Preclinical cadaveric study of transanal endoscopic da Vinci® surgery

Development of a mechanical decoupling surgical scissors for robot-assisted minimally invasive surgery

In minimally invasive surgery, surgical instruments with a wrist joint have better flexibility. However, the bending motion of the wrist joint causes a coupling motion between the end-effector and wrist joint, affecting the accuracy of the movement of the surgical instrument. Aiming at this problem, a new gear train decoupling method is proposed in the paper, which can automatically compensate for the coupled motion in real-time. Based on the performance tests of the instrument prototype, a series of decoupling effects tests are carried out. The test results show that the surgical instrument has excellent decoupling ability and stable performance.

Robotic transanal minimally invasive surgery - technical, oncological and patient outcomes from a single institution

AIM

Robotic transanal minimally invasive surgery (R-TAMIS) is gaining traction around the globe as an alternative to laparoscopic conventional TAMIS for local excision of benign and early malignant rectal lesions. The aim was to analyse patient and oncological outcomes of R-TAMIS for consecutive cases in a single centre.

METHODS

A prospective analysis of consecutive R-TAMIS procedures over a 12-month period was performed. Data were collated from hospital databases and theatre registers.

RESULTS

Eleven patients (six men, five women), mean age 69.81 years (51-92 years), underwent R-TAMIS over 12 months utilizing a da Vinci Xi platform. The mean lesion size was 36 mm (20-60 mm) with a mean distance from the anal verge of 7.5 cm (3-14 cm). Five lesions were posterior in anatomical location, four anterior, one right lateral and one left lateral. All procedures were performed in the lithotomy position using a GelPOINT Path Platform. Mean operative time was 64 min (40-100 min). Complete resection was achieved in 10/11 patients with two patients being upgraded to a diagnosis of adenocarcinoma. Nine patients were diagnosed with dysplastic lesions. Four patients had a false positive diagnosis of an invasive tumour on MRI. Six patients required suturing for full-thickness resections. One patient had a postoperative bleed requiring repeat endoscopy and clipping. One patient (full-thickness resection of T3 tumour) proceeded to a formal resection without difficulty with no residual disease (T0N0, 0/22). One patient with a fully resected T2 tumour is undergoing a surveillance protocol. The mean length of stay was 1 day with two patients having a length of stay of 2 days and one patient of 4 days.

CONCLUSION

R-TAMIS could potentially represent a safe novel approach for local resection of rectal lesions.

Future Directions

Transanal total mesorectal excision (taTME) is a novel technique that has evolved over the years to address the challenges of low rectal cancer surgery by applying the principles and benefits of laparoscopic surgery to more historic transanal techniques. It has been popularized through its use in rectal cancer, but the transanal approach is slowly being expanded to tackle different clinical scenarios including benign conditions such as inflammatory bowel disease and endometriosis. For all of these new indications, it is the desire to access and begin the dissection in native tissue beyond the pathology which makes this approach applicable to other diseases where anatomy can be challenging. Training pathways to safely introduce taTME in a standardized manner are being developed and implemented in a bid to ensure adequate training to all the surgeons using this technique and thus minimize complications and patient morbidity. The future directions of this promising technique include the use of image and optical technological enhancement to aid navigation, the use of pneumorectum stabilization, and perhaps the use of fluorescence as a safety improvement. Developments have come also from the field of robotics. After a demonstration of feasibility in cadaver models, a growing experience has been gathered in the robotic approach to taTME, covered in the last part of this chapter.

The outcomes of two robotic platforms performing transanal minimally invasive surgery for rectal neoplasia: a case series of 21 patients

