Salvage abdomino-perineal resection is justified in case of failure of the conservative treatment of a cancer of the anal canal. This surgery must be offered if surgery could be complete. In case of R0 resection, more than a patient on two will be alive after 5 years. The rate of perineal complication is important and gives proof to accomplish associated procedure to fill up the perineal cavity as muscular flap taken from the abdominal wall, the perineal colostomy that avoids the iliac colostomy or the simple flap of gracilis. This linked procedure allows to diminish the length of healing and improves postoperative time.