Transanal total mesorectal excision for low rectal cancer: a case-matched study comparing TaTME versus standard laparoscopic TME

Laparoscopic total mesorectal excision versus transanal total mesorectal excision for mid and low rectal cancer: A systematic review and meta-analysis

BACKGROUND

Laparoscopic total mesorectal excision (LaTME) and transanal total mesorectal excision (TaTME) are popular mid and low rectal cancer trends. However, there is currently no systematic comparison between LaTME and TaTME of mid and low rectal cancer. Therefore, we systematically study the perioperative and pathological outcomes of LaTME and TaTME in mid and low rectal cancer.

METHODS

Articles included searching through the Embase, Cochrane Library, PubMed, Medline, and Web of science for articles on LaTME and TaTME. We calculated pooled standard mean difference (SMD), relative risk (RR), and 95% confidence intervals (CIs). The protocol for this review has been registered on PROSPERO (CRD42022380067).

RESULTS

There are 8761 participants included in 33 articles. Compared with TaTME, patients who underwent LaTME had no statistical difference in operation time (OP), estimated blood loss (EBL), postoperative hospital stay, over complications, intraoperative complications, postoperative complications, anastomotic stenosis, wound infection, circumferential resection margin, distal resection margin, major low anterior resection syndrom, lymph node yield, loop ileostomy, and diverting ileostomy. There are similarities between LaTME and TaTME for 2-year DFS rate, 2-year OS rate, distant metastasis rat, and local recurrence rate. However, patients who underwent LaTME had less anastomotic leak rates (RR 0.82; 95% CI: 0.70-0.97; I2 = 10.6%, P = .019) but TaTME had less end colostomy (RR 1.96; 95% CI: 1.19-3.23; I2 = 0%, P = .008).

CONCLUSION

This study comprehensively and systematically evaluated the differences in safety and effectiveness between LaTME and TaTME in the treatment of mid and low rectal cancer through meta-analysis. Patients who underwent LaTME had less anastomotic leak rate but TaTME had less end colostomy. There is no difference in other aspects. Of course, in the future, more scientific and rigorous conclusions need to be drawn from multi-center RCT research.

A systematic review and meta-analysis of minimally invasive total mesorectal excision versus transanal total mesorectal excision for mid and low rectal cancer

Background

Minimally invasive total mesorectal excision (MiTME) and transanal total mesorectal excision (TaTME) are popular trends in mid and low rectal cancer. However, there is currently no systematic comparison between MiTME and TaTME of mid and low-rectal cancer. Therefore, we systematically study the perioperative and pathological outcomes of MiTME and TaTME in mid and low rectal cancer.

Methods

We have searched the Embase, Cochrane Library, PubMed, Medline, and Web of Science for articles on MiTME (robotic or laparoscopic total mesorectal excision) and TaTME (transanal total mesorectal excision). We calculated pooled standard mean difference (SMD), relative risk (RR), and 95% confidence intervals (CIs). The protocol for this review has been registered on PROSPERO (CRD42022374141).

Results

There are 11010 patients including 39 articles. Compared with TaTME, patients who underwent MiTME had no statistical difference in operation time (SMD -0.14; CI -0.31 to 0.33; I²⁼84.7%, P=0.116), estimated blood loss (SMD 0.05; CI -0.05 to 0.14; I²⁼48%, P=0.338), postoperative hospital stay (RR 0.08; CI -0.07 to 0.22; I²⁼0%, P=0.308), over complications (RR 0.98; CI 0.88 to 1.08; I²⁼25.4%, P=0.644), intraoperative complications (RR 0.94; CI 0.69 to 1.29; I²⁼31.1%, P=0.712), postoperative complications (RR 0.98; CI 0.87 to 1.11; I²⁼16.1%, P=0.789), anastomotic stenosis (RR 0.85; CI 0.73 to 0.98; I²⁼7.4%, P=0.564), wound infection (RR 1.08; CI 0.65 to 1.81; I²⁼1.9%, P=0.755), circumferential resection margin (RR 1.10; CI 0.91 to 1.34; I²⁼0%, P=0.322), distal resection margin (RR 1.49; CI 0.73 to 3.05; I²⁼0%, P=0.272), major low anterior resection syndrome (RR 0.93; CI 0.79 to 1.10; I²⁼0%, P=0.386), lymph node yield (SMD 0.06; CI -0.04 to 0.17; I²⁼39.6%, P=0.249), 2-year DFS rate (RR 0.99; CI 0.88 to 1.11; I²⁼0%, P = 0.816), 2-year OS rate (RR 1.00; CI 0.90 to 1.11; I²⁼0%, P = 0.969), distant metastasis rate (RR 0.47; CI 0.17 to 1.29; I²⁼0%, P = 0.143), and local recurrence rate (RR 1.49; CI 0.75 to 2.97; I²⁼0%, P = 0.250). However, patients who underwent MiTME had fewer anastomotic leak rates (SMD -0.38; CI -0.59 to -0.17; I²⁼19.0%, P<0.0001).