Colorectal cancer remains the third most common cancer effecting adults. Surgical guidelines recommend transanal excision of early rectal neoplasia up to 8 cm from the anal verge. A retrospective review of two novel approaches for transanal robotic local excision with R0 resections of rectal cancers which was, on average, higher than 8 cm. Twenty-one cases of robotic assisted transanal surgery for early stage disease (T0-T1, N0) were reviewed. The first 10 cases performed with the da Vinci^® Si robotic platform between 2013 and 2016, and the first 11 cases performed using the Flex^® Medrobotics platform between August 2017 and August 2018. The average distance from the anal verge was 11.1 cm and 9.5 cm for the da Vinci^® Si and Flex^® Colorectal Drive, respectively. The average operative time was 167.6 min for the da Vinci^® Si and 110.1 min for the Flex^® Colorectal Drive; the average EBL was 37.5 cc and 9.1 cc for the da Vinci^® Si and Flex^® Colorectal Drive. In the da Vinci^® series, four cases required intraoperative conversion. In the Flex^® series, one case was aborted due to unfavorable robotic positioning. All margins were histologically negative when surgically complete with no recurrences to date. Transanal robotic surgery may provide a method to address rectal lesions farther from the anal verge than previously described. The Flex^® Colorectal Drive platform may provide superior ability to navigate the nonlinear anatomy of the rectum and distal sigmoid colon.

Neoadjuvant radiotherapy for rectal cancer management

Thirty per cent of all colorectal tumours develop in the rectum. The location of the rectum within the bony pelvis and its proximity to vital structures presents significant therapeutic challenges when considering neoadjuvant options and surgical interventions. Most patients with early rectal cancer can be adequately managed by surgery alone. However, a significant proportion of patients with rectal cancer present with locally advanced disease and will potentially benefit from down staging prior to surgery. Neoadjuvant therapy involves a variety of options including radiotherapy, chemotherapy used alone or in combination. Neoadjuvant radiotherapy in rectal cancer has been shown to be effective in reducing tumour burden in advance of curative surgery. The gold standard surgical rectal cancer management aims to achieve surgical removal of the tumour and all draining lymph nodes, within an intact mesorectal package, in order to minimise local recurrence. It is critically important that all rectal cancer cases are discussed at a multidisciplinary meeting represented by all relevant specialties. Pre-operative staging including CT thorax, abdomen, pelvis to assess for distal disease and magnetic resonance imaging to assess local involvement is essential. Staging radiology and MDT discussion are integral in identifying patients who require neoadjuvant radiotherapy. While Neoadjuvant radiotherapy is potentially beneficial it may also result in morbidity and thus should be reserved for those patients who are at a high risk of local failure, which includes patients with nodal involvement, extramural venous invasion and threatened circumferential margin. The aim of this review is to discuss the role of neoadjuvant radiotherapy in the management of rectal cancer.

Robotic transanal microsurgery for high early rectal neoplasia (T0-T1, N0 lesions), case series of 10 patients

PURPOSE/BACKGROUND

In 2017, an estimated 39 910 people will receive a new diagnosis of rectal cancer. Current surgical guidelines limit transanal excision of early rectal neoplasia to 8 cm from the anal verge. We report that R0 resection of higher rectal cancers is possible using transanal robotic microsurgery.

METHODS/INTERVENTIONS

Ten cases of robotic assisted transanal surgery for early stage disease (T0-T1, N0) between 2013 and 2016 were reviewed.

RESULTS/OUTCOMES

All cases were diagnosed preoperatively with colonoscopy, and the average distance from the anal verge was 11.1 cm. The average operative time was 167 minutes, and the average blood loss was 37.5 cc. Four cases required intraoperative conversion; one conversion required robotic abdominal access to repair a proctotomy. All margins were histologically negative, and 6-month follow-up showed no recurrences.

CONCLUSION/DISCUSSION

Transanal robotic surgery may provide the colorectal surgeon a method to address rectal lesions farther from the anal verge.

Robotic transanal minimally invasive surgery (TAMIS) with the newest robotic surgical platform: a multi-institutional North American experience

BACKGROUND

Transanal minimally invasive surgery (TAMIS) offers intra-luminal full-thickness excision of rectal neoplasia. Robotic TAMIS (RT) allows for greater versatility in motion while operating in the limited space of the rectum. We present our experience with this technique in practice using the DaVinci Xi™ platform.

METHOD

This is a multi-institutional retrospective analysis for patient undergoing Robotic TAMIS for resection of rectal lesions at two tertiary referral hospitals in the United States. Morbidity, mortality, anatomic measurement, and final pathology were analyzed.

