Surgical outcomes of robotic transanal minimally invasive surgery for selected rectal neoplasms: A single-hospital experience

Robotic transanal minimally invasive surgery (r-TAMIS): perioperative and short-term outcomes for local excision of rectal cancers

BACKGROUND

Transanal minimally invasive surgery (TAMIS) is an advanced technique for excision of early rectal cancers. Robotic TAMIS (r-TAMIS) has been introduced as technical improvement and potential alternative to total mesorectal excision (TME) in early rectal cancers and in frail patients. This study reports the perioperative and short-term oncological outcomes of r-TAMIS for local excision of early-stage rectal cancers.

METHODS

Retrospective analysis of a prospectively collected r-TAMIS database (July 2021-July 2023). Demographics, clinicopathological features, short-term outcomes, recurrences, and survival were investigated.

RESULTS

Twenty patients were included. Median age and body mass index were 69.5 (62.0-77.7) years and 31.0 (21.0-36.5) kg/m2. Male sex was prevalent (n = 12, 60.0%). ASA III accounted for 66.7%. Median distance from anal verge was 7.5 (5.0-11.7) cm. Median operation time was 90.0 (60.0-112.5) minutes. Blood loss was minimal. There were no conversions. Median postoperative stay was 2.0 (1.0-3.0) days. Minor and major complication rates were 25.0% and 0%, respectively. Seventeen (85.0%) patients had an adenocarcinoma whilst three patients had an adenoma. R0 rate was 90.0%. Most tumours were pT1 (55.0%), followed by pT2 (25.0%). One patient (5.0%) had a pT3 tumour. Specimen and tumour maximal median diameter were 51.0 (41.0-62.0) mm and 21.5 (17.2-42.0) mm, respectively. Median specimen area was 193.1 (134.3-323.3) cm2. Median follow-up was 15.5 (10.0-24.0) months. One patient developed local recurrence (5.0%).

CONCLUSIONS

r-TAMIS, with strict postoperative surveillance, is a safe and feasible approach for local excision of early rectal cancer and may have a role in surgically unfit and elderly patients who refuse or cannot undergo TME surgery. Future prospective multicentre large-scale studies are needed to report the long-term oncological outcomes.

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.

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.

Imaging-Navigated Surgery

It is vitally important to guide or navigate therapeutic proceedings with a direct and visual approach in order to carefully undertake precision medical manipulations and efficiently evaluate the treatments. Imaging-navigated surgery is one of the common and prevailing technologies to realize this target, and more importantly it merges visualized medicine into next-generation theranostic paradigms in modern medicine. Endoscopes, surgical robots, and nanorobots are three major domains in terms of imaging-navigated surgery. The history of endoscopy has seen upgraded developments since the early 1800s. In contrast, surgical robots have been widely used and investigated in recent years, and they came into clinical uses only in the past decades. Nanorobots which closely depend on innovated and multifunctional biomaterials are still in their infancy. All these imaging-navigated technologies show similar and apparent advantages such as minimal invasiveness, minimized pain, positive prognosis, and relatively expected recovery, which have greatly improved surgery efficiency and patients' life quality. Therefore, the imaging-navigated surgery will be discussed in this chapter, and advanced clinical and preclinical medical applications will also be demonstrated for a diverse readers and comprehensive understanding.

Risk of recurrence after local resection of T1 rectal cancer: a meta-analysis with meta-regression

BACKGROUND

T1 rectal cancer (RC) patients are increasingly being treated by local resection alone but uniform surveillance strategies thereafter are lacking. To determine whether different local resection techniques influence the risk of recurrence and cancer-related mortality, a meta-analysis was performed.

METHODS

A systematic search was conducted for T1RC patients treated with local surgical resection. The primary outcome was the risk of RC recurrence and RC-related mortality. Pooled estimates were calculated using mixed-effect logistic regression. We also systematically searched and evaluated endoscopically treated T1RC patients in a similar manner.

