Robotic-assisted transanal total mesorectal excision for rectal cancer: technique and results from a single institution. Tech Coloproctol. 2021;25:693-700. [PMID: 32955640 DOI: 10.1007/s10151-020-02337-z]

Current status of transanal total mesorectal excision for rectal cancer and the expanding indications of the transanal approach for extended pelvic surgeries

Transanal total mesorectal excision (taTME) has been rapidly accepted as a promising surgical approach to the distal rectum. The benefits include ease of access to the bottom of the deep pelvis linearly over a short distance in order to easily visualize the important anatomy. Furthermore, the distal resection margins can be secured under direct vision. Additionally, a two-team approach combining taTME with a transabdominal approach could decrease the operative time and conversion rate. Although taTME was expected to become more rapidly popularized worldwide, enthusiasm for it has stalled due to unfamiliar intraoperative complications, a lack of oncologic evidence from randomized trials, and the widespread use of robotic surgery. While international registries have reported favorable short- and medium-term outcomes from taTME, a Norwegian national study reported a high local recurrence rate of 9.5%. The characteristics of the recurrences included rapid, multifocal growth in the pelvis, which was quite different from recurrences following traditional transabdominal TME; thus, the Norwegian Colorectal Cancer Group reached a consensus for a temporary moratorium on the performance of taTME. To ensure acceptable baseline quality and patient safety, taTME should be performed by well-trained colorectal surgeons. Although the appropriate indications for taTME remain controversial, the transanal approach is extremely important as a means of goal setting in difficult TME cases and as an aid to the transabdominal approach in various types of extended pelvic surgeries. The benefits in transanal lateral lymph node dissection and pelvic exenteration are presented herein.

Robotic Transanal Total Mesorectal Excision Compared to Laparoscopic Transanal Total Mesorectal Excision: Oncologic Results of the Past 5 Years

Colorectal cancer is one of the deadliest diseases on the planet. Rectal cancer (RC) is the 8 th most common type of cancer disease worldwide, accounting for over 300,000 fatalities in 2018. Total mesorectal excision (TME) is considered as the gold standard approach for surgical RC management. To alleviate technical problems associated with dissection of distal rectal, transanal procedure to mesorectum was developed. The robotic operating platforms’ development has brought about the most significant change. The robotic method, which was described first in the year 2001, is gaining popularity in colorectal surgery. A stable camera platform with three-dimensional imaging and tremor filtering, motion scaling, instruments with numerous degrees of freedom, 3 rd arm for fixed retraction, ambidextrous capability, superior ergonomics, and less fatigue, all these advantages have all influenced robotics implementation. However, there are certain disadvantages to robotic surgery, such as high expenses, lengthy time of operation, a bulky cart, and absence of haptic sense. Robotic transanal TME (R-TA TME) is unique method that integrates potential advantages of perineal dissection with precise control of distal margins, along with all robotic technology advantages with respect to dexterity and greater precision. This review goal is to evaluate the available literature critically regarding R-TA TME in comparison to laparoscopic TA TME (L-TA TME) using the most prevalent histopathological metrics, which are the circumferential resection margin, the distal rectal margin, recurrence rate, specimen quality, advantages, and disadvantages. Oncological results for the past 5 years were used. The resources were obtained from electronic sources such as Google Scholar and PubMed. The conclusion of this review revealed that R-TA TME is as safe as well as feasible as L-TA TME, is technically possible, and has comparable oncological results and short-term post-operative outcomes. However, further investigation is required to evaluate long-term oncological or functional results.

Robotic Surgery in Rectal Cancer: Potential, Challenges, and Opportunities

The current standard treatment for locally advanced rectal cancer is based on a multimodal comprehensive treatment combined with preoperative neoadjuvant chemoradiation and complete surgical resection of the entire mesorectal cancer. For ultra-low cases and cases with lateral lymph node metastasis, due to limitations in laparoscopic technology, the difficulties of operation and incidence of intraoperative complications are always difficult to overcome. Robotic surgery for the treatment of rectal cancer is an emerging technique that can overcome some of the technical drawbacks posed by conventional laparoscopic approaches, improving the scope and effect of radical operations. However, evidence from the literature regarding its oncological safety and clinical outcomes is still lacking. This brief review summarized the current status of robotic technology in rectal cancer therapy from the perspective of several mainstream surgical methods, including robotic total mesorectal excision (TME), robotic transanal TME, robotic lateral lymph node dissection, and artificial intelligence, focusing on the developmental direction of robotic approach in the field of minimally invasive surgery for rectal cancer in the future.

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.

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.

Age and comorbidities do not affect short-term outcomes after laparoscopic rectal cancer resection in elderly patients. A multi-institutional cohort study in 287 patients

Postoperative complications and mortality rates after rectal cancer surgery are higher in elderly than in non-elderly patients. The aim of this study is to evaluate whether, like in open surgery, age and comorbidities affect postoperative outcomes limiting the benefits of a laparoscopic approach. Between April 2011 and July 2020, data of 287 patients with rectal cancer submitted to laparoscopic rectal resection from different institutions were collected in an electronic database and were categorized into two groups: < 75 years and ≥ 75 years of age. Perioperative data and short-term outcomes were compared between these groups. Risk factors for postoperative complications were determined on multivariate analysis, including age groups and previous comorbidities as variables. Seventy-seven elderly patients had both higher ASA scores (p < 0.001) and cardiovascular disease rates (p = 0.02) compared with 210 non-elderly patients. There were no significative differences between groups in terms of overall postoperative complications (p = 0.3), number of patients with complications (p = 0.2), length of stay (p = 0.2) and death during hospitalization (p = 0.9). The only independent variables correlated with postoperative morbidity were male gender (OR 2.56; 95% CI 1.53-3.68, p < 0.01) and low-medium localization of the tumor (OR 2.12; 75% CI 1.43-4.21, p < 0.01). Although older people are more frail patients, short-term postoperative outcomes in patients ≥ 75 years of age were similar to those of younger patients after laparoscopic surgery for rectal cancer. Elderly patients benefit from laparoscopic rectal resection as well as non-elderly patient, despite advanced age and comorbidities.