Transanal minimally invasive surgery: a giant leap forward. Surg Endosc. 2010;24:2200-2205. [PMID: 20174935 DOI: 10.1007/s00464-010-0927-z]

Initial Experience With Trans-anal Minimally Invasive Surgery (TAMIS) for Rectal Polyps and Early Colorectal Cancers at Cumberland Infirmary, Carlisle

INTRODUCTION

Bowel cancer is the fourth most common type of cancer in the United Kingdom in 2019. Total mesorectal excision is the standard procedure for the removal of rectal tumors, however, it comes with serious side effects. Therefore, less invasive procedures and sphincter preservation techniques have been developed, like conventional trans-anal excision, and trans-anal endoscopic microsurgery (TEM). In 2010, trans-anal minimally invasive surgery (TAMIS) was introduced as an alternative to TEM, which offers the same benefits as TEM but at a lower cost and without the need for specialized instrumentation. This study aims to assess the practicability and safety of this technique and to report its findings.  Methods: Retrospective data of all patients who underwent TAMIS at Cumberland Infirmary (Carlisle, UK) from July 2017 to July 2022 for large benign rectal polyps or early rectal cancer were collected. Variables collected included patients' age, gender, number of procedures per year, perioperative outcome, and histopathology outcome. The SPSS version 21 (IBM Corp., Armonk, NY, USA) was used for both descriptive and inferential analyses of the data.

RESULTS

During a five-year period, 42 patients underwent TAMIS at Cumberland Infirmary. The primary indication for TAMIS was distal rectal lesions, large rectal polyps up to 120 mm, and early rectal cancer (T1). The median age of the assessed patients at the time of surgery was 71 years with 64.29% (27) male and 35.71% (15) female. The mean operating time was 123 minutes (range 45 to 240 minutes). The surgical and pathological outcome included a mean polyp size of 6 cm (+/- 0.8 cm), a rate of specimen fragmentation at 19.04% (n=8), and a rate of positive margins at 04.76% (n=2), whereas histology of 73.81% (n=31) was tubulovillous adenoma and 11.91% (n=5) was adenocarcinoma. There was no 30-day postoperative mortality, however, the 30-day re-operation rate was 02.39% (n=1) and the recurrence rate which needed further intervention was 26.19% (n=11).

CONCLUSION

Our findings suggest that TAMIS produces positive results. The size of the lesions removed, and the effect of an early learning curve are reflected in the rate of specimen fragmentation and polyp recurrence. Nonetheless, TAMIS is a safe and effective alternative to total mesorectal excision for certain types of rectal lesions and should be used for more proximal and complex rectal lesions.

Novel "resect and analysis" approach for T2 colorectal cancer with use of artificial intelligence

BACKGROUND AND AIMS

Because of a lack of reliable preoperative prediction of lymph node involvement in early-stage T2 colorectal cancer (CRC), surgical resection is the current standard treatment. This leads to overtreatment because only 25% of T2 CRC patients turn out to have lymph node metastasis (LNM). We assessed a novel artificial intelligence (AI) system to predict LNM in T2 CRC to ascertain patients who can be safely treated with less-invasive endoscopic resection such as endoscopic full-thickness resection and do not need surgery.

METHODS

We included 511 consecutive patients who had surgical resection with T2 CRC from 2001 to 2016; 411 patients (2001-2014) were used as a training set for the random forest-based AI prediction tool, and 100 patients (2014-2016) were used to validate the AI tool performance. The AI algorithm included 8 clinicopathologic variables (patient age and sex, tumor size and location, lymphatic invasion, vascular invasion, histologic differentiation, and serum carcinoembryonic antigen level) and predicted the likelihood of LNM by receiver-operating characteristics using area under the curve (AUC) estimates.

RESULTS

Rates of LNM in the training and validation datasets were 26% (106/411) and 28% (28/100), respectively. The AUC of the AI algorithm for the validation cohort was .93. With 96% sensitivity (95% confidence interval, 90%-99%), specificity was 88% (95% confidence interval, 80%-94%). In this case, 64% of patients could avoid surgery, whereas 1.6% of patients with LNM would lose a chance to receive surgery.

CONCLUSIONS

Our proposed AI prediction model has a potential to reduce unnecessary surgery for patients with T2 CRC with very little risk. (Clinical trial registration number: UMIN 000038257.).

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

Purpose

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

Methods

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

Results

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

Conclusions

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

Supplementary Information

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

Transanal Minimally Invasive Surgery for Rectal Anastomotic Stenosis After Colorectal Cancer Surgery

BACKGROUND

Anastomotic stenosis is a common complication of colorectal cancer surgery with anastomosis. Transanal minimally invasive surgery is a novel approach to the treatment of anastomotic stenosis.

OBJECTIVE

This study aimed to evaluate the efficacy and safety of transanal minimally invasive surgery for anastomotic stenosis treatment.

DESIGN

This was a retrospective study.

SETTINGS

This study was conducted at a comprehensive cancer center.

PATIENTS

This study included patients with rectal anastomotic stenosis who after undergoing colorectal surgery were admitted to the Sir Run Run Shaw Hospital between September 2017 and June 2019.

MAIN OUTCOME MEASURES

The primary outcome was the operative success rate. The secondary outcomes were intraoperative variables, postoperative complications, stoma closure conditions, and stenosis recurrence risks.

RESULTS

Nine patients, aged 52 to 80 years, with a history of colorectal cancer with end-to-end anastomosis underwent transanal minimally invasive surgery for anastomotic stenosis. The distance between the stenosis and the anal verge ranged from 5 to 12 cm. The mean stenosis diameter was 0.3 cm. Four patients had completely obstructed rectal lumens. Eight of 9 patients successfully underwent transanal minimally invasive surgery radial incision and cutting. The average operation time was 50 minutes. After the procedure, 1 patient had symptomatic procedure-associated perforations but recovered with conservative treatment. No perioperative mortality occurred. One patient underwent transverse colostomy 1 month after transanal minimally invasive surgery because of proximal colon ischemia induced by primary rectal surgery. Eight patients underwent protective loop ileostomy. After transanal minimally invasive surgery, stoma closure was performed in 88% of patients with no stenosis recurrence or obstruction at follow-up (21-42 mo).

LIMITATIONS

This study was limited by its small sample size and single-center design.

CONCLUSIONS

Transanal minimally invasive surgery provides an excellent operative field, good maneuverability, and versatile instrumentation and is a safe and effective treatment for rectal anastomotic stenosis, especially for severe fibrotic stenosis or complete obstruction. See Dynamic Article Video at http://links.lww.com/DCR/B965 .

