Comparison of laparoscopic versus robot-assisted versus transanal total mesorectal excision surgery for rectal cancer: a retrospective propensity score-matched cohort study of short-term outcomes

Multi-Modal Machine Learning for Evaluating the Predictive Value of Pelvimetric Measurements (Pelvimetry) for Anastomotic Leakage After Restorative Low Anterior Resection

Background/Objectives: Anastomotic leakage (AL) remains a major complication after restorative rectal cancer surgery, with accurate preoperative risk stratification posing a significant challenge. Pelvic measurements derived from magnetic resonance imaging (MRI) have been proposed as potential predictors of AL, but their clinical utility remains uncertain. Methods: This retrospective, multicenter cohort study analyzed rectal cancer patients undergoing restorative surgery between 2013 and 2021. Pelvic dimensions were assessed using MRI-based pelvimetry. Univariate and multivariate regression analyses identified independent risk factors for AL. Subsequently, machine Learning (ML) models-logistic regression, random forest classifier, and XGBoost-were developed to predict AL using preoperative clinical data alone and in combination with pelvimetry. Model performance was evaluated using F1 scores, with the area under the receiver operating characteristic (ROC-AUC) and precision-recall curves (AUC-PR) as primary metrics. Results: Among 487 patients, the overall AL rate was 14%. Multivariate regression analysis identified distance to the anorectal junction, pelvic inlet width, and interspinous distance as independent risk factors for AL (p < 0.05). The logistic regression model incorporating pelvimetry achieved the highest predictive performance, with a mean ROC-AUC of 0.70 ± 0.09 and AUC-PR of 0.32 ± 0.10. Although predictive models that included pelvic measurements demonstrated higher ROC-AUCs compared to those without pelvimetry, the improvement was not statistically significant. Conclusions: Pelvic dimensions, specifically pelvic inlet and interspinous distance, were independently associated with an increased risk of AL. While ML models incorporating pelvimetry showed only moderate predictive performance, these measurements should be considered in developing clinical prediction tools for AL to enhance preoperative risk stratification.

Oncologic safety and technical feasibility of completion transanal total mesorectal excision after local excision; a cohort study from the International TaTME Registry

BACKGROUND

As part of an organ sparing strategy, a surgical local excision may be performed in patients with early-stage rectal cancer or following neoadjuvant (chemo)radiotherapy. In selected cases, a completion total mesorectal excision may be recommended which can be more complex because of the preceding local excision. A transanal approach to perform completion total mesorectal excision may offer an advantage through the better visualization of the surgical field in the distal rectum and less forceful retraction for exposure. However, the oncologic safety and technical feasibility of this approach have yet to be demonstrated in these patients. Therefore, the aim of this study was to evaluate the oncological and technical safety of completion transanal total mesorectal excision following a local excision in patients with rectal cancer.

METHODS

Patients from the prospective International Transanal Total Mesorectal Excision Registry who underwent a surgical local excision prior to completion transanal total mesorectal excision were retrospectively analyzed.

RESULTS

In total, 189 patients were included of which 22% received neoadjuvant radiotherapy. In 94% of the patients, a low anterior resection was performed. A primary anastomosis was constructed in 91% (n = 171/189) of the patients, with the majority also receiving a defunctioning stoma (84%, n = 144/171), of which 69% (n = 100/144) were reversed. Within 30 days, 7% developed an anastomotic leakage. The two-year local recurrence rate was 5% (n = 5/104) with an estimated rate of 3% (95% CI 0-7%). Two-year disease-free survival was 85% (n = 88/104) and overall survival was 95% (n = 99/104).

CONCLUSIONS

Transanal completion total mesorectal excision following local excision for rectal cancer is oncologically safe, with low complication rates and high restorative rates.

Functional outcomes and quality of life following open versus laparoscopic versus robot-assisted versus transanal total mesorectal excision in rectal cancer patients: a systematic review and meta-analysis

BACKGROUND

The standard surgical treatment for rectal cancer is total mesorectal excision (TME), which may negatively affect patients' functional outcomes and quality of life (QoL). However, it is unclear how different TME techniques may impact patients' functional outcomes and QoL. This systematic review and meta-analysis evaluated functional outcomes of urinary, sexual, and fecal functioning as well as QoL after open, laparoscopic (L-TME), robot-assisted (R-TME), and transanal total mesorectal excision (TaTME).

METHODS

A systematic review and meta-analysis, based on the preferred reporting items for systematic reviews and meta-analysis statement, were conducted (PROSPERO: CRD42021240851). A literature review was performed (sources: PubMed, Medline, Embase, Scopus, Web of Science, and Cochrane Library databases; end-of-search date: September 1, 2023), and a quality assessment was performed using the Methodological index for non-randomized studies. A random-effects model was used to pool the data for the meta-analyses.

RESULTS

Nineteen studies were included, reporting on 2495 patients (88 open, 1171 L-TME, 995 R-TME, and 241 TaTME). Quantitative analyses comparing L-TME vs. R-TME showed no significant differences regarding urinary and sexual functioning, except for urinary function at three months post-surgery, which favoured R-TME (SMD [CI] -0 .15 [- 0.24 to - 0.06], p = 0.02; n = 401). Qualitative analyses identified most studies did not find significant differences in urinary, sexual, and fecal functioning and QoL between different techniques.

CONCLUSIONS

This systematic review and meta-analysis highlight a significant gap in the literature concerning the evaluation of functional outcomes and QoL after TME for rectal cancer treatment. This study emphasizes the need for high-quality, randomized-controlled, and prospective cohort studies evaluating these outcomes. Based on the limited available evidence, this systematic review and meta-analysis suggests no significant differences in patients' urinary, sexual, and fecal functioning and their QoL across various TME techniques.

