Feasibility of transanal total mesorectal excision (taTME) using the Medrobotics Flex® System
The use of transanal total mesorectal excision (taTME) for treatment of rectal cancer is growing, but anatomic constraints prevent access to the proximal rectum with rigid instruments. The articulated instrumentation of current surgical robots is promising in overcoming these limitations, but the bulky size of current platforms inhibits the proximal reach of dissection. Flexible robotic systems could overcome these constraints while maintaining a stable platform for dissection. The goal of this study was to evaluate feasibility of performing taTME using the semi-robotic Flex® System (Medrobotics Corp., Raynham, MA) in human cadavers.
taTME was performed by two surgeons in six fresh human cadaveric specimens using the Flex® System, with or without transabdominal laparoscopic assistance. Both mid- and low-rectal lesions were simulated. Metrics including quality of visualization, maintenance of pneumorectum, maneuverability of instruments, effectiveness of pursestring suture placement, and dissection in an anatomically correct plane were evaluated.
The semi-robotic endoluminal platform allowed for excellent visualization, insufflation, and dissection during taTME. Adequate pursestring occlusion of the rectum was achieved in all six cases. In cadavers with simulated mid-rectal lesions (N = 4), dissection and anterior peritoneal entry was achieved in all cases, with abdominal assistance utilized in two of four cases. In cadavers with simulated low-rectal lesions (N = 2), dissection was incomplete and aborted due to difficulty maneuvering instruments in close proximity to the rigid transanal port.
Use of the Flex® system for taTME is feasible for mid-rectal dissection. Advantages over the traditional multi-armed robot include longer reach of instruments with the ability to dissect up to 17 cm from the anal verge, as well as tactile feedback. The current design of the flexible platform does not permit safe dissection in the distal rectum, although this constraint may be resolved with future adjustments to the equipment.
KeywordsTransanal total mesorectal excision (taTME) Proctectomy Robotic surgery Rectal cancer Natural orifice transluminal endoscopic surgery (NOTES) Robotic transanal total mesorectal excision
Compliance with ethical standards
Drs. Obias and Sylla are consultants for Medrobotics. Drs. Carmichael, D’Andrea, and Skancke have no conflicts of interest or financial ties to disclose.
Supplementary material 1 (MP4 142060 kb)
- 2.Marijnen CA, Kapiteijn E, van de Velde CJ, Martijn H, Steup WH, Wiggers T, Kranenbarg EK, Leer JW, Cooperative Investigators of the Dutch Colorectal Cancer Group (2002) Acute side effects and complications after short-term preoperative radiotherapy combined with total mesorectal excision in primary rectal cancer: report of a multicenter randomized trial. J Clin Oncol 20:817–825CrossRefGoogle Scholar
- 3.Snijders H, Wouters M, van Leersum N, Kolfschoten N, Henneman D, de Vries A, Tollenaar R, Bonsing B (2012) Meta-analysis of the risk for anastomotic leakage, the postoperative mortality caused by leakage in relation to the overall postoperative mortality. Eur J Surg Oncol 38:1013–1019CrossRefGoogle Scholar
- 4.Jeong S, Park J, Nam B, Kim S, Kang S, Lim S, Choi H, Kim D, Chang H, Kim D, Jung K, Kim T, Kang G, Chie E, Kim S, Sohn D, Kim D, Kim J, Lee H, Kim J, Oh J (2014) Open versus laparoscopic surgery for mid-rectal or low-rectal cancer after neoadjuvant chemoradiotherapy (COREAN trial): survival outcomes of an open-label, non-inferiority, randomised controlled trial. Lancet Oncol 15:767–774CrossRefGoogle Scholar
