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

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.

Comparing perioperative and oncological outcomes of transanal and laparoscopic total mesorectal excision for rectal cancer: a meta-analysis of randomized controlled trials and prospective studies

INTRODUCTION

Meta-analysis of the results of transanal total mesorectal excision (taTME) and laparoscopic TME (laTME) regarding perioperative and oncological outcomes have been conducted. Due to the lack of high-quality randomized controlled trials (RCTs) and prospective studies in the included literature, the conclusions are unreliable. This study included RCTs and prospective studies for analysis to obtain more reliable conclusions.

MATERIALS AND METHODS

Systematic searches of the PubMed, Embase, and Cochrane Library databases were conducted up to June 2023. To assess the quality, the Cochrane quality assessment tool and the Newcastle-Ottawa Scale were employed. The perioperative and oncological outcomes were then analyzed. The I2 statistic was used to evaluate statistical heterogeneity and sensitivity analyses was conducted.

RESULTS

A total of 22 studies, comprising 5056 patients, were included in the analysis, of which 6 were RCTs and 16 were prospective studies. The conversion rate in the taTME group was significantly lower than that in the laTME group (OR 0.14, 95% CI 0.09 to 0.22, P < 0.01), and the circumferential resection margin (CRM) was longer (MD 0.99 mm, 95% CI 0.66 to 1.32 mm, P < 0.01), with a lower rate of positive CRM involvement (OR 0.68, 95% CI 0.47 to 0.97, P = 0.03). No statistically significant differences were found in terms of the operation time, intraoperative blood loss, complications, anastomotic leakage, uroschesis, obstruction, secondary operation, hospital stay, urethral injury, readmission, mortality rate within 30 days, mesorectal resection quality, number of harvested lymph nodes, distal resection margin (DRM), positive DRM, local recurrence, and distance recurrence (P > 0.05).

CONCLUSION

According to the findings of this meta-analysis, which is based on RCTs and prospective studies, taTME appears to have an advantage over laTME in terms of conversion rate and CRM involvement.

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.

Advances in pelvic imaging parameters predicting surgical difficulty in rectal cancer

Due to the fixed bony structure of the pelvis, the pelvic operation space is limited, complicating the surgical operation of rectal cancer, especially middle and low rectal cancer. The closer the tumor is to the anal verge, the smaller the operative field and operating space, the longer the operative time, and the greater the incidence of intraoperative side injuries and postoperative complications. To date, there is still no clear definition of a difficult pelvis that affects the surgical operation of rectal cancer. Few related research reports exist in the literature, and views on this aspect are not the same between countries. Therefore, it is particularly important to predict the difficulty of rectal cancer surgery in a certain way before surgery and to select the surgical method most suitable for each case during the treatment of rectal cancer.

Intraoperative holographic image-guided surgery in a transanal approach for rectal cancer

PURPOSE

Urethral injury is one of the most important complications in transanal total mesorectal excision (TaTME) in male patients with rectal cancer. The purpose of this study was to investigate holographic image-guided surgery in TaTME.

METHODS

Polygon (stereolithography) files were created and exported from SYNAPSE VINCENT, and then uploaded into the Holoeyes MD system (Holoeyes Inc., Tokyo, Japan). After uploading the data, the three-dimensional image was automatically converted into a case-specific hologram. The hologram was then installed into the head mount display, HoloLens (Microsoft Corporation, Redmond, WA). The surgeons and assistants wore the HoloLens when they performed TaTME.

RESULTS

In a Wi-Fi-enabled operating room, each surgeon, wearing a HoloLens, shared the same hologram and succeeded in adjusting the hologram by making simple hand gestures from their respective angles. The hologram contributed to better comprehension of the positional relationships between the urethra and the surrounding pelvic organs during surgery. All surgeons were able to properly determine the dissection line.

CONCLUSIONS

This first experience suggests that intraoperative holograms contributed to reducing the risk of urethral injury and understanding transanal anatomy. Intraoperative holograms have the potential to become a new next-generation surgical support tool for use in spatial awareness and the sharing of information between surgeons.

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.

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.

Transanal versus laparoscopic total mesorectal excision: a comparative study of long-term oncological outcomes

BACKGROUND

Transanal total mesorectal excision (TaTME) is the most recent approach developed to improve pelvic dissection in surgery for mid and low rectal tumors. There are still inconsistencies regarding the technique's oncological results. The aim of this study was to analyze clinical and oncological outcomes of the learning curve of TaTME in comparison to laparoscopic TME (lapTME).

METHODS

Rectal cancer patients who had TaTME and lapTME in two Portuguese colorectal units between March 2016 and December 2018 were eligible. Primary endpoints were 5-year overall survival, disease-free survival, and local recurrence. Secondary endpoints were clinical and pathological outcomes.

