Experience beyond the learning curve of transanal total mesorectal excision (taTME) and its effect on the incidence of anastomotic leak

BACKGROUND

The most important advancement in the surgical management of rectal cancer has been the introduction of total mesorectal excision (TME). Technical limitations to approaching mid and distal lesions remain. The recently described transanal TME makes it possible to minimize some of the difficulties by improving access. Anastomotic leak is a persistent concern after colorectal surgery no matter what technique is used. The objective of this study was to explore the impact of experience on the incidence of anastomotic leak after transanal TME. Secondary endpoints were local recurrence and margin status.

METHODS

A retrospective cohort study was conducted over a period of 3 years at a tertiary care center in Northern Ontario with high volume of rectal cancer patients. The initial 100 consecutive patients with rectal neoplasia who had transanal TME surgery were included. All cases were performed by a single team. The main outcome assessed was the incidence of anastomotic leak beyond a pre-determined learning curve, as previously established in the literature. For statistical analysis, associations between patient characteristics and outcomes were estimated using ordinary least squares and logistic regression.

RESULTS

Six cases of anastomotic leak occurred over the course of the study, the last of which occurred in the 37th patient. Relative to a baseline anastomotic leak rate of 7.8%, cumulative sum (CUSUM) analysis indicated that a 50% improvement in risk occurred at trial 50 of 85 patients that had an anastomosis performed. Two patients developed local recurrence during the study period. No correlation between learning curve and oncologic outcomes was identified.

CONCLUSIONS

Proficiency is likely to have a positive effect on the 30-day occurrence of anastomotic leak. Larger studies are required to explore the impact of experience on local recurrence.

Introduction of new techniques and technologies in surgery: Where is transanal total mesorectal excision today?

The introduction of new surgical techniques and technologies has traditionally been unregulated. In many settings surgeons frequently adopt novel procedures without following a structured program of implementation or supervision. The appearance of innovative technology played a pivotal role in the advancement of new surgical techniques during the industrial revolution. Innovation has been an essential component of surgical development, which led to contemporary surgical techniques such as minimally invasive surgery. Different initiatives have been developed to guide the safe introduction of new surgical techniques and other procedures. Those include comprehensive concepts such as the Idea, Development, Exploration, Assessment, Long-term study framework, which could be particularly relevant when reflecting on the novel transanal total mesorectal excision (taTME), introduced a decade ago. This relatively novel and complex procedure promised to overcome some of the major limitations of traditional surgical approaches for rectal cancer. According to the Idea, Development, Exploration, Assessment, Long-term study framework, taTME is in the phase of exploration, where there is an existing and increasing number of reports being published as the experience grows. The current management of rectal cancer is in a state of radical evolution, with multiple options that were not previously available. TaTME is only one technique amongst many which could be part of a rectal cancer surgeon's armamentarium; however, it requires further rigorous study and evaluation.