Dissection layer selection based on an understanding of pelvic fascial anatomy in transanal total mesorectal excision

This study aimed to review the historical transition of rectal cancer surgery and recent evidence regarding transanal total mesorectal excision (TaTME). Additionally, it outlined the anatomical landmarks and technical considerations essential for successful TaTME. Anatomical studies and surgical techniques were analyzed to identify key landmarks and procedural steps crucial for TaTME. TaTME offers improved visibility and maneuverability even in the deep and narrow pelvis and is expected to contribute to tumor radical cure rates. By securing the circumferential resection margin and distal margin while preserving pelvic autonomic nerve function, TaTME holds promise for maintaining postoperative urinary and sexual functions. Key anatomical landmarks include the endopelvic fascia posteriorly, the S4-pelvic splanchnic nerve laterally, and the prostate or posterior vaginal wall anteriorly. Selecting the appropriate dissection layer based on tumor depth and ensuring precise incision of the tendinous arch of the pelvic fascia contributes to successful TaTME outcomes. TaTME represents a significant advancement in rectal cancer surgery, offering improved outcomes through meticulous attention to anatomical detail and precise dissection techniques. Understanding the historical context of rectal cancer surgery alongside recent evidence on TaTME is essential for optimizing patient outcomes and expanding the safe implementation of this innovative approach.

Peri-operative, oncological and functional outcomes of robotic versus transanal total mesorectal excision in patients with rectal cancer: A systematic review and meta-analysis

BACKGROUND

Comparative outcomes of robotic low anterior resection (rTME) and trans-anal total mesorectal excision (TaTME) in patients with low rectal cancer were evaluated.

METHODS

A systematic online search was conducted using the following databases: PubMed, Scopus, Cochrane database, The Virtual Health Library, Clinical trials.gov and Science Direct. Comparative studies of rTME versus TaTME for low rectal cancer were included. Primary outcomes were postoperative complications, including anastomotic leak, surgical site infection, and Clavien-Dindo complication rate. Total operative time, conversion to open surgery, intra-operative blood loss, intensive therapy unit (ITU) and total hospital length of stay (LOS), oncological outcomes and functional outcomes were the other evaluated outcome parameters.

RESULTS

A total of 12 studies with a total number of 3025 patients divided between rTME (n = 1881) and TaTME (n = 1144) groups were included. There was no significant difference between the two groups for total operative time (P = 0.39), conversion to open surgery (P = 0.29) and intra-operative blood loss (P = 0.62). Clavien-Dindo ≥ 3 complication rate (P = 0.47), anastomotic leak (P = 0.89), rates of re-operation (P = 0.62) and re-admission (P = 0.92), R0 resections (P = 0.52), ITU LOS (P = 0.63) and total hospital LOS (P = 0.30) also showed similar results between the two groups. However, the rTME group had higher rates of total harvested lymph nodes (P = 0.04) and complete total mesorectal excision (TME) resections (P = 0.05). Albeit with a limited dataset, the Wexner and low anterior resection syndrome (LARS) scores showed better functional results in the rTME group compared with the TaTME group (P = 0.0009 and P = 0.00001, respectively).

CONCLUSION

Compared with TaTME, rTME seems to provide better functional outcomes, higher lymph node yield and more complete TME resections with a similar post-operative complications profile.

Robotic-assisted low anterior resection for rectal cancer shows similar clinical efficacy to laparoscopic surgery: A propensity score matched study

BACKGROUND

Rectal cancer ranks as the second leading cause of cancer-related mortality worldwide, necessitating surgical resection as the sole treatment option. Over the years, there has been a growing adoption of minimally invasive surgical techniques such as robotic and laparoscopic approaches. Robotic surgery represents an innovative modality that effectively addresses the limitations associated with traditional laparoscopic techniques. While previous studies have reported favorable perioperative outcomes for robot-assisted radical resection in rectal cancer patients, further evidence regarding its oncological safety is still warranted.

AIM

To conduct a comparative analysis of perioperative and oncological outcomes between robot-assisted and laparoscopic-assisted low anterior resection (LALAR) procedures.

METHODS

The clinical data of 125 patients who underwent robot-assisted low anterior resection (RALAR) and 279 patients who underwent LALAR resection at Shandong Provincial Hospital Affiliated to Shandong First Medical University from December 2019 to November 2022 were retrospectively analyzed. After performing a 1:1 propensity score matching, the patients were divided into two groups: The RALAR group and the LALAR group (111 cases in each group). Subsequently, a comparison was made between the short-term outcomes within 30 d after surgery and the 3-year survival outcomes of these two groups.

RESULTS

Compared to the LALAR group, the RALAR group exhibited a significantly earlier time to first flatus [2 (2-2) d vs 3 (3-3) d, P = 0.000], as well as a shorter time to first fluid diet [4 (3-4) d vs 5 (4-6) d, P = 0.001]. Additionally, the RALAR group demonstrated reduced postoperative indwelling catheter time [2 (1-3) d vs 4 (3-5) d, P = 0.000] and decreased length of hospital stay after surgery [5 (5-7) d vs 7(6-8) d, P = 0.009]. Moreover, there was an observed increase in total cost of hospitalization for the RALAR group compared to the LALAR group [10777 (10780-11850) dollars vs 10550 (8766-11715) dollars, P = 0.012]. No significant differences were found in terms of conversion rate to laparotomy or incidence of postoperative complications between both groups. Furthermore, no significant disparities were noted regarding the 3-year overall survival rate and 3-year disease-free survival rate between both groups.

CONCLUSION

Robotic surgery offers potential advantages in terms of accelerated recovery of gastrointestinal and urologic function compared to LALAR resection, while maintaining similar perioperative and 3-year oncological outcomes.

Long-term restoration of bowel continuity after rectal cancer resection and the influence of surgical technique: A nationwide cross-sectional study

AIM

Literature on nationwide long-term permanent stoma rates after rectal cancer resection in the minimally invasive era is scarce. The aim of this population-based study was to provide more insight into the permanent stoma rate with interhospital variability (IHV) depending on surgical technique, with pelvic sepsis, unplanned reinterventions and readmissions as secondary outcomes.

METHOD

Patients who underwent open or minimally invasive resection of rectal cancer (lower border below the sigmoid take-off) in 67 Dutch centres in 2016 were included in this cross-sectional cohort study.

