Three-year outcome after transanal versus laparoscopic total mesorectal excision in locally advanced rectal cancer: a multicenter comparative analysis

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.

Long-term oncological outcomes of transanal versus laparoscopic total mesorectal excision for mid-low rectal cancer: a retrospective analysis of 2502 patients

BACKGROUND

Transanal total mesorectal resection (taTME) has recently emerged as a promising surgical approach for the treatment of mid-low rectal cancer. However, there is limited evidence on the long-term survival outcomes associated with taTME. This retrospective study aimed to compare the overall survival (OS), disease-free survival (DFS), and cancer-specific survival of taTME and laparoscopic TME (laTME) in patients with mid-low rectal cancer.

MATERIALS AND METHODS

From July 2014 to June 2022, a total of 3627 patients were identified from two prospective cohorts: the laparoscopic rectal surgery cohort and the CNTAES cohort. To balance the baseline characteristics between the taTME and laTME groups, propensity score matching (PSM) was performed.

RESULTS

A total of 2502 patients were included in the study. Prior to PSM, the laTME group comprised 1853 patients, while the taTME group comprised 649 patients. The 5-year OS (82.9% vs. 80.4%, P =0.202) and 5-year DFS (74.4% vs. 72.5%, P =0.167) were comparable between the taTME and laTME groups. After PSM, the taTME group showed no statistically significant difference in the 5-year OS (83.1% vs. 79.2%, P =0.101) and 5-year DFS (74.8% vs. 72.1%, P =0.135) compared to the laTME group. Subgroup analysis further suggested that taTME may potentially reduce the risk of death [hazard ratio 0.652; (95% CI, 0.452-0.939)] and disease recurrence [hazard ratio 0.736; (95% CI, 0.562-0.965)] specifically in patients with low rectal cancer.

CONCLUSION

In this study, taTME demonstrated comparable oncologic safety to laTME in patients with mid-low rectal cancer. Moreover, the results indicate that taTME may confer potential survival benefits for patients with low rectal cancer.

Exfoliate cancer cell analysis in rectal cancer surgery: comparison of laparoscopic and transanal total mesorectal excision, a pilot study

PURPOSE

Minimally invasive surgery (MIS) is currently the standard treatment for rectal cancer. However, its limitations include complications and incomplete total mesorectal resection (TME) due to anatomical features and technical difficulties. Transanal TME (TaTME) has been practiced since 2010 to improve this, but there is a risk of local recurrence and intra-abdominal contamination. We aimed to analyze samples obtained through lavage to compare laparoscopic TME (LapTME) and TaTME.

METHODS

From June 2020 to January 2021, 20 patients with rectal cancer undergoing MIS were consecutively and prospectively recruited. Samples were collected at the start of surgery, immediately after TME, and after irrigation. The samples were analyzed for carcinoembryonic antigen (CEA) and cytokeratin 20 (CK20) through a quantitative real-time polymerase chain reaction. The primary outcome was to compare the detected amounts of CEA and CK20 immediately after TME between the surgical methods.

RESULTS

Among the 20 patients, 13 underwent LapTME and 7 underwent TaTME. Tumor location was lower in TaTME (7.3 cm vs. 4.6 cm, P=0.012), and negative mesorectal fascia (MRF) was more in LapTME (76.9% vs. 28.6%, P=0.044). CEA and CK20 levels were high in 3 patients (42.9%) only in TaTME. There was 1 case of T4 with incomplete purse-string suture and 1 case of positive MRF with dissection failure. All patients were followed up for an average of 32.5 months without local recurrence.

CONCLUSION

CEA and CK20 levels were high only in TaTME and were related to tumor factors or intraoperative events. However, whether the detection amount is clinically related to local recurrence remains unclear.

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.

Oncological monitoring after transanal total mesorectal excision (TaTME) for rectal neoplasia

BACKGROUND

The surgical treatment of choice for rectal neoplasia is total mesorectal excision (TME). The transanal approach enables a better approach in male and obese patients and/or those with a narrow pelvis and in patients with small tumors. Short-term results are comparable with those for laparoscopy or the open approach, but the medium- and long-term oncological data are sparse. The aim of the present study was to evaluate our early experience with transanal TME (TaTME).

METHODS

This was a retrospective study conducted on patients who underwent TaTME at our center between August 2013 and April 2017 with a follow-up ≥ 3 years. Histopathology, complications, mortality, neoplastic recurrence and disease-free survival were analyzed.

RESULTS

One hundred patients (68 men and 32 women,, median age 66.8 years [range 29.6-91.2 years]) were included. There were 67 T3 cases (67%) with 74 N0 cases (74%), the mesorectal quality was graded optimal for 87.6% and only 2 cases of radial margin involvement were detected (2%). The median follow-up period was 47.6 months (range 11.8-78.9 months). Eighteen cases of recurrence were diagnosed, of which 3 (3%) recurred locally with an average disease-free period of 43.1 months. Overall survival was 80% and mortality due to progression of disease was 13%.

