Source of Support: None, Conflict of Interest: None
Fifty patients with cervix cancer were treated with teletherapy (15 MV photons, 2 Gy daily) up to the dose of 40-45 Gy. Low dose-rate (two fractions) brachytherapy followed teletherapy up to the dose of 50-60 Gy. Total dose distributions were calculated on the basis of simple summation of brachytherapy and teletherapy doses. A linear quadratic model was used to calculate biologically effective doses (BED) in the tumour and critical organs. BED'S were higher than total doses in the rectum by 24% to 2% and those in the bladder by 11% to 1 %. The clinical observation in a group of patients showed late reactions in the rectum, which occurred more frequently than those in the bladder, where BED was closer to physical dose than in rectum.