RESULTS

Thirty-four patients planned for Robotic TAMIS were identified. Average follow-up was 188 days. The average BMI was 29.5 ± 5.9. All patients had an American Society of Anesthesiologist (ASA) Class of 2 or greater and 21 (62%) were ASA 3 or greater. Rectal lesions located from 2 to 15 cm from the dentate line were successfully resected. Lesions up to 4.5 cm in the longest dimension were successfully resected. The average operative time was 100 ± 70 min, which correlated to a robotic console time of 76 ± 67 min. Patients were placed in Lithotomy in 32 (94%) cases and were prone in only 2 (6%) cases. There were no intraoperative complications or conversions to another technique. The only postoperative complication was a medically managed Clostridium difficile infection in 1 patient. Three patients were upstaged to T2 on final pathology and underwent successful formal resections. BMI was a statistically significant predictor of a longer operation.

CONCLUSIONS

With increased reach and operative range of motion, Robotic TAMIS is a safe and effective method for excising low-risk rectal neoplasia with a wide range of anatomical measurements. Higher BMI is a significant predictor of a longer and likely more challenging operation.

Robotic Assisted Transanal Polypectomies: Is There Any Indication?

OBJECTIVES

Robotic assisted transanal polipectomy may have advantages compared with the conventional transanal minimally invasive surgery technique. We evaluate the safety, feasibility and advantages of this technique.

METHODS

Between February 2014 and October 2015, 9patients underwent robotic transanal polypectomy. We performed a retrospective study in which we analyse prospectively collected data regarding patient and tumor characteristics, perioperative outcomes, pathological report, morbidity and mortality.

RESULTS

A total of 5 male and 4 female patients underwent robotic TAMIS. Lesions were 6,22cm from the anal verge. Mean size was 15,8cm². All procedures were performed in the lithotomy position. Closure of the defect was performed in all cases. Mean blood loss was 39,8ml. Mean operative time was 71,9min. No severe postoperative complications or readmissions occured. Median hospital stay was 2,5 days.

CONCLUSIONS

Robotic TAMIS is useful to treat complex rectal lesions. Our transanal platform allowed a wider range of movements of the robotic arms and to perform all procedures in the lithotomy position.

Shifting Paradigms in Minimally Invasive Surgery: Applications of Transanal Natural Orifice Transluminal Endoscopic Surgery in Colorectal Surgery

Since the advent of laparoscopy, minimally invasive techniques such as single port laparoscopy, robotics, endoscopically assisted laparoscopy, and transanal endoscopic surgery continue to revolutionize the field of colorectal surgery. Transanal natural orifice transluminal endoscopic surgery (NOTES) represents a further paradigm shift by combining the advantages of these earlier techniques to reduce the size and number of abdominal incisions and potentially optimize rectal dissection, especially with respect to performance of an oncologically adequate total mesorectal excision (TME) for rectal cancer. Since the first experimental report of transanal rectosigmoid resection in 2007, the potential impact of transanal NOTES in colorectal surgery has been extensively investigated in experimental models and recently transitioned to clinical application. There have been 14 clinical trials of transanal TME (taTME) for rectal cancer that have demonstrated the feasibility and preliminary oncologic safety of this approach in carefully selected patients, with results comparable to outcomes after laparoscopic and open TME, including cumulative intraoperative and postoperative complication rates of 5.5 and 35.5%, respectively, 97.3% rate of complete or near-complete specimens, and 93.6% rate of negative margins. Transanal NOTES has also been safely applied to proctectomy and colectomy for benign indications. The consensus among published series suggests that taTME is most safely performed with transabdominal assistance by surgeons experienced with laparoscopic TME, transanal endoscopic surgery, and sphincter-preserving techniques including intersphincteric resection. Future applications of transanal NOTES may include evolution to a pure endoscopic transanal approach for TME, colectomy, and sentinel lymph node biopsy for rectal cancer, with a potential role for robotic assistance.

Robotic transanal surgery for local excision of rectal neoplasia, transanal total mesorectal excision, and repair of complex fistulae: clinical experience with the first 18 cases at a single institution

BACKGROUND

Robotic transanal surgery represents a natural evolution of transanal minimally invasive surgery. This new approach to rectal surgery provides the ability to perform local excision of rectal neoplasia with precision. Robotic transanal surgery can also be used to perform more advanced procedures including repair of complex fistulae and transanal total mesorectal excision.

