TOTAL-BODY SUPERFICIAL ELECTRON-BEAM THERAPY USING A MULTIPLE-FIELD PENDULUM-ARC TECHNIQUE

A technique using pendulum-arc rotation is presented for electron-beam treatment of generalized superficial malignancies. The technique consists of six arcing fields symmetrically dispersed around the body surface for circumferential coverage. The arc angle is selected to scan the height of the body fully. Beam uniformity within 10% over a height of 180 cm is achieved at a treatment distance of 385 cm. Randophantom dosimetry, using an 8 MeV electron beam degraded by 3/8 in Plexiglas, indicates a surface dose uniformly within ±7% over most of the body surface. Underdosages occur at regions obstructed by adjacent body parts.