Transanal total mesorectal excision (taTME) for cancer located in the lower rectum: short- and mid-term results

Evaluating Postoperative Prognosis: A Single Surgeon's Experience With Total Mesorectal Excision in Middle and Lower Rectal Cancer Cases in Iraq

INTRODUCTION

Surgical intervention for rectal cancer is widely recognized for its potential to significantly impact quality of life, chiefly due to the high probability of permanent colostomy and the associated postoperative complications.

OBJECTIVE

This study aimed to evaluate the short-term outcomes and morbidity associated with total mesorectal excision for middle and lower rectal cancer within an Iraqi cohort, in a prospective setting.

METHODS

This study prospectively collected and analyzed data from 89 patients who underwent a standardized radical rectal resection, with a follow-up period extending to one month post-surgery.

RESULTS

The mean age of patients was 54.4 ± 12.9 years, with a gender distribution of 46 males and 43 females. A total of 33 patients presented with preoperative comorbidities, which heightened the risk of adverse short-term outcomes by a factor of 7.51. The most prevalent comorbidities were hypertension and diabetes mellitus, affecting 22 and 20 patients, respectively. Patients aged 60 years and above were at a 3.97 times greater risk of developing complications. The overall complication rate was 21.35%, with wound infections (9.0%) and cardiovascular events (3.4%) being the most common. Mortality during the follow-up was 1.1%.

CONCLUSION

The findings indicate that increased age and the presence of comorbidities are significant risk factors for morbidity and mortality post-surgery. Neoadjuvant chemoradiotherapy or radiotherapy was shown to reduce morbidity and mortality rates while improving survival. The morbidity and mortality rates observed in this study concur with existing literature.

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.

Feasibility and safety of robotic surgery for low rectal cancer combined with transanal total mesorectal excision

PURPOSE

Laparoscopic surgery for low rectal cancer is often challenging. Transanal total mesorectal excision (TaTME) and robotic surgery have been introduced to overcome the technical difficulties in laparoscopic surgery and achieve more favorable outcomes. Hybrid robotic surgery, which combines TaTME with the abdominal robotic approach, incorporates the advantages of each of these surgical techniques and might achieve less invasive and safer surgery. This study evaluated the safety and feasibility of hybrid robotic surgery with TaTME (hybrid TaTME).

METHODS

We retrospectively reviewed 162 TaTME cases performed at our department from September 2016 to May 2022. Among them, 92 cases of conventional TaTME and 30 of hybrid TaTME were eligible. We used propensity score matching analysis (PSM) to adjust for patients' characteristics and compared the short-term outcomes of the two treatment groups.

RESULTS

Twenty-seven cases in each group were extracted using PSM. The operation time in hybrid TaTME was comparable to that in conventional TaTME. There was no significant difference in the postoperative hospital stay between the two groups. Other intra- and post-operative outcomes were also comparable between the two groups. Furthermore, no significant differences were observed between the two groups in the curative resection and recurrence rates.

CONCLUSION

Hybrid TaTME for low rectal cancer was as favorable as conventional TaTME in producing satisfactory short-term outcomes. However, furthermore, larger-scale studies conducted over longer study periods are needed to evaluate the validity of the findings.

Transanal Total Mesorectal Excision for Malignant Rectal Lesion: A Prospective Cohort Study

AIMS: The main outcome of this study was to use the transanal total mesorectal excision (TaTME) technique for rectal cancer resection and to assess as a primary endpoint the short-term oncological outcome; in terms of circumferential resection margin, longitudinal resection margins (proximally and distally), and lymph nodes (LN) retrieval, while secondary endpoints were operative time, estimated blood loss, length of hospital stay, cost per case, and overall complication rate. METHODS: This was a prospective cohort study. Forty patients were included and subjected to TaTME from May 2018 to January 2020 and patients were followed up for a period of 6 months. RESULTS: Primary endpoint: Depending on the post-operative specimen pathological assessment; circumferential resection margin (CRM) was free in all patients, proximal resection margins had a mean 14.37 2.87 cm, distal resection margins had a mean 2.08 ± 0.4 cm and LNs retrieval had a mean 13.27 ± 5.9, and number of positive LNs had a mean 2.40 ± 3.77. Secondary endpoints: Mean total operative time (from induction of anesthesia till skin closure) was 179.10, estimated blood loss (using gauze visual analog plus what was obtained in the OR suction device) was 133.67 66.59 ml, the length of hospital stay (admission till discharge) was 5.27 ± 1.08 days, cost per case had a mean (in 1000 USD) 2.95 ± 0.12, and overall complication rate was 10%. CONCLUSION: TaTME represents a promising complementary technique to laparoscopic TME in the step of low rectal dissection.

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

AIM

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

METHOD

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

RESULTS

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

CONCLUSION

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

A systematic review and meta-analysis of robotic-assisted transabdominal total mesorectal excision and transanal total mesorectal excision: which approach offers optimal short-term outcomes for mid-to-low rectal adenocarcinoma?

BACKGROUND

Resection of low rectal adenocarcinoma can be challenging in the narrow pelvis of male patients. Transanal total mesorectal excision (TaTME) appears to offer technical advantages for distal rectal tumours, and robotic-assisted transabdominal TME (rTME) was introduced in effort to improve operative precision and ergonomics. However, no study has comprehensively compared these approaches. The aim of the present study was to perform a systematic review of the literature to compare postoperative short-term outcomes in rTME and TaTME.

METHODS

A systematic online search (1974-July 2020) of MEDLINE, Embase, web of science and google scholar was conducted for trials, prospective or retrospective studies involving rTME, or TaTME for rectal cancer. Outcome variables included: hospital stay; operation duration, blood loss; resection margins; proportion of histologically complete resected specimens; lymph nodes; overall complications; anastomotic leak, and 30-day mortality.

