First-line treatment of locally advanced anal canal squamous cell carcinomas (AC-SCC) has evolved from the abdominoperineal resection resulting in permanent colostomies to definitive concurrent chemoradiotherapy, with surgery reserved for salvage. Publication of small but practice-changing chemoradiotherapy studies in the second half of the 1970s prompted the conduction of large phase III randomized controlled trials consequences of which increased our ability to deliver systemic chemotherapy more effectively and reduce treatment-related toxicity rates by utilizing more sophisticated radiotherapy techniques. This article aims to review the design and outcomes of currently accessible phase III randomized controlled chemoradiotherapy trials of AC-SCC.   

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Erkan Topkan, MD

Baskent University Medical Faculty, Department of Radiation Oncology, 01120, Adana, TURKEY