NOTES transanal rectal cancer resection using transanal endoscopic microsurgery
BACKGROUND: With a rapidly expanding international registry of cases, Natural Orifice Translumenal Endoscopic Surgery (NOTES) continues to be held as the next phase in minimally invasive surgery. While pure and hybrid transvaginal procedures predominate clinically, there is growing interest in transanal NOTES as it may potentially minimize the morbidity of colorectal resections. METHODS: Extensive experimental and clinical evidence support the fact that septic complications from intentional colotomy during colorectal procedures are minimized with adequate closure. Other advantages of transanal NOTES include the favorable ergonomics of transanal endoscopy and availability of Transanal Endoscopic Microsurgery (TEM) as a particularly well-suited endoscopic platform. RESULTS: Since the description of transanal endoscopic rectosigmoid resection using TEM in 2007, extensive evaluation in swine acute and survival studies has demonstrated that this technique is feasible, safe, and easily reproducible using conventional instrumentation. Validation of this approach in human cadavers has confirmed the feasibility of transanal total mesorectal excision using a standardized technique. In the first clinical report published to date, transanal endoscopic rectosigmoid resection with TME was performed using laparoscopic assistance in a female patient with a stage III mid-rectal cancer treated with neoadjuvant therapy. CONCLUSIONS: Although preliminary, these results highlight the potential impact of this approach in minimizing the morbidity associated with rectal cancer resection, and warrant further investigation with respect to safety and long-term oncologic outcomes. Improvements in the design of currently available endoscopic platforms and instrumentation will be important for widespread clinical application in the future, and if pure NOTES transanal resection remains the ultimate goal.