RESULTS

Sixty-two articles met the inclusion criteria, including 37 studies (3835 patients) assessing rTME resection, 23 studies (1326 patients) involving TaTME and 2 comparing both (165 patients). Operating time was longer in rTME (309.2 min, 95% CI 285.5-332.8) than in TaTME studies (256.2 min, 95% CI 231.5-280.9) (p = 0.002). rTME resected specimens had a larger distal resection margin (2.62 cm, 95% CI 2.35-2.88) than in TaTME studies (2.10 cm, 95% CI 1.83-2.36) (p = 0.007). Other outcome variables did not significantly differ between the two techniques.

CONCLUSIONS

rTME provides similar pathological and short-term outcomes to TaTME and both are reasonable surgical approaches for patients with mid-to-low rectal cancer. To definitively answer the question of the optimal TME technique, we suggest a prospective trial comparing both techniques assessing long-term survival as a primary outcome.

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.

Two-Year Follow-Up of the First Transanal Total Mesorectal Excision (TaTME) Case Performed in Community Hospital in Hawai'i: A Case Report and Literature Review

Surgical management of rectal cancer has evolved with the advent of total mesorectal excision (TME) and neo-adjuvant treatment allowing for more sphincter-preserving proctectomies. The laparoscopic approach to TME has numerous advantages over the open approach, including faster recovery, fewer wound complications, and overall reduced morbidity. However, laparoscopic dissection around the distal portion of the rectum is particularly difficult, and thus makes achieving TME completeness and negative resection margins for low rectal tumors a challenge. Transanal TME (TaTME) is designed to overcome these difficulties. It is performed in addition to laparoscopic operation as a bottom-up approach facilitating dissection around the distal rectum. More importantly, TaTME has been shown to have the potential to improve oncological outcomes of minimally-invasive sphincter-preserving proctectomy by providing better TME specimen quality and resection margins. Although interest in TaTME has been growing worldwide, the technique is still relatively new, and adoption into routine practice may be challenging. Potential criteria for successful adoption of the TaTME technique include experience in laparoscopic rectal resection and transanal minimally-invasive surgery (TAMIS), cadaveric TaTME training, and a multidisciplinary approach to selection and management of patients with rectal cancer. Once these criteria are met, gradual and careful implementation of TaTME could be feasible. This report describes the 2-year follow-up of the first TaTME case in Hawai'i managed by a multidisciplinary oncological team in a community hospital setting.

Education and Training in Transanal Endoscopic Surgery and Transanal Total Mesorectal Excision

There is a paradigm shift in surgical training, and new tool and technology are being used to facilitate mastery of the content and technical skills. The transanal procedures for rectal cancer-transanal endoscopic surgery (TES) and transanal total mesorectal excision (TaTME)-have a distinct learning curve for competence in the procedures, and require special training for familiarity with the "bottom-up" anatomy, procedural risks, and managing complex cases. These procedures have been models for structured education and training, using multimodal tools, to ensure safe implementation of TES and TaTME into clinical practice. The goal of this work was to review the current state of surgical education, the introduction and learning curve of the TES and TaTME procedures, and the established and future models for education of the transanal procedures for rectal cancer.

Robotic or transanal total mesorectal excision (TaTME) approach for rectal cancer, how about both? Feasibility and outcomes from a single institution

Laparoscopic surgery for rectal cancer is technically challenging. Robotic and transanal TME (TaTME) are both novel approaches developed to provide better visualization and dissection. We aim to combine both approaches in a hybrid procedure and evaluate the feasibility as well as patient and oncological outcomes in this study. A review of a prospectively maintained database of patients who underwent a hybrid abdominal robotic approach with TaTME for rectal cancer between January 2016 and October 2018 was undertaken. Patient demographics, tumor characteristics and surgical outcomes were recorded and analyzed. A total of 69 patients (43 males, 26 females) received this hybrid approach. Their median age was 58 years (range 35-87) with a mean BMI of 24.3 kg/m² (range 16.4-44.2). Median distance from anal verge was 5 cm (range 2-9). The patients had a median hospital length of stay of 7 days (range 5-28). Complication rate was 17.4% (12 patients) with 3 patients (4.3%) requiring a reoperation. TME quality was optimal with all of them either complete (81.2%) or almost complete (18.8%). 65 patients (94.2%) had an R0 resection with 4 patients (5.8%) with involved circumferential resection margins (≤ 1 mm). The median number of lymph nodes harvested was 20 (range 6-37). After a median follow-up of 27.7 months (range 7-42), local recurrence was identified in 2 patients (4%). Three patients (5.2%) had distant recurrence at the 3-year mark. Hybrid robotic abdominal dissection with transanal TME for rectal cancer appears to be feasible with comparable surgical outcomes to other traditional approaches.

Association between urinary function and resected pattern of the autonomic nerve system after transanal total mesorectal excision for rectal cancer

AIM

Transanal total mesorectal excision (TaTME) is expected to improve the quality of total mesorectal excision as well as preserve urinary function. We aimed to study the frequency and risk factors of urinary dysfunction in rectal cancer patients after TaTME. Moreover, we analysed the association between urinary function and resected pattern of the autonomic nerve system (ANS) in TaTME.

METHOD

We retrospectively analysed 231 patients who underwent TaTME at our hospital from 2013 to 2018. Independent risk factors for urinary dysfunction were assessed by multivariate analysis. Urinary dysfunction was defined as a condition that requires urethral catheterisation. We intraoperatively judged and classified the preserved or resected pattern of ANS into four categories.

RESULTS

The rate of urinary dysfunction after TaTME was 12.1% at discharge. Multivariate analysis revealed that beyond TME and ANS resection were the two major independent risk factors for urinary dysfunction. Total ANS preservation had reduced rates of urinary dysfunction, and all patients were free from catheterisation 6 months post-surgery. There was a higher rate of urinary dysfunction in total ANS resection than in partial ANS resection at 6 months post-surgery.

