Residual, recurrent, or unresectable gastrointestinal cancer. Role of radiation in single or combined modality treatment.

When conventional modalities of external beam irradiation and chemotherapy +/- resection are used in the treatment of locally advanced gastrointestinal malignancies, although useful palliation can be achieved in many patients, cure and long-term survival is infrequent. Aggressive combined modality approaches have recently encorporated irradiation boost techniques with intraoperative electrons or intraoperative or transcatheter brachytherapy. Both local control and long-term survival appear to be improved when compared with results achieved with conventional treatment. Randomized trials are needed to determine if the observed differences are real or due to differences in case selection.