Mesentery in Transanal TME

Oncological adequacy in rectal cancer surgery mandates not only a clear distal and circumferential resection margin but also resection of the entire ontogenetic mesorectal package. Incomplete removal of the mesentery is one of the commonest causes of local recurrences. The completeness of the resection is not only determined by tumor and patient related factors but also by the patient-tailored treatment selected by the multidisciplinary team. This is performed in the context of the technical ability and experience of the surgeon to ensure an optimal total mesorectal excision (TME). In TME, popularized by Professor Heald in the early 1980s as a sharp dissection through the avascular embryologic plane, the midline pedicle of tumor and mesorectum is separated from the surrounding, mostly paired structures of the retroperitoneum. Although TME significantly improved the oncological and functional results of rectal cancer surgery, the difficulty of the procedure is still mainly dependent on and determined by the dissection of the most distal part of the rectum and mesorectum. To overcome some of the limitations of working in the narrowest part of the pelvis, robotic and transanal surgery have been shown to improve the access and quality of resection in minimally invasive techniques. Whatever technique is chosen to perform a TME, embryologically derived planes and anatomical points of reference should be identified to guide the surgery. Standardization of the chosen technique, widespread education, and training of surgeons, as well as caseloads per surgeon, are important factors to optimize outcomes. In this article, we discuss the introduction of transanal TME, with emphasis on the mesentery, relevant anatomy, standard procedural steps, and importance of a training pathway.

Randomized experimental study of two novel techniques for transanal repair of dehiscent low rectal anastomosis

BACKGROUND

Anastomotic leak after low anterior rectal resection is a dreadful complication. Early diagnosis, prompt management of sepsis followed by closure of anastomotic defect may increase chances of anastomotic salvage. In this randomized experimental study, we evaluated two different methods of trans-anal anastomotic repair.

METHODS

A model of anastomotic leak was created in 42 male pigs. Laparoscopic low anterior resection was performed with anastomosis created using a circular stapler with half of the staples removed. Two days later, animals were randomized into a TAMIS (trans-anal minimally invasive surgery) repair, endoscopic suture (ENDO) or control group with no treatment (CONTROL). Signs of intraabdominal infection (IAI), macroscopic anastomotic healing and burst tests were evaluated to assess closure quality after animals were sacrificed on the ninth postoperative day.

RESULTS

Closure was technically feasible in all 28 animals. Two animals had to be euthanized due to progressive sepsis at four and five days after endoscopic closure. Healed anastomosis with no visible defect was observed in 10/14 and 11/14 animals in TAMIS and ENDO groups, respectively, versus 2/14 in CONTROL (p < 0.05). Overall IAI rate was significantly lower in TAMIS (4/14; p = 0.006) and ENDO (5/14; p = 0.018) compared to CONTROL (12/14). Burst tests confirmed sealed closure in healed anastomosis with a median failure pressure of 190 (110-300) mmHg in TAMIS and 200 (100-300) mmHg in ENDO group (p = 0.644).

CONCLUSION

In this randomized experimental study, we found that both evaluated techniques are effective in early repair of dehiscent colorectal anastomosis with a high healing rate.

Assessment of the learning curve for the novel transanal minimally invasive surgery simulator model

BACKGROUND

Transanal minimally invasive surgery (TAMIS) is technically demanding and requires extensive training. We developed the TAMIS simulator model by remodeling an existing laparoscopic training system to educate trainees and analyzed their learning curves.

METHODS

Between March 2020 and June 2020, 12 trainees performed TAMIS simulator training sessions. The total operative time, including specimen removal and wound closure, was recorded. The wound closure and specimen quality, trainee self-confidence, and supervisor evaluation of technical performance were documented. A moving average was used to analyze the number of training sessions required to stabilize the procedure time, while a cumulative sum analysis was performed to identify that required to reach proficiency with each item.

RESULTS

Each trainee completed 20 TAMIS simulator training sessions. The median total procedure time was 13 min (range, 4-60 min), which stabilized after 15 training sessions. The median times for specimen removal and wound closure were 3 min (range, 1-18 min) and 10 min (range, 2-50 min), respectively, which stabilized after 7 and 15 training sessions, respectively. The mean specimen and wound closure quality scores were 2.9 ± 0.9 (on a scale from 1 to 4) and 2.3 ± 1.1 (on a scale from 1 to 4), respectively, competencies in which were achieved after 16 and 20 training sessions, respectively. The mean trainee self-confidence and supervisor evaluation of technical performance scores were 2.4 ± 1.2 (on a scale from 1 to 5) and 2.7 ± 1.2 (on a scale from 1 to 5), respectively, competencies in which were achieved after 20 and 17 training sessions, respectively.

CONCLUSION

Trainees required 15 training sessions to stabilize the procedure time and 16-20 training sessions to demonstrate competencies with the TAMIS simulator model. We expect this simulator model may help surgeons more rapidly acquire the skills required for TAMIS.

Redo surgery after low anterior resection for chronic pelvic sinus and anastomotic disruption. Could pull-through procedure with delayed anastomosis be a feasible alternative? Case reports and narrative review

INTRODUCTION

A considerable step forward in low rectal cancer resection has been done in the last decades. Maintaining total mesorectal excision as the gold standard treatment, new techniques such as Trans-Anal Mini-Invasive Surgery (TAMIS) and Trans-Anal Total Mesorectal Excision (TATME), which have been added to improve skills in laparoscopic and robotic surgery, currently represent the advancement of this procedure. Despite improvements in surgical techniques, complications after low anterior resection for rectal cancer still remain a challenge. Drainage and colostomy are the main treatments used to overcome the problem caused by anastomosis failure, and most patients will never been restored. Different techniques of redo surgery could be proposed to deal complex cases, although remaining high risk procedures.

CASE PRESENTATION

We present two clinical cases with a late complication of the colorectal anastomosis: one with a late leakage of low colorectal anastomoses, treated with Hartman procedure, that developed a pelvic chronic sinus; the another one with complete anastomotic disruption after massive suture bleeding; both treated with delayed pull-through anastomosis, according to Turnbull-Cutait technique. We also made a review of relative literature, in order to back our therapeutic iters.

DISCUSSION

Both the procedures were carried out satisfactorily, with restoration of intestinal continuity and good anastomotic result. It allows the resolutions of the chronic sepsis caused by the pelvic sinus and maintenance of intestinal continuity with a good Wexner incontinence score. Literary review demonstrated that this procedure still remains undervalued and not widely exploited.