METHODS

Data from patients who underwent transanal robotic surgery over a 33-month period were retrospectively reviewed. Patients underwent three types of procedures using this approach: (a) local excision of rectal neoplasia, (b) transanal total mesorectal excision, and (c) closure of complex fistulae, such as rectourethral fistulae.

RESULTS

Eighteen patients underwent robotic transanal surgery during the 33-month study period. Of these, nine patients underwent local excision of rectal neoplasia; four patients underwent transanal total mesorectal excision; four patients underwent repair of rectourethral fistulae; and one patient underwent repair of an anastomotic fistula. Of the patients undergoing robotic transanal surgery for local excision, 6/9 were resections of benign neoplasia, while 3/9 were resections for invasive adenocarcinoma. There was no fragmentation (0/9) noted on any of the locally excised specimens, while one patient (1/9) had a positive lateral margin. During the mean follow-up of 11.4 months, no recurrence was detected. Four patients underwent robotic-assisted transanal total mesorectal excision for curative intent resection of rectal cancer confined to the distal rectum. Mesorectal quality was graded as complete or near complete, and an R0 resection was performed in all four cases. Other transanal robotic procedures performed were the repair of rectourethral fistulae (n = 3) and anastomotic fistula (n = 1). This approach was met with limited success, and only half of the rectourethral fistulae were closed.

CONCLUSIONS

Robotic transanal surgery for local excision, transanal total mesorectal excision, and repair of fistulae is feasible, although these new approaches represent a work-in-progress. Improvement in platform design will likely facilitate the ability to perform more complex procedures. Further research with robotic transanal approaches is necessary to determine whether or not this approach can provide patients with significant benefit.

Robotic general surgery: current practice, evidence, and perspective

BACKGROUND

Robotic technology commenced to be adopted for the field of general surgery in the 1990s. Since then, the da Vinci surgical system (Intuitive Surgical Inc, Sunnyvale, CA, USA) has remained by far the most commonly used system in this domain. The da Vinci surgical system is a master-slave machine that offers three-dimensional vision, articulated instruments with seven degrees of freedom, and additional software features such as motion scaling and tremor filtration. The specific design allows hand-eye alignment with intuitive control of the minimally invasive instruments. As such, robotic surgery appears technologically superior when compared with laparoscopy by overcoming some of the technical limitations that are imposed on the surgeon by the conventional approach.

PURPOSE

This article reviews the current literature and the perspective of robotic general surgery.

CONCLUSIONS

While robotics has been applied to a wide range of general surgery procedures, its precise role in this field remains a subject of further research. Until now, only limited clinical evidence that could establish the use of robotics as the gold standard for procedures of general surgery has been created. While surgical robotics is still in its infancy with multiple novel systems currently under development and clinical trials in progress, the opportunities for this technology appear endless, and robotics should have a lasting impact to the field of general surgery.

A Novel Device for Measuring Forces in Endoluminal Procedures

In this paper a simple but effective measuring system for endoluminal procedures is presented. The device allows measuring forces during the endoluminal manipulation of tissues with a standard surgical instrument for laparoscopic procedures. The force measurement is performed by recording both the forces applied directly by the surgeon at the instrument handle and the reaction forces on the access port. The measuring system was used to measure the forces necessary for appropriate surgical manipulation of tissues during transanal endoscopic microsurgery (TEM). Ex-vivo and in-vivo measurements were performed, reported and discussed. The obtained data can be used for developing and appropriately dimensioning novel dedicated instrumentation for TEM procedures.

