Brachytherapy in the treatment of colorectal malignancies.

By precisely delivering a single, high dose fraction of intraoperative radiation under direct visualization while excluding surrounding normal dose-limiting tissues, IORT has improved the therapeutic ratio of tumor control to morbidity. Both IOERT and HDR-IORT represent effective means of delivering this therapy, and either may be chosen with equal confidence, depending upon the facilities available, physician preference, and the clinical situation. The extraordinary efforts often required in the management of these highly selected patients is justified by the improvement achieved in the enhanced local control rates and increased cure rates. Preoperative chemoradiation therapy followed by gross total resection and IORT affords the patient the highest likelihood of local control and survival. The importance of aggressive surgery in achieving gross total resection with pathologically negative margins is reflected by the dramatic correlation reported between margin status and local control. The high complication rate associated with this multidisciplinary therapy is, no doubt, multifactorial and may be attributed to the advanced disease state at presentation and the intensive multidisciplinary treatments administered. In an effort to eradicate disease and prolong survival, many consider these elevated complication rates acceptable, particularly in light of the complexity of these cases, as well as the morbidity and mortality associated with persistent disease in the pelvis.