CONCLUSION

Delayed pull-through coloanal anastomosis could be considered as a valid option, in order to preserve intestinal continuity in septic or complicated low colorectal anastomosis.

Recent Advancements in the Treatment of Rectal Gastrointestinal Stromal Tumor: In Era of Imatinib

Gastrointestinal stromal tumors (GIST) are the most common mesenchymal tumor of the gastrointestinal tract, with an annual incidence of 10–15 cases per million. However, rectal GIST has a low incidence, accounting for approximately 0.1% of all rectal tumors. The treatment of rectal GISTs is still controversial and the relative unified guidelines and consensus opinions are inadequate. Treatment is based primarily on the clinical experience of the physician. The widespread application of neoadjuvant imatinib therapy allows diversification of treatment, especially in the choice of surgical methods. Herein, we reviewed the most recent literature and summarized the new progress in rectal tumor treatment, with the aim of providing patients with more systematic and individualized therapeutic strategies.

Transanal Endoscopic Platforms: TAMIS versus Rigid Platforms: Pros and Cons

Transanal endoscopic surgery encompasses the minimally invasive surgical techniques used to operate in the rectum under magnification while maintaining pneumorectum via a resectoscope or port. The view, magnification, and surgical precision afforded by these advanced transanal techniques have resulted in excellent specimen quality and low recurrence rates, especially compared with traditional transanal surgery. For rigid platforms, the surgeon operates through a rigid 4-cm diameter steel proctoscope of varying lengths that is clamped to the operating table with an articulating arm. Transanal minimally invasive surgery (TAMIS) is a newer flexible platform using a disposable port which "hooks" into the anorectal ring to remain in place. The cost-effectiveness and versatility of the TAMIS platform have resulted in its popularity and use in more advanced applications such as transanal total mesorectal excision. Ultimately, the choice of operating platform should be based on surgeon preference, patient characteristics, availability, and cost. The pros and cons of each platform will be discussed in this article.

Complex Procedures in Transanal Endoscopic Microsurgery: Intraperitoneal Entry, Ultra Large Rectal Tumors, High Lesions, and Resection in the Anal Canal

Transanal endoscopic microsurgery (TEM) allows the local excision of rectal tumors and achieves lower morbidity and mortality rates than total mesorectal excision. TEM can treat lesions up to 18 to 20 cm from the anal verge, obtaining good oncological results in T1 stage cancers and preserving sphincter function. TEM is technically demanding. Large lesions (>5 cm), those with high risk of perforation into the peritoneal cavity, those in the upper rectum or the rectosigmoid junction, and those in the anal canal are specially challenging. Primary suture after peritoneal perforation during TEM is safe and it does not necessarily require the creation of a protective stoma. We recommend closing the wall defect in all cases to avoid the risk of inadvertent perforation. It is important to identify these complex lesions promptly to transfer them to reference centers. This article summarizes complex procedures in TEM.

Initial clinical experience with a novel flexible endoscopic robot for transanal surgery

Background

The Flex^® Robotic System (Medrobotics, Raynham, MA, USA) is the first miniaturised flexible endoscopic robot that aims to allow surgical manoeuvres beyond the area currently reached by transanal endoscopic microsurgery. The aim of this study is to evaluate our initial clinical experience with this novel tool.

Methods

We prospectively collected all consecutive cases of local excisions of rectal lesions performed with the Flex^® Robotic System performed at the Department of Surgical Sciences of the University of Turin between October 2018 and December 2019. Indications were benign, or early rectal lesions judged unsuitable for endoscopic removal, within 20 cm of the anal verge. Debriefing meetings after each procedure allowed technology assessment leading to the modification, development, and implementation of tools according to the clinical experience. We analysed the data in terms of the safety and efficacy of treatment.

Results

Between October 2018 and February 2020, 26 patients were treated. We performed a full-thickness excision in 14 patients and a submucosal dissection in 12. The median operating time was 115 min (range 45–360 min). In six patients (23.1%), we converted to standard transanal endoscopic operation (TEO^®) (Karl Storz, Tuttlingen, Germany) to complete the procedure. The 30-day morbidity rate was 11.5% (3/26). Positive resection margins were detected in 4 (15.4%) patients. At a minimum follow-up of 12 months, 2 (7.7%) local recurrences were observed.

Conclusions

This first clinical series demonstrates that the Flex^® Robotic System is a fascinating technology that deserves further development to increase surgical dexterity, thereby overcoming current technical limitations and improving clinical outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10151-022-02577-1.

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.

Endoscopic Management of Complex Colorectal Polyps: Current Insights and Future Trends

Most colorectal cancers arise from adenomatous polyps and sessile serrated lesions. Screening colonoscopy and therapeutic polypectomy can potentially reduce colorectal cancer burden by early detection and removal of these polyps, thus decreasing colorectal cancer incidence and mortality. Most endoscopists are skilled in detecting and removing the vast majority of polyps endoscopically during a routine colonoscopy. Polyps can be considered “complex” based on size, location, morphology, underlying scar tissue, which are not amenable to removal by conventional endoscopic polypectomy techniques. They are technically more challenging to resect and carry an increased risk of complications. Most of these polyps were used to be managed by surgical intervention in the past. Rapid advancement in endoscopic resection techniques has led to a decreasing role of surgery in managing these complex polyps. These endoscopic resection techniques do require an expert in the field and advanced equipment to perform the procedure. In this review, we discuss various advanced endoscopic techniques for the management of complex polyps.

Implementation of transanal minimally invasive surgery (TAMIS) for rectal neoplasms: results from a single centre

Background

Local excisions are important in a tailored approach to treatment of rectal neoplasms. In cases of low risk T1 local excision facilitates rectal-preserving treatment. Transanal minimally invasive surgery (TAMIS) is the most recent alternative developed for local excision. In this study we evaluate the results after implementing TAMIS as the routine procedure for local excision of rectal neoplasms.

Methods

All patients who underwent TAMIS from January 2016 to January 2020 at St. Olav’s University Hospital were included, and clinical, pathological and oncological data were prospectively registered. The primary endpoint was local recurrence, and the secondary endpoint was complications.

Results

There were 76 patients (42 men, mean age was 69 years [range 26–88 years]), The mean tumour level was 82 mm (range 20–140 mm) from the anal verge measured on rigid proctoscopy, and mean tumour size was 32 mm (range 8–73 mm). Three patients experienced complications needing intervention (Clavien–Dindo > 3A). Seventeen patients had rectal adenocarcinoma, 9 of whom underwent R0 completion total mesorectal excision (cTME). Fifty-five patients had an adenoma, 3 of whom developed recurrence (5.4%) within 12 months. All recurrences were treated successfully with a new TAMIS procedure. In addition, TAMIS was used in treatment of 2 patients with a neuroendocrine tumour, 1 patient with a haemangioma and 1 patient with a solitary rectal ulcer.

