Treatment of the Primary Tumor in Anal Canal Cancers.

Radical concurrent chemoradiotherapy with 5-fluorouracil and mitomycin C (MMC) remains the standard of care for squamous cell carcinoma of the anus. Phase III trials over 2 decades have used combined radiation doses of 50 to 60 Gy with concurrent fluoropyrimidines, MMC, or cisplatin in various doses and schedules. Modern radiotherapy techniques allow the production of highly conformal plans, decreasing radiation doses to the organs at risk and ensuring a shorter overall treatment time without the need for treatment breaks. These techniques offer the potential to improve compliance and even escalate doses of radiation.