Which of the following will be your treatment of choice for squamous cell carcinoma of anal canal in a 46 year old healthy man who does not require a colostomy?

Chemoradiation is the treatment of choice for all anal canal tumors. Commonly used drugs are 5 fluorouracil, mitomycin, bleomycin, cis platinum and doxorubicin. Chemotherapy is given initially which is followed by radiotherapy. In frail patients with advanced lesions a defunctioning colostomy may be the only available therapy to relieve the patient of distressing symptoms such as incontinence. Small squamous cell carcinoma of anal verge are treated using a wide local excision leaving a margin of at least 2.5cm of tissue all round. Ref: Bailey and Love's Sho Practice of Surgery, 24th edn, Page 1271