Conclusions

TAMIS surgery is associated with a low risk of complications and a low recurrence rate in rectal neoplasms. In cases of adenocarcinoma, R0 cTME surgery is feasible in the sub-group with high risk T1 and T2 tumours.

Transanal Minimally-Invasive Surgery (TAMIS): Experience with No Closure of the Rectal Defect

Background In transanal minimally-invasive surgery (TAMIS), the closure of the rectal defect is controversial, and endoluminal suture is one of the most challenging aspects. The goal of the present study is to evaluate the short- and medium-term complications of a consecutive series of patients with extraperitoneal rectal injuries who underwent TAMIS without closure of the rectal defect.

Materials and Methods A prospective, longitudinal, descriptive study conducted between August 2013 and July 2019 in which all patients with extraperitoneal rectal lesions, who were operated on using the TAMIS technique, were consecutively included. The lesions were: benign lesions ≥ 3 cm; neuroendocrine tumors ≤ 2 cm; adenocarcinomas in stage T1N0; and adenocarcinomas in stage T2N0, with high surgical risk, or with the patients reluctant to undergo radical surgery, and others with doubts about complete remission after the neoadjuvant therapy. Bleeding, infectious complications, rectal stenosis, perforations, and death were evaluated.

Results A total of 35 patients were treated using TAMIS without closure of the defect. The average size of the lesions was of 3.68 ± 2.1 cm (95% confidence interval [95%CI]: 0.7 cm to 9 cm), their average distance from the anal margin was of 5.7 ± 1.48 cm, and the average operative time was of 39.2 ± 20.5 minutes, with a minimum postoperative follow-up of 1 year. As for the pathologies, they were: 15 adenomas; 3 carcinoid tumors; and 17 adenocarcinomas. In all cases, the rectal defect was left open.

The overall morbidity was of 14.2%. Two patients (grade II in the Clavien-Dindo classification) were readmitted for pain treatment, and three patients (grade III in the Clavien-Dindo classification) were assisted due to postoperative bleeding, one of whom required reoperation.

Conclusion The TAMIS technique without closure of the rectal defect yields good results, and present a high feasibility and low complication rate.

Multidisciplinary management of early rectal cancer - The role of surgical local excision in current and future clinical practice

The implementation of bowel cancer screening programs has led to a rise in the incidence of early rectal cancer. The combination of increased incidence and the growing interest in organ-sparing treatment options has led to an amplified importance of local excision techniques in treatment strategies for early rectal cancer. In addition, developments in new technologies of single-port surgery have popularized surgical techniques. Although local treatment of early rectal cancer seems promising, a multidisciplinary approach is necessary and awareness of the oncological robustness is warranted to enable shared decision-making. This review illustrates the position of surgical local excision in the treatment of early rectal cancer and reflects on its role in current and future clinical practice.

Minimally invasive gastrointestinal surgery: From past to the future

The improvement of the science and art of surgery began over 150 years ago. Surgical core tasks, “cutting and sewing” with hand and direct contact with the organs, have remained the same. However, in the 21st century, there has been a shifting paradigm in the methodology of surgery. The joint union between innovators, engineers, industry, and patient demands resulted in minimally invasive surgery (MIS). This method has influenced the techniques in every aspect of abdominal surgery, such as surgeons are not required to direct contact or see the structures on which they operate. Advances in the endoscope, imaging, and improved instrumentations convert the essential open surgery into the endoscopic method. Furthermore, computers and robotics show a promising future to facilitate complex procedures, enhance accuracy in microscale operations, and develop a simulation to improve the ability to face sophisticated approaches. MIS has been replacing open surgery due to improved survival, fewer complications, and rapid recoveries in recent years. Minimally invasive surgery's further research in diagnostic and therapeutic modalities is under investigation to achieve genuinely “noninvasive” surgery. Thus, MIS has gained interest in recent days and has been improving with promising outcomes.

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Minimally invasive surgery has interfered with multiple aspects of the surgical approach.

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Advancement in the endoscope, imaging, and other instrumentations shifting the current methodological conventional surgery.

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The benefit over risk is the promising primary outcome to achieve an exceptional quality of life.

Transanal minimally invasive surgery using laparoscopic instruments of the rectum: A review

Transanal minimally invasive surgery (TAMIS) was first described in 2010 as an alternative to transanal endoscopic microsurgery (TEM). The TAMIS technique can be access to the proximal and mid-rectum for resection of benign and early-stage malignant rectal lesions and also used for noncurative intent surgery of more advanced lesions in patients who are not candidates for radical surgery. TAMIS has a shorter learning curve, reduced device setup time, flexibility in instrument use, and versatility in application than TEM. Also, TAMIS shows similar results in a view of the operation time, conversion rate, reoperation rate, and complication to TEM. For these reasons, TAMIS is an easily accessible, technically feasible, and cost-effective alternative to TEM. Overall, TAMIS has enabled the performance of high-quality local excision of rectal lesions by many colorectal surgeons. As TAMIS becomes more broadly utilized such as pelvic abscess drainage, rectal stenosis, and treatment of anastomotic dehiscence, the acquisition of appropriate training must be ensured, and the continued assessment and assurance of outcome must be maintained.

Concepts and prospects of minimally invasive colorectal cancer surgery

It is important that clinical radiologists understand and appreciate the minimally invasive surgery (MIS) options available to surgeons. Operative technologies are constantly evolving, and accurate, informed interpretation of clinical imaging is essential for optimum surgical management. Concurrent advancements in both MIS and radiological staging have certainly improved treatment decisions and outcomes. This article outlines the history, current concepts, evolving techniques, and future prospects of MIS as it pertains to colorectal cancer surgery.

Transanal total mesorectal excision and transabdominal robotic surgery for rectal cancer: A retrospective study

BACKGROUND

Transabdominal robotic surgery and transanal total mesorectal excision (TaTME) are newly introduced strategies for rectal cancer. These procedures might have many advantages in rectal cancer treatment in terms of improving oncological and functional outcomes, especially in cases involving advanced cancer or technical difficulty. In the present study, we aimed to clarify the advantages and disadvantages of transabdominal robotic surgery and laparoscopic TaTME as a hybrid surgery for rectal cancer.

