Moscow hospital-based proton therapy facility design.

An innovative design for a hospital-based proton therapy facility is described here in two versions: a single level (3600 m2) and a three-level plan (700-720 m2). The facility is designed to have 5 to 6 treatment rooms working simultaneously and independently of each other. The accelerator is a 250 MeV H-synchrotron, which produces a small external beam capable of pencil-beam scanning treatments. The small emittance of the beam yields cost savings in the size and weight of the magnets and the amount of concrete shielding. The beam delivery systems, including an isocentric gantry, are designed to use elements that are well known and thoroughly tested. Initial cost of a facility using this new design is estimated to be only 25-30% higher than construction of a facility delivering conventional photon treatments.