Transanal total mesorectal excision: a systematic review of the experimental and clinical evidence

Achieving a clear distal or circumferential resection margins with laparoscopic total mesorectal excision (TME) may be laborious, especially in obese males and when operating on advanced distal rectal tumors with a poor response to neoadjuvant treatment. Transanal (TaTME) is a new natural orifice translumenal endoscopic surgery modality in which the rectum is mobilized transanally using endoscopic techniques with or without laparoscopic assistance. We conducted a comprehensive systematic review of publications on this new technique in PubMed and Embase databases from January, 2008, to July, 2014. Experimental and clinical studies written in English were included. Experimental research with TaTME was done on pigs with and without survival models and on human cadavers. In these studies, laparoscopic or transgastric assistance was frequently used resulting in an easier upper rectal dissection and in a longer rectal specimen. To date, 150 patients in 16 clinical studies have undergone TaTME. In all but 15 cases, transabdominal assistance was used. A rigid transanal endoscopic operations/transanal endoscopic microsurgery (TEO/TEM) platform was used in 37 patients. Rectal adenocarcinoma was the indication in all except for nine cases of benign diseases. Operative times ranged from 90 to 460 min. TME quality was deemed intact, satisfactory, or complete. Involvement in circumferential resection margins was detected in 16 (11.8 %) patients. The mean lymph node harvest was equal or greater than 12 in all studies. Regarding morbidity, pneumoretroperitoneum, damage to the urethra, and air embolism were reported intraoperatively. Mean hospital stay varied from 4 to 14 days. Postoperative complications occurred in 34 (22.7 %) patients. TaTME with TEM is feasible in selected cases. Oncologic safety parameters seem to be adequate although the evidence relies on small retrospective series conducted by highly trained surgeons. Further studies are expected.

Robotic transanal total mesorectal excision: a pilot study

BACKGROUND

The introduction of transanal minimally invasive surgery (TAMIS) in 2009 allowed colorectal surgeons to approach transanal access with a different perspective. This has lead to the development of TAMIS for total mesorectal excision (TME). We have previously described robotic transanal TME and here report our initial experience with the first three human cases performed at a single institution.

METHODS

Three patients with distal rectal cancer were selective to undergo robotic transanal TME. All resections were carried out with intent to cure; they were performed by a single attending colorectal surgeon over an 11-month period.

RESULTS

Three patients underwent robotic transanal TME. The average age was 45 years (range 26-59) with mean BMI of 32 kg/m(2) (range 21-38.5). The average tumor size was 2.5 cm. All lesions were located in the distal 5 cm of the rectum. In each case, the distal and circumferential resection margins were free of tumor. The resection quality of the mesorectal envelope was Grade I and Grade II. There was no major morbidity or mortality on short-term follow-up.

CONCLUSIONS

Robotic transanal TME is a new modality for en bloc rectal cancer surgery, and the technique is feasible. Further study is necessary to assess the benefit of this novel approach.

Robotic transanal total mesorectal excision for rectal cancer: experience with a first case

BACKGROUND

A transanal approach for total mesorectal excision (TME) using a single incision port is feasible. The disadvantages are technical difficulties associated with limited manoeuvrability.

METHODS

We present our first experience with robotic-assisted transanal total mesorectal excision. A 48 year-old woman with a tumour 8 cm from the anal verge was successfully operated using a transanal approach. A complete mesorectal excision was performed through a single incision port, using two robot arms.

RESULTS

TME was performed successfully and the patient recovered quickly without any complications. The histological report showed a complete mesorectal excision with free distal and circumferential margins. A sigmoidoscopy showed an intact anastomosis and the patient was planned for reversal of her ileostomy.

CONCLUSIONS

Transanal total mesorectal excision using the robot is feasible. Robotics may help to overcome technical difficulties associated with the single incision port.

A systematic review of transanal minimally invasive surgery (TAMIS) from 2010 to 2013