MATERIALS AND METHODS

We retrospectively evaluated six patients who underwent hybrid surgery for rectal cancer from August 2018 to April 2020. Both clinical and pathological outcomes were assessed.

RESULTS

Two patients showed circumferential margin involvement both before and after neoadjuvant therapy. Three patients were planned to undergo hybrid surgery with intersphincteric resection because of a narrow pelvis. One patient was planned to undergo hybrid surgery for a giant tumor of >10 cm. The median length of hospitalization was 17 days. No patients required conversion to an open procedure. All patients underwent formation of defunctioning ileostomies. Two patients had a stapled anastomosis and four had a hand-sewn coloanal anastomosis. Complications included one case of anastomotic leakage, which was managed conservatively with ultrasound- and computed tomography-guided drainage and antibiotics. Histological analysis revealed that all specimens had a negative radial margin and distal margin. The median number of lymph nodes harvested was 17.5. Two patients showed extensive lymph node metastases, including lateral node metastasis.

CONCLUSION

Hybrid surgery was performed safely and may improve oncological outcomes for rectal cancer. This technique has many potential benefits and would be alternative option in multimodal strategies for rectal cancer.

Transanal minimal invasive surgery (TAMIS): safety and feasibility for the resection of benign and malignant lesions of the rectum

Objectives

Radical surgery for rectal tumours has high morbidity. Local excision of such tumours can be achieved without compromising oncologic safety. However tumours that are not accessible to local excision can be approached using Transanal Minimal Invasive Surgery (TAMIS). The aim of our study was to assess feasibility of TAMIS procedure in terms of complications, operating time, resection margin positivity, hospital stay and local recurrence rate.

Material and Methods

Forty eight patients with benign adenomas or early stage adenocarcinoma, within 4 to 12 cm from anal verge who were subjected to TAMIS over a period of 3 years were included in the study. Short and long term outcomes were assessed.

Results

TAMIS was performed for 36 benign adenomas and 12 adenocarcinomas, which were located at an average distance of 6.2 cm from anal verge. The mean operating time was 72 minutes. There were no intraoperative complications.1 (2.08%) patient suffered post operative bleeding, which was managed conservatively. 2 (4.16%) patients developed acute urinary retention who required indwelling catheterisation. Resection margin was positive in 3 (6.25%) benign cases. Average hospital stay was 2.7 days. Local recurrence occurred in 2 (4.16%) villous adenoma patients (after 11 and 13 months), whereas in malignant patients there was no recurrence at a follow up period ranging between 12 to 36 months.

Conclusion

TAMIS is a safe and feasible procedure for benign tumours and early rectal cancers, located in low and middle rectum.

Robotic Transanal Surgery for Rectal Cancer

Robotic transanal surgery is the culmination of major developments in rectal cancer management and minimally invasive surgery. It is the result of continuous efforts to tackle the challenges inherent to rectal cancer surgery. This latest technology holds great promise and excitement for the care of the rectal cancer patient. In this article, we will describe the evolution of transanal rectal cancer surgery and describe how the convergence of transanal transabdominal, transanal endoscopic microsurgery, transanal minimally invasive surgery (TAMIS), transanal total mesorectal excision (taTME), and the different robotic platforms have culminated in the development of single port robotic transanal minimally invasive surgery (SP rTAMIS) and single port robotic transanal total mesorectal excision (SP rtaTME). We will describe the indications, technical aspects, outcomes, benefits, and limitations of the SP rTAMIS and SP rtaTME.

Robotic transanal total mesorectal excision: Is the future now?

Total mesorectal excision (TME) is the standard surgical treatment for the curative radical resection of rectal cancers. Minimally invasive TME has been gaining ground favored by the continuous technological advancements. New procedures, such as transanal TME (TaTME), have been introduced to overcome some technical limitations, especially in low rectal tumors, obese patients, and/or narrow pelvis. The earliest TaTME reports showed promising results when compared with the conventional laparoscopic TME. However, recent publications raised concerns regarding the high rates of anastomotic leaks or local recurrences observed in national series. Robotic TaTME (R-TaTME) has been proposed as a novel technique incorporating the potential benefits of a perineal dissection together with precise control of the distal margins, and also offers all those advantages provided by the robotic technology in terms of improved precision and dexterity. Encouraging short-term results have been reported for R-TaTME, but further studies are needed to assess the real role of the new technique in the long-term oncological or functional outcomes. The present review aims to provide a general overview of R-TaTME by analyzing the body of the available literature, with a special focus on the potential benefits, harms, and future perspectives for this novel approach.

First Clinical Experience With Single-Port Robotic Transanal Minimally Invasive Surgery: Phase II Trial of the Initial 26 Cases

BACKGROUND

Many transanal platforms have been developed to address the challenge of reach and vision when operating transanally. The single-port robot was specifically designed for narrow-aperture surgery and is a promising platform for minimally invasive transanal surgery.

OBJECTIVE

The purpose of this phase II trial is to evaluate the safety and feasibility of the initial clinical experience with single-port robot transanal minimally invasive surgery.

DESIGN

In a prospective phase II trial, patients with rectal neoplasms eligible for local excision were enrolled for single-port robotic transanal minimally invasive surgery.

SETTING

The study was conducted between October 2018 and March 2020 at a tertiary referral hospital.

PATIENTS/INTERVENTION

Twenty-six consecutive patients underwent single-port robotic transanal minimally invasive surgery resection of rectal lesions.

MAIN OUTCOME MEASURES

The primary end point of the study was the efficacy and safety of single-port robotic transanal minimally invasive surgery.

RESULTS

There were 13 men and 13 women, with an average lesion size of 2.9 cm (range, 1.0-6.0 cm) and average level of 4.8 cm from the anorectal ring (range, 0-30 cm). Ten patients had a preoperative diagnosis of adenocarcinoma, 7 of whom received neoadjuvant chemoradiation (range, 4500-5580 cGy with concurrent oral capecitabine). Eighty-eight percent of cases were completed by single-port robotic transanal minimally invasive surgery; 2 were converted to transanal endoscopic microsurgery, and 1 patient underwent a low anterior resection. There were no piecemeal extractions, and all margins were negative on final pathology. There were no mortalities, and the morbidity rate was 15.4%. There have been no local recurrences, with a mean follow-up of 5.8 months (range, 0-15.9 months).

LIMITATIONS

The study was limited by small sample size, short-term follow up, and a single-surgeon experience.

CONCLUSION

Single-port robotic transanal minimally invasive surgery procedures are safe and feasible in patients with select benign and malignant rectal lesions. Future trials will need to evaluate the long-term safety and efficacy of single-port robotic transanal minimally invasive surgery. See Video Abstract at http://links.lww.com/DCR/B605.