RESULTS

Among 2530 patients, 1470 underwent a restorative resection (58%), 356 a Hartmann's procedure (14%, IHV 0%-42%) and 704 an abdominoperineal resection (28%, IHV 3%-60%). Median follow-up was 51 months. The overall permanent stoma rate at last follow-up was 50% (IHV 13%-79%) and the unintentional permanent stoma rate, permanent stoma after a restorative procedure or an unplanned Hartmann's procedure, was 11% (IHV 0%-29%). A total of 2165 patients (86%) underwent a minimally invasive resection: 1760 conventional (81%), 170 transanal (8%) and 235 robot-assisted (11%). An anastomosis was created in 59%, 80% and 66%, with corresponding unintentional permanent stoma rates of 12%, 24% and 14% (p = 0.001), respectively. When corrected for age, American Society of Anesthesiologists classification, cTNM, distance to the anorectal junction and neoadjuvant (chemo)radiotherapy, the minimally invasive technique was not associated with an unintended permanent stoma (p = 0.071) after a restorative procedure.

CONCLUSION

A remarkable IHV in the permanent stoma rate after rectal cancer resection was found. No beneficial influence of transanal or robot-assisted laparoscopy on the unintentional permanent stoma rate was found, although this might be caused by the surgical learning curve. A reduction in IHV and improving preoperative counselling for decision-making for restorative procedures are required.

Conversion rate to open surgery during transanal total mesorectal excision (TaTME) for rectal cancer: a single-center experience

Minimally invasive techniques for rectal cancer have demonstrated considerable advantages in terms of faster recovery and less post-operative complications. However, due to the complex anatomy and a limited surgical field, conversion to open surgery is still sometimes required, with a negative impact on the short-and long-term outcomes. The purpose of this study was to analyse the conversion rate to open abdominal surgery during laparoscopic transanal total mesorectal excision (TaTME) procedures performed at a high-volume Italian referral center. All consecutive TaTME performed for mid-to-low rectal cancer between 2015 and 2023 were reviewed, independently if treated with a primary anastomosis (with/without a diverting ostomy) or an end stoma. All procedures were performed using a standardized approach by the same surgical team. Patients with benign diagnosis that underwent different-from rectal resection procedures and cases pre-operatively scheduled for open surgery were excluded. The primary outcome of interest was the rate of conversion, defined as an un-planned intraoperative switch to open surgery using a midline laparotomy. Secondary aims included the comparison of patients who had a longer vs shorter operative time. Out of 220 patients, 210 were selected. In 187 cases, a primary anastomosis was performed, while 23 patients received a terminal colostomy (1 in the converted group; 22 in the full MIS- TaTME group, 10.6%). A surgical approach modification occurred in two cases, with a conversion rate of 0.95%. Median operative time was 281 min. Reasons for conversions included intra-operative difficulties impairing the mini-invasive procedure without intra-operative complications in one case, and difficulties in the laparoscopic control of an intraoperative bleeding due to a splenic lesion in another patient. Male sex and a higher BMI were found to be statistically significantly associated to longer operative time (respectively: p = 0.001 and p = 0.0025). In a high-volume center, a standardized TaTME is associated to a low conversion rate to open abdominal surgery.

Robotic, transanal, and laparoscopic total mesorectal excision for locally advanced mid/low rectal cancer: European multicentre, propensity score-matched study

BACKGROUND

Total mesorectal excision (TME) is the standard surgery for low/mid locally advanced rectal cancer. The aim of this study was to compare three minimally invasive surgical approaches for TME with primary anastomosis (laparoscopic TME, robotic TME, and transanal TME).

METHODS

Records of patients undergoing laparoscopic TME, robotic TME, or transanal TME between 2013 and 2022 according to standardized techniques in expert centres contributing to the European MRI and Rectal Cancer Surgery III (EuMaRCS-III) database were analysed. Propensity score matching was applied to compare the three groups with respect to the complication rate (primary outcome), conversion rate, postoperative recovery, and survival.

RESULTS

A total of 468 patients (mean(s.d.) age of 64.1(11) years) were included; 190 (40.6%) patients underwent laparoscopic TME, 141 (30.1%) patients underwent robotic TME, and 137 (29.3%) patients underwent transanal TME. Comparative analyses after propensity score matching demonstrated a higher rate of postoperative complications for laparoscopic TME compared with both robotic TME (OR 1.80, 95% c.i. 1.11-2.91) and transanal TME (OR 2.87, 95% c.i. 1.72-4.80). Robotic TME was associated with a lower rate of grade A anastomotic leakage (2%) compared with both laparoscopic TME (8.8%) and transanal TME (8.1%) (P = 0.031). Robotic TME (1.4%) and transanal TME (0.7%) were both associated with a lower conversion rate to open surgery compared with laparoscopic TME (8.8%) (P < 0.001). Time to flatus and duration of hospital stay were shorter for patients treated with transanal TME (P = 0.003 and 0.001 respectively). There were no differences in operating time, intraoperative complications, blood loss, mortality, readmission, R0 resection, or survival.

CONCLUSION

In this multicentre, retrospective, propensity score-matched, cohort study of patients with locally advanced rectal cancer, newer minimally invasive approaches (robotic TME and transanal TME) demonstrated improved outcomes compared with laparoscopic TME.

Management of acute and chronic pelvic sepsis after total mesorectal excision for rectal cancer-a 10-year experience of a national referral centre

AIM

Uncontrolled pelvic sepsis following rectal cancer surgery may lead to dramatic consequences with significant impact on patients' quality of life. The aim of this retrospective observational study is to evaluate management of pelvic sepsis after total mesorectal excision for rectal cancer at a national referral centre.

METHOD

Referred patients with acute or chronic pelvic sepsis after sphincter preserving rectal cancer resection, with the year of referral between 2010 and 2014 (A) or between 2015 and 2020 (B), were included. The main outcome was control of pelvic sepsis at the end of follow-up, with healed anastomosis with restored faecal stream (RFS) as co-primary outcome.

RESULTS

In total 136 patients were included: 49 in group A and 87 in group B. After a median follow-up of 82 months (interquartile range 35-100) in group A and 42 months (interquartile range 22-60) in group B, control of pelvic sepsis was achieved in all patients who received endoscopic vacuum assisted surgical closure (7/7 and 2/2), in 91% (19/21) and 89% (31/35) of patients who received redo anastomosis (P = 1.000) and in 100% (18/18) and 95% (41/43) of patients who received intersphincteric resection (P = 1.000), respectively. Restorative procedures resulted in a healed anastomosis with RFS in 61% (17/28) of patients in group A and 68% (25/37) of patients in group B (P = 0.567).