CONCLUSION

This study showed that urinary function after TaTME was associated with resection of the ANS. Furthermore, the rate of urinary dysfunction and recovery time were closely related to the pattern of ANS resection.

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.

A Comprehensive Review of Randomized Clinical Trials Shaping the Landscape of Rectal Cancer Therapy

Colorectal carcinoma is the second leading cause of cancer-related deaths in the United States, with rectal cancer accounting for approximately one third of newly diagnosed cases. Surgery remains the cornerstone of curative therapy, with total mesorectal excision being the standard of care. Although minimally invasive procedures might be appropriate for a subset of patients with early-stage, superficial tumors, the standard of care for medically operable patients with nonmetastatic rectal cancer includes a comprehensive multimodality approach of neoadjuvant chemoradiotherapy, surgery with total mesorectal excision, and systemic chemotherapy. However, the morbidity and mortality related to both local and distant organ relapse have remained challenging. In the present review, we have discussed the trial-level evidence that has shaped the current clinical practice patterns in the treatment of curable, nonmetastatic rectal cancer. In addition, we have discussed the anticipated results of ongoing clinical trials and outlined pragmatic opportunities for future investigation to optimize the current status quo and, hopefully, provide prospective validation of novel approaches in the treatment of rectal cancer.

The multidisciplinary management of rectal cancer

Rectal cancer treatment has evolved during the past 40 years with the use of a standardized surgical technique for tumour resection: total mesorectal excision. A dramatic reduction in local recurrence rates and improved survival outcomes have been achieved as consequences of a better understanding of the surgical oncology of rectal cancer, and the advent of adjuvant and neoadjuvant treatments to compliment surgery have paved the way for a multidisciplinary approach to disease management. Further improvements in imaging techniques and the ability to identify prognostic factors such as tumour regression, extramural venous invasion and threatened margins have introduced the concept of decision-making based on preoperative staging information. Modern treatment strategies are underpinned by accurate high-resolution imaging guiding both neoadjuvant therapy and precision surgery, followed by meticulous pathological scrutiny identifying the important prognostic factors for adjuvant chemotherapy. Included in these strategies are organ-sparing approaches and watch-and-wait strategies in selected patients. These pathways rely on the close working of interlinked disciplines within a multidisciplinary team. Such multidisciplinary forums are becoming standard in the treatment of rectal cancer across the UK, Europe and, more recently, the USA. This Review examines the essential components of modern-day management of rectal cancer through a multidisciplinary team approach, providing information that is essential for any practising colorectal surgeon to guide the best patient care.

Transanal total mesorectal excision the Gold Coast experience: learning curve and comparison to traditional technique

BACKGROUND

Laparoscopic and open techniques in rectal cancer are well-published, however, technical challenges remain for mid to low rectal cancer resections in the narrow pelvis. Transanal total mesorectal excision (taTME) has been pioneered to potentially circumvent these challenges. The aims of this study were to evaluate the learning curve associated with our first cases of taTME as well as compare outcomes to that of conventionally performed rectal resections.

METHODS

This was a single-centre retrospective study with data collated from all elective resections by the colorectal unit from 2015 to 2017. Primary outcome was completeness of total mesorectal excision and secondary outcomes were intra- and post-operative morbidity and mortality.

RESULTS

A total of 43 patients were identified. Of which, 20 underwent taTME. Mesorectal completeness was obtained in only 47.4% in the taTME group compared to 78.3% in the anterior resection group (p = 0.115). 5.9% of patients in our taTME group had positive circumferential resection margin compared to nil in the anterior resection. Conversion rates were greater in the taTME group (15% versus 0%; 0.028). Operative time, length of stay and clavien IV and V complications were greater in the taTME group.

CONCLUSION

This study highlights the difficulty in introducing a novel technique given the learning curve. Our results would expect to improve with increased caseload.

Effectiveness and safety of acupuncture and moxibustion for defecation dysfunction after sphincter-preserving surgery for rectal cancer: protocol for systematic review and meta-analysis

INTRODUCTION

Defecation dysfunction (DD) is one of the most common complications following sphincter-preserving surgery for rectal cancer. And there is no effective treatment of DD after sphincter-preserving surgery for rectal cancer. Although some studies suggested that acupuncture and moxibustion (AM) is effective and safe for DD after sphincter-preserving surgery for rectal cancer, lacking strong evidence, for instance, the relevant systematic review, meta-analysis and randomised controlled trial (RCT) of a large, multicentre sample, makes the effects and safety remain uncertain. The present protocol is described for a systematic review and meta-analysis to investigate the effectiveness and safety of AM for DD after sphincter-preserving surgery for rectal cancer.

METHODS AND ANALYSIS

We will search nine online databases from inception to 1 October 2019; the language of included trials will not be restricted. This study will include RCTs that performed AM as the main method of the experimental group for patients with DD after sphincter-preserving surgery for rectal cancer. Two of the researchers will independently select the studies, conduct risk of bias assessment and extract the data. We will use the fixed-effects model or random-effects model of RevMan V.5.2 software to analyse data synthesis. The risk ratios with 95% CIs and weighted mean differences or standardised mean differences with 95% CIs will be used to present the data synthesis outcome of dichotomous data respectively and the continuous data. Evidence quality of outcome will be assessed by using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system.

ETHICS AND DISSEMINATION

Ethical approval is not required in this secondary research evidence, and we will publish the results of this study in a journal or concerned conferences.

TRIAL REGISTRATION NUMBER

CRD42019140097.

