Transanal total mesorectal excision: the Slagelse experience 2013-2019

Comparative efficacy analysis of laparoscopic-assisted transanal total mesorectal excision vs laparoscopic transanal mesorectal excision for low-lying rectal cancer

BACKGROUND

With the continuous development of laparoscopic techniques in recent years, laparoscopic total mesorectal excision (LapTME) and laparoscopic-assisted transanal total mesorectal excision (TaTME) have gradually become important surgical techniques for treating low-lying rectal cancer (LRC). However, there is still controversy over the efficacy and safety of these two surgical modalities in LRC treatment.

AIM

To compare the efficacy of LapTME vs TaTME in patients with LRC.

METHODS

Ninety-four patients with LRC who visited and were treated at the Affiliated Hengyang Hospital of Hunan Normal University & Hengyang Central Hospital between December 2022 and March 2024 were selected and divided into the LapTME (n = 44) and TaTME (n = 50) groups. Clinical operation indexes, postoperative recovery indicators, and postoperative complications were recorded. The anal resting pressure (ARP), anal maximum systolic pressure (MSP), and maximum tolerated volume (MTV) of the anal canal were also measured. The intestinal function of patients was evaluated by the Memorial Sloan Kettering Cancer Center (MSKCC) bowel function questionnaire. Serum norepinephrine (NE), adrenaline (AD), and cortisol (Cor) levels were measured. The Quality of Life Questionnaire Core 30 (QLQ-C30) was used for quality of life assessment.

RESULTS

Compared with the LapTME group, the surgery time in the TaTME group was longer; intraoperative blood loss was low; time of anal exhaust, first postoperative ambulation, intestinal recovery, and hospital stay were shorter; and the distal incisal margin and specimen lengths were longer. The TaTME group also showed higher ARP, MSP, and MTV values and higher MSKCC and QLQ-C30 scores than the LapTME group 3 months postoperatively. Cor, AD, and NE levels were lower in the TaTME group than those in the LapTME group during recovery.

CONCLUSION

We demonstrated that TaTME better improved anal function, reduced postoperative stress, and accelerated postoperative recovery and, hence, was safer for patients with LRC.

Margin matters: analyzing the impact of circumferential margin involvement on survival and recurrence after incomplete total mesorectal excision for rectal cancer

BACKGROUND

Incomplete mesorectal excision during rectal cancer surgery often leads to positive circumferential margins, with uncertain prognostic impacts. This study examines whether negative margins can mitigate the poorer prognosis typically associated with incomplete total mesorectal excision (TME) in rectal cancer surgery, thus potentially challenging the prevailing emphasis on complete mesorectal excision.

PATIENTS AND METHODS

A retrospective analysis was conducted on patients who underwent proctectomy for rectal adenocarcinoma with incomplete TME at a single center from 2010 to 2022. Patients were stratified by margin status as determined by pathologic analysis into three groups: involved, not involved with closest margin distance ≤ 2 mm, and not involved with closest margin distance > 2 mm. Outcomes included recurrence and survival. Effects of neoadjuvant therapy protocols on margin status were also assessed.

RESULTS

From 2010 to 2022, 7941 patients underwent proctectomy for rectal cancer, with 236 (3%) having incomplete TME. The median age of these patients was 64 years, and 63% were male. Overall, margin involvement was observed in 54 (23%) patients. The median tumor size was 3.05 cm (interquartile range (IQR): 2-6) for the whole group. Involved margins (23.2%) had reduced overall survival (60.5 months versus 87.3 months, p < 0.001), increased local recurrence (20.4% versus 9.4%, p = 0.024), and lower disease-free survival (45.2 versus 58.9 months, p = 0.006) versus uninvolved margins. Margin involvement was prognostic for decreased survival even after adjusting for confounders (p < 0.05). Among uninvolved margins, distance (> 2 mm versus ≤ 2 mm) did not affect outcomes. Total neoadjuvant therapy (versus standard chemoradiation) was associated with lower involved margins (p = 0.007).

CONCLUSIONS

Positive margins retain negative prognostic impact with incomplete TME. Optimization of surgical resection remains vital. Total neoadjuvant therapy was associated with a lower rate of margin involvement.

Oncologic outcomes following transanal total mesorectal excision: the United States experience

AIM

The benefits and short-term outcomes of transanal total mesorectal excision (taTME) for rectal cancer have been demonstrated previously, but questions remain regarding the oncologic outcomes following this challenging procedure. The purpose of this study was to analyze the oncologic outcomes following taTME at high-volume centers in the USA.

METHODS

This was a multicenter, retrospective observational study of 8 tertiary care centers. All consecutive taTME cases for primary rectal cancer performed between 2011 and 2020 were included. Clinical, histopathologic, and oncologic data were analyzed. Primary endpoints were rate of local recurrence, distal recurrence, 3-year disease recurrence, and 3-year overall survival. Secondary endpoints included perioperative complications and TME specimen quality.

RESULTS

A total of 391 patients were included in the study. The median age was 57 years (IQR: 49, 66), 68% of patients were male, and the median BMI was 27.4 (IQR: 24.1, 31.0). TME specimen was complete or near complete in 94.5% of cases and the rates of positive circumferential radial margin and distal resection margin were 2.0% and 0.3%, respectively. Median follow-up time was 30.7 months as calculated using reverse-KM estimator (CI 28.1-33.8) and there were 9 cases (2.5%) of local recurrence not accounting for competing risk. The 3-year estimated rate of disease recurrence was 19% (CI 15-25%) and the 3-year estimated overall survival was 90% (CI 87-94%).

CONCLUSION

This large multicenter study confirms the oncologic safety and perioperative benefits of taTME for rectal cancer when performed by experienced surgeons at experienced referral centers.

A systematic review and meta-analysis of oncological outcomes with transanal total mesorectal excision for rectal cancer

AIM

Transanal total mesorectal (taTME) excision is a method used to assist in the radical removal of the rectum. By adopting the concept of natural orifice surgery, it offers potential benefits over conventional techniques. Early enthusiasm for this strategy led to its rapid and widespread adoption. The imposing of a local moratorium was precipitated by the discovery in Norway of an uncommon multifocal pattern of locoregional recurrence. The aim of this systematic review and meta-analysis was to determine the incidence of local recurrence after taTME for rectal cancer.

