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

Single-port robotic transanal minimally invasive surgery (SPR-TAMIS): another giant leap forward?

AIM

Minimally invasive transanal platforms are now the standard of care for select low-risk rectal tumours. However, existing platforms come with persistent technical challenges. The da Vinci SP Surgical System™ offers a new alternative designed to work effectively in narrow spaces. This technology has the potential to enhance the feasibility and proximal extent of complex transanal resections. This study aimed to describe the morbidity and technical success in patients undergoing single-port robotic transanal minimally invasive surgery (SPR-TAMIS). Secondary outcomes include rates of local recurrence.

METHODS

A retrospective analysis was conducted on all patients who underwent SPR-TAMIS at our institution between February 2019 and December 2023.

RESULTS

The study included 31 patients (19 men, 12 women) with a mean age of 61 ± 13.3 years. The average tumour distance from the anal verge was 10 cm. Thirty patients completed SPR-TAMIS, with one patient requiring conversion to robotic sigmoidectomy due to location in the mid-sigmoid colon. The mean operating time was 106 ± 42 min. Twenty-eight out of 30 patients underwent full-thickness excision and all but two were successfully closed. All specimens were resected intact, and margins were negative in 93.5% of cases. The average tumour size was 13 ± 34 cm2, with 13 lesions classified as adenomas and 16 as adenocarcinomas. All patients who did not undergo associated procedures were discharged on the day of surgery. Two patients experienced 30-day morbidity. At a mean follow-up of 18 months (± 13), no local or systemic recurrences were identified.

CONCLUSION

SPR-TAMIS for excision of low-risk rectal tumours is associated with high rates of technical success and low 30-day morbidity. Further research is needed to compare SPR-TAMIS with other techniques to determine potential advantages over current transanal platforms.

Robotic transanal minimally invasive surgery (R-TAMIS): current evidence in the treatment of early rectal neoplasia

INTRODUCTION

Robotic transanal minimally invasive surgery (R-TAMIS) was introduced in 2012 for the excision of benign rectal polyps and low grade rectal cancer. Ergonomic improvements over traditional laparoscopic TAMIS (L-TAMIS) include increased dexterity within a small operative field, with possibility of better surgical precision. We aim to collate the existing data surrounding the use of R-TAMIS to treat rectal neoplasms from cohort studies and larger case series, providing a foundation for future, large-scale, comparative studies.

METHODS

Medline, EMBASE and Web of Science were searched as part of our review. Randomised controlled trials (RCTs), cohort studies or large case series (≥ 5 patients) investigating the use of R-TAMIS to resect rectal neoplasia (benign or malignant) were eligible for inclusion in our analysis. Quality assessment of included studies was performed via the Newcastle Ottawa Scale (NOS) risk of bias tool. Outcomes extracted included basic participant characteristics, operative details and histopathological/oncological outcomes.

RESULTS

Eighteen studies on 317 participants were included in our analysis. The quality of studies was generally satisfactory. Overall complication rate from R-TAMIS was 9.7%. Clear margins (R0) were reported in 96.2% of patients. Local recurrence (benign or malignant) occurred in 2.2% of patients during the specified follow-up periods.

CONCLUSION

Our review highlights the current evidence for R-TAMIS in the local excision of rectal lesions. While R-TAMIS appears to have complication, margin negativity and recurrence rates superior to those of published L-TAMIS series, comparative studies are needed.

pT1 colorectal cancer: A treatment dilemma

The implementation of population screening programs for colorectal cancer (CRC) has led to a considerable increase in the prevalence pT1-CRC originating on polyps amenable by local treatments. However, a high proportion of patients are referred for unnecessary oncological surgeries without a clear benefit in terms of survival. Selecting the appropriate endoscopic resection technique in the moment of diagnosis becomes crucial to provide the best treatment alternative to each individual polyp and patient. For this, it is imperative to increase the optical diagnostic skill for differentiating pT1-CRCs and decide the appropriate initial therapy. En bloc resection is crucial to obtain an adequate histological specimen that might allow organ preserving therapeutic management. In this review, we address key challenges in T1 CRC management, explore the efficacy and safety of the available diagnostic and therapeutic approaches, and shed light on upcoming advances in the field.

Robot-assisted TAMIS: a systematic review of feasibility and outcomes

BACKGROUND

In the advancement of transanal local excision, robot-assisted transanal minimal invasive surgery is the newest development. In the confined area of the rectum, robot-assisted surgery should, theoretically, be superior due to articulated utensils, video enhancement, and tremor reduction, however, this has not yet been investigated. The aim of this study was to review the evidence reported to-date on experience of using robot-assisted transanal minimal invasive surgery for treatment of rectal neoplasms.

METHODS

A comprehensive literature search of Embase and PubMed from May to August 2021were performed. Studies including patients diagnosed with rectal neoplasia or benign polyps who underwent robot-assisted transanal minimal invasive surgery were included. All studies were assessed for risk of bias through assessment tools. Main outcome measures were feasibility, excision quality, and complications.