CONCLUSION

High rates of success can be achieved with surgical salvage of pelvic sepsis in a dedicated tertiary referral centre, without significant differences over time. In well selected and motivated patients a healed anastomosis with RFS can be achieved in the majority.

Is survival after transanal total mesorectal excision (taTME) worse than that after traditional total mesorectal excision? A retrospective propensity score-adjusted cohort study

PURPOSE

Transanal total mesorectal excision (taTME) was developed to provide better vision during resection of the mesorectum. Conflicting results have shown an increase in local recurrence and shorter survival after taTME. This study compared the outcomes of taTME and abdominal (open, laparoscopic, robotic) total mesorectal excision (abTME).

METHODS

Patients who underwent taTME or abTME for stages I-III rectal cancer and who received an anastomosis were included. A retrospective analysis of a prospectively conducted database was performed. The primary endpoints were overall survival (OS), cancer-specific survival (CSS), and disease-free survival (DFS). Risk factors were adjusted by propensity score matching (PSM). The secondary endpoints were local recurrence rates and combined poor pathological outcomes.

RESULTS

From 2012 to 2020, a total of 189 patients underwent taTME, and 119 underwent abTME; patients were followed up for a mean of 54.7 (SD 24.2) and 78.4 (SD 34.8) months, respectively (p < 0.001). The 5-year survival rates after taTME and abTME were not significantly different after PSM: OS: 78.2% vs. 88.6% (p = 0.073), CSS: 87.4% vs. 92.1% (p = 0.359), and DFS: 69.3% vs. 80.9% (p = 0.104), respectively. No difference in the local recurrence rate was observed (taTME, n = 10 (5.3%); abTME, n = 10 (8.4%); p = 0.280). Combined poor pathological outcomes were more frequent after abTME (n = 36, 34.3%) than after taTME (n = 35, 19.6%) (p = 0.006); this difference was nonsignificant according to multivariate analysis (p = 0.404).

CONCLUSION

taTME seems to be a good treatment option for patients with rectal cancer and is unlikely to significantly affect local recurrence or survival. However, further investigations concerning the latter are warranted.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT0496910).

Permanent stoma rate and long-term stoma complications in laparoscopic, robot-assisted, and transanal total mesorectal excisions: a retrospective cohort study

BACKGROUND

The surgical resection of rectal carcinoma is associated with a high risk of permanent stoma rate. Primary anastomosis rate is suggested to be higher in robot-assisted and transanal total mesorectal excision, but permanent stoma rate is unknown.

METHODS

Patients undergoing total mesorectal excision for MRI-defined rectal cancer between 2015 and 2017 in 11 centers highly experienced in laparoscopic, robot-assisted or transanal total mesorectal excision were included in this retrospective study. Permanent stoma rate, stoma-related complications, readmissions, and reoperations were registered. A multivariable regression analysis was performed for permanent stoma rate, stoma-related complications, and stoma-related reoperations.

RESULTS

In total, 1198 patients were included. Permanent stoma rate after low anterior resection (with anastomosis or with an end colostomy) was 40.1% in patients undergoing laparoscopic surgery, 21.3% in patients undergoing robot-assisted surgery, and 25.6% in patients undergoing transanal surgery (P < 0.001). Permanent stoma rate after low anterior resection with an anastomosis was 17.3%, 11.8%, and 15.1%, respectively. The robot-assisted and transanal techniques were independently associated with a reduction in permanent stoma rate in patients who underwent a low anterior resection (with anastomosis or with an end colostomy) (OR 0.39 [95% CI 0.25, 0.59] and OR 0.35 [95% CI 0.22, 0.55]), while this was not seen in patients who underwent a restorative low anterior resection. 45.4% of the patients who had a stoma experienced stoma-related complications, 4.0% were at least once readmitted, and 8.9% underwent at least one reoperation.

CONCLUSIONS

The robot-assisted and transanal techniques are associated with a lower permanent stoma rate in patients who underwent a low anterior resection.

The role of transanal compared to laparoscopic total mesorectal excision (taTME vs. lapTME) for the treatment of mid-low rectal cancer in obese patients: outcomes of a multicenter propensity-matched analysis

To compare the rate of sphincter-saving interventions between transanal and laparoscopic Total Mesorectal Excision in this particular group of patients. A multicentre observational study was conducted using a prospective database, including patients diagnosed with rectal cancer below the peritoneal reflection and BMI ≥ 30 kg/m2, who underwent minimally invasive elective surgery over a 5-year period. Exclusion criteria were (1) sphincter and/or puborectalis invasion; (2) multi-visceral resections; (3) palliative surgeries. The study population was divided into two groups according to the intervention: transanal or laparoscopic total mesorectal excision. The primary outcome was the rate of sphincter-saving surgery. Secondary outcomes included conversion, postoperative complications, quality of the specimen, and survival. A total of 93 patients were included; 40 (43%) transanal total mesorectal excision were compared to 53 (57%) laparoscopic. In addition, 35 cases of transanal approach were case-matched with an equal number of laparoscopic approaches, based on gender, tumor's height, and neoadjuvant therapy. In both groups, 43% of the patients had low rectal cancer; however, the rate of sphincter-saving surgery was significantly higher in the transanal group (97% vs. 71%, p = 0.003). There were no conversions to open surgery in the transanal group, compared to 2 cases in the laparoscopic group (6%) (p = 0.246). The percentage of major complications was similar, including the rate of anastomotic leakage (10% transanal vs. 19% laparoscopic, p = 0.835). In our experience, higher percentages of sphincter-saving procedures and lower conversion rates are potential benefits of using the transanal approach in a complex surgical setting population of obese patients with mid-low rectal tumors when compared to laparoscopic.

Multicenter phase II trial of transanal total mesorectal excision for rectal cancer: preliminary results

BACKGROUND

Transanal TME (taTME) combines abdominal and transanal dissection to facilitate sphincter preservation in patients with low rectal tumors. Few phase II/III trials report long-term oncologic and functional results. We report early results from a North American prospective multicenter phase II trial of taTME (NCT03144765).

