"Down-to-Up" transanal NOTES Total mesorectal excision for rectal cancer: Preliminary series of 9 patients.

Background: Applications for natural orifice translumenal endoscopic surgery (NOTES) to access the abdominal cavity have increased in recent years. Despite potential advantages of transanal and transcolonic NOTES for colorectal pathology, it has not been widely applied in the clinical setting. This study describes a series of nine patients for whom we performed transanal retrograde ("Down-to-Up") total mesorectal excision for rectal cancer.

Materials And Methods: Under IRB approval, informed consent was obtained from each patient with rectal adenocarcinoma. Rectosigmoidectomy with total mesorectal excision was performed using low rectal translumenal access to the mesorectal fascia and subsequent dissection in a retrograde fashion. This was achieved using either a single port device or flexible colonoscope with endoscopic instrumentation and laparoscopic assistance. This was followed by transanal extraction of the specimen and hand-sewn anastomosis.

Results: Mean operative time was 311 min. Mean hospital stay was 7.56 days. Complications occurred in two patients, and consisted of one anastomotic leakage with reoperation and one intraoperative conversion to open surgery because of impossibility to dissect the specimen. TME specimen integrity was adequate in six patients.

Conclusion: This series suggests that a retrograde mesorectal dissection via a NOTES technique is feasible in patients with rectal adenocarcinoma. This technique may act as a complimentary part of operative treatment for rectal cancer alongside other minimally invasive strategies. Long-term follow up will be needed to assess oncological results.