METHOD

Conforming to the Cochrane Handbook for Systematic Reviews of Interventions and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines checklist, a systematic review and meta-analysis was conducted. This included case series and comparative studies between taTME and preferentially laparoscopic procedures published between 2010 and 2021.

RESULTS

There were a total of 1175 studies retrieved. After removal and screening for quality and relevance, the final analysis contained 40 studies. The local recurrence rate following taTME was 3.4% (95% CI 2.9%-3.9%, I2 = 0%) in 4987 patients with follow-up durations ranging from 0.7 to 5.5 years. Compared with laparoscopic TME, local recurrence was not statistically different for the taTME group (p = 0.076); however, it was less probable (OR = 0.51, 95% CI 0.24-1.09, I2 = 0%). Systemic recurrence and circumferential resection margin status were secondary outcomes; however, the differences were not statistically significant.

CONCLUSION

Our data suggest that the local recurrence for regular laparoscopic and transanal TME surgeries may be comparable, suggesting that taTME can be performed without influencing locoregional oncological outcomes in patients treated at specialized institutions and who have been cautiously selected.

The role of transanal compared to laparoscopic total mesorectal excision (taTME vs. lapTME) for the treatment of mid-low rectal cancer in obese patients: outcomes of a multicenter propensity-matched analysis

To compare the rate of sphincter-saving interventions between transanal and laparoscopic Total Mesorectal Excision in this particular group of patients. A multicentre observational study was conducted using a prospective database, including patients diagnosed with rectal cancer below the peritoneal reflection and BMI ≥ 30 kg/m2, who underwent minimally invasive elective surgery over a 5-year period. Exclusion criteria were (1) sphincter and/or puborectalis invasion; (2) multi-visceral resections; (3) palliative surgeries. The study population was divided into two groups according to the intervention: transanal or laparoscopic total mesorectal excision. The primary outcome was the rate of sphincter-saving surgery. Secondary outcomes included conversion, postoperative complications, quality of the specimen, and survival. A total of 93 patients were included; 40 (43%) transanal total mesorectal excision were compared to 53 (57%) laparoscopic. In addition, 35 cases of transanal approach were case-matched with an equal number of laparoscopic approaches, based on gender, tumor's height, and neoadjuvant therapy. In both groups, 43% of the patients had low rectal cancer; however, the rate of sphincter-saving surgery was significantly higher in the transanal group (97% vs. 71%, p = 0.003). There were no conversions to open surgery in the transanal group, compared to 2 cases in the laparoscopic group (6%) (p = 0.246). The percentage of major complications was similar, including the rate of anastomotic leakage (10% transanal vs. 19% laparoscopic, p = 0.835). In our experience, higher percentages of sphincter-saving procedures and lower conversion rates are potential benefits of using the transanal approach in a complex surgical setting population of obese patients with mid-low rectal tumors when compared to laparoscopic.

Multicenter phase II trial of transanal total mesorectal excision for rectal cancer: preliminary results

BACKGROUND

Transanal TME (taTME) combines abdominal and transanal dissection to facilitate sphincter preservation in patients with low rectal tumors. Few phase II/III trials report long-term oncologic and functional results. We report early results from a North American prospective multicenter phase II trial of taTME (NCT03144765).

METHODS

100 patients with stage I-III rectal adenocarcinoma located ≤ 10 cm from the anal verge (AV) were enrolled across 11 centers. Primary and secondary endpoints were TME quality, pathologic outcomes, 30-day and 90-day outcomes, and stoma closure rate. Univariable regression analysis was performed to assess risk factors for incomplete TME and anastomotic complications.

RESULTS

Between September 2017 and April 2022, 70 males and 30 females with median age of 58 (IQR 49-62) years and BMI 27.8 (IQR 23.9-31.8) kg/m2 underwent 2-team taTME for tumors located a median 5.8 (IQR 4.5-7.0) cm from the AV. Neoadjuvant radiotherapy was completed in 69%. Intersphincteric resection was performed in 36% and all patients were diverted. Intraoperative complications occurred in 8% including 3 organ injuries, 2 abdominal and 1 transanal conversion. The 30-day and 90-day morbidity rates were 49% (Clavien-Dindo (CD) ≥ 3 in 28.6%) and 56% (CD ≥ 3 in 30.4% including 1 mortality), respectively. Anastomotic complications were reported in 18% including 10% diagnosed within 30 days. Higher anastomotic risk was noted among males (p = 0.05). At a median follow-up of 5 (IQR 3.1-7.4) months, 98% of stomas were closed. TME grade was complete or near complete in 90%, with positive margins in 2 cases (3%). Risk factors for incomplete TME were ASA ≥ 3 (p = 0.01), increased time between NRT and surgery (p = 0.03), and higher operative blood loss (p = 0.003).

CONCLUSION

When performed at expert centers, 2-team taTME in patients with low rectal tumors is safe with low conversion rates and high stoma closure rate. Mid-term results will further evaluate oncologic and functional outcomes.

Discordance in Total Mesorectal Excision Specimen Grading in a Prospective Phase 2 Multicenter Rectal Cancer Trial: Are We Overestimating the Quality of Our Resections?

OBJECTIVES

To report the results of a rigorous quality control (QC) process in the grading of total mesorectal excision (TME) specimens during a multicenter prospective phase 2 trial of transanal TME.

BACKGROUND

Grading of TME specimens is based on the macroscopic assessment of the mesorectum and standardized through synoptic pathology reporting. TME grade is a strong predictor of outcomes with incomplete (IC) TME associated with increased rates of local recurrence relative to complete or near complete (NC) TME. Although TME grade serves as an endpoint in most rectal cancer trials, in protocols incorporating centralized review of TME specimens for quality assurance, discordance in grading and the management thereof has not been previously described.

METHODS

A phase 2 prospective transanal TME trial was conducted from 2017 to 2022 across 11 North American centers with TME quality as the primary study endpoint. QC measures included (1) training of site pathologists in TME protocols, (2) blinded grading of de-identified TME specimen photographs by central pathologists, and (3) reconciliation of major discordance before trial reporting. Cohen Kappa statistic was used to assess agreement in grading.