Transanal minimally invasive surgery (TAMIS) was introduced as an alternative to transanal endoscopic microsurgery in 2010. Over the past 4 years, considerable international experience has been gained with this approach. Most published reports focus on TAMIS for local excision of rectal neoplasia, but there are other important applications such as transanal mesorectal excision for rectal cancer. This comprehensive review details the progress with TAMIS since its inception. Robotic transanal surgery is a natural evolution of TAMIS still in its early infancy, which is also reviewed. A comprehensive search of PubMed, EMBASE, the Cochrane Library, and Web of Knowledge was performed. Since the inception of TAMIS in 2009, 33 retrospective studies and case reports, and 3 abstracts have been published on TAMIS for local excision of rectal neoplasms, which represents a combined n = 390 TAMIS procedures performed worldwide using eight different types of TAMIS platforms. A total of 152 lesions were excised for benign disease including adenomas and high-grade dysplasias (39 %), 209 for malignancy for carcinomas in situ and adenocarcinomas (53.5 %). Twenty-nine (7.5 %) of TAMIS resections were for other pathology, of which the majority (23/29) were neuroendocrine lesions. The remaining resections were for mucocele, gastrointestinal stromal tumor, melanoma, and fibrosis. Robotic-TAMIS has also been reported, however, data are extremely limited as there are only 7 case reports (combined n = 11) in the published literature. Success with Robotic-TAMIS has been demonstrated with various patient positions and by use of a special glove port. Transanal total mesorectal excision using the TAMIS platform has also been demonstrated is several small series, and the feasibility of performing pure transanal total mesorectal excision has also been reported. Combined, n = 78 cases of transanal total mesorectal excision have been performed using TAMIS. The advantages of TAMIS-assisted transanal total mesorectal excision are discussed.

Robotic transanal minimally invasive surgery for local excision of rectal neoplasms

BACKGROUND

Robotic transanal minimally invasive surgery (TAMIS) may be an option for rectum-preserving excision of neoplasms. Recent cadaveric studies showed improved vision, control and manoeuvrability compared with use of laparoscopic instruments. This study reports the clinical application.

METHODS

Consecutive patients eligible for transanal endoscopic microsurgery (TEM) or TAMIS in three participating centres were operated on using a robotic platform and transanal glove port. Patient demographics, lesion characteristics, perioperative data, complications and follow-up of all patients were recorded prospectively.

RESULTS

Sixteen patients underwent robotic TAMIS for rectal lesions with a median (range) distance from the anal verge of 8 (range 3-10) cm. The median size of the resected specimen was 5·3 (0·5-21) cm(2) . The median docking time and duration of operation were 36 (18-75) and 108 (40-180) min respectively. One conversion to regular (non-robotic) TAMIS was needed owing to difficulties accessing the rectum. Glove puncture necessitated replacement in four procedures, an unstable pneumorectum arose during one operation and one patient developed a pneumoperitoneum. One patient required catheterization for urinary retention. The median hospital stay was 1·3 (0-4) days. The additional cost of the robotic approach was approximately €1000 per procedure (excluding the capital expenditure on the robotic system and its maintenance).

CONCLUSION

Robotic TAMIS is feasible in patients with rectal lesions. Potential advantages over TEM and non-robotic TAMIS will need to be balanced against the cost of the robotic system.

A systematic review of transanal minimally invasive surgery (TAMIS) from 2010 to 2013

Transanal minimally invasive surgery (TAMIS) was introduced as an alternative to transanal endoscopic microsurgery in 2010. Over the past 4 years, considerable international experience has been gained with this approach. Most published reports focus on TAMIS for local excision of rectal neoplasia, but there are other important applications such as transanal mesorectal excision for rectal cancer. This comprehensive review details the progress with TAMIS since its inception. Robotic transanal surgery is a natural evolution of TAMIS still in its early infancy, which is also reviewed. A comprehensive search of PubMed, EMBASE, the Cochrane Library, and Web of Knowledge was performed. Since the inception of TAMIS in 2009, 33 retrospective studies and case reports, and 3 abstracts have been published on TAMIS for local excision of rectal neoplasms, which represents a combined n = 390 TAMIS procedures performed worldwide using eight different types of TAMIS platforms. A total of 152 lesions were excised for benign disease including adenomas and high-grade dysplasias (39 %), 209 for malignancy for carcinomas in situ and adenocarcinomas (53.5 %). Twenty-nine (7.5 %) of TAMIS resections were for other pathology, of which the majority (23/29) were neuroendocrine lesions. The remaining resections were for mucocele, gastrointestinal stromal tumor, melanoma, and fibrosis. Robotic-TAMIS has also been reported, however, data are extremely limited as there are only 7 case reports (combined n = 11) in the published literature. Success with Robotic-TAMIS has been demonstrated with various patient positions and by use of a special glove port. Transanal total mesorectal excision using the TAMIS platform has also been demonstrated is several small series, and the feasibility of performing pure transanal total mesorectal excision has also been reported. Combined, n = 78 cases of transanal total mesorectal excision have been performed using TAMIS. The advantages of TAMIS-assisted transanal total mesorectal excision are discussed.

