[Analysis of morbidity from simultaneous 5-fluorouracil therapy and radiation therapy in advanced gastrointestinal tumors. Report of results].

Simultaneous application of 5-fluorouracil and radiotherapy is generally accepted in the treatment of gastrointestinal tumours. However, in 10 patients with metastatic gastrointestinal tumours we observed intolerable toxicity during this combined treatment regimen. Because of gastrointestinal and haematological toxicity the combined modality was interrupted in all patients. Given sequentially, this regimen was tolerated. Our experience indicates that an intolerable high rate of toxicity has to be taken into consideration in case of the simultaneous combination of 5-fluorouracil and radiotherapy.