Healing of thoracic anastomoses after preoperative irradiation and partialresection of the esophagus in animal experiments

Background: Multimodal therapeutic concepts in cases of neoplasms of the in testinal tract entail the risk of undesirable complications with respect to healing of wounds and anastomoses. The separate steps of a combined treatm ent consisting radiation therapy and partial resection of the thoracic esop hagus were performed in animal experiments to study the effect of radiation therapy on the healing of anastomoses. Method: Adult non-purebred dogs wer e irradiated in a defined thoracic field with a Betatron (42 MeV) and subse quently underwent esophagectomy. After resection of a 2 cm segment of the e sophagus end-to-end anastomosis was performed. Different methods of irradia tion and postoperative observation times resulted in a total of 8 groups of 3 animals each. Results: Fractionated irradiation was definitely better to lerated than irradiation with a high single dosis. The temporary delay of t he anastomotic healing was documented histologically. Only one case of anas tomotic leakage occurred, and impaired wound healing was observed in only o ne animal. Conclusion: The mode of irradiation must be regarded as importan t for the clinical course. Fractionated preoperative irradiation in the are a of the thoracic esophagus does not lead to any relevant disturbance of wo und and anastomotic healing with meticulous surgical technique and adequate intensive postoperative care. The basic feasibility of surgical therapy co mbined with preoperative radiotherapy in tumors of the upper digestive trac t was confirmed by our experimental work.