METHODS

100 patients with stage I-III rectal adenocarcinoma located ≤ 10 cm from the anal verge (AV) were enrolled across 11 centers. Primary and secondary endpoints were TME quality, pathologic outcomes, 30-day and 90-day outcomes, and stoma closure rate. Univariable regression analysis was performed to assess risk factors for incomplete TME and anastomotic complications.

RESULTS

Between September 2017 and April 2022, 70 males and 30 females with median age of 58 (IQR 49-62) years and BMI 27.8 (IQR 23.9-31.8) kg/m2 underwent 2-team taTME for tumors located a median 5.8 (IQR 4.5-7.0) cm from the AV. Neoadjuvant radiotherapy was completed in 69%. Intersphincteric resection was performed in 36% and all patients were diverted. Intraoperative complications occurred in 8% including 3 organ injuries, 2 abdominal and 1 transanal conversion. The 30-day and 90-day morbidity rates were 49% (Clavien-Dindo (CD) ≥ 3 in 28.6%) and 56% (CD ≥ 3 in 30.4% including 1 mortality), respectively. Anastomotic complications were reported in 18% including 10% diagnosed within 30 days. Higher anastomotic risk was noted among males (p = 0.05). At a median follow-up of 5 (IQR 3.1-7.4) months, 98% of stomas were closed. TME grade was complete or near complete in 90%, with positive margins in 2 cases (3%). Risk factors for incomplete TME were ASA ≥ 3 (p = 0.01), increased time between NRT and surgery (p = 0.03), and higher operative blood loss (p = 0.003).

CONCLUSION

When performed at expert centers, 2-team taTME in patients with low rectal tumors is safe with low conversion rates and high stoma closure rate. Mid-term results will further evaluate oncologic and functional outcomes.

Tumour, narrow pelvis and surgery specific factors for total mesorectal excision quality and morbidity following rectal cancer resection

BACKGROUND

Pelvic anatomy is critical in challenging rectal resections. This study investigated how pelvic anatomy relates to total mesorectal excision (TME) quality, anastomotic leakage rate, and long-term oncological outcomes.

METHODS

Patients undergoing elective rectal cancer resection from 2008 to 2017 in an Austrian institution were retrospectively reviewed regardless of the surgical approach. CT scans were analysed for pelvic measurements and volumes. The primary outcomes of interest were the correlation between pelvic dimensions and the TME quality and anastomotic leakage. Subanalysis was done by surgical approach (open, laparoscopic, transanal TME). Secondary outcomes were overall and disease-free survivals.

RESULTS

Among 154 eligible patients, 112 were included. The angle between pubic symphysis and promontory significantly correlated with worse TME grades (TME grade 1: mean(s.d.) 102.7(5.7)°; TME grade 2: 92.0(4.4)°; TME grade 3: 91.4(3.6)°; P < 0.001). A significantly lower distance between tumour and circumferential resection margin (CRM) was observed in grade 3 resections, whereas no difference appeared in grade 1 and grade 2 resection (TME grade 1: mean(s.d.) 11.92(9.4) mm; TME grade 2: 10.8(8.1) mm; TME grade 3: 3.1(4.1) mm; P = 0.003). The anastomotic leakage rate was significantly higher in case of a lower CRM (patients with anastomotic leakage: mean(s.d.) 6.8(5.8) mm versus others: 12.6(9.8) mm, P = 0.027), but not associated with pelvimetry measurements. The transanal TME (TaTME) subgroup displayed a wider angle between the pubic symphysis and promontory, younger age and improved TME quality compared to others (respectively, mean TME grades in TaTME versus open versus laparoscopic: 1.0 ± 0.0, 1.5 ± 0.7 and 1.3 ± 0.5, P = 0.013). Finally, oncological survival was not impacted by pelvic measurements or worse TME quality.

CONCLUSION

The angle between the pubic symphysis and promontory and the distance between tumour and CRM were associated with worse TME grades. The anastomotic leakage was associated with a lower CRM but not with pelvimetric measures.

Completion Total Mesorectal Excision: A Case-Matched Comparison With Primary Resection

Objectives

The aim of this study was to compare the perioperative and oncological results of completion total mesorectal excision (cTME) versus primary total mesorectal excision (pTME).

Background

Early-stage rectal cancer can be treated by local excision alone, which is associated with less surgical morbidity and improved functional outcomes compared with radical surgery. When high-risk histological features are present, cTME is indicated, with possible worse clinical and oncological outcomes compared to pTME.

Methods

This retrospective cohort study included all patients that underwent TME surgery for rectal cancer performed in 11 centers in the Netherlands between 2015 and 2017. After case-matching, we compared cTME with pTME. The primary outcome was major postoperative morbidity. Secondary outcomes included the rate of restorative procedures and 3-year oncological outcomes.

Results

In total 1069 patients were included, of which 35 underwent cTME. After matching (1:2 ratio), 29 cTME and 58 pTME were analyzed. No differences were found for major morbidity (27.6% vs 19.0%; P = 0.28) and abdominoperineal excision rate (31.0% vs 32.8%; P = 0.85) between cTME and pTME, respectively. Local recurrence (3.4% vs 8.6%; P = 0.43), systemic recurrence (3.4% vs 12.1%; P = 0.25), overall survival (93.1% vs 94.8%; P = 0.71), and disease-free survival (89.7% vs 81.0%; P = 0.43) were comparable between cTME and pTME.

Conclusions

cTME is not associated with higher major morbidity, whereas the abdominoperineal excision rate and 3-year oncological outcomes are similar compared to pTME. Local excision as a diagnostic tool followed by completion surgery for early rectal cancer does not compromise outcomes and should still be considered as the treatment of early-stage rectal cancer.

Fluorescence-guided Two-port Robotic Gastrectomy Versus Conventional Laparoscopic Gastrectomy: A Nonrandomized Controlled Trial

Objective

To compare the number of retrieved lymph nodes between conventional laparoscopic gastrectomy (CLG) and robotic gastrectomy integrated with fluorescence guidance and a two-port system (integrated robotic gastrectomy, IRG).