RESULTS

Overall agreement in grading of 100 TME specimens between site and central reviewer was rated as fair, (κ = 0.35; 95% CI: 0.10-0.61; P < 0.0001). Concordance was noted in 54%, with minor and major discordance in 32% and 14% of cases, respectively. Upon reconciliation, 13/14 (93%) major discordances were resolved. Pre versus postreconciliation rates of complete or NC and IC TME are 77%/16% and 7% versus 69%/21% and 10%. Reconciliation resulted in a major upgrade (IC-NC; N = 1) or major downgrade (NC/C-IC, N = 4) in 5 cases overall (5%).

CONCLUSIONS

A 14% rate of major discordance was observed in TME grading between the site and central reviewers. The resolution resulted in a major change in final TME grade in 5% of cases, which suggests that reported rates or TME completeness are likely overestimated in trials. QC through a central review of TME photographs and reconciliation of major discordances is strongly recommended.

Transanal Total Mesorectal Excision for Rectal Cancer

Transanal total mesorectal excision (taTME) is a technique where rectal dissection is begun transanally in a "bottom-up" fashion. This technique facilitates dissection of the most distal part of the rectum and allows the establishment of the distal margin for rectal cancer. TaTME has proven its utility in facilitating low rectal dissection with significantly lower conversion rates and acceptable perioperative, oncological, and functional outcomes. However, taTME remains a challenging technique to learn and adopt. This article describes the technique, indications, and outcomes of taTME in rectal cancer during the last decade.

Recurrence following transanal total mesorectal excision for rectal cancer: a monocentric retrospective series of technically difficult cases

PURPOSE

Transanal total mesorectal excision (TaTME) has been proposed to overcome surgical difficulties encountered during rectal resection, especially for patients having high body mass index or low rectal cancer. The aim of this study was to evaluate oncologic outcomes following TaTME.

METHODS

This retrospective study included all consecutive patients with rectal cancer who had a TaTME from 2013 to 2019. The main outcome was the incidence of locoregional recurrence by the end of the follow-up period.

RESULTS

Among a total of 81 patients, 96.3% were male, and their mean age was 63±9 years. The mean body mass index was 30.3±5.7 kg/m2, and the median distance from tumor to anal verge was 5.0 cm (interquartile range [IQR], 4.0-6.0 cm). Most patients had a low anterior resection performed (n=80, 98.8%) with a diverting ileostomy (n=64, 79.0%). Distal and circumferential resection margins were positive in 2.5% and 6.2% of patients, respectively. Total mesorectal excision was complete or near complete in 95.1% of patients. A successful resection was achieved in 72 patients (88.9%). After a median follow-up of 27.5 months (IQR, 16.7-48.1 months), 4 patients (4.9%) experienced locoregional recurrence. Anastomotic leaks were observed in 21 patients (25.9%). At the end of the follow-up, 69 patients (85.2%) were stoma-free.

CONCLUSION

TaTME was associated with acceptable oncological outcomes, including low locoregional recurrence rates in selected patients with low rectal cancer. Although associated with a high incidence of postoperative morbidities, the use of TaTME enabled a high rate of successful sphincter-saving procedures in selected patients who posed a technical challenge.

Simple transanal total mesorectal resection versus laparoscopic transabdominal total mesorectal resection for the treatment of low rectal cancer: a single-center retrospective case-control study

Aim

To evaluate the efficacy and safety of simple TaTNE in the treatment of low rectal cancer compared with laparoscopic transabdominal TME.

Methods

We collected patients with low rectal cancer admitted to our hospital between January 2019 and November 2021 who received simple TaTME or laparoscopic transabdominal TME. The main outcome was the integrity of the TME specimen. Secondary outcomes were the number of lymph nodes dissected, intraoperative blood loss, operative time, surgical conversion rate, Specimen resection length, circumferential margin (CRM), and distal resection margin (DRM), complication rate. In addition, the Wexner score and LARS score of fecal incontinence were performed in postoperative follow-up.

Results

Pathological tissues were successfully resected in all patients. all circumferential margins of the specimen were negative. Specimen resection length was not statistically significant (9.94 ± 2.85 vs. 8.90 ± 2.49, P > 0.05). The incidence of postoperative complications in group A (n = 0) was significantly lower than that in group B (n = 3) (P > 0.05). There was no significant difference in operation time between group A and group B (296 ± 60.36 vs. 305 ± 58.28, P > 0.05). Among the patients with follow-up time less than 1 year, there was no significant difference in Wexner score and LARS score between group A and group B (P > 0.05). However, in patients who were followed up for more than 1 year, the Wexner score in group A (9.25 ± 2.73) was significantly lower than that in group B (17.36 ± 10.95) and was statistically significant (P < 0.05).

Conclusion

For radical resection of low rectal cancer, Simple TaTME resection may be as safe and effective as laparoscopic transabdominal TME, and the long-term prognosis may be better.

Morbidity, Mortality, and Pathologic Outcomes of Transanal Versus Laparoscopic Total Mesorectal Excision for Rectal Cancer Short-term Outcomes From a Multicenter Randomized Controlled Trial

OBJECTIVE

To determine the morbidity, mortality, and pathologic outcomes of transanal total mesorectal resection (taTME) versus laparoscopic total mesorectal excision (laTME) among patients with rectal cancer with clinical stage I to III rectal cancer below the peritoneal reflection.

BACKGROUND

Studies with sufficient numbers of patients allowing clinical acceptance of taTME for rectal cancer are lacking. Thus, we launched a randomized clinical trial to compare the safety and efficacy of taTME versus laTME.

METHODS

A randomized, open-label, phase 3, noninferiority trial was performed at 16 different hospitals in 10 Chinese provinces. The primary endpoints were 3-year disease-free survival and 5-year overall survival. The morbidity and mortality within 30 days after surgery, and pathologic outcomes were compared based on a modified intention-to-treat principle; this analysis was preplanned.