Conclusion

This study comprehensively and systematically evaluated the safety and efficacy of MiTME and TaTME in the treatment of mid to low-rectal cancer through meta-analysis. There is no difference between the two except for patients with MiTME who have a lower anastomotic leakage rate, which provides some evidence-based reference for clinical practice. Of course, in the future, more scientific and rigorous conclusions need to be drawn from multi-center RCT research.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO, identifier CRD42022374141.

A longer pelvis is associated with longer operative time in transanal total mesorectal excision (TME) but not in laparoscopic TME. Results from a retrospective cohort study

Introduction

A narrow pelvis, obesity, and bulky low rectal tumor are perceived as risk factors for intraoperative difficulties during total mesorectal excision (TME), particularly in the laparoscopic approach. A transanal approach has been developed to overcome the difficulties encountered during laparoscopic TME. There is no clear definition of a narrow pelvis that would guide preoperative surgical planning.

Aim

To evaluate different MRI-based pelvic measurements in patients undergoing TME to identify factors predictive of intraoperative difficulties in transabdominal compared to the transanal approach.

Material and methods

A retrospective analysis of 48 patients treated with laparoscopic TME and 62 with transanal TME for rectal tumors was performed. Multiple logistic regressions analyzed demographic, tumor, and pelvimetry factors that correlate with intraoperative difficulties measured as intraoperative blood loss, operation time, and perioperative complications in both surgical approaches.

Results

Multivariate analysis showed that age was associated with higher blood loss (OR = 1.09, 95% CI: 1.00-1.18, p = 0.038), male gender (OR = 0.13, 95% CI: 0.02-0.86, p = 0.029) and body mass index with longer operating time (OR = 1.32, 95% CI: 1.06-1.64, p = 0.010) in the LAR group. Multivariate analysis showed that age increased the odds of intraoperative blood loss > 100 ml (OR = 1.08, 95% CI: 1.02-1.15, p = 0.013), and pelvic length > 119 mm increased operating time (OR = 5.76, 95% CI: 1.33-25.01, p = 0.016) in the TaTME group.

Conclusions

Pelvic measurements are not associated with intraoperative difficulties in LAR. Longer pelvis was associated with longer operative time in TaTME.

Innovation in gastrointestinal surgery: the evolution of minimally invasive surgery-a narrative review

Background

Minimally invasive (MI) surgery has revolutionised surgery, becoming the standard of care in many countries around the globe. Observed benefits over traditional open surgery include reduced pain, shorter hospital stay, and decreased recovery time. Gastrointestinal surgery in particular was an early adaptor to both laparoscopic and robotic surgery. Within this review, we provide a comprehensive overview of the evolution of minimally invasive gastrointestinal surgery and a critical outlook on the evidence surrounding its effectiveness and safety.

Methods

A literature review was conducted to identify relevant articles for the topic of this review. The literature search was performed using Medical Subject Heading terms on PubMed. The methodology for evidence synthesis was in line with the four steps for narrative reviews outlined in current literature. The key words used were minimally invasive, robotic, laparoscopic colorectal, colon, rectal surgery.

Conclusion

The introduction of minimally surgery has revolutionised patient care. Despite the evidence supporting this technique in gastrointestinal surgery, several controversies remain. Here we discuss some of them; the lack of high level evidence regarding the oncological outcomes of TaTME and lack of supporting evidence for robotic colorectalrectal surgery and upper GI surgery. These controversies open pathways for future research opportunities with RCTs focusing on comparing robotic to laparoscopic with different primary outcomes including ergonomics and surgeon comfort.

Meta-analysis of transanal vs laparoscopic total mesorectal excision of low rectal cancer: Importance of appropriate patient selection

BACKGROUND

Achieving a clear resection margins for low rectal cancer is technically challenging. Transanal approach to total mesorectal excision (TME) was introduced in order to address the challenges associated with the laparoscopic approach in treating low rectal cancers. However, previous meta-analyses have included mixed population with mid and low rectal tumours when comparing both approaches which has made the interpretation of the real differences between two approaches in treating low rectal cancer difficult.

AIM

To investigate the outcomes of transanal TME (TaTME) and laparoscopic TME (LaTME) in patients with low rectal cancer.