Evolution of Transanal Total Mesorectal Excision

Minimally invasive techniques continue to transform the field of colorectal surgery. Because traditional surgical approaches for rectal cancer are associated with significant mortality and morbidity, developing less invasive approaches to this disease is paramount. Natural orifice transluminal endoscopic surgery (NOTES), commonly known as "no incision surgery," represents the ultimate minimally invasive approach to disease. Although transgastric and transvaginal approaches for NOTES surgery were the initially explored, a transrectal approach for colorectal disease is intuitive given that it makes use of the resected organ for transluminal access. Furthermore, the transanal approach allows for improved, precise visualization of the presacral mesorectal plane compared with an abdominal viewpoint, particularly in the narrow, male pelvis. Finally, experience with existing transanal platforms that have been used for decades for local excision of rectal disease made the development of a transanal approach to total mesorectal excision (TME) feasible. Here, we will review the evolution of minimally invasive and transanal surgical techniques that allowed for the development of transanal TME and its introduction into clinical practice.

Essential advances in surgical and adjuvant therapies for colorectal cancer 2018-2019

Surgical resection and adjuvant chemotherapy are the only treatment modalities for localized colorectal cancer that can obtain a "cure." The goal in surgically treating primary colorectal cancer is complete tumor removal along with dissection of systematic D3 lymph nodes. Adjuvant treatment controls recurrence and improves the prognosis of patients after they undergo R0 resection. Various clinical studies have promoted the gradual spread and clinical use of new surgical approaches such as laparoscopic surgery, robotic surgery, and transanal total mesorectal excision (TaTME). Additionally, the significance of adjuvant chemotherapy has been established and it is now recommended in the JSCCR (the Japanese Society for Cancer of the Colon and Rectum) guideline as a standard treatment. Herein, we review and summarize current surgical treatment and adjuvant chemotherapy for localized colorectal cancer and discuss recent advances in personalized medicine related to adjuvant chemotherapy.

Evolution of surgery for rectal cancer: Transanal total mesorectal excision～new standard or fad?～

Transanal Total Mesorectal Excision (TaTME) has recently been developed to overcome the difficulties associated with conventional laparoscopic or robotic TME. TaTME has gained popularity and becomes the center of attention among colorectal surgeons globally. The present review aims to update the literature, clarify the current status and perspectives of TaTME. Complete TaTME specimens were obtained in 85-97.1% of the case; the reported circumferential resection margin (CRM) ranged from 1.5% to 8.1%, whereas and distal resection margin (DRM) positive rates ranged from 0% to 3.2%. The conversion rate of TaTME occurred from 0 to 15%, and there was no difference between TaTME and laparoscopic or robotic TME. Intraoperative complications occurred in 5-6% of the case, which compared favorably to laparoscopic TME. The most serious intraoperative complication with this approach was urethral injury, although only small numbers were reported, which was possibly due to under-reporting. Clavien-Dindo I or II postoperative complications occurred in 22-24% of the case, and III or IV in 10-11% of the case, which did not differ between TaTME and laparoscopic or robotic TME. TaTME may be technically easier and more beneficial than laparoscopic, robotic or open TME in male patients with a narrow pelvis; in obese patients with a bulky tumor. At present two randomized controlled trials, COLOR III and GRECCAR, and comparing TaTME with laparoscopic TME are being conducted and their outcomes are awaited. TaTME is a complex procedure, but proved to be feasible, oncologically safe, and effective in difficult cases. Before this new technique is adopted, proper training with Proctor/mentorship is strongly advised. Careful case selection and audit of data are mandatory.

Urethral Injury and Other Urologic Injuries During Transanal Total Mesorectal Excision: An International Collaborative Study

OBJECTIVE

To identify risk factors for urethral and urologic injuries during transanal total mesorectal excision (taTME) and evaluate outcomes.

BACKGROUND

Urethral injury is a rare complication of abdominoperineal resection (APR) that has not been reported during abdominal proctectomy. The Low Rectal Cancer Development Program international taTME registry recently reported a 0.8% incidence, but actual incidence and mechanisms of injury remain largely unknown.

METHODS

A retrospective analysis of taTME cases complicated by urologic injury was conducted. Patient demographics, tumor characteristics, intraoperative details, and outcomes were analyzed, along with surgeons' experience and training in taTME. Surgeons' opinion of contributing factors and best approaches to avoid injuries were evaluated.

RESULTS

Thirty-four urethral, 2 ureteral, and 3 bladder injuries were reported during taTME operations performed over 7 years by 32 surgical teams. Twenty injuries occurred during the teams' first 8 taTME cases ("early experience"), whereas the remainder occurred between the 12th to 101st case. Injuries resulted in a 22% conversion rate and 8% rate of unplanned APR or Hartmann procedure. At median follow-up of 27.6 months (range, 3-85), the urethral repair complication rate was 26% with a 9% rate of failed urethral repair requiring permanent urinary diversion. In patients with successful repair, 18% reported persistent urinary dysfunction.

CONCLUSIONS

Urologic injuries result in substantial morbidity. Our survey indicated that those occurring in surgeons' early experience might best be reduced by implementation of structured taTME training and proctoring, whereas those occurring later relate to case complexity and may be avoided by more stringent case selection.

Evolution of transanal total mesorectal excision according to the IDEAL framework

Tremendous innovations have taken place in surgical procedures, but contrary to drug development, this process has been unregulated in the past. IDEAL promotes a structured framework for the safe implementation and assessment of a new surgical technique or intervention, by describing five stages for evaluating and reporting of innovations: Idea, Development, Exploration, Assessment and Long term. Transanal total mesorectal excision (TaTME) is a relatively new technique in rectal cancer surgery that has attracted huge interest and increasing adoption worldwide. This review article aims to provide an overview of the evolution of TaTME, according to the IDEAL framework, which guides us in the difficult yet exciting process of surgical innovation.

