---

Background: The presence of small intestine in the radiation field during pelvic cancers treatment causes an interruption in radiotherapy. A non-invasive method was developed to exclude small intestine during conventional radiotherapy. Materials and Methods: The incidence of the radiation therapy interruption is highly dependent upon the area of the small intestine included in the portals and its absorbed dose. In order to investigate the radiation therapy interruption and the resulting elongation of the total treatment time, 35 patients suffering from pelvic cancers were selected and randomly assigned to control and study groups. All the patients were treated in prone position. In the 18 patients in the study group, a commercially available water bag was inserted between patient abdomen and treatment couch. Other 17 patients in the control group underwent similar therapy without water bag. Results: The total treatment time was shown to be 1.52 days shorter in the study group with a statistically significant difference (p<0.003). Conclusion: Due to the lack of the early morbidities during radiotherapy, it is concluded that the current method helps to optimize total treatment time by preventing interruption of radiation therapy.