- 5.Ohtani H, Tamamori Y, Azuma T, Mori Y, Nishiguchi Y, Maeda K, Hirakawa K (2011) A meta-analysis of the short- and long-term results of randomized controlled trials that compared laparoscopy-assisted and conventional open surgery for rectal cancer. J Gastrointest Surg 15:1375–1385CrossRefGoogle Scholar
- 6.Kang S, Park J, Jeong S, Nam B, Choi H, Kim D, Lim S, Lee T, Kim D, Kim J, Chang H, Lee H, Kim S, Jung K, Hong Y, Kim J, Sohn D, Kim D, Oh J (2010) Open versus laparoscopic surgery for mid or low rectal cancer after neoadjuvant chemoradiotherapy (COREAN trial): short-term outcomes of an open-label randomised controlled trial. Lancet Oncol 11:637–645CrossRefGoogle Scholar
- 8.Guillou P, Quirke P, Thorpe H, Walker J, Jayne D, Smith A, Heath R, Brown J, MRC CLASICC trial group (2005) Short-term endpoints of conventional versus laparoscopic-assisted surgery in patients with colorectal cancer (MRC CLASICC trial): multicentre, randomised controlled trial. Lancet 365:1718–1726CrossRefGoogle Scholar
- 9.van der Pas M, Haglind E, Cuesta M, Fürst A, Lacy A, Hop W, Bonjer H, COlorectal cancer Laparoscopic or Open Resection II (COLOR II) Study Group (2013) Laparoscopic versus open surgery for rectal cancer (COLOR II): short-term outcomes of a randomised, phase 3 trial. Lancet Oncol 14:210–218CrossRefGoogle Scholar
- 11.Fleshman J, Branda M, Sargent D, Boller A, George V, Abbas M, Peters W, Maun D, Chang G, Herline A, Fichera A, Mutch M, Wexner S, Whiteford M, Marks J, Birnbaum E, Margolin D, Larson D, Marcello P, Posner M, Read T, Monson J, Wren S, Pisters P, Nelson H (2015) Effect of laparoscopic-assisted resection vs open resection of stage II or III rectal cancer on pathologic outcomes: the ACOSOG Z6051 randomized clinical trial. JAMA 314:1356–1364CrossRefGoogle Scholar
- 13.Collinson F, Jayne D, Pigazzi A, Tsang C, Barrie J, Edlin R, Garbett C, Guillou P, Holloway I, Howard H, Marshall H, McCabe C, Pavitt S, Quirke P, Rivers C, Brown J (2012) An international, multicentre, prospective, randomised, controlled, unblinded, parallel-group trial of robotic-assisted versus standard laparoscopic surgery for the curative treatment of rectal cancer. Int J Colorectal Dis 27:233–241CrossRefGoogle Scholar
- 15.Jayne D, Pigazzi A, Marshall H, Croft J, Corrigan N, Copeland J, Quirke P, West N, Rautio T, Thomassen N, Tilney H, Gudgeon M, Bianchi P, Edlin R, Hulme C, Brown J (2017) Effect of robotic-assisted vs conventional laparoscopic surgery on risk of conversion to open laparotomy among patients undergoing resection for rectal cancer: the ROLARR Randomized Clinical Trial. JAMA 318:1569–1580CrossRefGoogle Scholar
- 16.Sylla P, Sohn D, Cizginer S, Konuk Y, Turner B, Gee D, Willingham F, Hsu M, Mino-Kenudson M, Brugge W, Rattner D (2010) Survival study of natural orifice translumenal endoscopic surgery for rectosigmoid resection using transanal endoscopic microsurgery with or without transgastric endoscopic assistance in a swine model. Surg Endosc 24:2022–2030CrossRefGoogle Scholar
- 18.Telem D, Han K, Kim M, Ajari I, Sohn D, Woods K, Kapur V, Sbeih M, Perretta S, Rattner D, Sylla P (2013) Transanal rectosigmoid resection via natural orifice translumenal endoscopic surgery (NOTES) with total mesorectal excision in a large human cadaver series. Surg Endosc 27:74–80CrossRefGoogle Scholar
- 20.Penna M, Hompes R, Arnold S, Wynn G, Austin R, Warusavitarne J, Moran B, Hanna G, Mortensen N, Tekkis P (2018) Incidence and risk factors for anastomotic failure in 1594 patients treated by transanal total mesorectal excision: results from the international TaTME registry. Ann Surg. https://doi.org/10.1097/sla.0000000000002653 CrossRefGoogle Scholar
- 35.Jafari M, Carmichael J, Kopchok G, Pigazzi A (2017) A pilot study to evaluate a flexible robot for transanal surgeryGoogle Scholar