PRIMERA EXPERIENCIA CLNICA CON CIRUGA MNIMAMENTE INVASIVA TRANSANAL ROBTICA DE PUERTO NICO ENSAYO DE FASE II DE LOS CASOS INICIALES

ANTECEDENTES:Se han desarrollado muchas plataformas transanales para abordar el desafío del alcance y la visión cuando se opera de manera transanal. El robot de un solo puerto fue diseñado específicamente para la cirugía de apertura estrecha y es una plataforma prometedora para la cirugía transanal mínimamente invasiva.OBJETIVO:El propósito de este ensayo de fase II es evaluar la seguridad y viabilidad de la experiencia clínica inicial con la cirugía mínimamente invasiva transanal con robot de puerto único.DISEÑO:En un ensayo prospectivo de fase II, los pacientes con neoplasias rectales elegibles para la escisión local se inscribieron para la cirugía mínimamente invasiva transanal robótica de puerto único.AJUSTE:El estudio se realizó entre octubre de 2018 y marzo de 2020 en un hospital de referencia terciario.PACIENTES / INTERVENCIÓN:Veintiséis pacientes consecutivos fueron sometidos a cirugía mínimamente invasiva transanal robótica de puerto único para resección de lesiones rectales.PRINCIPALES MEDIDAS DE RESULTADO:El criterio de valoración principal del estudio fue la eficacia y seguridad de la cirugía mínimamente invasiva transanal robótica de puerto único.RESULTADOS:Hubo 13 hombres y 13 mujeres, con un tamaño de lesión promedio de 2.9 cm (rango 1.0-6.0 cm) y un nivel promedio de 4.8 cm del anillo anorrectal (rango 0-30 cm). Diez pacientes tenían un diagnóstico preoperatorio de adenocarcinoma, 7 de los cuales recibieron quimiorradiación neoadyuvante (rango 4500-5580 cGy con capecitabina oral concurrente). El 88% de los casos se completaron mediante cirugía mínimamente invasiva transanal robótica de puerto único; 2 se convirtieron a microcirugía endoscópica transanal y 1 se sometió a una resección anterior baja. No hubo extracciones parciales y todos los márgenes fueron negativos en la patología final. No hubo mortalidad y una tasa de morbilidad del 15,4%. No ha habido recidivas locales, con un seguimiento medio de 5,8 meses (rango 0-15,9 meses).LIMITACIONES:El estudio estuvo limitado por un tamaño de muestra pequeño, un seguimiento a corto plazo y la experiencia de un solo cirujano.CONCLUSIÓN:Los procedimientos de cirugía mínimamente invasiva transanal robótica de puerto único son seguros y factibles en pacientes con lesiones rectales benignas y malignas seleccionadas. Los ensayos futuros deberán evaluar la seguridad y eficacia a largo plazo de la cirugía mínimamente invasiva transanal robótica de puerto único. Consulte Video Resumen en http://links.lww.com/DCR/B605. (Traducción-Dr. Eduardo Londoño-Schimmer).

Management of early rectal cancer; current surgical options and future direction

Rectal cancer is the second commonest cause of cancer death within the United Kingdom. Utilization of national screening programmes have resulted in a greater proportion of patients presenting with early-stage disease. The technique of transanal endoscopic microsurgery was first described in 1984 following which further options for local excision have emerged with transanal endoscopic operation and, more recently, transanal minimally invasive surgery. Owing to the risks of local recurrence, the current role of minimally invasive techniques for local excision in the management of rectal cancer is limited to the treatment of pre-invasive disease and low risk early-stage rectal cancer (T1N0M0 disease). The roles of chemotherapy and radiotherapy for the management of early rectal cancer are yet to be fully established. However, results of high-quality research such as the GRECCAR II, TESAR and STAR-TREC randomised control trials may highlight a wider role for local excision surgery in the future, when used in combination with oncological therapies. The aim of our review is to provide an overview in the current management of early rectal cancer, the surgical options available for local excision and the future multimodal direction of early rectal cancer treatment.

Postoperative complications of colorectal cancer

Colorectal cancer is the third most common cancer, and surgery is the most common treatment. Several surgical options are available, but each is associated with a range of potential complications. The timely and efficient identification of these complications is vital for effective clinical management of these patients in order to minimise their morbidity and mortality. This review aims to describe the range of commonly performed surgical treatments for colorectal surgery. In addition, frequent post-surgical complications are explored with investigative options explained and illustrated.

How to Learn a Complex Endoscopic Procedure: Knots in Transanal Endoscopic Surgery: Different Skill Among Surgeons

PURPOSE

The intrarectal suture is considered a high technically complex procedure. The study's objectives were to assess the feasibility of making an intrarectal knot, through an in vitro study and assessing whether the video tutorial facilitates learning.

MATERIALS AND METHODS

A detailed description of the technique. A comparative observational cross-sectional study in surgeons with no previous experience in intrarectal knots.

RESULTS

Twenty-one of these 32 participants passed the intrarectal knot test without video tutorial (T1) (65.6%), and 26 (81.2%) after the video tutorial (T2) (P=0.26). The mean time taken to tie the knot fell from 74 seconds (SD=46) in T1 to 41 seconds (SD=41) in T2 (P<0.001). At T1, 26 participants (81.3%) described the technique as difficult, but only 7 (21.9%) at T2 (P<0.001).

CONCLUSIONS

Performing the intrarectal knot suture is feasible. Despite the technical difficulty, the video tutorial is sufficient for surgeons to learn the technique.

Envisioning the future of colorectal surgery: preclinical assessment and detailed description of an endoluminal robotic system (ColubrisMX ELS)

BACKGROUND

The EndoLuminal Surgical System (ELS) is an emerging non-linear robotic system specifically designed for transanal surgery that allows for excision of colorectal neoplasia and luminal defect closure.

METHODS

An evaluation of ELS was conducted by a single surgeon in a preclinical setting at the EndoSurgical Center of Florida in Orlando, between October 1st, 2020 and December 31st, 2020, using porcine colon as a model. Mock lesions measured 2.5 to 3.5 cm were excised partial-thickness. Specimen quality and excision time was assessed and evaluated.