RESULTS

Between April 13, 2016, and June 1, 2021, 1115 patients were randomized 1:1 to receive taTME or laTME. After exclusion of 26 cases, modified intention-to-treat set of taTME versus laTME groups included 544 versus 545 patients. There were no significant differences between taTME and laTME groups in intraoperative complications [26 (4.8%) vs 33 (6.1%); difference, -1.3%; 95% confidence interval (CI), -4.2% to 1.7%; P =0.42], postoperative morbidity [73 (13.4%) vs 66 (12.1%); difference, 1.2%; 95% CI, -2.8% to 5.2%; P =0.53), or mortality [1 (0.2%) vs 1 (0.2%)]. Successful resection occurred in 538 (98.9%) versus 538 (98.7%) patients in taTME versus laTME groups (difference, 0.2%; 95% CI, -1.9% to 2.2%; P >0.99).

CONCLUSIONS

Experienced surgeons can safely perform taTME in selected patients with rectal cancer.

The taTME learning curve for mid-low rectal cancer: a single-center experience in China

Purpose

As transanal total mesorectal excision (taTME) is performed worldwide, the optimization of existing training and guidance programs to enhance new taTME learners’ competence in performing this procedure is warranted. This study aimed to evaluate the taTME learning curve in patients with mid-low rectal cancer.

Methods

Patients who underwent taTME for mid-low rectal cancer between October 2015 and August 2021 at a single center were included. A cumulative sum (CUSUM) learning curve analysis was performed with the total operation time as the study outcome. The learning curve was analyzed using risk-adjusted CUSUM analysis, with postoperative complications and anastomotic leakage (AL) as outcomes.

Results

In total, 104 consecutive patients were included in this study. The CUSUM learning curve for total operative time started declining after 42 cases (309.1 ± 84.4 vs. 220.2 ± 46.4, P < 0.001). The risk-adjusted CUSUM (RA-CUSUM) learning curve for postoperative complications fluctuated in cases 44–75 and declined significantly after case 75. The RA-CUSUM learning curve for AL declined after 68 cases.

Conclusions

taTME had learning curves of 42, 75, and 68 cases for total operative time, postoperative complications, and AL, respectively. A surgeon may require 42 and 75 cases to achieve “proficiency” and “mastery” in taTME procedures, respectively.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-022-02763-3.

Three-year outcomes of transanal total mesorectal excision versus standard laparoscopic total mesorectal excision for mid and low rectal cancer

INTRODUCTION

Since transanal total mesorectal excision (taTME) was introduced, it has become an important topic in rectal cancer treatment. Many previous studies reported positive relevant short-term results, histopathological results, and associated complications. Recently, concerns regarding the oncological safety of taTME have been raised due to reports showing high local recurrences (LR) rates. Therefore, this study aimed to compare the 3-year outcomes between taTME and laparoscopic total mesorectal excision (laTME) for mid-low rectal cancer.

METHODS

A total of 104 patients who underwent taTME were matched with 208 patients treated by laTME. The primary endpoint was 3-year LR rate; secondary endpoints in this matched-cohort study included the perioperative outcomes and histopathological outcomes.

RESULTS

taTME was associated with lower permanent ostomy rate (1% vs 13.5%) and lower conversion rate (0% vs 3.4%) compared to laTME. A similar quality of resected specimens was detected for each group. In both groups, the local recurrence rate was 3.8%. Within 3 years after surgery, the disease-free survival (DFS) rates were 78.8% in the taTME group and 76.9% in the laTME group (P = 0.640), while the overall survival (OS) rates were 93.3% in the taTME group and 89.9% in the laTME group (P = 0.327).

CONCLUSION

No significant differences regarding 3-year local recurrence rate (3.8%) were observed in the taTME group compared to laTME group.

Structured training curriculums for transanal total mesorectal excision in China: refinement is needed

BACKGROUND

Transanal total mesorectal excision (TaTME) is an alternative for mid-low rectal cancer. In China, this procedure has been performed in high-volume centers with structured training curriculums. The efficacy of the TaTME structured training curriculums in China is still unclear. This multicenter study aimed to explore the effectiveness of the structured training curriculums in China.

METHODS

Seven high-volume centers in China participated in this study. The first 25 patients who underwent TaTME in each center were enrolled. In the cohort, patients were divided into 3 groups. The first 5 procedures (group 1) were performed under proctoring according to the requirement of structured training curriculums. The latter 20 cases without proctoring were split into 2 groups (10 cases in each group, groups 2 and 3) according to the order of operation date. The baseline characteristics, perioperative complications, and pathological outcomes were compared between groups 1 and 2, as well as between groups 2 and 3.

RESULTS

Symptomatic anastomotic leakage (AL) occurred in 18.6% of the patients in group 2 compared with 5.7% in group 1 (P1=0.08) and 5.0% in group 3 (P2=0.04). Seven (11.3%) patients in group 2 developed defecation disorders whereas no patients had this complication in group 3 (P2=0.02). Compared with group 2, the operative time was shorter (235 vs. 223 min, P2=0.40), while the rates of intraoperative complications (15.7% vs. 5.7%, P2=0.10), postoperative complications (31.3% vs. 25.7%, P2=0.06), AL (20.0% vs. 8.6%, P2=0.04), and positive distal resection margin (DRM) (7.5% vs. 2.9%, P2=0.27) were lower in group 3.

CONCLUSIONS

The effect of the structured training curriculums was acceptable but needed further improvement. The prevalence of anastomosis-related complications and the quality control of specimens are still not optimal, and measures for refinement (for example, more cases under proctoring) are needed in the curriculums.

Limitations and Concerns with Transanal Total Mesorectal Excision for Rectal Cancer

Transanal total mesorectal excision (TaTME) was developed to overcome the technical challenges of a minimally invasive (ultra-) low anterior resection. This new technique has recently come under careful scrutiny as technical pitfalls were reported, in specific relation to the transanal approach. Patients are at risk for urologic lesions. Moreover, carbon dioxide embolism is a rare but potentially life-threatening complication. The benefit of TaTME from an oncological point of view has neither been clarified. Hypothetically, better visualization of the lower rectum could lead to better dissection and total mesorectal excision (TME) specimens, resulting in better oncologic results. Up until now, retrospective multicenter reports seem to show that short-term oncologic results are not inferior after TaTME as compared with after laparoscopic TME. Alarming reports have however been published from Norway suggesting a high incidence and particular multifocal pattern of early local recurrence. In this article, a balanced overview is given of the most important technical pitfalls and oncological concerns arising with this new procedure.