Background

The benefits of robotic surgery over laparoscopic surgery for gastric cancer have not yet been established. Using built-in features of robotic system, further benefit can be provided to the patients with effective lymphadenectomy and enhanced recovery.

Methods

A nonrandomized controlled trial was performed by a single surgeon at single-center, tertiary referral hospital between January 2018 and October 2021. Overall, 140 patients scheduled to undergo minimally invasive subtotal gastrectomy for early gastric cancer were enrolled. The primary endpoint was the number of retrieved lymph nodes. Secondary endpoints were complications, hospital stay, pain score, body image, and operative cost.

Results

This study analyzed 124 patients in the per-protocol group (IRG, 64; CLG, 60). The number of retrieved lymph nodes was higher in the IRG group than those in the CLG group (IRG vs CLG; 42.1 ± 17.9 vs 35.1 ± 14.6, P = 0.019). Moreover, other surgical parameters, such as hospital stay (4.1 ± 1.0 vs 5.2 ± 1.8, P < 0.001) and body image scale (better in 4 of the 10 questions), were significantly better in the IRG than in the CLG.

Conclusions

Robotic surgical procedures integrated with fluorescence guidance and a reduced-port system yielded more retrieved lymph nodes. In addition, the IRG group showed better perioperative surgical outcomes, particularly regarding the length of hospital stay and postoperative body image.

Trial registration

NCT03396354.

Economic analysis of open versus laparoscopic versus robot-assisted versus transanal total mesorectal excision in rectal cancer patients: A systematic review

OBJECTIVES

Minimally invasive total mesorectal excision is increasingly being used as an alternative to open surgery in the treatment of patients with rectal cancer. This systematic review aimed to compare the total, operative and hospitalization costs of open, laparoscopic, robot-assisted and transanal total mesorectal excision.

METHODS

This systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement (PRISMA) (S1 File) A literature review was conducted (end-of-search date: January 1, 2023) and quality assessment performed using the Consensus Health Economic Criteria.

RESULTS

12 studies were included, reporting on 2542 patients (226 open, 1192 laparoscopic, 998 robot-assisted and 126 transanal total mesorectal excision). Total costs of minimally invasive total mesorectal excision were higher compared to the open technique in the majority of included studies. For robot-assisted total mesorectal excision, higher operative costs and lower hospitalization costs were reported compared to the open and laparoscopic technique. A meta-analysis could not be performed due to low study quality and a high level of heterogeneity. Heterogeneity was caused by differences in the learning curve and statistical methods used.

CONCLUSION

Literature regarding costs of total mesorectal excision techniques is limited in quality and number. Available evidence suggests minimally invasive techniques may be more expensive compared to open total mesorectal excision. High-quality economical evaluations, accounting for the learning curve, are needed to properly assess costs of the different techniques.

A systematic review and meta-analysis of minimally invasive total mesorectal excision versus transanal total mesorectal excision for mid and low rectal cancer

Background

Minimally invasive total mesorectal excision (MiTME) and transanal total mesorectal excision (TaTME) are popular trends in mid and low rectal cancer. However, there is currently no systematic comparison between MiTME and TaTME of mid and low-rectal cancer. Therefore, we systematically study the perioperative and pathological outcomes of MiTME and TaTME in mid and low rectal cancer.

Methods

We have searched the Embase, Cochrane Library, PubMed, Medline, and Web of Science for articles on MiTME (robotic or laparoscopic total mesorectal excision) and TaTME (transanal total mesorectal excision). We calculated pooled standard mean difference (SMD), relative risk (RR), and 95% confidence intervals (CIs). The protocol for this review has been registered on PROSPERO (CRD42022374141).

Results

There are 11010 patients including 39 articles. Compared with TaTME, patients who underwent MiTME had no statistical difference in operation time (SMD -0.14; CI -0.31 to 0.33; I²⁼84.7%, P=0.116), estimated blood loss (SMD 0.05; CI -0.05 to 0.14; I²⁼48%, P=0.338), postoperative hospital stay (RR 0.08; CI -0.07 to 0.22; I²⁼0%, P=0.308), over complications (RR 0.98; CI 0.88 to 1.08; I²⁼25.4%, P=0.644), intraoperative complications (RR 0.94; CI 0.69 to 1.29; I²⁼31.1%, P=0.712), postoperative complications (RR 0.98; CI 0.87 to 1.11; I²⁼16.1%, P=0.789), anastomotic stenosis (RR 0.85; CI 0.73 to 0.98; I²⁼7.4%, P=0.564), wound infection (RR 1.08; CI 0.65 to 1.81; I²⁼1.9%, P=0.755), circumferential resection margin (RR 1.10; CI 0.91 to 1.34; I²⁼0%, P=0.322), distal resection margin (RR 1.49; CI 0.73 to 3.05; I²⁼0%, P=0.272), major low anterior resection syndrome (RR 0.93; CI 0.79 to 1.10; I²⁼0%, P=0.386), lymph node yield (SMD 0.06; CI -0.04 to 0.17; I²⁼39.6%, P=0.249), 2-year DFS rate (RR 0.99; CI 0.88 to 1.11; I²⁼0%, P = 0.816), 2-year OS rate (RR 1.00; CI 0.90 to 1.11; I²⁼0%, P = 0.969), distant metastasis rate (RR 0.47; CI 0.17 to 1.29; I²⁼0%, P = 0.143), and local recurrence rate (RR 1.49; CI 0.75 to 2.97; I²⁼0%, P = 0.250). However, patients who underwent MiTME had fewer anastomotic leak rates (SMD -0.38; CI -0.59 to -0.17; I²⁼19.0%, P<0.0001).

Conclusion

This study comprehensively and systematically evaluated the safety and efficacy of MiTME and TaTME in the treatment of mid to low-rectal cancer through meta-analysis. There is no difference between the two except for patients with MiTME who have a lower anastomotic leakage rate, which provides some evidence-based reference for clinical practice. Of course, in the future, more scientific and rigorous conclusions need to be drawn from multi-center RCT research.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO, identifier CRD42022374141.

Impact of the approach on conversion to open surgery during minimally invasive restorative total mesorectal excision for rectal cancer

BACKGROUND

The aim of this study is to explore the impact of the approach on conversion in patients undergoing minimally invasive restorative total mesorectal excision within a single unit.