METHODS

A comprehensive systematic review of comparative studies was performed in line with Preferred Reporting Items for Systematic Reviews and Meta-Analyses standards. Intraoperative and postoperative complications, anastomotic leak, R0 resection, completeness of mesorectal excision, circumferential resection margin (CRM), distal resection margin (DRM), harvested lymph nodes, and operation time were the investigated outcome measures.

RESULTS

We included twelve comparative studies enrolling 969 patients comparing TaTME (n = 969) and LaTME (n = 476) in patients with low rectal tumours. TaTME was associated with significantly lower risk of postoperative complications (OR: 0.74, P = 0.04), anastomotic leak (OR: 0.59, P = 0.02), and conversion to an open procedure (OR: 0.29, P = 0.002) in comparison with LaTME. Moreover, the rate of R0 resection was significantly higher in the TaTME group (OR: 1.96, P = 0.03). Nevertheless, TaTME and LaTME were comparable in terms of rate of intraoperative complications (OR: 1.87; P = 0.23), completeness of mesoractal excision (OR: 1.57, P = 0.15), harvested lymph nodes (MD: -0.05, P = 0.96), DRM (MD: -0.94; P = 0.17), CRM (MD: 1.08, P = 0.17), positive CRM (OR: 0.64, P = 0.11) and procedure time (MD: -6.99 min, P = 0.45).

CONCLUSION

Our findings indicated that for low rectal tumours, TaTME is associated with better clinical and short term oncological outcomes compared to LaTME. More randomised controlled trials are required to confirm these findings and to evaluate long term oncological and functional outcomes.

Clinical Robotic Surgery Association (India Chapter) and Indian rectal cancer expert group’s practical consensus statements for surgical management of localized and locally advanced rectal cancer

Introduction

There are standard treatment guidelines for the surgical management of rectal cancer, that are advocated by recognized physician societies. But, owing to disparities in access and affordability of various treatment options, there remains an unmet need for personalizing these international guidelines to Indian settings.

Methods

Clinical Robotic Surgery Association (CRSA) set up the Indian rectal cancer expert group, with a pre-defined selection criterion and comprised of the leading surgical oncologists and gastrointestinal surgeons managing rectal cancer in India. Following the constitution of the expert Group, members identified three areas of focus and 12 clinical questions. A thorough review of the literature was performed, and the evidence was graded as per the levels of evidence by Oxford Centre for Evidence-Based Medicine. The consensus was built using the modified Delphi methodology of consensus development. A consensus statement was accepted only if ≥75% of the experts were in agreement.

Results

Using the results of the review of the literature and experts’ opinions; the expert group members drafted and agreed on the final consensus statements, and these were classified as “strong or weak”, based on the GRADE framework.

Conclusion

The expert group adapted international guidelines for the surgical management of localized and locally advanced rectal cancer to Indian settings. It will be vital to disseminate these to the wider surgical oncologists and gastrointestinal surgeons’ community in India.

A Way to Start Transanal Total Mesorectal Excision for Rectal Cancer

Introduction The optimal rectal cancer care is achieved by a multidisciplinary approach, with a high-quality surgical resection, with complete mesorectal excision and adequate margins. New approaches like the transanal total mesorectal excision (TaTME) aim to achieve these goals, maximizing the sphincter preservation ratio, with good oncologic and functional results. This report describes a way to implement TaTME without a proctor, presents the first case series of this approach in a center experienced in rectal cancer, and compares the results with those of the international literature.

Methods We performed a retrospective study of the first 10 consecutive patients submitted to TaTME for rectal cancer at our institution. The primary outcomes were postoperative complications, pathological specimen quality and local recurrence rate. The results and performance were compared with the outcomes of a known structured program with proctorship and with the largest meta-analysis on this topic.

Results All patients had locally advanced cancer; therefore, all underwent neoadjuvant therapy. A total of 30% had postoperative complications, without mortality or re-admissions. In comparison with the structured training program referred, no differences were found in postoperative complications and reintervention rates, resulting in a similar quality of resection. Comparing these results with those of the largest meta-analysis on the subject, no differences in the postoperative complication rates were found, and very similar outcomes regarding anastomotic leaks and oncological quality of resection were registered.

Conclusion The results of this study validate the safety and effectiveness of our pathway regarding the implementation of the TaTME approach, highlighting the fact that it should be done in a center with proficiency in minimally invasive rectal surgery.

UEG and EAES rapid guideline: Systematic review, meta-analysis, GRADE assessment and evidence-informed European recommendations on TaTME for rectal cancer

BACKGROUND

Evidence and practice recommendations on the use of transanal total mesorectal excision (TaTME) for rectal cancer are conflicting.

OBJECTIVE

We aimed to summarize best evidence and develop a rapid guideline using transparent, trustworthy, and standardized methodology.