Transanal Total Mesorectal Excision Versus Anterior Total Mesorectal Excision for Rectal Cancer: A Propensity Score Matched, Population-Based Study in Catalonia, Spain

BACKGROUND

The clinical value of transanal total mesorectal excision is debated.

OBJECTIVE

This study aimed to compare short- and medium-term effects of transanal versus anterior total mesorectal excision for rectal cancer.

DESIGN

This was a multicenter retrospective cohort study.

SETTING

The study included all Catalonian public hospitals.

PATIENTS

All patients receiving transanal or anterior total mesorectal excision (open or laparoscopic) for nonmetastatic primary rectal cancer in 2015 to 2016 were included.

MAIN OUTCOME MEASURES

Data on vital status were collected to March 2019. Between-group differences were minimized by applying propensity score matching to baseline patient characteristics. Competing risk models were used to assess systemic and local recurrence along with death at 2 years, and multivariable Cox regression was used to assess 2-year disease-free survival. Results are expressed with their 95% CIs.

RESULTS

The final subsample was 537 patients receiving total mesorectal excision (transanal approach: n = 145; anterior approach: n = 392). Median follow-up was 39.2 months (interquartile range, 33.0-45.8). Accounting for death as a competing event, there was no association between transanal total mesorectal excision and local recurrence (matched subhazard ratio 1.28, 95% CI 0.55-2.96). There were no statistical differences in the comparative rate of local recurrence (transanal: 1.77 per 100 person-years, 95% CI 0.76-3.34; anterior: 1.37 per 100 person-years, 95% CI 0.8-2.15) or mortality (transanal: 3.98 per 100 person-years, 95% CI 2.36-6.16; anterior: 2.99 per 100 person-years, 95% CI 2.1-4.07). Groups presented similar 2-year cumulative incidence of local recurrence (4.83% versus 3.57%) and disease-free survival (HR, 1.33; 95% CI 0.92-1.92).

LIMITATIONS

We used data only from the public system, the study is retrospective, and data on individual surgeons are not reported.

CONCLUSION

These population-based results support the use of either the transanal, open, or laparoscopic approach for rectal cancer in Catalonia. See Video Abstract at http://links.lww.com/DCR/B744.ESCISIÓN MESORRECTAL TOTAL TRANSANAL VERSUS ESCISIÓN MESORRECTAL TOTAL ANTERIOR PARA EL CÁNCER DE RECTO: UN ESTUDIO POBLACIONAL CON EMPAREJAMIENTO DE PUNTAJE DE PROPENSIÓN EN CATALUÑA, ESPAÑA.

ANTECEDENTES

Se debate el valor clínico de la escisión mesorrectal total transanal.

OBJETIVO

Comparar los efectos a corto y mediano plazo de la escisión mesorrectal total transanal versus anterior para el cáncer de recto.

DISEO

Este fue un estudio de cohorte retrospectivo multicéntrico.

AJUSTE

El estudio incluyó a todos los hospitales públicos de Cataluña.

PACIENTES

Todos los pacientes no metastásicos que recibieron escisión mesorrectal total anterior o transanal (abierta o laparoscópica) por cáncer de recto primario en 2015-16.

PRINCIPALES MEDIDAS DE VALORACION

Los datos sobre el estado vital se recopilaron hasta marzo de 2019. Las diferencias entre los grupos se minimizaron aplicando el emparejamiento de puntajes de propensión a las características iniciales del paciente. Se utilizaron modelos de riesgo competitivo para evaluar la recurrencia sistémica y local junto con la muerte a los dos años, y la regresión de Cox multivariable para evaluar la supervivencia libre de enfermedad a dos años. Los resultados se expresan con sus intervalos de confianza del 95%.

RESULTADOS

La submuestra final fue de 537 pacientes que recibieron escisión mesorrectal total (abordaje transanal: n = 145; abordaje anterior: n = 392). La mediana de seguimiento fue de 39,2 meses (rango intercuartílico 33,0-45,8). Teniendo en cuenta la muerte como un evento competitivo, no hubo asociación entre la escisión mesorrectal total transanal y la recurrencia local (cociente de subriesgo apareado 1,28, 0,55-2,96). No hubo diferencias estadísticas en la tasa comparativa de recurrencia local (transanal: 1,77 por 100 personas-año, 0,76-3,34; anterior: 1,37 por 100 personas-año, 0,8-2,15) o mortalidad (transanal: 3,98 por 100 personas-año, 2,36-6,16; anterior: 2,99 por 100 personas-año, 2,1-4,07). Los grupos presentaron una incidencia acumulada de dos años similar de recidiva local (4,83% frente a 3,57%, respectivamente) y supervivencia libre de enfermedad (índice de riesgo 1,33, 0,92-1,92).

LIMITACIONES

Utilizamos datos solo del sistema público, el estudio es retrospectivo y no se informan datos sobre cirujanos individuales.

CONCLUSIONES

Estos resultados poblacionales apoyan el uso del abordaje transanal, abierto o laparoscópico para el cáncer de recto en Cataluña. Consulte. Video Resumen en http://links.lww.com/DCR/B744. (Traducción- Dr. Francisco M. Abarca-Rendon).

Clinical Status and Future Prospects of Transanal Total Mesorectal Excision

Low rectal cancer has always posed surgical challenges to gastrointestinal surgeons. Transanal total mesorectal excision (taTME) is a novel approach to radical resection for low rectal cancer. Compared with conventional laparoscopic TME (laTME), taTME is relevant to the benefits of better vision of the mesorectal plane, feasibility of operating in a narrow pelvis, and exact definition of distal resection margin, which may lead to a higher possibility of free circumferential resection margin, better quality of TME specimen, and lower conversion rate. Although there are concerns about its long-term oncological outcomes and complex learning curve, taTME is a promising alternative for rectal cancer. In this review, we discuss the application status and prospects of taTME.

