Untoward side-effects of exposure of normal tissues surrounding tumor in the course of radiation treatment were avoided due to the use of a proton beam developed at the Institute of Theoretical and Experimental Physics. As a result, no post-treatment complications were observed in the surrounding tissues of the urinary bladder and rectum in 175 cancer patients (tumors of the vulva-39 and cervix uteri-136) who received a course of complex radiation treatment and preoperative irradiation.