Controversies in Radiation for Upper Rectal Cancers

Abstract

Over the past few decades substantial improvement has occurred in the diagnosis and treatment of rectal cancers. This disease requires the close cooperation of a multidisciplinary team, including radiologists, gastroenterologists, surgeons, medical oncologists, and radiation oncologists, to provide optimum treatment with minimal morbidity. The widespread use of total mesorectal excision (TME) and improvements in chemotherapy and radiation delivery have resulted in decreases in locoregional recurrence. Large randomized studies have shown a benefit with the use of preoperative chemoradiation for most patients with transmural and/or node-positive disease. Controversy remains, however, regarding whether this treatment paradigm should be applied uniformly to all patients regardless of tumor location. As the risk of local recurrence decreases with high rectal tumors and the benefit in terms of sphincter preservation is not applicable to this subgroup of patients, up-front surgery to allow for more accurate pathologic staging prior to making final treatment decisions is recommended. In patients with pathologically staged T3,N0,M0 tumors of the upper rectum who have undergone TME with 12 or more nodes removed, the addition of chemoradiation has very little benefit.