Total skin electron therapy: a modified technique for small room linear accelerator.

ABSTRACT

OBJECTIVE: Development of a technique for treating whole-body skin using linear accelerator with electron beam energy of 6-MeV at a short treatment distance. MATERIAL AND METHODS: The 6 MeV high dose rate total skin electron irradiation mode on a linear accelerator was used. Beam profiles and percentage depth doses in the patient plane were measured for different beam angulations. RESULTS: At a treatment distance (SSD) of 292 cm and using acrylic scatterer-degrader 4mm thick, the beam penetration was calculated so that the 80% dose lied at 1.6 cm for the single beam and only 6 mm for the clinical beam. A uniform vertical profile was obtained by using 3 beams for each treatment position with gantry angles of 700, 900 and 1100. CONCLUSIONS: We could implement a modified stanford technique for total skin electron beam irradiation at a short treatment distance. Using an acrylic scatterer-degrader and three beam angulations we could produce a uniform beam in the treatment plane.