<prompt> A 55 year old male, working as a hotel cook, has four dependent family members. He has been diagnosed with an early stage squamous cell cancer of anal canal. He has more than 60 chance of cure. The BEST treatment option is:Abdominoperineal resectionCombined surgery and radiotherapyCombined chemotherapy and radiotherapyChemotherapy alone  <response>: Nigro regimen is referred to combined chemotherapy and radiotherapy used for primary treatment of malignant tumors of the anal canal. Ref: Bailey Love 25e, page 1269; Schwaz 9e, Page 1053. 