Cost-effectiveness of current approaches in rectal surgery

Colorectal cancer is ranked as the fourth malignant cause of mortality. With the tremendous revolution in the modern medical techniques, minimally invasive approaches have been incorporated into rectal surgery. The effectiveness of surgical procedures is usually measured by a combination of qualitative (quality of life) and quantitative (years of life) measures, while the costs should reflect the use of different resources that were involved in delivering the medical care and they are affected by several factors, including length of hospital stay. In this review, we provide an insight into the cost-effectiveness of the different types of rectal surgeries in order to present a systematic approach for future preferences. A comprehensive literature review using Medline (via PUBMED), Embase and Cochrane Central Register of clinical trials (via clinical trial.org) was performed. Minimally invasive rectal surgeries have considerable cost-effective properties that outweigh those of the open techniques in terms of earlier return to bowel function, lower morbidity rates, reduced pain, shorter length of hospital stay and the overall patients’ quality of life although there was no difference in long-term oncological and survival outcomes. The paucity of currently available long-term oncologic, quality of life, and economic outcomes may limit an adequate comparison of robotic surgeries to other surgical techniques. It is therefore recommended to conduct focused studies to help balance the cost/benefit factors along with other technical considerations aimed at reducing the cost of robotic systems with subsequent improvement of their cost-effectiveness.

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Colorectal cancer is the fourth cause of mortality. Minimally invasive surgery is now considered the standard of care.

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Cost of minimally invasive surgery is offset by the better outcomes due to less complications and shorter hospital stay.

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TaTME requires two working teams and two sets of instruments which increases the total cost.

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Robotic surgery in obese patients demonstrated superior results when it comes to hospital stay and overall complications.

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Well conducted clinical trials looking at cost effectiveness of new technologies in colorectal surgery are needed.

Transanal total mesorectal excision (TaTME): current status and future perspectives

Total mesorectal excision (TME) is the gold standard surgical treatment for mid- and low rectal cancer; however, it is associated with specific technical hurdles. Transanal TME (TaTME) is a new procedure developed to overcome these difficulties, through an enhanced visualization of the dissection plane. This potentially could result in a more accurate distal dissection with a lower rate of positive circumferential resection margins, increasing the rate of sphincter-saving procedures. The indications for TaTME are currently expanding, despite not being yet standardized, and structured training programs are ongoing to help overcome the steep learning curve related to the technique. The procedure is feasible and safe with similar intraoperative complications and readmission rates when compared with conventional open or laparoscopic TME. Favorable short-term oncologic results have been reported: in particular, TaTME is associated with mesorectal specimen of a better quality and a longer distal resection margin that is established at the beginning of the procedure under direct view. Robotics, when available, will probably overcome the steep learning curve related to the complexity of TaTME. Long-term follow-up and ongoing RCT trials data are awaited regarding functional results, local recurrence and survival, and to facilitate the comparison with standard laparoscopic or robotic rectal resections. The present review is focused on critically analyzing the theoretical benefits and risks of the procedure, its indications, short- and long-term results and future direction in the application of TaTME.

The current state of the transanal approach to the ileal pouch-anal anastomosis

BACKGROUND

The transanal approach to pelvic dissection has gained considerable traction and utilization continues to expand, fueled by the transanal total mesorectal excision (TaTME) for rectal cancer. The same principles and benefits of transanal pelvic dissection may apply to the transanal restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA)-the TaPouch procedure. Our goal was to review the literature to date on the development and current state of the TaPouch.

MATERIALS AND METHODS

We performed a PubMed database search for original articles on transanal pelvic dissections, IPAA, and the TaPouch procedure, with a manual search from relevant citations in the reference list. The main outcomes were the technical aspects of the TaPouch, clinical and functional outcomes, and potential advantages, drawbacks, and future direction for the procedure.

RESULTS

The conduct of the procedure has been defined, with the safety and feasibility demonstrated in small series. The reported rates of conversion and anastomotic leakage are low. There are no randomized trials or large-scale comparative studies available for comparative effectiveness compared to the traditional IPAA.

CONCLUSIONS

The transanal approach to ileal pouch-anal anastomosis is an exciting adaption of the transanal total mesorectal excision for refining the technical steps of a complex operation. Additional experience is needed for comparative outcomes and defining the ideal training and implementation pathways.

Systematic review analysis of robotic and transanal approaches in TME surgery- A systematic review of the current literature in regard to challenges in rectal cancer surgery

Several patients' and pathological characteristics in rectal surgery can significantly complicate surgical loco regional tumor clearance. The main factors are obesity, short tumor distance from anal verge, bulky tumors, and narrow pelvis, which have been shown to be associated to poor surgical results in open and laparoscopic approaches. Minimally invasive surgery has the potential to reduce perioperative morbidity with equivalent short- and long-term oncological outcomes compared to conventional open approach. Achilles' heel of laparoscopic approaches is conversion to open surgery. High risk for conversion is evident for patients with bulky and low tumors as well as male gender and narrow pelvis. Hence, patient's characteristics represent challenges in rectal cancer surgery especially in minimally invasive approaches. The available surgical techniques increased remarkably with recently developed and implemented improvements of minimally invasive rectal cancer surgery. The controversial discussions about sense and purpose of these novel approaches are still ongoing in the literature. Herein, we evaluate, if latest technical advances like transanal approach or robotic assisted surgery have the potential to overcome known challenges and pitfalls in rectal cancer surgery in demanding surgical cases and highlight the role of current minimally invasive approaches in rectal cancer surgery.

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

Background

Transanal total mesorectal excision (TaTME) is emerging as a novel alternative to laparoscopic total mesorectal excision (LaTME). The aim of this study was to compare clinical and pathological results from these two techniques in patients undergoing rectal resections because of low rectal cancer.

Materials and methods

Thirty-five patients undergoing TaTME were matched with 35 patients operated on using LaTME. Composite primary endpoint (complete TME, negative circumferential resection margin [pCRM], and distal resection margin [pDRM]) was used to assess pathological quality specimens. Secondary outcomes included operative and postoperative parameters (operative time, total blood loss, postoperative morbidity, length of stay, 30-day mortality).