Robotic transanal surgery for local excision of rectal neoplasms

Robotic transanal surgery (RTS) has been a natural evolution of transanal minimally invasive surgery. This video demonstrates how RTS is performed for the full-thickness excision of a malignant rectal polyp, with endoluminal robotic suturing of the rectal wall defect. The general approach to RTS, including the approach to docking of the robotic cart, are also illustrated in video format.

Robotic colorectal surgery: summary of the current evidence

BACKGROUND

Several studies have confirmed that laparoscopic colorectal surgery results in improved early post-operative outcomes. Nevertheless, conventional laparoscopic approach and instruments have several limitations. Robotic approach could potentially address of many of these limitations.

OBJECTIVES

This review aims to present a summary of the current evidence on the role of robotic colorectal surgery.

METHODS

A comprehensive search of electronic databases (Pubmed, Science Direct and Google scholar) using the key words "rectal surgery", "laparoscopic", "colonic" and "robotic." Evidence from these data was critically analysed and summarised to produce this article.

RESULTS

Robotic colorectal surgery is both safe and feasible. However, it has no clear advantages over standard laparoscopic colorectal surgery in terms of early postoperative outcomes or complications profile. It has shorter learning curve but increased operative time and cost. It could offer potential advantage in resection of rectal cancer as it has a lower conversion rates even in obese individuals, distal rectal tumours and patients who had preoperative chemoradiotherpy. There is also a trend towards better outcome in anastomotic leak rates, circumferential margin positivity and perseveration of autonomic function, but there was no clear statistical significance to support this from the currently available data.

CONCLUSION

The use of robotic approach seems to be capable of addressing most of the shortcomings of the standard laparoscopic surgery. The technique has proved its safety profile in both colonic and rectal surgery. However, the cost involved may restrict its use to patients with challenging rectal cancer and in specialist centres.

Transanal minimally invasive surgery for total mesorectal excision (TAMIS-TME): results and experience with the first 20 patients undergoing curative-intent rectal cancer surgery at a single institution

BACKGROUND

Transanal TME is a new approach to performing minimally invasive rectal resection. It is particularly well suited for patients with locally advanced distal rectal cancer and obesity, where the abdominal approach is challenging. Transanal TME can be performed with either TAMIS or TEM. Here, we report our initial experience with transanal TME using TAMIS (TAMIS-TME).

METHODS

Patients were selected to undergo transanal TME using the TAMIS platform (TAMIS-TME) primarily for malignant disease, but also for select cases of benign disease. Transanal TME defines a "bottom-up" approach to en bloc rectal cancer resection. Transanal TME requires abdominal access for proximal colonic mobilization and is often done in conjunction with a laparoscopic approach.

RESULTS

During a 32-month period, 20 patients underwent TAMIS-TME with curative intent. The primary indication for transanal TME was distal, locally advanced rectal cancer. The median age of rectal cancer patients at the time of surgery was 57 years (range 36-73 years) with 30% (6) female and 70% (14) male. The median body mass index (BMI) measured was 24 kg/m(2) (range 18-41 kg/m(2)); this included six patients (30%) with obesity (BMI ≥ 30 kg/m(2)). Mean operating time was 243 min (range 140-495 min) with blood loss averaging 153 ml. Postoperative length of stay averaged 4.5 days (range 3-24 days). There was no 30-day postoperative mortality. Surgical complications included wound infection (n = 2), pelvic abscess (n = 4), and prolonged ileus (n = 4). The anastomotic leak rate was 6.7% (1/15). Of the 20 patients who underwent resection, 90% (18/20) had negative margins. Pathologic grading of the TME specimen revealed that 85% (17/20) of transanal TME specimens were found to have "completely" or "near-completely" intact mesorectal envelopes. Data collected during the 6-month median follow-up period revealed that only one patient had developed distant metastasis. There was no locoregional recurrence in any of the patients.

CONCLUSIONS

Transanal TME is a feasible method for oncologic resection of locally advanced mid- and distal-rectal cancer with curative intent. It has special application for patients with obesity and anatomic constraints such as a narrow male pelvis.

