Update on treatment advances in combined-modality therapy for anal and rectal carcinomas.

Concurrent radiation therapy and chemotherapy is the primary treatment for patients with squamous cell tumors of the anal canal, and is also employed in the neoadjuvant setting for patients with stage II and III adenocarcinoma of the rectum. There is constant clinical study involving modifications of chemoradiotherapy regimens in an effort to maximize tumor responses while reducing normal tissue toxicity. This review will discuss established regimens as well as newer and novel treatment approaches to treatment of anal and rectal cancer.