CONCLUSIONS

TaTME is a safe surgical procedure with surgical, anatomopathological and oncological results at 3 years (medium-term) comparable with those for the laparoscopic and open approaches. Better monitoring is required with studies of the long-term functional and quality of life outcomes, i.e., at 5 or 10 years.

What Is the Comparative Efficacy of Surgical, Endoscopic, Transanal Resection, and Radiotherapy Modalities in the Treatment of Rectal Cancer?

BACKGROUND

Rectal cancer is a significant healthcare burden, and effective treatment is crucial. This research aims to compare the effectiveness of surgical and endoscopic resection, transanal resection, and radiotherapy.

METHODS

A literature analysis was conducted in order to identify relevant studies, by comparing the different surgical approaches and variables affecting treatment decisions. The findings were analyzed and synthesized to provide a comprehensive overview.

RESULTS

Surgical treatment, particularly TME (total mesorectal excision), proved consistent efficacy in achieving complete tumor resection and improving long-term survival. Endoscopic treatment and transanal resection techniques were promising for early-stage tumors but were associated with higher local recurrence rates. Radiotherapy, especially in combination with chemotherapy, played a crucial role in locally advanced cases, improving local control and reducing recurrence risk. Patient data, tumor characteristics, and healthcare system factors were identified as important factors in treatment modality selection.

CONCLUSION

Surgical treatment, specifically TME, remains the recommended standard approach for rectal cancer, providing excellent oncological outcomes. Endoscopic treatment and transanal resection techniques can be considered for selected early-stage cases, while radiotherapy is beneficial for locally advanced tumors. Treatment decisions should be personalized based on patient and tumor characteristics, considering the available resources and expertise within the healthcare system.

Learning Curve for Transanal Total Mesorectal Excision for Low Rectal Malignancy

BACKGROUND

Although transanal total mesorectal excision (TaTME) is a promising treatment for low rectal cancer, it is considered technically demanding, and the number of cases required to become proficient in TaTME remains unknown. The purpose of this study was to assess the TaTME learning curve based on the total mesorectal excision completion time.

STUDY DESIGN

This retrospective analysis comprised 128 individuals who received TaTME between September 2016 and December 2021. The cumulative sum method was used to generate the learning curve. The duration of the procedure from the beginning to the end of the circumferential rendezvous was used to define the total mesorectal excision completion time.

RESULTS

The learning curve consists of 3 phases: phase I (learning phase: cases 1 to 38), phase II (consolidation phase: cases 39 to 70), and phase III (maturing phase: cases 71 to 128). As the phases varied, both the overall operative time and total mesorectal excision completion time decreased considerably. Through the 3 phases of TaTME, intraoperative adverse events decreased, and in phase III, none occurred. Only 1 instance of local recurrence occurred during phase III, and none occurred during phase I or II.

CONCLUSIONS

After 70 operations, the surgeon could join the mastery phase of TaTME based on the total mesorectal excision completion time. After the mastering phase began, there were no intraoperative negative occurrences. From the beginning, the oncological safety could be guaranteed.

Efficacy of transperineal minimally invasive surgery with laparoscopic abdominoperineal excision for lower rectal cancer

PURPOSE

In abdominoperineal excision (APE), the advantages of the "down-to-up" approach are expected to be more obvious when performed as a two-team approach, including transperineal minimally invasive surgery (TpMIS). We investigated the efficacy of TpMIS with laparoscopic APE for lower rectal cancer.

METHODS

Patients who underwent laparoscopic APE with (n = 20) or without (n = 30) TpMIS between December 2013 and April 2020 were retrospectively reviewed. Patient and tumor characteristics, intraoperative outcome, short-term outcome, and pathological findings were compared. Additional subgroup analyses were performed in technically challenging cases, including male patients, obese patients, and patients with tumors located at the anterior wall.

RESULTS

There was no marked difference in the patient or tumor characteristics or short-term outcomes, including morbidity and mortality between the two groups. Pathological results were comparable, and the circumferential resection margin (CRM) positive rate was 10% in both groups. TpMIS achieved a significant reduction in operative time (p = 0.02). In a subgroup analysis, the amount of blood loss was also smaller in males (p = 0.02) and patients with a high BMI (> 25) (p = 0.005) than in others.

CONCLUSION

Simultaneously performing TpMIS and laparoscopic APE is feasible owing to the favorable complication and CRM-positive rates. In terms of operative time and blood loss, TpMIS is expected to be advantageous in both easy and challenging cases.

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.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00464-022-09090-4.

Neoadjuvant chemotherapy and radiotherapy followed by resection/ablation in stage IV rectal cancer patients with potentially resectable metastases

Background

The optimal treatment of stage IV rectal cancer remains controversial. The purpose of this study was to assess the treatment outcomes and toxicity of neoadjuvant chemotherapy and radiotherapy followed by local treatment of all tumor sites and subsequent adjuvant chemotherapy in stage IV rectal cancer patients with potentially resectable metastases.

