Role of radiation therapy in the treatment of carcinoma of the rectum

Radiation therapy has assumed an integral role in the treatment of rectal carcinoma. The major role is in the surgical adjuvant setting in which the addition of radiation therapy can decrease the risk of local failure from up to 50% for stages B2 and C, to approximately 20%. The addition of sensitizing chemotherapy may add further benefit. Anal sphincter conservation is possible in another subset of patients with localized rectal carcinoma. Local excision and radiation therapy can achieve up to 90% local control, providing an attractive alternative to traditional ablative treatment. The other group of patients who benefited are those with locally advanced disease in whom a curative operative procedure cannot be performed. Radiation therapy can render greater than 50% of these patients operable and lead to about 25% long term local control.