METHODS

We developed a rapid guideline in accordance with GRADE, G-I-N, and AGREE II standards. The steering group consisted of general surgeons, members of the EAES Research Committee/Guidelines Subcommittee with expertise and experience in guideline development, advanced medical statistics and evidence synthesis, biostatisticians, and a guideline methodologist. The guideline panel consisted of four general surgeons practicing colorectal surgery, a radiologist with expertise in rectal cancer, a radiation oncologist, a pathologist, and a patient representative. We conducted a systematic review and the results of evidence synthesis by means of meta-analyses were summarized in evidence tables. Recommendations were authored and published through an online authoring and publication platform (MAGICapp), with the guideline panel making use of an evidence-to-decision framework and a Delphi process to arrive at consensus.

RESULTS

This rapid guideline provides a weak recommendation for the use of TaTME over laparoscopic or robotic TME for low rectal cancer when expertise is available. Furthermore, it details evidence gaps to be addressed by future research and discusses policy considerations. The guideline, with recommendations, evidence summaries, and decision aids in user-friendly formats can also be accessed in MAGICapp: https://app.magicapp.org/#/guideline/4494 .

CONCLUSIONS

This rapid guideline provides evidence-informed trustworthy recommendations on the use of TaTME for rectal cancer.

Anastomotic leakage and chronic presacral sinus after transanal total mesorectal excision (taTME) for rectal cancer: A comparative study to laparoscopic TME

BACKGROUND

Several studies have shown that there are no significant differences in anastomotic leakage associated with Transanal total mesorectal excision (taTME) versus laparoscopic TME (lapTME) for rectal cancer; however, little is known about late anastomotic leakage, such as that primarily found in the chronic presacral sinus. We aimed to compare the occurrence of anastomotic leakage and chronic presacral sinus in rectal cancer for taTME and lapTME.

METHODS

In this retrospective cohort study, data were collected for patients with rectal cancer who underwent surgery between January 2009 and September 2019. Of the 220 patients included in this study, 182 were in the lapTME group and 38 in the taTME group. We compared factors associated with anastomotic leakage and chronic presacral sinus formation between the two groups. A binary-logistic model was used to determine the risk factors for chronic presacral sinus.

RESULTS

Anastomotic leakage occurred in six patients (15.8%) in the taTME group and 36 patients (19.7%) in the lapTME group. Chronic presacral sinus occurred in three patients (7.9%) in the taTME group and 15 patients (8.2%) in the lapTME group. There was no significant difference in anastomotic leakage or chronic presacral sinus between groups (P = 0.569 and P = 1.000, respectively). Pathologic stage III or higher was significantly associated with chronic presacral sinus formation (P = 0.006).

CONCLUSION

There were no significant differences between taTME and lapTME regarding the incidence of anastomotic leakage or chronic presacral sinus. Almost one-third of anastomotic leakages developed into chronic presacral sinus.

A systematic review and meta-analysis on complications of transanal total mesorectal excision

AIM

Transanal total mesorectal excision (TaTME) is a surgical approach for treating mid to low rectal cancer as well as other colorectal diseases. Since the procedure is difficult to master, perioperative complications of TaTME should be examined precisely, especially during the early implementation phase of this procedure. The primary aim of this review was to determine a pooled morbidity and anastomotic leakage (AL) rate after TaTME surgery, and the secondary aim was to show the completeness of reporting of complications among the included studies, as well as the correlation between completeness and reported incidence of complications.

METHOD

A systematic review of literature was conducted using Medline, Embase and Cochrane databases, searching for observational studies reporting on complications after TaTME. Studies published between 1 January 2010 and 15 October 2019 were included. Meta-analysis on the proportion of morbidity, AL and intraoperative complications was performed.

RESULTS

Forty-one studies (2446 TaTME cases), consisting of 27 noncomparative studies and 14 comparative studies, were included, after screening 1711 possible studies. The pooled rates of overall morbidity and AL were 30.0% (95% CI 26.4%-34.0%) and 6.8% (95% CI 5.2%-8.9%), respectively. Subgroup analysis showed that the morbidity rate in studies that reported 30-day results (35.5%; 95% CI 31.8%-39.4%) was significantly higher than the rate in studies that did not define the follow-up length for complications (23.4%; 95% CI 17.8%-30.1%; p = 0.003). The rates of intraoperative urethral injury, rectal injury, vaginal injury and bladder injury were 0.3% (95% CI 0.1%-1.7%), 0.4% (95% CI 0.1%-2.2%), 0.3% (95% CI 0.1%-0.8%) and 0.3% (95% CI 0.1%-1.7%), respectively.

