Clinical experience with the 22-MeV microtron at the National Cancer Center Hospital.

Experience with the 22-MeV microtron is presented. The maintenance and ease of operability of the system are satisfactory. The physical characteristics showed many clinical advantages. Fundamental measurement of dose distribution and depth dose curves were performed and clinically applied. The two-gantry system is very satisfactory and effective for irradiation by photons and electrons to treat many patients per day. The facility for intraoperative radiotherapy and the physical conditions for total body irradiation are also sufficient because of the well-designed building layout and the systematized facility with the microtron system.