Natural orifice total mesorectal excision using transanal port combined with single-port laparoscopy through stoma site: lessons from a cadaveric study

Ji Won Park, MD, Young Suk Kim, MD, Dae Kyung Sohn, PhD, MD, Sung Chan Park, MD, Samin Hong, MD, Hyung Jin Kim, MD, Seong Taek Oh, PhD, MD, Jae Hwan Oh, PhD, MD

National Cancer Center, Goyang, Republic of Korea

Background: Single-port laparoscopic total mesorectal excision is challenging and technically demanding. Exposure and mobilization of the most distal part of rectum are especially difficult. The purpose of this study was to evaluate the feasibility of transanal approach to perform total mesorectal excision using laparoscopy in human cadavers.

Methods: A total of 12 cadavers underwent laparoscopic low anterior resection using transanal port combined with single-port laparoscopy through stoma site. The technique comprises the following: (1) full-thickness circumferential incision about 1cm above the dentate line; (2) rectal lumen was closed with a purse-string suture; (3) a multiple instrument access single-port was placed in the anus; (4) the rectum was mobilized cephalad with conventional laparoscopic instruments to the level of anterior peritoneal reflection; (5) after placing the lower right quadrant port as diverting stoma site, single-port laparoscopic mobilization of left colon and splenic flexure was performed; (6) specimen was delivered transanally or transabdominally and transected; (7) intestinal continuity was restored by hand-sewn coloanal anastomosis and diverting ileostomy was created. Macroscopic quality of total mesorectal excision and intraoperative events were assessed.

Results: This procedure was performed on 12 human cadavers (Male: Female=11:1). The median procedure time was 120 minutes (range, 70-165 minutes). The average length of the resected specimen was 34.7 cm (standard deviation, 6.9 cm). The quality of the total mesorectal excision specimen was complete in 7 cases (58%) and nearly complete in 5 cases (42%) and there was no incomplete quality. Intraoperative complications developed in 3 cases (25%); two urethral injuries and one urethral injury with bladder laceration.

Conclusions: This preliminary experimental study shows that transanal total mesorectal excision with single-port laparoscopy can be feasible in human cadaver. It provides adequate rectal dissection. However, this procedure can lead to inadvertent complications, such as urethral injury. Meticulous dissection with caution is required during anterior rectal dissection in male patients.

Session: Poster Presentation

Program Number: P530