[Effect of multi-fractionation in radiotherapy of rectal cancer]

The paper is concerned with the substantiation of multifractionated gamma-beam therapy and the results of the use of this regimen in radiotherapy of rectal cancer. The authors have proposed the following scheme of irradiation: a single focal dose of 2 Gy is delivered not once a day as in routine fractionation but twice a day with a 4-hour interval. A radiotherapeutic course has been divided into 3 stages of 5 days each with 5-day intervals in-between. The course total focal dose was 60 Gy, "time-dose-fractionation" factors--140, the equivalent total dose--83 Gy. Statistically significant improvement of immediate results and a decrease in the number and expression of radiation reactions were noted. Earlier (as compared to routine fractionation) appearance of a symptomatic effect and the reduction of a time-period of a radiotherapeutic course in bed-days by 30% were also noted.