Robotic transanal endoscopic microsurgery: technical details for the lateral approach

BACKGROUND

Transanal endoscopic microsurgery is a minimally invasive approach reserved for the resection of selected rectal tumors. However, this approach is technically demanding. Although robotic technology may overcome the limitations of this approach, the system can be difficult to dock, especially in the lithotomy position.

OBJECTIVE

The study aim is thus to report the technical details of robotic transanal endoscopic microsurgery with the use of a lateral approach.

DESIGN AND SETTINGS

This study is a prospective evaluation of robotic transanal endoscopic microsurgery in a single tertiary institution, under a protocol approved by our local ethics committee.

INTERVENTION

Patients underwent a routine mechanical bowel preparation and were placed in the left or right lateral position according to the tumor location. A circular anal dilatator was used together with the glove port technique. The robotic system was then docked over the hip. A 30° optic and 2 articulated instruments were used with an additional assistant trocar. The tumor excision was realized with an atraumatic grasper and an articulated cautery hook, and the defect was closed with barbed continuous stiches in each case.

MAIN OUTCOME MEASURE

The primary outcome was the safety and feasibility of the procedure.

RESULTS

Three patients underwent a robotic transanal endoscopic microsurgery with the use of the lateral approach. Mean operative time was 110 minutes, including 20 minutes for the docking of the robot. There was 1 intraoperative complication (a pneumoperitoneum without intraabdominal lesion) and no postoperative complications. Mean hospital stay was 3 days. Margins were negative in all the cases.

LIMITATIONS

The study was limited by the small number of patients.

CONCLUSION

Robotic transanal endoscopic microsurgery with use of the lateral approach is feasible and may facilitate the local resection of small lesions of the mid and lower rectum. It might assume an important place in sphincter-preserving surgery, especially for selected and early rectal cancer (see Video, Supplemental Digital Content 1, http://links.lww.com/DCR/A114).

Robotic transanal endoscopic microsurgery in benign rectal tumour

AIM

To present a case of resection of a rectal tumour by a transanal robotic approach.

PATIENT

A 58-year-old woman with a 3-cm tumour located 6 cm proximal to anal verge (uT1N0).

RESULTS

We describe the details of the surgical technique. A complete resection with adequate margins was accomplished. The defect was closed with a running suture. Operation time was 180 min. There were no complications and the patient was discharged 24 h after surgery.

CONCLUSION

A complete resection of a rectal tumour by a robotic approach is feasible and safe. More studies are needed to clearly define the indications where this new approach can show clear advantages over other transanal resection approaches.

Robotic-assisted transanal surgery for total mesorectal excision (RATS-TME): a description of a novel surgical approach with video demonstration

A new era has emerged in rectal cancer surgery--transanal total mesorectal excision (TME). Various platforms have been used to facilitate this novel approach, including transanal minimally invasive surgery (TAMIS) and transanal endoscopic microsurgery. We have previously reported the use of TAMIS-TME. This is a report of the first human case of robotic-assisted transanal surgery for TME.

Transanal minimally invasive surgery (TAMIS): applications beyond local excision

Transanal minimally invasive surgery (TAMIS) is a new technique for the local excision of rectal neoplasia. This platform employs ordinary laparoscopic instruments to achieve high-quality local excision. The TAMIS platform, however, is quite versatile. Described here are applications of TAMIS beyond local excision, ranging from repair of a rectourethral fistula to reverse proctectomy.

Current status of robotic rectal cancer surgery

SUMMARY After the introduction of robotic surgery for rectal cancer, the safety and feasibility of robotic rectal cancer surgery was demonstrated. However, early comparative studies between laparoscopic and robotic surgery did not show a significant postoperative benefit. Recently, it was reported that robotic rectal surgery showed better postoperative outcomes than laparoscopic surgery with regard to postoperative recovery, pain and function preservation. In addition, robotic transanal specimen extraction was safely performed while maintaining a lower level of postoperative pain and recovery time. All of these findings should be validated with well-designed comparative studies. As robotic technology advances and continues to be studied, the use of robotic surgical systems will become more common among colorectal surgeons.