RESULTS

Forty-four patients underwent TaTME (29 men) and 39 lapTME (27 men) with a median age of 69 and 66 (p = 0.093), respectively. No differences were observed concerning baseline characteristics, emphasizing their comparability. In the TaTME group, there were more hand-sewn anastomosis (0 lapTME versus 7 TaTME, p = 0.018) with significantly less distance to the dentate line (40 mm lapTME versus 20 mm TaTME, p = 0.005) and significantly more loop ileostomies performed (28 lapTME versus 41 TaTME, p = 0.001). There were no differences in post-operative mortality, morbidity, readmissions, and stoma closure. Groups were similar in relation to specimen quality, margins, and resectability; however, TaTME had a significantly higher node yield (14 lapTME versus 20 TaTME, p = 0.002). Finally, no disparities were noted in oncological outcomes, namely local and distant recurrence, 5-year overall survival, and disease-free survival.

CONCLUSIONS

Even with the disadvantage of the learning curve of a new technique, TaTME appears to be comparable to lapTME, with similar long-term oncological outcomes. It has, however, a demanding learning curve, significant risk for morbidity and should be used only for selected patients.

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.

A Transabdominal Robotic Purse-String Suture Technique for Transanal Total Mesorectal Excision

Introduction: Transanal total mesorectal excision (TaTME) is a novel technique that overcomes the problem of access to the deep pelvis during radical surgery for mid-rectal and lower rectal cancer. Although TaTME has several important steps, the creation of the distal purse-string suture following TaTME plays an important role in ensuring the integrity of the colorectal anastomosis. However, this procedure represents a major technical challenge for the surgeon. Robot-assisted surgery may make this suturing procedure easier than laparoscopic surgery because it permits intuitive wrist movements and a three-dimensional view. The aim of the present study was to investigate the usefulness of transabdominal robotic purse-string suture during anastomosis in TaTME. Methods: Twenty-seven patients, who underwent anastomosis using a single stapling technique (SST) during the TaTME of mid-rectal or lower rectal cancer, were enrolled in the study. The patients were allocated to two groups: 11 patients underwent transabdominal robotic purse-string suturing (the Robot group) and 16 patients underwent transanal purse-string suturing (the Transanal group). The characteristics and short-term surgical outcomes of the participants were compared between the two groups. Results: The Robot group tended to have a shorter purse-string suturing time (541 ± 206 seconds versus 729 ± 310 seconds; P = .07). Regarding the shape of the "donut" after SST anastomosis, in the Transanal group, 5 of the 16 participants had incomplete donuts with muscular defects and required additional suturing, whereas in the Robot group, all the participants had complete donuts (P = .04). Conclusions: Transabdominal robotic purse-string suturing may facilitate the suturing procedure and contribute to reliable anastomosis.

Controversies and consensus in transanal total mesorectal excision (taTME): Is it a valid choice for rectal cancer?

Transanal total mesorectal excision (taTME) is a novel approach to radical surgery for low rectal cancer. taTME is associated with the benefits of a higher rate of free distal resection margins (DRM) under direct visualization, better visualization of the mesorectal plane, and the feasibility of overcoming the restriction of the distal pelvis. Thus, it is increasingly used globally. In this review, we investigated whether taTME yields better short- and long-term outcomes than laparoscopic TME.

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.

What is the advantage of rectal amputation with an initial perineal approach for primary anorectal carcinoma?

Background

Rectal amputation (RA) remains an important surgical procedure for salvage despite advances in sphincter-preserving resection, including intersphincteric resection. The aim of this study was to compare short- and long-term outcomes of RA with an initial perineal approach to those of RA with an initial abdominal approach (conventional abdominoperineal resection (APR)) for primary anorectal cancer.

Methods

We retrospectively analyzed the short- and long-term outcomes of 48 patients who underwent RA with an initial perineal approach (perineal group) and 21 patients who underwent RA with an initial abdominal approach (conventional group).

Results

For the perineal group, the operation time was shorter than that for the conventional group (313 vs. 388 min, p = 0.027). The postoperative complication rate was similar between the two groups (43.8 vs. 47.6%, p = 0.766). Perineal wound complications (PWCs) were significantly fewer in the perineal group than in the conventional group (22.9 vs. 57.1%, p = 0.006). All 69 patients underwent complete TME, but positive CRM was significantly higher in the conventional group than in the perineal group (0 vs. 19.0%, p = 0.011). There were no significant differences in the recurrence (43.8 vs. 47.6%, p = 0.689), 5-year disease-free survival (63.7% vs. 56.7%, p = 0.665) and 5-year overall survival rates (82.5% vs. 66.2%, p = 0.323) between the two groups.

Conclusion

These data suggest that RA with an initial perineal approach for selective primary anorectal carcinoma is advantageous in minimizing PWCs and positive CRMs. Further investigations on the advantages of this approach are necessary.

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.