Local Recurrence and Disease-Free Survival After Transanal Total Mesorectal Excision: Results From the International TaTME Registry

BACKGROUND

The oncologic safety of transanal total mesorectal excision (TaTME) for rectal cancer has recently been questioned, with high local recurrence (LR) rates reported in Dutch and Norwegian experiences. The objective of this study was to evaluate the oncologic safety of TaTME in a large cohort of patients with primary rectal cancer, primarily in terms of LR, disease-free survival (DFS), and overall survival (OS).

PATIENTS AND METHODS

This was a prospective international registry cohort study, including all patients who underwent TaTME for primary rectal adenocarcinoma from February 2010 through December 2018. The main endpoints were 2-year LR rate, pattern of LR, and independent risk factors for LR. Secondary endpoints included 2-year DFS and OS rates. Kaplan-Meier survival analysis was used to calculate actuarial LR, DFS, and OS rates.

RESULTS

A total of 2,803 patients receiving primary TaTME were included, predominantly men (71%) with a median age of 65 years (interquartile ratio, 57-73 years). After a median follow-up of 24 months (interquartile ratio, 12-38 months), the 2-year LR rate was 4.8% (95% CI, 3.8%-5.8%) with a unifocal LR pattern in 99 of 103 patients (96%). Independent risk factors for LR were male sex, threatened resection margin on baseline MRI, pathologic stage III cancer, and a positive circumferential resection margin on final histopathology. The 2-year DFS and OS rates were 77% (95% CI, 75%-79%) and 92% (95% CI, 91%-93%), respectively.

CONCLUSIONS

This largest TaTME cohort to date supports the oncologic safety of the TaTME technique for rectal cancer in patients treated in units that contributed to an international registry, with an acceptable 2-year LR rate and a predominantly unifocal LR pattern.

The learning curve of transanal total mesorectal excision for rectal cancer is associated with local recurrence: results from a multicentre external audit

AIM

Transanal total mesorectal excision (TaTME) has been suggested as a potential solution for the resection of challenging mid and low rectal cancer. This relatively complex procedure has been implemented in many centres over the last years, despite the absence of long-term safety data. Recently, concern has arisen because of an increase in local recurrence in the implementation phase. The aim of this study was to assess the correlation between accumulated experience and local recurrences.

METHOD

An independent clinical researcher performed an external audit of consecutive series of all TaTME procedures in six centres in the Netherlands. Kaplan-Meier estimated local recurrence rates were calculated and multivariate Cox proportional hazards regression analysis performed to assess risk factors for local recurrence. Primary outcome was the local recurrence rate in the initial implementation (cases 1-10), continued adoption (cases 11-40) and prolonged experience (case 41 onward).

RESULTS

Six hundred and twenty-four consecutive patients underwent TaTME for rectal cancer with a median follow-up of 27 months (range 1-82 months). The estimated 2- and 3-year local recurrence rates were 4.6% and 6.6%, respectively. Cox proportional hazards regression revealed procedural experience to be an independent factor in multivariate analysis next to advanced stage (ycMRF+, pT3-4, pN+) and pelvic sepsis. Corrected analysis projected the 3-year local recurrence rates to be 9.7%, 3.3% and 3.5% for the implementation, continued adoption and prolonged experience cohorts, respectively.

CONCLUSION

This multicentre study shows a high local recurrence rate (12.5%) after implementation of TaTME which lowers to an acceptable rate (3.4%) when experience increases. Therefore, intensified proctoring and further precautions must be implemented to reduce the unacceptably high risk of local recurrence at units starting this technique.

Statistical, Clinical, Methodological Evaluation of Local Recurrence Following Transanal Total Mesorectal Excision for Rectal Cancer: A Systematic Review

BACKGROUND

A recent Norwegian moratorium challenged the status quo of transanal total mesorectal excision for rectal cancer by reporting increased early multifocal local recurrences.

OBJECTIVE

The aim of this systematic review and meta-analysis was to evaluate the local recurrence rates following transanal total mesorectal excision as well as to assess statistical, clinical, and methodological bias in reports published to date.

DATA SOURCES

The PubMed and MEDLINE (via Ovid) databases were systematically searched.

STUDY SELECTION

Descriptive or comparative studies reporting rates of local recurrence at a median follow-up of 6 months (or more) after transanal total mesorectal excision were included.

INTERVENTIONS

Patients underwent transanal total mesorectal excision.

MAIN OUTCOME MEASURES

Local recurrence was any recurrence located in the pelvic surgery site. The untransformed proportion method of 1-arm meta-analysis was utilized. Untransformed percent proportion with 95% confidence interval was reported. Ad hoc meta-regression with the Omnibus test was utilized to assess risk factors for local recurrence. Among-study heterogeneity was evaluated: statistically by I2 and τ2, clinically by summary tables, and methodologically by a 33-item questionnaire.

RESULTS

Twenty-nine studies totaling 2906 patients were included. The pooled rate of local recurrence was 3.4% (2.7%-4.0%) at an average of 20.1 months with low statistical heterogeneity (I2 = 0%). Meta-regression yielded no correlation between complete total mesorectal excision quality (p = 0.855), circumferential resection margin (p = 0.268), distal margin (p = 0.886), and local recurrence rates. Clinical heterogeneity was substantial. Methodological heterogeneity was linked to the excitement of novelty, loss aversion, reactivity to criticism, indication for transanal total mesorectal excision, nonprobability sampling, circular reasoning, misclassification, inadequate follow-up, reporting bias, conflict of interest, and self-licensing.

LIMITATIONS

The studies included had an observational design and limited sample and follow-up.

CONCLUSION

This systematic review found a pooled rate of local recurrence of 3.4% at 20 months. However, given the substantial clinical and methodological heterogeneity across the studies, the evidence for or against transanal total mesorectal excision is inconclusive at this time.

Oncological outcomes and stoma-free survival following TaTME, a prospective cohort study

BACKGROUND

Transanal TME (TaTME) was introduced to improve access to the pelvis in difficult cases (male sex, obesity and mid to low rectal cancers) and reduce the risk of anastomotic leak by avoiding cross stapling. In April 2018 the Norwegian hospital to whom all local; recurrences for rectal cancer are referred reported an unexpected rise in early multifocal local recurrences of 9.5% following TaTME compared with 3.4% following conventional TME leading to a nationwide moratorium on the procedure and ending, in an editorial published on the British Journal of Surgery in August 2020, by saying that other countries should consider the issue in the context of local practices and results. There are limited data concerning oncological outcomes of TaTME compared to conventional TME. The aim of this study was to report perioperative and oncological outcomes for patients with rectal cancer treated with TaTME in a high-volume, experienced UK centre.