RESULTS

Twenty consecutive robotic transanal minimally invasive surgery (TAMIS) operations utilizing the ELS system were successfully performed without fragmentation. The mean and standard deviation procedure time for all 20 cases was 18.41 ± 14.15 min. The latter 10 cases were completed in substantially less time, suggesting that ELS requires at least 10 preclinical cases for a surgeon to become familiar with the technology. A second task, namely suture closure of the partial-thickness defect, was performed in 9 of the 20 cases. Mean time and standard deviation for this task measured 27.89 ± 10.07 min. There were no adverse events.

CONCLUSIONS

ELS was successful in performing the tasks of partial-thickness disc excision and closure in a preclinical evaluation. Further study is necessary to determine its clinical applicability.

Robotic Transanal Total Mesorectal Excision (RTaTME): State of the Art

Total mesorectal excision (TME) is the gold standard technique for the surgical management of rectal cancer. The transanal approach to the mesorectum was introduced to overcome the technical difficulties related to the distal rectal dissection. Since its inception, interest in transanal mesorectal excision has grown exponentially and it appears that the benefits are maximal in patients with mid-low rectal cancer where anatomical and pathological features represent the greatest challenges. Current evidence demonstrates that this approach is safe and feasible, with oncological and functional outcome comparable to conventional approaches, but with specific complications related to the technique. Robotics might potentially simplify the technical steps of distal rectal dissection, with a shorter learning curve compared to the laparoscopic transanal approach, but with higher costs. The objective of this review is to critically analyze the available literature concerning robotic transanal TME in order to define its role in the management of rectal cancer and to depict future perspectives in this field of research.

Robotic TAMIS: A Technical Note Comparing Si® versus Xi®

Transanal minimally invasive surgery (TAMIS) can be performed robotically assisted (R-TAMIS) for easier rectal defect suture closure particularly on the anterior rectal wall. The surgical technique described in this technical note emphasizes three safety points: 1) decreased likelihood for rectal injury when the ports are inserted into the GelPOINT® Path Transanal Access Platform (Applied Medical, Rancho Santa Margarita, California) on the back table rather than being inserted into the rectum; 2) decreased external collision between ports when using ports of different length; and 3) increased stabilization of pneumorectum when insufflating with an AirSeal™ port (Intelligent Flow System, ConMed, Utica, New York). Although R-TAMIS can be safely performed with the da Vinci® Si® or Xi® (Intuitive Surgical Inc., Sunnyvale, California) patient cart, the following differences are noteworthy: a) the Si® vertically-mounted arms design forces the patient in an uncomfortable position with asymmetrical hip flexion as opposed to the Xi® boom-mounted horizontal arm design; b) the 28cm circumference of each Si® patient cart arms operating between the patient's legs offer decreased maneuvering freedom as opposed to the 19cm circumference of the Xi® counterparts; and c) the abduction pattern of movement of the Si® arms potentially increases the risk of external collision with the patient's legs as opposed to the Xi® "jack-knife" pattern of movement.

Transanal endoscopic surgery with a 3D printed device

BACKGROUND

The aim of this study was to investigate the effectiveness of devices manufactured with 3D printing for performing transanal endoscopic procedures without pneumorectum.

METHODS

Functional devices were designed in the Polytechnic School of Engineering of Gijón from 2016 to 2018 using three-dimensional (3D) solid modelling software (Solid-Works®), that allows customization of the device (diameter and length). The devices were made in acrylonitrile butadiene styrene (ABS) by additive manufacturing using an HP Designjet 3D Printer, with fused deposition modelling (FDM) technology. Tests were carried out on mixed simulators (with viscera) and cadavers with a prototype in the form of an open cylindrical base ellipsoid spindle with two bars. In this paper, we present the information of the first series of patients in which this device has been used to perform a full-thikness endoscopic resection of the rectal wall without pneumorectum. The characteristics of the patients, size, and location of the lesion, the type of anesthesia used, the duration of the procedure, hospital stay, complications, and pathology were analyzed. An endoscopic follow-up was also carried out for at least 2 years.

RESULTS

Seven interventions were carried out in six patients. The lesions were located at a mean distance of 5 cm from the anal verge and an average area of 11.8 cm². Four of the procedures were performed with general anesthesia and 3 with spinal anesthesia. Histopathology examination identified 3 adenomas, 3 pT1 and 1 pT2 adenocarcinomas. All excisions were full thickness. En bloc excision was possible in all cases. In only one case of a benign polyp there was a positive lateral margin. As regards complications, there was one case of postoperative rectal bleeding without the need for transfusions. There were no readmissions and no postoperative mortality.

CONCLUSIONS

An innovative device made with a 3D printer can be used successfully in transanal endoscopic resections of the rectal wall, with spinal anaesthesia and avoiding the need for pneumorectum.

SP rTaTME: initial clinical experience with single-port robotic transanal total mesorectal excision (SP rTaTME)

BACKGROUND

The technical difficulty and steep learning curve of transanal total mesorectal excision (taTME) has limited widespread adoption. The single-port (SP) daVinci robot is designed to facilitate single-incision and natural-orifice transluminal endoscopic surgery (NOTES). This paper describes the first clinical experience of single-port robotic taTME (SP rTaTME).

METHODS

This was a prospective study on consecutive patients with rectal cancer who underwent SP rTaTME proctosigmoidectomy with handsewn coloanal anastomosis in December 2018 and January 2019. The primary outcome was technical feasibility of the procedure. The secondary outcomes include blood loss, intraoperative complications, length of hospital stay, quality of the TME specimen, short- and long-term morbidity and mortality, as well as short-term oncologic follow -up.

RESULTS

There were two patients, a 48-year-old male and a 38-year-old female. Both operations were completed successfully without complications or conversion. Estimated blood loss was 200 mL and 130 mL. In both cases the TME was completed transanally using the SP robot. In the first patient, the abdominal portion was completed through an abdominal single-incision; in the second patient the operation was entirely performed transanally as a pure NOTES procedure. In both cases, the final pathology report showed a complete TME with negative margins. Patients were discharged on postoperative day 3 and 4,respectively. There was no long-term morbidity or mortality.

CONCLUSIONS

SP rTaTME is feasible and can be safely performed. It provides excellent optics and dexterity to work in a limited space. Future studies are required to further define the safety profile and the ultimate utility of the SP robot for taTME.

Trans-anal minimally invasive surgery (TAMIS) versus trans-anal endoscopic microsurgery (TEM): a comparative case-control matched-pairs analysis

AIM

Since its introduction, transanal endoscopic microsurgery (TEM) has become the treatment of choice for rectal benign lesions not amenable to flexible endoscopic excision and for early rectal cancer. Disposable soft devices as the Trans-anal Minimally Invasive Surgery (TAMIS) are a valid alternative to non-disposable rigid trans-anal endoscopic microsurgery (TEM) platforms. The aim of the present study is to compare TEM and TAMIS in terms of incidence of R1 resection and lesion fragmentation which were combined in a composite outcome called quality resection. Perioperative complication and operative time were also investigated.