CONCLUSION

This meta-analysis shows that pooled perioperative complication rates were within acceptable ranges. However, the significant difference in overall morbidity rate between the studies with 30-day results and the studies without a specified follow-up time, indicates a large under-reporting of complications in many studies.

Impact of Surgical Approach on Surgical Resection Quality in Mid- and Low Rectal Cancer, A Bayesian Network Meta-Analysis

AIM

To evaluate the evidence concerning the quality of surgical resection in laparoscopic (LapTME), robotic (RobTME) and transanal (TaTME) total mesorectal excision for mid-/low rectal cancer.

METHODS

A systematic literature search of the PubMed, EMBASE and Cochrane Central Register of Controlled Trials databases was performed. A Bayesian network meta-analysis was utilized to compare surgical resection involved in these 3 surgical techniques by using ADDIS software. Rates of positive circumferential resection margins (CRMs) were the primary endpoint.

RESULTS

A total of 34 articles, 2 randomized clinical trials (RCTs) and 32 non-RCTs, were included in this meta-analysis. Pooled data showed CRM positivity in 114 of 1763 LapTME procedures (6.5%), 54 of 1051 RobTME procedures (5.1%) and 60 of 1276 TaTME procedures (4.7%). There was no statistically significant difference among these 3 surgical approaches in terms of CRM involvement rates and all other surgical resection quality outcomes. The incomplete mesorectal excision rates were 9.6% (69/720) in the LapTME group, 1.9% (11/584) in the RobTME group and 5.6% (45/797) in the TaTME group. Pooled network analysis observed a higher but not statistically significant risk of incomplete mesorectum when comparing both LapTME with RobTME (OR = 1.99; 95% CI = 0.48-11.17) and LapTME with TaTME (OR = 1.90; 95% CI = 0.99-5.25). By comparison, RobTME was most likely to be ranked the best or second best in terms of CRM involvement, complete mesorectal excision, rate of distal resection margin (DRM) involvement and length of DRMs. In addition, RobTME achieved a greater mean tumor distance to the CRM than TaTME. It is worth noting that TaTME was most likely to be ranked the worst in terms of CRM involvement for intersphincteric resection of low rectal cancer.

CONCLUSION

Overall, RobTME was most likely to be ranked the best in terms of the quality of surgical resection for the treatment of mid-/low rectal cancer. TaTME should be performed with caution in the treatment of low rectal cancer.

Deep learning-based automatic surgical step recognition in intraoperative videos for transanal total mesorectal excision

BACKGROUND

Dividing a surgical procedure into a sequence of identifiable and meaningful steps facilitates intraoperative video data acquisition and storage. These efforts are especially valuable for technically challenging procedures that require intraoperative video analysis, such as transanal total mesorectal excision (TaTME); however, manual video indexing is time-consuming. Thus, in this study, we constructed an annotated video dataset for TaTME with surgical step information and evaluated the performance of a deep learning model in recognizing the surgical steps in TaTME.

METHODS

This was a single-institutional retrospective feasibility study. All TaTME intraoperative videos were divided into frames. Each frame was manually annotated as one of the following major steps: (1) purse-string closure; (2) full thickness transection of the rectal wall; (3) down-to-up dissection; (4) dissection after rendezvous; and (5) purse-string suture for stapled anastomosis. Steps 3 and 4 were each further classified into four sub-steps, specifically, for dissection of the anterior, posterior, right, and left planes. A convolutional neural network-based deep learning model, Xception, was utilized for the surgical step classification task.

RESULTS

Our dataset containing 50 TaTME videos was randomly divided into two subsets for training and testing with 40 and 10 videos, respectively. The overall accuracy obtained for all classification steps was 93.2%. By contrast, when sub-step classification was included in the performance analysis, a mean accuracy (± standard deviation) of 78% (± 5%), with a maximum accuracy of 85%, was obtained.

CONCLUSIONS

To the best of our knowledge, this is the first study based on automatic surgical step classification for TaTME. Our deep learning model self-learned and recognized the classification steps in TaTME videos with high accuracy after training. Thus, our model can be applied to a system for intraoperative guidance or for postoperative video indexing and analysis in TaTME procedures.

Short- and mid-term outcomes of transanal versus laparoscopic total mesorectal excision for low rectal cancer: a meta-analysis

Purpose

The current meta-analysis combining mid and low rectal cancer with no meta-analysis only for low rectal cancer was seen. This meta-analysis was to compare the short- and mid-term outcomes of the transanal total mesorectal excision (TaTME) vs. laparoscopic total mesorectal excision (LaTME) for low rectal cancer.

