Functional Recovery and Oncologic Efficacy of Robotic Versus Laparoscopy NOSE for Patients With Stage I III Left Sided Colon Cancer: A Randomized Controlled Trial

Over the past three decades, laparoscopic surgery has evolved incessantly, especially in the field of colorectal surgery. It has been widely accepted by surgeons and patients in light of the better peri-operative outcomes and analogical long-term effectiveness, compared with open surgery for colorectal cancers. However, current conventional laparoscopic colorectal surgery requires an additional abdominal incision for specimen retrieval and sometimes for intestinal reconstruction, which increases the risk of various postoperative complications, including pain, surgical site infection, incisional hernia, and injury to the epigastric artery and abdominal cutaneous nerves, and, consequently, can delay postoperative chemotherapy.

To mitigate these unfavorable outcomes, natural orifice specimen extraction (NOSE) via the anus, stomach, or vagina, was introduced. One randomized trial reported better short-term surgical outcomes, including reduced pain and lower analgesia requirements for laparoscopic NOSE colectomy, compared with conventional laparoscopic colectomy. Transanal specimen extraction has been utilized after laparoscopic colon or rectal cancer surgery and has been found to be feasible, safe, and oncologically sound in selected cases. Several multiport laparoscopic platforms are currently available to complete all NOSE procedures and reestablish intestinal continuity with a single stapled anastomosis, which has been shown to improve short-term results compared with conventional laparoscopic colectomy. However, concerns remain regarding the long-term oncologic safety (tumor cell spillage with local recurrence and long-term survival) when NOSE is used for colorectal malignancy.

A barrier to wider adoption of NOSE is technical difficulty. The mini-laparotomy, in some cases, is used to perform a majority of the operation, as in hand-assisted laparoscopy. Adoption of NOSE by surgeons who typically perform colectomies in this fashion would be faced with a steeper learning curve than surgeons who use the mini-laparotomy solely as a specimen extraction site. On that note, intracorporeal anastomosis is a prerequisite skill for those adopting NOSE. Removal of more proximal specimens, as in a right colectomy, requires the presence of a skilled endoscopist who can snare and pull the specimen endoluminally through the length of the distal gastrointestinal tract. Specimen extraction via the vagina requires a posterior colpotomy, an operative maneuver that is not typically performed by general or colorectal surgeons. Furthermore, these technical challenges are amplified by a lack of standardization of the technique.

The demands for these technical skills are more important in removing right-sided colon pathology, as compared to left-sided pathology. There are inherent anatomic factors that make NOSE for right-sided colon pathology more difficult. Right colectomy specimens extracted through the lower gastrointestinal tract via distal colotomy must travel the length of the remaining transverse, descending, and sigmoid colon, through the rectum and out of the anus using an endoscope. While this was demonstrated to be feasible in 2010 by Eshuis et al, it is inherently difficult due to the anatomically narrow and torturous sigmoid colon. In that series, extraction via colotomy failed in 2 of 10 patients due to the bulk of the specimen. This technique is still performed in some centers, though limitations related to the size of the specimen are stricter than for left-sided colon lesions. This approach has little practicality due to its significant technical challenges, hence its limited use.

Bacterial contamination is always a concern during the NOSE procedure. Most researchers strongly suggest that mechanical bowel preparation, intraoperative transanal lavage with povidone iodine solution, transluminal wound protector, and prophylactic antibiotics are applied to reduce the bacterial load. Recently, a study showed that the risk of bacterial contamination with NOSE was not significantly higher than that in conventional laparoscopic surgery. In some studies, patients who had NOSE did not experience significant postoperative morbidity or laboratory data changes, such as leukocytosis, CRP level elevation, rectal wound-related complications or leakage, than the conventional group.