Role of radiation therapy in neoadjuvant era in patients with locally advanced rectal cancer

Abstract

Surgery remains the primary determinant of cure in patients with localized rectal cancer, and total mesorectal excision is now widely accepted as standard of care. The widespread implementation of neoadjuvant short-course radiotherapy (RT) or long-course chemoradiotherapy (CRT) has reduced local recurrence rates from 25% to 40% to less than 10%; Preoperative RT in resectable rectal cancer has a number of potential advantages, most importantly reducing local recurrence, and down-staging effect. In this article making a comprehensive literature review searching the reliable medical data bases of PubMed and Cochrane we present all available information on the role of radiation therapy alone or in combination with chemotherapy in preoperative setting of rectal cancer. Data reported show that in locally advanced rectal cancer the addition of radiation therapy or CRT pre surgically has significantly improved sphincter prevention surgery. Moreover, the addition of chemotherapy to radiation therapy in preoperative setting has significantly improved pathologic complete response rate and loco-regional control rate without improvement in sphincter preserving surgery. Finally, the results of recently published randomized trials have shown a significant improvement of pre- vs postoperative CRT on local control; however, there was no effect on overall survival.

Keywords: Locally advanced; Neoadjuvant treatment; Preoperative treatment; Radiation therapy; Rectal cancer.