RESULTS

In 2585 unique T1RC patients (86 studies) undergoing local surgical resection, the overall pooled cumulative incidence of recurrence was 9.1% (302 events, 95% CI 7.3-11.4%; I2 = 68.3%). In meta-regression, the recurrence risk was associated with histological risk status (p < 0.005; low-risk 6.6%, 95% CI 4.4-9.7% vs. high-risk 28.2%, 95% CI 19-39.7%) and local surgical resection technique (p < 0.005; TEM/TAMIS 7.7%, 95% CI 5.3-11.0% vs. other local surgical excisions 10.8%, 95% CI 6.7-16.8%). In 641 unique T1RC patients treated with flexible endoscopic excision (16 studies), the risk of recurrence (7.7%, 95% CI 5.2-11.2%), cancer-related mortality (2.3%, 95% CI 1.1-4.9), and cancer-related mortality among patients with recurrence (30.0%, 95% CI 14.7-49.4%) were comparable to outcomes after TEM/TAMIS (risk of recurrence 7.7%, 95% CI 5.3-11.0%, cancer-related mortality 2.8%, 95% CI 1.2-6.2% and among patients with recurrence 35.6%, 95% CI 21.9-51.2%).

CONCLUSIONS

Patients with T1 rectal cancer may have a significantly lower recurrence risk after TEM/TAMIS compared to other local surgical resection techniques. After TEM/TAMIS and endoscopic resection the recurrence risk, cancer-related mortality and cancer-related mortality among patients with recurrence were comparable. Recurrence was mainly dependent on histological risk status.

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.

Management of Early-Stage Rectal Cancer

A 59-year-old man underwent screening colonoscopy that identified a 2-cm rectal polyp in the posterior midline, 7 cm from the anal verge. Biopsy revealed a tubular adenoma with high-grade dysplasia. The patient underwent a robotic-assisted transanal minimally invasive surgery with full-thickness excision (Fig. 1). Final pathology confirmed a well-differentiated adenocarcinoma extending into the submucosa (sm2). There was no lymphovascular or perineural invasion, and the radial margin was 5 mm.

Robotic transanal minimally invasive surgery: a case series

INTRODUCTION

This study describes the experience with robot-assisted transanal minimally invasive surgery (rTAMIS) at a single institution. TAMIS has become a popular minimally invasive technique for local excision of well-selected rectal lesions. rTAMIS has been proposed as another option as it improves the ergonomics of conventional laparoscopic techniques.

METHODS

Retrospective case series of patients with rectal lesions who underwent rTAMIS. Patient demographics, final pathology, surgical and admission details, and clinical outcomes were recorded. Successful procedures were defined as having negative margins on final pathology.

RESULTS

A total of 16 patients underwent rTAMIS by a single surgeon between April 2018 and December 2019. Mean age of patients was 63 years. Final pathologies were negative for tumor (n = 4), tubulovillous adenoma (n = 4), tubulovillous adenoma with high-grade dysplasia (n = 4), and invasive rectal adenocarcinoma (n = 4). 43% were located in the middle rectum and 56% were located in the distal rectum. Mean maximum diameter was 4.1 cm (IQR 2-3.1 cm). Negative margins were seen in 100% of the excision cases, and 100% were intact. Mean operative time was 87 min (IQR 54.8-97.3 min), and median length of stay was 0 days (IQR 0-1 days). Postoperative complications included incontinence (n = 1) and abscess formation (n = 2). rTAMIS provided curative treatment for 12/16 patients, and the remaining 4 patients received the appropriate standard of care for their respective pathologies.

CONCLUSIONS

Robot-assisted TAMIS is a safe alternative to laparoscopic TAMIS for resection of appropriate rectal polyps and early rectal cancers. rTAMIS may provide a modality for resecting larger or more proximal rectal lesions due to the wristed instruments and superior visualization with the robotic camera. Future studies should focus on comparing outcomes between robotic and laparoscopic TAMIS, and whether rTAMIS allows for the removal of larger, more complex lesions, which may save patients from a more morbid radical proctectomy.