Results

Composite primary endpoint was achieved by 85% of subjects in the TaTME group and 82% of subjects in the LaTME group (P=0.66). Mean pCRM was 1.1±1.29 vs 0.99±0.78 mm (P=0.25). Distal pDRM was 1.57±0.92 and 1.98±1.22 cm (P=0.15). In the TaTME and LaTME groups, respectively, complete mesorectal excision was achieved in 89% and 83% of subjects, while excision was nearly complete for the remaining 11% and 17% (P=0.23).

Conclusion

TaTME appears to be a noninferior alternative to laparoscopic surgery. TaTME allows for quality retrieval of surgical specimens with comparable clinical outcomes with LaTME.

Pure natural orifice transluminal endoscopic surgery for rectal cancer: Ta-TME and CME without abdominal assistance

AIM

To report our institution's experiences with pure transanal total mesorectal excision (TME) of rectal cancer using single-port equipment and to discuss the feasibility and safety of the technique.

METHODS

Between February and December 2017, 12 patients who were selected underwent NOTES TME in our institution. The preoperative assessment included blood analyses with carcinoembryonic antigen serum concentration, full colonoscopy, pelvic magnetic resonance imaging (MRI), and computed tomography (CT) of the abdomen and chest.

RESULTS

Ten patients (male:female, 6:4) treated with transanal TME with colorectal anastomosis in our institution were reviewed. Pure TME was performed without laparoscopic assistance in 6 of 10 patients. The mean operative time was 303.5 min. The median distal margin was 2.1 (0.2-4.2) cm. The median number of harvested lymph nodes is 17.5. Except one patient with anastomotic leak, most patients started dietary intake on postoperative day (POD) 3 and were discharged on POD 7. Anastomotic leak was the only postoperative complication.

CONCLUSION

This study showed that pure natural orifice transluminal endoscopic surgery (NOTES) TME with coloanal anastomosis for rectal cancer is safe and feasible in selected cases.

Transanal transabdominal TME: how far can we push it?

Over many decades, advances in surgical technology, such as the use of the electrocautery Bovie, development of minimally invasive and advanced endoscopic platforms and the ability to create and maintain pneumorectum have propelled surgical techniques forward to today, with development of the transanal total mesorectal excision TME (taTME) for en bloc resection of rectal cancers. The transanal platform offers, for now, a viable alternative to perform safe and oncologically sound TME, especially favorable in cases of low rectal lesions in a narrow pelvis post neoadjuvant treatment. The aspiration of the colorectal community remains to continue to push the operative boundaries whilst maintaining safe oncological principals with the best possible functional outcomes for patients. In this article we review this evolving technique and focus on future directions.

Alterations of anal physiological features after surgery for low rectal cancer and management strategies

The sphincter preserving operation has improved the quality of life (QOL) of patients with low rectal cancer. However, some patients complain of having postoperative fecal incontinence and low QOL due to sphincter injury, nerve injure, and decreased rectal capacity. Therefore, anal physiology evaluation must be done preoperatively, the sphincter muscle and nerve should be preserved in operation, and biofeedback treatment should be administered postoperatively.

Evolution of transanal total mesorectal excision for rectal cancer: From top to bottom

The gold standard for curative treatment of locally advanced rectal cancer involves radical resection with a total mesorectal excision (TME). TME is the most effective treatment strategy to reduce local recurrence and improve survival outcomes regardless of the surgical platform used. However, there are associated morbidities, functional consequences, and quality of life (QoL) issues associated with TME; these risks must be considered during the modern-day multidisciplinary treatment for rectal cancer. This has led to the development of new surgical techniques to improve patient, oncologic, and QoL outcomes. In this work, we review the evolution of TME to the transanal total mesorectal excision (TaTME) through more traditional minimally invasive platforms. The review the development, safety and feasibility, proposed benefits and risks of the procedure, implementation and education models, and future direction for research and implementation of the TaTME in colorectal surgery. While satisfactory short-term results have been reported, the procedure is in its infancy, and long term outcomes and definitive results from controlled trials are pending. As evidence for safety and feasibility accumulates, structured training programs to standardize teaching, training, and safe expansion will aid the safe spread of the TaTME.

Recent updates in the surgical treatment of colorectal cancer

Because of recent advances in medical technology and new findings of clinical trials, treatment options for colorectal cancer are evolutionally changing, even in the last few years. Therefore, we need to update the treatment options and strategies so that patients can receive optimal and tailored treatment. The present review aimed to elucidate the recent global trends and update the surgical treatment strategies in colorectal cancer by citing the literature published in the last 2 years, namely 2016 and 2017. Although laparoscopic surgery is still considered the most common approach for the treatment of colorectal cancer, new surgical technologies such as transanal total mesorectal excision, robotic surgery, and laparoscopic lateral pelvic lymph node dissection are emerging. However, with the recent evidence, superiority of the laparoscopic approach to the open approach for rectal cancer seems to be controversial. Surgeons should notice the risk of adverse outcomes associated with unfounded and uncontrolled use of these novel techniques. Many promising results are accumulating in preoperative and postoperative treatment including chemotherapy, chemoradiotherapy, and targeted therapy. Development of new biomarkers seems to be essential for further improvement in the treatment outcomes of colorectal cancer patients.

Minimally Invasive Surgery for Rectal Cancer: Current Status and Future Perspectives

Although laparoscopic resection for colon cancer has been proven safe and feasible when compared with open resection, currently no clear evidence is available regarding minimally invasive surgery for rectal cancer. This type of surgery may benefit patients by allowing fast recovery of normal dietary intake and bowel function, reduced postoperative pain, and shorter hospitalization. Therefore, minimally invasive surgeries such as laparoscopic or robot surgery have become the predominant treatment option for colon cancer. Specifically, the proportion of laparoscopic colorectal cancer surgery in Korea increased from 42.6 to 64.7% until 2013. However, laparoscopic surgery for rectal cancer is more difficult and technically demanding. In addition, the procedure requires a prolonged learning curve to achieve equivalent outcomes relative to open surgery. It is very challenging to approach the deep and narrow pelvis using laparoscopic instruments. However, robotic surgery provides better vision with a high definition three-dimensional view, exceptional ergonomics, Endowrist technology, enhanced dexterity of movement, and a lack of physiologic tremor, facilitated by the use of an assistant in the narrow and deep pelvis. Recently, an increasing number of reports have compared the outcomes of laparoscopic and open surgery for colon cancer. Such reports have prompted a discussion of the outcomes of minimally invasive surgery, including robotic surgery, for rectal cancer. The aim of this review is to summarize current data regarding the clinical outcomes, including oncologic outcomes, of minimally invasive surgery for rectal cancer.

