Evaluation of the learning curve of transanal total mesorectal excision: single-centre experience

Introduction
Transanal total mesorectal excision (TaTME) has been recently proposed to overcome the difficulties of the standard TME approach, allowing better visualization and dissection of the mesorectal fascia. Although TaTME seems very promising, the evidence and body of knowledge on achieving proficiency in performing it are still sparse.

Aim
To evaluate the learning curve of TaTME based on a single centre’s experience.

Material and methods
Consecutive patients undergoing TaTME since 2014 in a tertiary referral department were included in the study. All procedures were performed by one experienced surgeon. CUSUM curve analyses were performed to evaluate learning curves.

Results
Sixty-six patients underwent TaTME. After analysis of postoperative morbidity rate, intraoperative adverse effects and operative time, we estimated that 40 cases are needed to achieve TaTME proficiency. Subsequently, patients were divided into two groups: before (40 patients) and after overcoming the learning curve (26 patients). Group 1 had higher readmission (p = 0.041) and complication rates (p = 0.019). There were no statistically significant differences in terms of intraoperative adverse effects, length of stay or pathological quality of the specimen.

Conclusions
Transanal total mesorectal excision is a promising yet technically demanding procedure and requires at least 40 cases to complete the learning curve. More data are needed to introduce it as a standard procedure for low rectal cancer treatment.