Methods

A systematic literature search was conducted using the web-based databases; China National Knowledge Infrastructure, Chinese BioMedical Database, PubMed, Embase, Cochrane Central Register of Controlled Trials, and Wanfang Database. Randomized controlled trials (RCTs) were evaluated using the Jadad scale and non-RCTs (NRCs) were evaluated using the Newcastle-Ottawa Scale.

Results

Ten studies (2 RCTs and 8 NRCs) involving 772 patients were included. Among them, 378 patients underwent TaTME and 394 patients underwent LaTME. Compared with the LaTME group, the conversion rate was low (risk ratio [RR], 0.25; 95% confidence interval [CI], 0.11–0.54; P < 0.001), the circumferential resection margin (CRM) involvement was low (RR, 0.48; 95% CI, 0.27–0.86; P = 0.010), and the hospital stay was short (mean difference, −1.72; 95% CI, −2.89 to −0.55; P = 0.004) in the TaTME group. No significant differences were seen in the mesorectal resection quality, CRM distance, distal resection margin (DRM) involvement, DRM distance, local R1 resection, intraoperative complications, morbidity, anastomotic leakage, severe morbidity, mortality, operative time, intraoperative blood loss, harvested lymph nodes, and local recurrence rate (P > 0.05).

Conclusion

The TaTME is a promising surgical technique and is fully a safe and efficacious option in managing low rectal cancer.

Total mesorectal excision - 40 years of standard of rectal cancer surgery

Total mesorectal excision (TME) was first described 40 years ago by Richard Heald. The purpose of this article is to point out importance of this surgical procedure. Starting from first attempts to surgically cure rectal carcinoma in the nineteenth century through Miles' operation at the beginning of the twentieth century results were not satisfactory due to high number of local recurrences after resections for rectal cancer. Progress in surgical technique and knowledge of anatomy and embryology of the rectum led to development of TME. Principle of TME is surprisingly simple: removal of the rectum with complete embryonic space containing lymph nodes which are site of primary dissemination of the disease. Main advantages and drawbacks of TME as well as focus on newer procedures developed from the concept of TME are presented in the form of a review.

Canadian taTME expert collaboration (CaTaCO) position statement

INTRODUCTION

Transanal total mesorectal excision (taTME) is a novel approach to surgery for rectal cancer. The technique has gained significant popularity in the surgical community due to the promising ability to overcome technical difficulties related to the access of the distal pelvis. Recently, Norwegian surgeons issued a local moratorium related to potential issues with the safety of the procedure. Early adopters of taTME in Canada have recognized the need to create guidelines for its adoption and supervision. The objective of the statement is to provide expert opinion based on the best available evidence and authors' experience.

METHODS

The procedure has been performed in Canada since 2014 at different institutions. In 2016, the first Canadian taTME congress was held in the city of Toronto, organized by two of the authors. In early 2019, a multicentric collaborative was established [The Canadian taTME expert Collaboration] which aimed at ensuring safe performance and adoption of taTME in Canada. Recently surgeons from 8 major Canadian rectal cancer centers met in the city of Toronto on December 7 of 2019, to discuss and develop a position statement. There in person, meeting was followed by 4 rounds of Delphi methodology.

RESULTS

The generated document focused on the need to ensure a unified approach among rectal cancer surgeons across the country considering its technical complexity and potential morbidity. The position statement addressed four domains: surgical setting, surgeons' requirements, patient selection, and quality assurance.

CONCLUSIONS

Authors agree transanal total mesorectal excision is technically demanding and has a significant risk for morbidity. As of now, there is uncertainty for some of the outcomes. We consider it is possible to safely adopt this operation and obtain adequate results, however for this purpose it is necessary to meet specific requirements in different domains.

Meta-analysis of transanal total mesorectal excision versus laparoscopic total mesorectal excision in management of rectal cancer

OBJECTIVES

To evaluate comparative outcomes of transanal total mesorectal excision (TaTME) and laparoscopic TME (LaTME) in patients with rectal cancer.

METHODS

We systematically searched multiple databases and bibliographic reference lists. A combination of free text and controlled vocabulary search adapted to thesaurus headings, search operators, and limits were applied. Overall intraoperative complications, overall postoperative complications, anastomotic leak, surgical site infections (SSIs), completeness of mesorectal excision, R0 resection, distal (DRM) and circumferential resection margin (CRM), number of harvested lymph nodes, and procedure time were the evaluated outcome parameters.

