
variety of clinical situations in which ESR has been used along with a description of
some methods used for dose selection. Emphasis will be placed on improvements in
clinically relevant patient outcomes which are potentially achievable with this exciting
new modality.