Clinical physics, applicator choice, technique, and equipment for electron intraoperative radiation therapy.

IORT has been a widely used modality since the 1980s. The initial euphoria experienced at the beginning, however, has subsided, with the result that most centers still practicing IORT are academic institutions. The reason for the reduction in IORT performed at community hospitals is partly related to the method of treatment--namely, transporting the patient from the OR to the radiation therapy department. The advent of mobile linear accelerators, which require little or no shielding and can therefore be used in most OR rooms, is likely to reiginite interest in this modality. There are currently six new centers in the United States that practice IORT with a mobile linear accelerator and more than that in Europe.