Transanal Total Mesorectal Excision: International Registry Results of the First 720 Cases

OBJECTIVE

This study aims to report short-term clinical and oncological outcomes from the international transanal Total Mesorectal Excision (taTME) registry for benign and malignant rectal pathology.

BACKGROUND

TaTME is the latest minimally invasive transanal technique pioneered to facilitate difficult pelvic dissections. Outcomes have been published from small cohorts, but larger series can further assess the safety and efficacy of taTME in the wider surgical population.

METHODS

Data were analyzed from 66 registered units in 23 countries. The primary endpoint was "good-quality TME surgery." Secondary endpoints were short-term adverse events. Univariate and multivariate regression analyses were used to identify independent predictors of poor specimen outcome.

RESULTS

A total of 720 consecutively registered cases were analyzed comprising 634 patients with rectal cancer and 86 with benign pathology. Approximately, 67% were males with mean BMI 26.5 kg/m. Abdominal or perineal conversion was 6.3% and 2.8%, respectively. Intact TME specimens were achieved in 85%, with minor defects in 11% and major defects in 4%. R1 resection rate was 2.7%. Postoperative mortality and morbidity were 0.5% and 32.6% respectively. Risk factors for poor specimen outcome (suboptimal TME specimen, perforation, and/or R1 resection) on multivariate analysis were positive CRM on staging MRI, low rectal tumor <2 cm from anorectal junction, and laparoscopic transabdominal posterior dissection to <4 cm from anal verge.

CONCLUSIONS

TaTME appears to be an oncologically safe and effective technique for distal mesorectal dissection with acceptable short-term patient outcomes and good specimen quality. Ongoing structured training and the upcoming randomized controlled trials are needed to assess the technique further.

Transanal Total Mesorectal Excision: A Novel Approach to Rectal Surgery

Less invasive approaches continue to be explored and refined for diseases of the colon and rectum. The current gold standard for the surgical treatment of rectal cancer, total mesorectal excision (TME), is a technically precise yet demanding procedure with outcomes measured by both oncologic and functional outcomes (including bowel, urinary, and sexual). To date, the minimally invasive approach to rectal cancer has not yet been perfected, leaving ample opportunity for rectal surgeons to innovate. Transanal TME has recently emerged as a safe and effective technique for both benign and malignant diseases of the rectum. While widespread acceptance of this surgical approach remains tempered at this time due to lack of long-term oncologic outcome data, short-term outcomes are promising and there is great excitement surrounding the promise of this technique.

Abdomino-endoscopic perineal excision of the rectum for benign and malignant pathology: Technique considerations for true transperineal verus transanal total mesorectal excision endoscopic proctectomy

PURPOSE

Transanal minimally invasive surgery using single port instrumentation is now well described for the performance of total mesorectal excision with restorative colorectal/anal anastomosis most-often in conjunction with transabdominal multiport assistance. While non-restorative abdomino-endoscopic perineal excision of the anorectum is conceptually similar, it has been less detailed in the literature.

METHODS

Consecutive patients undergoing non-restorative ano-proctectomy including a transperineal endoscopic component were analysed. All cases commenced laparoscopically with initial medial to lateral mobilisation of any left colon and upper rectum. The lower anorectal dissection started via an intersphincteric or extrasphincteric incision for benign and malignant pathology, respectively, and following suture closure and circumferential mobilisation of the anorectum, a single port (GelPOINT Path, Applied Medical) was positioned allowing the procedure progress endoscopically in all quadrants up to the cephalad dissection level. Standard laparoscopic instrumentation was used. Specimens were removed perineally.

RESULTS

Of the 13 patients (median age 55 years, median BMI 28.75 kg/m2, median follow-up 17 months, 6 males), ten needed completion proctectomy for ulcerative colitis following prior total colectomy (three with concomitant parastomal hernia repair) while three required abdominoperineal resection for locally advanced rectal cancer following neoadjuvant chemoradiotherapy. Median operative time was 190 min, median post-operative discharge day was 7. Eleven specimens were of high quality. Four patients developed perineal wound complications (one chronic sinus, two abscesses needing drainage) within median 17-month follow-up.

CONCLUSION

Convergence of transabdominal and transanal technology and technique allows accuracy in combination operative performance. Nuanced appreciation of transperineal operative access should allow specified standardisation and innovation.

Clinical outcomes and case volume effect of transanal total mesorectal excision for rectal cancer: a systematic review

Transanal total mesorectal excision (TaTME) has been developed to improve quality of TME for patients with mid and low rectal cancer. However, despite enthusiastic uptake and teaching facilities, concern exists for safe introduction. TaTME is a complex procedure and potentially a learning curve will hamper clinical outcome. With this systematic review, we aim to provide data regarding morbidity and safety of TaTME. A systematic literature search was performed in MEDLINE (PubMed), EMBASE (Ovid) and Cochrane Library. Case reports, cohort series and comparative series on TaTME for rectal cancer were included. To evaluate a potential effect of case volume, low-volume centres (n ≤ 30 total volume) were compared with high-volume centres (n > 30 total volume). Thirty-three studies were identified (three case reports, 25 case series, five comparative studies), including 794 patients. Conversion was performed in 3.0% of the procedures. The complication rate was 40.3, and 11.5% were major complications. The quality of the mesorectum was “complete” in 87.6%, and the circumferential resection margin (CRM) was involved in 4.7%. In low- versus high-volume centres, the conversion rate was 4.3 versus 2.7%, and major complication rates were 12.2 versus 10.5%, respectively. TME quality was “complete” in 80.5 versus 89.7%, and CRM involvement was 4.8 and 4.5% in low- versus high-volume centres, respectively. TaTME for mid and low rectal cancer is a promising technique; however, it is associated with considerable morbidity. Safe implementation of the TaTME should include proctoring and quality assurance preferably within a trial setting.