RESULTS

We identified 18 comparative studies reporting a total of 2048 patients evaluating outcomes of TaTME (n = 1000) and LaTME (n = 1048) in patients with rectal cancer. TaTME was associated with significantly higher number of R0 resection (OR 1.67, P = 0.01) and harvested lymph nodes (MD 1.08, P = 0.01), and lower rate of positive CRM (OR 0.67, P = 0.04) and conversion to an open procedure (OR 0.17, P < 0.00001) compared with LaTME. However, there was no significant difference in intraoperative complications (OR 1.18, P = 0.54), postoperative complications (OR 0.89, P = 0.24), anastomotic leak (OR 0.88, P = 0.42), SSIs (OR 0.64, P = 0.26), completeness of mesorectal excision (OR 1.43, P = 0.19), DRM (MD 1.87, P = 0.16), CRM (MD 0.36, P = 0.58), and procedure time (MD - 10.87, P = 0.18) between TaTME and LaTME. Moreover, for low rectal tumours, TaTME was associated with significantly lower rate of anastomotic leak and higher number of lymph nodes (MD 2.06, P = 0.002).

CONCLUSIONS

Although the meta-analysis of best available evidence (level 2) demonstrated that TaTME may be associated with better short-term oncological outcomes and similar clinical outcomes compared with LaTME, the differences between the two groups were small questioning their clinical relevance. No solid conclusions can be made due to lack of high quality randomised studies.

Clinical and oncological outcomes of single-incision vs. conventional laparoscopic surgery for rectal cancer

BACKGROUND

To evaluate the clinical and oncological outcomes of single-incision laparoscopic surgery (SILS) vs. conventional laparoscopic surgery (CLS) for patients with rectal cancer (RC) who underwent total mesorectal excision (TME) surgery.

METHODS

This was a retrospective case-control study of patients with RC operated between 12/2013 and 12/2017 in Ruijin Hospital North, Shanghai Jiaotong University School of Medicine. In total, 177 patients who underwent CLS and 51 who underwent SILS met the inclusion and exclusion criteria and were matched 1:1 using propensity score matching method (PSM).

RESULTS

Compared with the CLS group, the SILS group showed shorter operation time [105 (40) vs. 125 (55) min, P = 0.045], shorter total incision length [4 (1) vs. 6.5 (1.5) cm, P < 0.001], lower VAS score on POD2 [1 (1) vs. 2 (1), P < 0.001], shorter time to soft diet [7 (1) vs. 8 (2) days, P = 0.048], and shorter length of hospital stay [9 (2) vs. 11 (3) days, P < 0.001]. The postoperative complications were similar between two groups [1(2%) vs. 5 (9.8%), P = 0.205]. No readmissions or mortality in either group occurred within 30 days of surgery. All 102 specimens met the requirements of TME. No significant differences were observed in the pathologic outcomes between the two groups. The median follow-up period was 32.6 months in the SILS group and 36.8 months in the CLS group (P = 0.053). The 3-year disease-free survival rates and overall survival rates of the SILS and CLS groups were 89.8% vs. 96.0% (P = 0.224) and 90.9% vs. 96.9% (P = 0.146), respectively.

CONCLUSIONS

Compared with CLS, TME surgery for rectal cancer can be performed safely and effectively using the SILS technique with better cosmetic results, less postoperative pain, faster postoperative recovery, and acceptable clinical and oncological outcomes.

Transanal total mesorectal excision for rectal cancer has been suspended in Norway

Background

Transanal total mesorectal excision (TaTME) for rectal cancer has emerged as an alternative to the traditional abdominal approach. However, concerns have been raised about local recurrence. The aim of this study was to evaluate local recurrence after TaTME. Secondary aims included postoperative mortality, anastomotic leak and stoma rates.

Methods

Data on all patients who underwent TaTME were recorded and compared with those from national cohorts in the Norwegian Colorectal Cancer Registry (NCCR) and the Norwegian Registry for Gastrointestinal Surgery (NoRGast). Kaplan–Meier estimates were used to compare local recurrence.

Results

In Norway, 157 patients underwent TaTME for rectal cancer between October 2014 and October 2018. Three of seven hospitals abandoned TaTME after a total of five procedures. The local recurrence rate was 12 of 157 (7·6 per cent); eight local recurrences were multifocal or extensive. The estimated local recurrence rate at 2·4 years was 11·6 (95 per cent c.i. 6·6 to 19·9) per cent after TaTME compared with 2·4 (1·4 to 4·3) per cent in the NCCR (P &lt; 0·001). The adjusted hazard ratio was 6·71 (95 per cent c.i. 2·94 to 15·32). Anastomotic leaks resulting in reoperation occurred in 8·4 per cent of patients in the TaTME cohort compared with 4·5 per cent in NoRGast (P = 0·047). Fifty-six patients (35·7 per cent) had a stoma at latest follow-up; 39 (24·8 per cent) were permanent.

Conclusion

Anastomotic leak rates after TaTME were higher than national rates; local recurrence rates and growth patterns were unfavourable.

