Transanal and transrectal operations for excisional surgery of the low and mid rectum (with video)

Even with considerable operator experience and expertise, surgical access from the abdomen to the mid and low rectum and mesorectum can be difficult, especially in male and obese patients. This holds true whether the approach from above is performed by laparoscopy or laparotomy. While conventional operations that include extirpation of the anal canal and sphincters of course incorporate a perineal approach for the lowermost aspect of the proctectomy, their efficiency in cephalad extension is limited by difficulties in access and visualization. Recently, the concepts behind transanal endoscopic microsurgery/operation (TEM/TEO), natural orifice translumenal endoscopic surgery (NOTES), and confined-access/single-port laparoscopy have synergized to proffer a novel in-line endoscopic approach to the lowermost portion of the rectum in the form of a transanal-transrectal portal either alone or in combination with an abdominal component. This can be done in concert with or without sphincter excision and should both enhance the quality of the surgical specimen and minimize the potential for collateral damage in dissection. While clinical experience is developing, this operative access can already be appreciated both from a technical evolutionary and a clinical benefit perspective and is evidently consistent with the oncological principles of package total mesorectal excison (TME) for neoplasia. Furthermore, while specific "ideal" devices evolve, the essential base technological components and access platforms are now widely available while the necessary skillsets either already exist or are readily attained. This state-of-the-art review aims to illustrate the principles behind what appears likely to be the next major laparoendoscopic advance in operative practice for the colorectal and pelvic surgeon.