[Radiotherapy for carcinoma of digestive organs]

Clinical results of intraoperative radiotherapy (IOR) applied to carcinomas of the stomach, pancreas, and rectum were reported. In stomach cancer, the 5-year survival rates of patients treated by operation alone were 93.0% for stage I, 61.2% for stage II, 36.8% for stage III and 0% for stage IV. On the other hand, the 5-year survival rates of patients treated by IOR were 90.2% for stage I, 77.0% for stage II, 54.4% for stage III and 15.3% for stage IV. It has been demonstrated that IOR has definite effects on locally advanced gastric cancer. In pancreatic cancer, the median survival times for all patients treated by operation alone, IOR and IOR+ external beams were 3.5 months, 4.5 months and 8 months respectively. The median survival times of stage III patients treated by operation alone, IOR and IOR+ external beams were 5.5 months, 5.5 months and 12 months respectively. Our clinical results suggest that prolongation of life can be expected in patients who are treated by IOR followed by external beams and stage III is best indicated. In rectal cancer, it was found that stage IV as classified according to the rules for colorectal cancer studies in Japan is best indicated for IOR from the analysis of the survival figures. In stage IV patients, those who received operation alone could not survive more than 50 months while about 50% of those who were treated by IOR are alive 50 months after the treatment.