A systematic review of transabdominal levator division during abdominoperineal excision of the rectum (APER)

The aim of the present study was to evaluate the surgical technique, short-term oncological and perioperative outcomes for the transabdominal division of the levator ani muscles during abdominoperineal excision of the rectum (APER). A systematic review was performed to identify studies reporting on transabdominal division of the levator ani during APER. A comprehensive literature search was performed using a combination of free-text terms and controlled vocabulary when applicable on the following databases: MEDLINE, EMBASE, Science Citation Index Expanded and Cochrane Central Register of Controlled Trials in the Cochrane Library. The search period was from January 1945 to December 2015. The following search headings were used: "transabdominal", "transpelvic", "abdominal" or "pelvic" combined with either "levator" or "extralevator" and with "abdominoperineal". Nine publications were identified reporting on 99 participants. The male/female distribution was 1.44:1, respectively, and the mean age was 56.6 (30-77) years. All tumours were less than 5 cm from the anal verge. The preoperative radiological staging was T2 in 18% of cases, T3 in 53.5% and T4 in 28.5%. Transabdominal division of the levators was performed laparoscopically in 55 cases, robotically in 34 and open in 10. The mean operating time was 255 (177-640) min. Mean intraoperative blood loss was 140 (92-500) ml. There were no conversions to open. Circumferential resection margins were positive in two cases, and there was one intraoperative perforation. Mean post-operative length of stay was 9.3 (3-67) days. Follow-up (from 0 to 31 months) revealed 19 perineal wound infections, 15 cases of sexual dysfunction and 7 cases of urinary retention. There was no mortality and 1 readmission. Transabdominal division of the levators during APER is feasible and reproducible, with acceptable perioperative and good early oncological outcomes. Further comparative studies are needed.