METHODS

A retrospective cohort study was conducted. Patients with rectal cancer undergoing minimally invasive restorative total mesorectal excision between January 2006 and June 2020 were included. Subjects were classified according to the presence or absence of conversion. Baseline variables and short-term outcomes were compared. Regression analyses were conducted to assess the relationship between the approach and conversion.

RESULTS

During the study period, 318 patients underwent a restorative proctectomy. Of these, 240 met the inclusion criteria. Robotic and laparoscopic approaches were undertaken in 147 (61.3%) and 93 (38.8%) cases, respectively. A transanal approach was utilised in 62 (25.8%) cases (58.1% in combination with a robotic transabdominal approach). Conversion to open surgery occurred in 30 cases (12.5%). Conversion was associated with an increased overall complication rate (P = 0.003), surgical complications (P = 0.009), superficial surgical site infections (P = 0.02) and an increased length of hospital stay (P = 0.006). Robotic and transanal approaches were both associated with decreased conversion rates. The multiple logistic regression analysis, however, showed that only a transanal approach was independently associated with a lower risk of conversion (OR 0.147, 0.023-0.532; P = 0.01), whilst obesity was an independent risk factor for conversion (OR 4.388, 1.852-10.56; P < 0.00).

CONCLUSIONS

A transanal component is associated with a reduced conversion rate in minimally invasive restorative total mesorectal excision, regardless of the transabdominal approach utilised. Larger studies will be required to confirm these findings and define which subgroup of patients could benefit from transanal component when a robotic approach is undertaken.

Impact of a diverting ileostomy in total mesorectal excision with primary anastomosis for rectal cancer

BACKGROUND

The role of diverting ileostomy in total mesorectal excision (TME) for rectal cancer with primary anastomosis is debated. The aim of this study is to gain insight in the clinical consequences of a diverting ileostomy, with respect to stoma rate at one year and stoma-related morbidity.

METHODS

Patients undergoing TME with primary anastomosis for rectal cancer between 2015 and 2017 in eleven participating hospitals were included. Retrospectively, two groups were compared: patients with or without diverting ileostomy construction during primary surgery. Primary endpoint was stoma rate at one year. Secondary endpoints were severity and rate of anastomotic leakage, overall morbidity rate within thirty days and stoma (reversal) related morbidity.

RESULTS

In 353 out of 595 patients (59.3%) a diverting ileostomy was constructed during primary surgery. Stoma rate at one year was 9.9% in the non-ileostomy group and 18.7% in the ileostomy group (p = 0.003). After correction for confounders, multivariate analysis showed that the construction of a diverting ileostomy during primary surgery was an independent risk factor for stoma at one year (OR 2.563 (95%CI 1.424-4.611), p = 0.002). Anastomotic leakage rate was 17.8% in the non-ileostomy group and 17.2% in the ileostomy group (p = 0.913). Overall 30-days morbidity rate was 37.6% in the non-ileostomy group and 56.1% in the ileostomy group (p < 0.001). Stoma reversal related morbidity rate was 17.9%.

CONCLUSIONS

The stoma rate at one year was higher in patients with ileostomy construction during primary surgery. The incidence and severity of anastomotic leakage were not reduced by construction of an ileostomy. The morbidity related to the presence and reversal of a diverting ileostomy was substantial.

A Cost Overview of Minimally Invasive Total Mesorectal Excision in Rectal Cancer Patients: A Population-based Cohort in Experienced Centres

Background

Total mesorectal excision has been the gold standard for the operative management of rectal cancer. The most frequently used minimally invasive techniques for surgical resection of rectal cancer are laparoscopic, robot-assisted, and transanal total mesorectal excision. As studies comparing the costs of the techniques are lacking, this study aims to provide a cost overview.

Method

This retrospective cohort study included patients who underwent total mesorectal resection between 2015 and 2017 at 11 dedicated centers, which completed the learning curve of the specific technique. The primary outcome was total in-hospital costs of each technique up to 30 days after surgery including all major surgical cost drivers, while taking into account different team approaches in the transanal approach. Secondary outcomes were hospitalization and complication rates. Statistical analysis was performed using multivariable linear regression analysis.

Results

In total, 949 patients were included, consisting of 446 laparoscopic (47%), 306 (32%) robot-assisted, and 197 (21%) transanal total mesorectal excisions. Total costs were significantly higher for transanal and robot-assisted techniques compared to the laparoscopic technique, with median (interquartile range) for laparoscopic, robot-assisted, and transanal at €10,556 (8,642;13,829), €12,918 (11,196;16,223), and € 13,052 (11,330;16,358), respectively (P < 0.001). Also, the one-team transanal approach showed significant higher operation time and higher costs compared to the two-team approach. Length of stay and postoperative complications did not differ between groups.

Conclusion

Transanal and robot-assisted approaches show higher costs during 30-day follow-up compared to laparoscopy with comparable short-term clinical outcomes. Two-team transanal approach is associated with lower total costs compared to the transanal one-team approach.

Surgical Outcomes, Long-Term Recurrence Rate, and Resource Utilization in a Prospective Cohort of 165 Patients Treated by Transanal Total Mesorectal Excision for Distal Rectal Cancer

A transanal total mesorectal excision (taTME) is a smart alternative to a conventional TME. However, worrisome reports of a high recurrence and complications triggered a moratorium in a few countries. This study assessed the outcomes and resource utilization of a taTME. Consecutive patients with distal rectal cancer treated by a taTME were prospectively included. Outcomes were reported as the median and interquartile range (IQR). One hundred sixty-five patients (67% male and 33% female) with a tumor 7 cm (IQR 5-10) from the anal verge were followed for 50 months (IQR 32-79). The resection margins were threatened in 25% of the patients, while 75% of the patients received neoadjuvant radiochemotherapy. A good mesorectal dissection and clear margins were achieved in 96% of the specimens, and 27 lymph nodes (IQR 20-38) were harvested. Ninety-day major morbidity affected 36 patients (21.8%), including 12 with anastomotic leakages (7.2%). A recurrence occurred locally in 9 patients (5.4%), and 44 patients had a distant metastasis (26.7%). The five-year disease-free survival and overall survival were 67% and 90%, respectively. A multivariate analysis found a long operation and frailty predicted an anastomotic leak, while a positive distal margin and lymph nodes predicted a local recurrence and distant metastasis. A two-team taTME saved 102 min of operative time and EUR 1385 when compared to a one-team approach. Transanal total mesorectal excision produced sound surgical quality and excellent oncologic outcomes.