METHODS

From January 2015 to January 2020 consecutive patients with histologically confirmed rectal cancer having TaTME at Worcestershire Royal Hospital NHS were prospectively entered into an online international registry. Patients were followed according to local protocol with clinical examination, tumour markers, endoscopy and radiology.

RESULTS

Seventy patients underwent TaTME for rectal cancer. The median distance of the tumour from the anorectal junction was 4 cm (IQR 2-5). The mesorectal margin was involved in 20 (1%) patients, all of whom received neoadjuvant chemoradiotherapy. Overall survival was 94% at a median follow-up of 15 months (IQR 9-31 months). Distant recurrence occurred in 12 (17%) of patients at a median of 14 months (IQR 10-17 months). The 18-month stoma-free survival rate was 66%.

CONCLUSIONS

A local recurrence rate of 5.7% supports the oncological safety of TaTME for rectal cancer.

Association of Transanal Total Mesorectal Excision With Local Recurrence of Rectal Cancer

IMPORTANCE

Proponents of novel transanal total mesorectal excision (TME) suggest the procedure overcomes the technical and oncologic challenges of conventional approaches for treating rectal cancer. Recently, however, there has been controversy regarding the oncologic safety of the procedure.

OBJECTIVE

To assess the association of transanal TME with the incidence of local recurrence (LR) of cancer and the probability of remaining free of LR during follow-up.

DESIGN, SETTING, AND PARTICIPANTS

This multicenter cohort study used data from 8 high-volume rectal cancer academic institutions from across Canada on all consecutive patients with primary rectal cancer treated by transanal TME at the participating centers. The study was conducted between January 2014 and December 2018, and data were analyzed from April 1, 2020, to September 15, 2020.

EXPOSURE

Transanal TME.

MAIN OUTCOMES AND MEASURES

The incidence of LR was reported as a direct measure of quality of resection. The cumulative probability of LR- and systemic recurrence (SR)-free survival at 36 months was estimated. Local recurrence and SR were defined as radiologic or endoscopic evidence of 1 or more new lesions in or outside the pelvis, respectively, documented during surveillance after the removal of the primary tumor.

RESULTS

Of 608 total patients included in the analysis, 423 (69.6%) were male; the median age was 63 years (interquartile range [IQR], 54-70 years). Local recurrence was identified in 22 patients (3.6%) after a median follow-up of 27 months (IQR, 18-38 months). The median time to LR was 13 months (IQR, 9-19 months). Sixteen of the 22 patients with LR (72.7%) were male, 14 (63.6%) received neoadjuvant chemoradiation, and 12 (54.5%) had American Joint Committee on Cancer stage III disease. Of those with LR, 16 (72.7%) had a negative circumferential radial margin and 20 (90.9%) had a negative distal resection margin, 2 (9.1%) experienced conversion to open surgery, and 15 (68.2%) also developed SR. The probability of LR-free survival at 36 months was 96% (95% CI, 94%-98%). According to the Cox proportional hazards regression model, the hazard ratio of LR was estimated to be 4.2 (95% CI, 2.9-6.2) times higher among patients with a positive circumferential radial margin than among those with a negative circumferential radial margin.

CONCLUSIONS AND RELEVANCE

In this cohort study, transanal TME performed by experienced surgeons was associated with an incidence of LR and SR that is in line with the published literature on open and laparoscopic TME, suggesting that transanal TME may be an acceptable approach for management of rectal cancer.

Transanal total mesorectal excision outcomes for advanced rectal cancer in a complex surgical population

BACKGROUND

Total mesorectal excision (TME) is the gold standard for oncologic resection in low and mid rectal cancers. However, abdominal approaches to TME can be hampered by poor visibility, inadequate retraction, and distal margin delineation. Transanal TME (taTME) is a promising hybrid technique that was developed to mitigate the difficulties of operating in the low pelvis and to optimize the circumferential resection and distal margins.

METHODS

The objective of this study was to characterize our experience implementing taTME at our institution in a technically challenging patient population. We performed a retrospective review of consecutive patients who underwent taTMEs between November 2013 and May 2019 for rectal cancer at a tertiary community cancer center. Outcome measures included pathologic grading of TME specimen, post-operative complications, and oncologic outcomes.

RESULTS

Forty-four patients with mid and low rectal cancer underwent low anterior resection via taTME. The most common staging modality was rectal MRI which demonstrated T3 or T4 tumors in 89% of our patients prior to neoadjuvant. Eighty-six percent of patients underwent neoadjuvant chemoradiation. The initial cases were performed sequentially as a single team, but we later transitioned to a synchronous, two-team approach. Ninety-one percent of TME grades were complete or near complete. Only one patient (2.3%) had a positive circumferential margin. Six patients developed anastomotic leaks with an overall anastomotic complication rate of 18.2%. Two patients (4.5%) with primary rectal cancer developed local recurrence, one of which developed multifocal local recurrence.

CONCLUSIONS

Using the taTME approach on selected locally advanced low rectal cancers, especially in technically complex irradiated and obese male patients, has yielded comparably safe and effective outcomes to laparoscopic proctectomy.

Transanal total mesorectal excision for stage II or III rectal cancer: pattern of local recurrence in a tertiary referral center

BACKGROUND

For mid and low rectal cancer, transanal total mesorectal excision (TaTME) has been established as an alternative approach to laparoscopic surgery. However, there are concerns about an unexpected pattern of local recurrence. This study aimed to analyze the pattern of local recurrence for patients treated with TaTME in a tertiary referral center.

METHODS

A retrospective single-center analysis was performed. Since 2011, all patients with rectal cancer undergoing TaTME with curative intent were prospectively included in a standardized database. Patients with tumors within 12 cm, clinical stage II or III were included. The primary endpoint of the study was the overall local recurrence rate, together with a critical analysis of the patterns of local failures.