METHODS

A total of 132 patients were eligible for this study of whom 63 (47.7%) underwent TAMIS and 69 (52.3%) underwent TEM. Patients were extracted for from a prospective maintained database and groups resulted homogenous after matching using propensity score in terms of size of the lesion, height from the anal verge, position within the rectal lumen, preoperative histology, neoadjuvant treatment. A multivariate logistic and linear regression analysis was carried out using those variables that have significant independent relationship with the quality of surgical resection and operative time.

RESULTS

The incidence of R0 resection and lesion fragmentation was similar between groups. No differences were found in terms of perioperative complication. TAMIS was associated with less setup time and less operative time compared with TEM. Variables influencing quality resection at the multivariate analysis were larger lesion (> 5 cm) and ≥ T2 stage. Variables influencing operative time were surgical procedure (TEM vs TAMIS), height from the anal verge and size of the lesion.

CONCLUSION

The present study shows that TEM and TAMIS are equally effective in terms of quality of local excision and perioperative complication. TAMIS resulted less operative time consuming compared to TEM.

Short-term outcomes after transanal total mesorectal excision for rectal cancer in Denmark - a prospective multicentre study

AIM

The aim of this study was to evaluate the short-term surgical and oncological outcomes after transanal total mesorectal excision (TaTME) for rectal cancer during the implementation phase of this procedure in Denmark.

METHOD

This is a retrospective review of prospectively recorded data. Registration was initiated by the Scientific Council of the Danish Colorectal Cancer Group (DCCG.dk) in order to assess the quality of care during the implementation of TaTME. Pre-, intra- and postoperative data including early recurrences were recorded at the operating centres.

RESULTS

From August 2016 to April 2019, 115 TaTME procedures were registered. Patients were predominantly male (74%) with mid-rectal (88%) tumours. The level of surgical complications was comparable to previous nationwide results. Anastomotic leakage occurred in 6/109 (5.5%). One urethral injury occurred. The plane of dissection was mesorectal in 60% of cases, intramesorectal in 28% and muscularis in 12%. Nonmicroradicality was seen in 8% (R1, 6%; R2, 2%). Four local recurrences occurred after a median of 23 months of follow-up. One of these was multifocal.

CONCLUSION

In an implementation phase where patient selection is expected, surgical and oncological results after TaTME were comparable to those of other approaches reported in the literature.

Beyond transanal total mesorectal excision: short-term outcomes of transanal total mesorectal excision in locally advanced rectal cancer requiring resection beyond total mesorectal excision

AIM

The aim of this work was to define the role of transanal total mesorectal excision (taTME) in locally advanced rectal cancer (LARC) requiring resection beyond the mesorectal plane.

METHOD

We performed a retrospective review of the outcomes of a case series of patients undergoing taTME for rectal cancer with mesorectal fascia or adjacent organ involvement.

RESULTS

Eleven patients (six men) underwent taTME for LARC requiring resection beyond total mesorectal excision (TME). All had a restorative procedure. The transabdominal approach was open in five and minimally invasive in six cases. All patients required the resection of at least one adjacent structure, including presacral fascia, internal iliac vessels, nerve roots, uterus, vagina or seminal vesicles. Four patients required a pelvic side-wall lymph node dissection and four had intraoperative radiotherapy. In all cases, the transanal approach was useful to disconnect the rectum distally, resect adjacent organs or control the R1 risk-point. Three patients had a complication of Clavien-Dindo grade III or above (one mechanical bowel obstruction, one pelvic collection and one urine sepsis). There were no anastomotic complications. Ten patients had an R0 resection. During a median follow-up of 11 (8.6-16) months there were no local recurrences, but two patients had distant metastases. During the study period, eight patients underwent closure of their stoma whilst the remaining three have had normal anastomotic assessments and will be closed in the future.

CONCLUSION

This early series shows that implementation of taTME for resections beyond TME may be feasible and safe in a highly selected 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.

Transanal minimally invasive surgery (TAMIS) for local excision of selected rectal neoplasms: efficacy and outcomes in the first 11 patients

Disposable single-port surgery devices have been used for transanal minimally invasive surgery (TAMIS) with benefits, when compared to local resection and transanal endoscopic microsurgery (TEM).

Objective To show outcomes and details of the technique.

Method A series of patients with indication for local resection of rectal tumors were submitted to surgery using the TAMIS platform.

Results Eleven patients have been submitted to TAMIS. Distance from anal verge was from 1.5 to 8 cm and maximum tumor diameter was 6 cm. Initial diagnosis of adenoma was the most frequent indication for resection. One partial dehiscence was the only complication seen. Minimal setup time, low cost and the possibility of using regular laparoscopic instruments make TAMIS a good option for transanal resection. The results of this technique are encouraging, concerning the feasibility, maneuverability, upfront cost, setup time, resectability and complication rate. Because of its simplicity and similarity with conventional laparoscopic surgery, it can be learned easily. Although at the present time the appropriate use of local excision is still under debate, TAMIS is a technique that still expects a lot of growing and much remains to be learned.

Transanal minimally-invasive surgery (TAMIS): Technique and results from an initial experience

Transanal endoscopic microsurgery is a minimally-invasive approach for rectal lesions. Superior exposure and access to the entire rectum result in lesser risk of compromised margins and lower recurrence rates, when compared to conventional transanal excision. The aim of this study was to describe a single institution's initial experience with transanal minimally invasive surgery (TAMIS). This was a prospective review of our database. Eleven procedures from January 2012 to June 2013 were analyzed.

Results eleven operations were completed. Five men were evaluated. Mean age was 62.9 (40-86). Mean follow-up was 9.3 (2-17) months. Average tumor size was 3.8 (1.8-8) cm. Mean distance from anal verge was 6.3 (3-12) cm. Mean operating time was 53.73 (28-118) min. Postoperative complication rate was 9.1%. There were no readmissions. Mortality was null. Operative pathology disclosed the presence of adenoma in four patients, invasive adenocarcinoma in two, neuroendocrine carcinoma in three, and no residual lesion in one case. TAMIS is a minimallyinvasive procedure with low postoperative morbidity at the initial experience. TAMIS is a curative procedure for benign lesions and for selected early cancers. It is useful after neoadjuvant therapy for strictly selected cancers, pending the results of multi-institutional trials.