RESULTS

Twenty-five studies with a total of 322 local excisions were included. The studies included were all retrospective, primarily case-reports, -series, and cohort studies. The median distance from the anal verge ranged from 3.5 to 10 cm and the median size was between 2.5 and 5.3 cm. Overall, 4.6% of the resections had a positive resection margin. The overall complication rate was at 9.5% with severe complications (Clavien-Dindo score III) at 0.9%.

CONCLUSION

Based on limited, retrospective data, with a high risk of bias, robot-assisted transanal minimal invasive surgery seems feasible and safe for local excisions in the rectum.

Transanal full-thickness excision for rectal neoplasm: is it advisable to leave the defect open?

PURPOSE

After a full-thickness total wall excision of a rectal tumor, suturing the defect is generally recommended. Recently, due to various contradictory studies, there is a trend to leave the defects open. Therefore, this study aimed to determine whether leaving the defect open is an adequate management strategy compared with suturing it closed based on postoperative outcomes and recurrences.

METHODS

A retrospective review of our prospectively maintained database was conducted. Adult patients who underwent transanal surgery for rectal neoplasm in our institution from 1997 to 2019 were analyzed. Patients were divided into two groups: sutured (group A) or unsutured (group B) rectal defect. The primary outcomes were morbidity (early and late) and recurrence.

RESULTS

In total, 404 (239 men) patients were analyzed, 143 (35.4%) from group A and 261 (64.6%) from group B. No differences were observed in tumor size, distance from the anal verge or operation time. The overall incidence of complications was significantly higher in patients from group B, which nearly double the rate of group A. With a mean follow-up of 58 (range, 12-96) months, seven patients presented with a rectal stricture, all of them from group B.

CONCLUSIONS

We acknowledge the occasional impossibility of closing the defect in patients who undergo local excision; however, when it is possible, the present data suggest that there may be advantages to suturing the defect closed.

Local full-thickness excision for sessile adenoma and cT1-2 rectal cancer: long-term oncological outcome

PURPOSE

We analyzed all patients who underwent local transanal surgery at our institution to determine oncological outcomes and perioperative risk.

METHODS

In 1997, we developed a prospective protocol for rectal tumors: transanal local full-thickness excision was considered curative in patients with benign adenoma and early cancers. In this analysis, 404 patients were included. To analyze survival, only those patients exposed to the risk of dying for at least 5 years were considered for the study.

RESULTS

The final pathological analysis revealed that 262 (64.8%) patients had benign lesions, whereas 142 had malignant lesions. Postoperative complications were recorded in 12.6%. At the median time of 21 months, 14% of the adenomas and 12% of cancers had recurred, half of which were surgically resected. The overall 5-year survival rate was 94%.

CONCLUSION

With similar outcomes and significantly lower morbidity, we found local surgery to be an adequate alternative to radical surgery in selected cases of early rectal cancer.

Comparison of advanced techniques for local excision of rectal lesions: a case series

Background

Robotic transanal minimally invasive surgery (R-TAMIS) is an appealing alternative to transanal minimally invasive surgery (TAMIS) and transanal endoscopic microsurgery (TEM) for benign and early malignant rectal lesions that are not amenable to traditional open transanal excision. However, no studies to our knowledge have directly compared the three techniques. This study sought to compare peri-operative and pathologic outcomes of the three approaches.

Methods

The records of 29 consecutive patients who underwent TEM, TAMIS, or R-TAMIS at a single academic center between 2016 and 2020 were reviewed. Intra-operative details, pathological diagnosis and margins, and post-operative outcomes were recorded. The three groups were compared using chi-square and Kruskal–Wallis tests.

Results

Overall, 16/29 patients were women and the median age was 57 (interquartile range (IQR): 28–81). Thirteen patients underwent TEM, six had TAMIS, and 10 had R-TAMIS. BMI was lower in the R-TAMIS patients (24.7; IQR 23.8–28.7), than in TEM (29.3; IQR 19.9–30.2), and TAMIS (30.4; IQR 26.6–32.9) patients. High grade dysplasia and/or invasive cancer was more common in TAMIS (80%) and R-TAMIS (66.7%) patients than in TEM patients (41.7%). The three groups did not differ significantly in tumor type or distance from the anal verge. No R-TAMIS patients had a positive surgical margin compared to 23.1% in the TEM group and 16.7% in the TAMIS group. Length of stay (median 1 day for TEM and R-TAMIS patients, 0 days for TAMIS patients) and 30-day readmission rates (7.7% of TEM, 0% of TAMIS, 10% of R-TAMIS patients) also did not differ among the groups. Median operative time was 110 min for TEM, 105 min for TAMIS, and 76 min for R-TAMIS patients.

Conclusions

R-TAMIS may have several advantages over other advanced techniques for transanal excisions. R-TAMIS tended to be faster and to more often result in negative surgical margins compared to the two other techniques.

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.