Abdominoperineal excision or extralevator abdominoperineal excision: which is the best oncological treatment?

Surgery of tumors of the lower third of the rectum is particularly difficult due to the complex anatomy of the pelvis, which can lead to an incomplete radical resection. Abdominoperineal excision (APE) is the operation of choice for tumors of the low rectum that infiltrate levatorani or sphincter muscles. Regardless, APE causes an important morbidity, a higher incidence of circumferential resection margin (CRM) infiltration, iatrogenic tumor perforation incidence and worsens the mesorectum quality due to the conicity induced during surgery while dissection between both distal mesorectum and levatorani planes is performed. An extralevator abdominoperineal excision (ELAPE), which involves a broader resection of the pelvic floor muscles, would theoretically reduce the risk of CRM infiltration and tumor perforation rate, independently from the position (prone vs. supine) or the approach (open vs. laparoscopic). This review is focused on the analysis of the scientific evidence published so far comparing both techniques, APE or ELAPE. In spite of some publications observe a possible benefit in terms of reduction in CRM involvement, iatrogenic perforations or local recurrence, there is not enough evidence to affirm the superiority of ELAPE compared to conventional APE in terms of oncological results. In general, similar rates of postoperative complications are described for both techniques. Further prospective, controlled and randomized studies are needed to conclude which of the two techniques is the best oncological treatment.