Progress in the treatment of locally advanced clinically resectable rectal cancer.

There have been significant developments in the adjuvant treatment of locally advanced clinically resectable (T3 and/or N+) rectal cancer. Postoperative systemic chemotherapy plus concurrent pelvic irradiation (chemoradiation) significantly improves local control and survival compared with surgery alone. The German Rectal Cancer Trial confirmed that when chemoradiation is delivered preoperatively there is a significant decrease in acute and late toxicity and a corresponding increase in local control and sphincter preservation. Despite these advances, controversies remain. Among these controversies are the role of short-course radiation, whether postoperative adjuvant chemotherapy is necessary for all patients, and if the type of surgery after chemoradiation can be modified based on tumor response. Are there more accurate imaging techniques and/or molecular markers to help identify patients with positive pelvic nodes with the goal of reducing the chance of overtreatment with preoperative therapy. Will more effective systemic agents both improve outcome and modify the need for pelvic irradiation? This review examines the advances in chemoradiation as well as addresses these and other opportunities for improvement.