Preoperative and postoperative irradiation of gastrointestinal tumors

Evidence has been produced to the effect that the radiation doses sufficient to manage occult malignoma offsprings or metastases are much lower than those required to cope with primary tumors. This seems to support the assumption that five-day or twelve-day preoperative irradiation, using doses between 20 Gy and 30 Gy, is possible of a target area large enough to include adjacent lymph nodes, without any impairment of the operation proper and for much better rates of healing. This should apply particularly to rectum, stomach, and pancreas carcinomas. Preoperative irradiation should be preferred to postoperative irradiation, provided secured diagnosis, since radiosensitivity of tumor cells was found to decline and that of normal tissue to rise after surgery. Hence, therapeutic effectiveness of postoperative irradiation must be expected to decrease after each recurrence. Consultation with a radiotherapist, therefore, is recommended, prior to a recurrent operation. To improve therapeutic results, concentration at adequately furnished centres is demanded for patients with esophagus, pancreas, and anal carcinomas, resp. (author)