Functional outcomes after resections for low rectal tumors: comparison of Transanal with laparoscopic Total Mesorectal excision

Background

Aim of this study was to evaluate functional outcomes of transanal total mesorectal excision (TaTME) in comparison to conventional laparoscopic approach (LaTME) in terms of low anterior resection syndrome (LARS).

Methods

Forty-six patients who underwent total mesorectal excision for low rectal cancer between 2013 and 2017 were enrolled. Primary outcome was the severity of faecal incontinence, assessed both before the treatment and 6 months after ileostomy reversal. LARS score and Jorge-Wexner scale were utilized to analyze its severity.

Results

Twenty (87%) from TaTME and 21 (91%) from LaTME group developed LARS postoperatively. There were no significant differences between groups in terms of LARS occurrence (p = 0.63) and severity. The median Wexner score was comparable in both groups (8 [IQR: 4–12] vs 7 [3–11], p = 0.83). Univariate analysis revealed that postoperative complications were a risk factor for LARS development (p = 0.02). Perioperative outcomes, including operative time, blood loss and intraoperative adverse events did not differ significantly between groups either. Five TaTME patients developed postoperative complications, while there were morbidity 6 cases in LaTME group. Quality of mesorectal excision was comparable with 20 and 19 complete cases in TaTME and LaTME groups, respectively.

Conclusions

TaTME provided comparable outcomes in terms of functional outcomes in comparison to LaTME for total mesorectal excision in low rectal cancers. Having said that, LARS prevalence is still high and requires further evaluation of the technique.

Transanal versus laparoscopic total mesorectal excision for mid and low rectal cancer: a meta-analysis of short-term outcomes

Introduction

The benefit of transanal total mesorectal excision (TaTME) for mid and low rectal cancer is conflicting.

Aim

To assess and compare the short-term outcomes of TaTME with conventional laparoscopic total mesorectal excision (LaTME) for middle and low rectal cancer.

Material and methods

We searched PubMed, Embase and Cochrane Library databases for studies addressing TaTME versus conventional LaTME for rectal cancer between 2008 and December 2018. Randomized controlled trials (RCTs) and retrospective studies which compared TaTME with LaTME were included.

Results

Twelve retrospective case-control studies were identified, including a total of 899 patients. We did not find significant differences in overall intraoperative complications, blood loss, conversion rate, operative time, overall postoperative complication, anastomotic leakage, ileus, or urinary morbidity. Also no significant differences in oncological outcomes including circumferential resection margin (CRM), positive CRM, distal margin distance (DRM), positive DRM, quality of mesorectum, number of harvested lymph nodes, temporary stoma or local recurrence were found. Although the TaTME group had better postoperative outcomes (readmission, reoperation, length of hospital stay) on average, the difference did not reach statistical significance.

Conclusions

Transanal total mesorectal excision offers a safe and feasible alternative to LaTME although the clinicopathological features were not superior to LaTME in this study. Currently, with the lack of evidence on benefits of TaTME, further evaluation of TaTME requires large randomized control trials to be conducted.

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.

Comparison of Short-Term Clinical and Pathological Outcomes after Transanal versus Laparoscopic Total Mesorectal Excision for Low Anterior Rectal Resection Due to Rectal Cancer: A Systematic Review with Meta-Analysis

Background: Transanal total mesorectal excision (TaTME) is a new technique that is designed to overcome the limits of the open and laparoscopic approach for rectal resections. Objective: This study is designed to compare TaTME with standard laparoscopic TME (LaTME). Methods: We searched Medline, Embase, and Scopus databases covering a up to October 2018. Inclusion criteria for study enrolment: (1) study comparing laparoscopic resection of rectal cancer vs. TaTME for rectal malignancy, (2) reporting of overall morbidity, operative time, or major complications. Results: Eleven non-randomized studies were eligible with a total of 778 patients. We found statistical significant differences in regard to major complications in favour of TaTME (RR = 0.55; 95% CI 0.31–0.97; p = 0.04). We did not found significant differences regarding overall complications intraoperative adverse effects, operative time, anastomotic leakage, intra-abdominal abscess occurrence, Surgical Site Infection, reoperations, Length of stay, completeness of mesorectal excision, R0 resection rate, number of harvested lymph nodes, circumferential resection margin, and distal resection margin. Conclusions: This meta-analysis shows benefits of TaTME technique regarding major postoperative complications. Regarding clinicopathological features transanal approach is not superior to LaTME. Currently, the quality of the evidence on benefits of TaTME is low due to lack of randomized controlled trials, which needs to be taken into consideration in further evaluation of the technique. Further evaluation of TaTME require conducting large randomized control trials.