Methods

Adult patients diagnosed with locally advanced rectal adenocarcinoma with potentially resectable metastases, who received neoadjuvant chemotherapy and radiotherapy from July 2013 and September 2019 at Sun Yat-sen University cancer center, were included. Completion of the whole treatment schedule, pathological response, treatment-related toxicity and survival were evaluated.

Results

A total of 228 patients were analyzed with a median follow-up of 33 (range 3.3 to 93.4) months. Eventually, 112 (49.1%) patients finished the whole treatment schedule, of which complete response of all tumor sites and pathological downstaging of the rectal tumor were observed in three (2.7%) and 90 (80.4%) patients. The three-year overall survival (OS) and progression-free survival (PFS) of all patients were 56.6% (50.2 to 63.9%) and 38.6% (95% CI 32.5 to 45.8%), respectively. For patients who finished the treatment schedule, 3-year OS (74.4% vs 39.2%, P < 0.001) and 3-year PFS (45.5% vs 30.5%, P = 0.004) were significantly improved compared those who did not finish the treatment. Grade 3–4 chem-radiotherapy treatment toxicities were observed in 51 (22.4%) of all patients and surgical complications occurred in 22 (9.6%) of 142 patients who underwent surgery, respectively.

Conclusions

Neoadjuvant chemotherapy and radiotherapy followed by resection/ablation and subsequent adjuvant chemotherapy offered chances of long-term survival with tolerable toxicities for selected patients with potentially resectable stage IV rectal cancer, and could be considered as an option in clinical practice.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-09089-5.

The role of transanal total mesorectal excision

At inception, transanal total mesorectal excision (TaTME) was hypothesized to be a solution for several problems encountered in pelvic surgery, particularly for distal rectal cancer. The transanal part of the procedure is less hampered by patient related factors such as visceral obesity and a narrow bony pelvis and can thus overcome access and visualization problems encountered with a pure abdominal approach. Clearly, as for any new technique, a learning curve needs to be negotiated, ideally without unacceptable harm to patients. Once in experienced hands, TaTME might overcome challenges found in anatomically challenging rectal cancer patients as well as for other indications. The role of TaTME is not to replace, but rather complement its abdominal counterpart.

Defining the learning curve of transanal total mesorectal excision: a systematic review and meta-analysis

BACKGROUND

Transanal total mesorectal excision (taTME) represents a novel approach to rectal dissection. Although many structured training programs have been developed worldwide to assist surgeons in implementing this new technique, the learning curve (LC) of taTME has yet to be conclusively defined. This is particularly important given the concerns regarding the complication profile and oncological safety of taTME. The aim of this review was to provide an up-to-date systematic review and meta-analysis of the LC for taTME, comparing the difference of outcomes between the LC and after learning curve (ALC) groups.

METHODS

An up-to-date systematic review was performed on the available literature between 2010-2020 on PubMed, EMBASE, Medline and Cochrane Library databases. All studies comparing taTME procedures before and after LC were analysed.

RESULTS

Seven retrospective studies of prospectively collected databases were included, comparing 333 (51.0%) patients in the LC group and 320 (49.0%) patients in the ALC group. There was a significantly reduced number of adverse intra-operative events, anastomotic leaks and improved quality of mesorectal excision in the ALC group.

CONCLUSION

This review shows that there is a significant improvement in clinical outcomes between the LC and ALC groups which supports the need for careful mastery and ongoing technical refinement during the LC in taTME. This procedure should be performed on a subset of carefully selected patients in the hands of experienced and well-trained teams dedicated to ongoing audit.

Locoregional recurrence after transanal total mesorectal excision: an emotional rollercoaster

Transanal total mesorectal excision is a complex technique that should be performed in expert centers.

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.

Verification of data in a nationwide transanal total mesorectal excision registry in China

BACKGROUND AND OBJECTIVES

Transanal total mesorectal excision is a surgical procedure for mid- and low rectal cancer. The Chinese TaTME Registry Collaborative is a nationwide database collecting information on patients who have undergone this procedure.

METHODS

Centers were invited by the registry committee to participate in a three-part data audit project: remote audits for data completeness and deviation values, onsite source verification of data accuracy, and an online survey of the characteristics of data managers.

RESULTS

Twenty-three tertiary centers participated in this project. The median case volume registered by the centers was 51 (interquartile range, 25-89). The overall data completeness for 30 verified variables was 89.1%. Eight centers achieved a high data completeness rate (>95%). The source data of eight centers were verified onsite. The overall accuracy rate was 90.4% (85.3%-97.6% across centers). Postoperative complications, mortality, and proximal/distal resection margin involvement were accurately reported in >95% of cases. The data completeness rate was higher if the data manager was a surgeon/surgical resident (94.2% vs. 84.8%, p = 0.045).

CONCLUSIONS

The completeness and accuracy of the data in the Chinese TaTME Registry Collaborative are acceptable. The quality of the data is highest when entered by colorectal surgeons and residents.