RESULTS

Two hundred and five patients were included in this analysis. At the time of surgery, patients had a mean age of 67.1 years (SD 12.3), and 66.8% were male. Neoadjuvant therapy was administered in 73.7%. Mesorectal specimen quality was complete or near-complete in 98.5%, while circumferential resection margin was ≤ 1 mm (including T4 tumors) in 11.8%. After a median follow-up of 34.3 months (95% CI 30.1-38.5), 3.4% (n = 7) presented with local recurrent disease. Six out of the seven patients were also diagnosed with hematogenous metastases. Of the seven patients, three presented with at least one of the following risk factors: T4 tumor, N2 disease, incomplete mesorectal specimen, or positive CRM. Local failure was noted posteriorly (n = 3), laterally (n = 2), anteriorly (n = 1), and in the axial compartment (n = 1). Median time to relapse was 31.5 months (10.3-40.9). The median follow-up after local recurrence was 7.9 (95% CI 6.7-9.1) months, with an overall survival of 85.7%.

CONCLUSIONS

TaTME provided satisfactory local recurrence outcomes, and the most common patterns of failure were in the central pelvis.

Initial Experience with the Safe Implementation of Transanal Total Mesorectal Excision (TaTME) as a Standardized Procedure for Low Rectal Cancer

Introduction: The laparoscopic approach for TME is proven to be non-inferior in oncological outcome compared to open surgery. Anatomical limitations in the male and obese pelvis with resulting pathological shortcomings and high conversion rates were stimuli for alternative approaches. The transanal approach for TME (TaTME) was introduced to overcome these limitations. The aim of this study was to evaluate the outcomes of TaTME for mid and low rectal cancer at our center. Methods: TaTME is a hybrid procedure of simultaneously laparoscopic and transanal mesorectal excision. A retrospective analysis of all consecutive TaTME procedures performed at our center for mid and low rectal cancer between December 2014 and January 2020 was conducted. Results: A total of 157 patients underwent TaTME, with 72.6% receiving neoadjuvant chemoradiation. Mean tumor height was 6.1 ± 2.3 cm from the anal verge, 72.6% of patients had undergone neoadjuvant chemoradiotherapy, and 34.2% of patients presented with a threatened CRM upon pretherapeutic MRI. Abdominal conversion rate was 5.7% with no conversion for the transanal dissection. Early anastomotic leakage occurred in 7.0% of the patients. Mesorectum specimen was complete in 87.3%, R1 resection rate was 4.5% (involved distal resection margin) and in 7.6%, the CRM was positive. The three-year local recurrence rate of 58 patients with a follow-up ≥ 36 months was 3.4%. Overall survival was 92.0% after 12 months, and 82.2% after 36 months. Conclusion: TaTME can be performed safely with acceptable long-term oncological outcome. Low rectal cancer can be well addressed by TaTME, which is an appropriate alternative with low conversion, local recurrence, adequate mesorectal quality and CRM positivity rates.

Transanal total mesorectal excision: 3-year oncological outcomes

BACKGROUND

Rectal cancer treatment has evolved with the implementation of new surgical techniques. Transanal total mesorectal excision (TaTME) is the most recent approach developed to facilitate pelvic dissection of mid- and distal rectal tumours. The purpose of this study was to analyse the short- and mid-term oncological outcomes of TaTME.

METHODS

A study was conducted on patients treated with TaTME for rectal cancer at two colorectal units in Portugal between March 2016 and December 2018. Clinical, pathological and oncological data were retrospectively analysed. Primary endpoints were 3-year overall survival, disease-free survival and local recurrence. Secondary endpoints were clinical and pathological outcomes.

RESULTS

Fifty patients (31 males, [62%], median age 66 years [range 40-85 years]) underwent TaTME, 49 (98%) for malignant and 1 (2%) for benign disease. There were no cases of conversion, 49 (98%) patients had complete or near-complete mesorectum, all the resections were R0 with adequate distal and circumferential margins. With a median follow-up of 36 months, there were 2 cases (4%) of local recurrence and 3-year estimated overall survival and disease-free survival were 90% and 79%, respectively.

CONCLUSIONS

TaTME can provide safe mid-term oncological outcomes, similar to what has been published for classic and laparoscopic TME. Our results also show how demanding this novel approach can be and the consequent need for audited data and standardized implementation.

[Transanal total mesorectal excision-Indications, technique and results]

Total mesorectal excision (TME) has become the standard treatment for rectal cancer in the middle and lower third. Meanwhile, many international trials have confirmed the noninferiority of laparoscopic TME compared to the open technique. Nevertheless, in the presence of anatomical limitations, such as narrow, obese, male pelvises as well as large rectal tumors, the adequate resection of the lower third of the rectum according to oncological criteria, is still challenging even for specialized colorectal surgeons. Therefore, the implementation of innovative approaches, such as robotic-assisted and transanal TME (TaTME) should shed light on this anatomically complex region and guarantee an oncological radical resection and the best possible preservation of neural structures. The advantages of this technique have so far only been provided by retrospective cohort studies by large international centers. Therefore, international prospective randomized trials are currently recruiting patients to analyze the surgical and oncological outcome of TaTME compared to conventional techniques. This article describes the TaTME technique per se, the fields of application and the current data situation. Practical recommendations for the safe implementation of this operative procedure are also presented. The TaTME procedure is reserved for highly specialized colorectal centers with a high volume of rectal cancer cases and appropriate expertise in minimally invasive visceral surgery.Die totale mesorektale Exzision (TME) ist der Goldstandard im Kontext der multimodalen Behandlung des Rektumkarzinoms im mittleren und unteren Drittel. Der transanale Zugang ist eine Ergänzung des zunehmend laparoskopischen Vorgehens, welcher gerade bei anatomischen Limitationen bei der onkologisch adäquaten Resektion des distalen Rektums Abhilfe schaffen soll. Die Nichtunterlegenheit in chirurgischen und onkologischen Parametern wird gegenüber konventionellen (laparoskopisch/offen) Operationsmethoden derzeit intensiv beforscht. Eine sichere Implementation dieser herausfordernden Technik ist an ein modulares Trainingskurrikulum gebunden.

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.