Transanal total mesorectal excision for rectal cancer: the journey towards a new technique and its current status

INTRODUCTION

The surgical approach to total mesorectal excision (TME) for rectal cancer has undergone a substantial evolution with the adoption of more minimally invasive procedures. Transanal TME (taTME) is the latest advanced technique pioneered to tackle difficult pelvic dissections. Areas covered: The evolution of TME surgery from open to laparoscopic, robotic and transanal techniques was explored in this review. The outcomes to date on the latest approach, taTME, are reviewed and the future direction of rectal cancer surgery proposed. A literature search was performed using Embase, Medline, Web of Science and Cochrane databases for articles published between January 2005 to May 2016 using the keywords 'transanal', 'TME', 'laparoscopy', 'robotics', 'minimally invasive', 'outcomes' and 'training'. Expert commentary: Surgical experience in taTME is growing and randomised controlled trials have been planned and initiated worldwide. However, the learning curve for this procedure remains to be established and a structured training programme is necessary to ensure safe introduction and dissemination of the technique in the clinical setting. Further innovation including stereotactic navigation and more specialised transanal equipment are currently being explored and are likely to enhance the technique further.

Technologies, technical steps, and early postoperative results of transanal TME

INTRODUCTION

First described in 1982, TME overcomes most of the concerns regarding adequate local control after anterior rectal resection. TME requires close sharp dissection along the so-called Heald's plane down to the levators, with distal dissection often cumbersome. In recent years, Transanal TME was introduced with the aim to improve distal rectal dissection and quality of mesorectal excision.

MATERIAL AND METHODS

A prospective, non-randomized study, started in 2013, is currently ongoing in two Italian Centers. Study objectives were assessing the safety of TaTME and TME quality. TaTME technique and technologies as performed in these centers and cumulative results at ≤30 postoperative days of the first 102 patients are reported.

RESULTS

Early postoperative morbidity and mortality rates were 33.3% (34 pts, 16 Clavien-Dindo I + II and 18 Clavien-Dindo III + IV + V), and 1.96% (two deaths), respectively. The quality of mesorectal excision according to Quirke was: complete in 97.1% and nearly complete in 2.9% of the cases.

CONCLUSIONS

The results confirm the effectiveness of TaTME, especially regarding the quality of the mesorectal dissection. Open questions regarding standardization, anatomical landmarks, indications, morbidity (with special regard to local infection and sepsis), learning curve and oncological outcomes require further answers from larger studies and RCTs before definitive validation of this procedure.  .

Transanal total mesorectal excision (taTME) for rectal cancer: a systematic review and meta-analysis of oncological and perioperative outcomes compared with laparoscopic total mesorectal excision

Background

Transanal total mesorectal excision (taTME) is an emerging surgical technique for rectal cancer. However, the oncological and perioperative outcomes are controversial when compared with conventional laparoscopic total mesorectal excision (laTME).

Methods

A systematic review and meta-analysis based on Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines was conducted in PubMed, Embase and Cochrane database. All original studies published in English that compared taTME with laTME were included for critical appraisal and meta-analysis. Data synthesis and statistical analysis were carried out using RevMan 5.3 software.

Results

A total of seven studies including 573 patients (taTME group = 270; laTME group = 303) were included in our meta-analysis. Concerning the oncological outcomes, no differences were observed in harvested lymph nodes, distal resection margin (DRM) and positive DRM between the two groups. However, the taTME group showed a higher rate of achievement of complete grading of mesorectal quality (OR = 1.75, 95% CI = 1.02–3.01, P = 0.04), a longer circumferential resection margin (CRM) and less involvement of positive CRM (CRM: WMD = 0.96, 95% CI = 0.60–1.31, P <0.01; positive CRM: OR = 0.39, 95% CI = 0.17–0.86, P = 0.02). Concerning the perioperative outcomes, the results for hospital stay, intraoperative complications and readmission were comparable between the two groups. However, the taTME group showed shorter operation times (WMD = –23.45, 95% CI = –37.43 to –9.46, P <0.01), a lower rate of conversion (OR = 0.29, 95% CI = 0.11–0.81, P = 0.02) and a higher rate of mobilization of the splenic flexure (OR = 2.34, 95% CI = 0.99–5.54, P = 0.05). Although the incidence of anastomotic leakage, ileus and urinary morbidity showed no difference between the groups, a significantly lower rate of overall postoperative complications (OR = 0.65, 95% CI = 0.45–0.95, P = 0.03) was observed in the taTME group.

Conclusions

In comparison with laTME, taTME seems to achieve comparable technical success with acceptable oncologic and perioperative outcomes. However, multicenter randomized controlled trials are required to further evaluate the efficacy and safety of taTME.

Transanal total mesorectal excision: surgical technique description and outcomes

Minimally invasive techniques (MIS) have been evolving quickly in colorectal surgery during the last two decades. Transanal total mesorectal excision (taTME) was developed as a combination of skills acquired from different MIS approaches such as Transanal Endoscopic Microsurgery (TEM), Transanal Minimally Invasive Surgery (TAMIS) and Natural Orifices Transluminal Endoscopic Surgery (NOTES). TaTME allows for a better visualization of surgical planes of dissection and achievement of rectal resection following oncologic principles. We here present the standardized taTME technique in use at the Hospital Clínic de Barcelona and our published outcomes in rectal cancer.