anus neoplasm accounts for 2 to 4% of colorectal tumors, being more prevalent around the seventh and the eighth decades. females are mostly affected, and the ratio is 3:1. its increased prevalence amongst the population in the past years is probably related to the higher number of people that are affected by sexually transmitted diseases, mainly human papillomavirus (types 16 and 18, mostly) and/or the human immunodeficiency virus. diagnosis is based on clinical findings and anatomopathological tests. the treatment of choice is radiochemotherapy, and the rescue surgery with abdominoperineal resection is used for recurrence and persistence cases. a retrospective and prospective longitudinal observational study was performed with 11 patients diagnosed with anal neoplasm from 2004 to 2010. six (54.5%) were females and five (45.5%) were males. the incidence was higher in the sixth decade, at the mean age of 54.45 years. the most frequent histological type observed was the epidermoid carcinoma, and the most frequent cell differentiation type was the moderately differentiated. chemotharapy associated with radiotherapy was used in 81.9% of the patients, and abdominoperineal resection was necessary as a rescue surgery in 18.2% of the patients.