Clinical trials in the management of anal cancer.

Our understandings of anal canal cancer pathogenesis and treatment have undergone significant changes due to continuing research into its pathogenesis and the results of major clinical trials conducted over the past 20 years. Anal canal cancer can be cured by combined modality chemoradiation therapy, a treatment that preserves continence and reserves abdominoperineal resection of the rectum and anal canal in patients with recurrent or residual disease after primary chemoradiotherapy. The research into more effective, less toxic therapies is continuing. Future challenges include an increasing incidence of human papillomavirus infection, the AIDS epidemic, diagnosis of early disease, and optimization of chemotherapy and radiation regimens. This article aims to provide a summary of recently completed and ongoing clinical trials in the management of anal canal cancer.