Assessing the learning curve of robot-assisted total mesorectal excision: a multicenter study considering procedural safety, pathological safety, and efficiency

PURPOSE

Evidence regarding the learning curve of robot-assisted total mesorectal excision is scarce and of low quality. Case-mix is mostly not taken into account, and learning curves are based on operative time, while preferably clinical outcomes and literature-based limits should be used. Therefore, this study aims to assess the learning curve of robot-assisted total mesorectal excision.

METHODS

A retrospective study was performed in four Dutch centers. The primary aim was to assess the safety of the individual and institutional learning curves using a RA-CUSUM analysis based on intraoperative complications, major postoperative complications, and compound pathological outcome (positive circumferential margin or incomplete TME specimen). The learning curve for efficiency was assessed using a LC-CUSUM analysis for operative time. Outcomes of patients before and after the learning curve were compared.

RESULTS

In this study, seven participating surgeons performed robot-assisted total mesorectal excisions in 531 patients. Learning curves for intraoperative complications, postoperative complications, and compound pathological outcome did not exceed predefined literature-based limits. The LC-CUSUM for operative time showed lengths of the learning curve ranging from 12 to 35 cases. Intraoperative, postoperative, and pathological outcomes did not differ between patients operated during and after the learning curve.

CONCLUSION

The learning curve of robot-assisted total mesorectal excision based on intraoperative complications, postoperative complications, and compound pathological outcome did not exceed predefined limits and is therefore suggested to be safe. Using operative time as a surrogate for efficiency, the learning curve is estimated to be between 12 and 35 procedures.

Implementation of robotic rectal cancer surgery: a cross-sectional nationwide study

AIM

An increasing number of centers have implemented a robotic surgical program for rectal cancer. Several randomized controls trials have shown similar oncological and postoperative outcomes compared to standard laparoscopic resections. While introducing a robot rectal resection program seems safe, there are no data regarding implementation on a nationwide scale. Since 2018 robot resections are separately registered in the mandatory Dutch Colorectal Audit. The present study aims to evaluate the trend in the implementation of robotic resections (RR) for rectal cancer relative to laparoscopic rectal resections (LRR) in the Netherlands between 2018 and 2020 and to compare the differences in outcomes between the operative approaches.

METHODS

Patients with rectal cancer who underwent surgical resection between 2018 and 2020 were selected from the Dutch Colorectal Audit. The data included patient characteristics, disease characteristics, surgical procedure details, postoperative outcomes. The outcomes included any complication within 90 days after surgery; data were categorized according to surgical approach.

RESULTS

Between 2018 and 2020, 6330 patients were included in the analyses. 1146 patients underwent a RR (18%), 3312 patients a LRR (51%), 526 (8%) an open rectal resection, 641 a TaTME (10%), and 705 had a local resection (11%). The proportion of males and distal tumors was higher in the RR compared to the LRR. Over time, the proportion of robotic procedures increased from 15% (95% confidence intervals (CI) 13-16%) in 2018 to 22% (95% CI 20-24%) in 2020. Conversion rate was lower in the robotic group [4% (95% CI 3-5%) versus 7% (95% CI 6-8%)]. Anastomotic leakage rate was similar with 16%. Defunctioning ileostomies were more common in the RR group [42% (95% CI 38-46%) versus 29% (95% CI 26-31%)].

CONCLUSION

Rectal resections are increasingly being performed through a robot-assisted approach in the Netherlands. The proportion of males and low rectal cancers was higher in RR compared to LRR. Overall outcomes were comparable, while conversion rate was lower in RR, the proportion of defunctioning ileostomies was higher compared to LRR.

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.

Comparison of three-year oncological results after restorative low anterior resection, non-restorative low anterior resection and abdominoperineal resection for rectal cancer

INTRODUCTION

Oncological outcome might be influenced by the type of resection in total mesorectal excision (TME) for rectal cancer. The aim was to see if non-restorative LAR would have worse oncological outcome. A comparison was made between non-restorative low anterior resection (NRLAR), restorative low anterior resection (RLAR) and abdominoperineal resection (APR).

MATERIALS AND METHODS

This retrospective cohort included data from patients undergoing TME for rectal cancer between 2015 and 2017 in eleven Dutch hospitals. A comparison was made for each different type of procedure (APR, NRLAR or RLAR). Primary outcome was 3-year overall survival (OS). Secondary outcomes included 3-year disease-free survival (DFS) and 3-year local recurrence (LR) rate.

RESULTS

Of 998 patients 363 underwent APR, 132 NRLAR and 503 RLAR. Three-year OS was worse after NRLAR (78.2%) compared to APR (86.3%) and RLAR (92.2%, p < 0.001). This was confirmed in a multivariable Cox regression analysis (HR 1.85 (1.07, 3.19), p = 0.03). The 3-year DFS was also worse after NRLAR (60.3%), compared to APR (70.5%) and RLAR (80.1%, p < 0.001), HR 2.05 (1.42, 2.97), p < 0.001. The LR rate was 14.6% after NRLAR, 5.2% after APR and 4.8% after RLAR (p = 0.005), HR 3.22 (1.61, 6.47), p < 0.001.

CONCLUSION

NRLAR might be associated with worse 3-year OS, DFS and LR rate compared to RLAR and APR.

Prospective multicentre observational cohort to assess quality of life, functional outcomes and cost-effectiveness following minimally invasive surgical techniques for rectal cancer in 'dedicated centres' in the Netherlands (VANTAGE trial): a protocol

INTRODUCTION

Total mesorectal excision is the standard of care for rectal cancer, which can be performed using open, laparoscopic, robot-assisted and transanal technique. Large prospective (randomised controlled) trials comparing these techniques are lacking, do not take into account the learning curve and have short-term or long-term oncological results as their primary endpoint, without addressing quality of life, functional outcomes and cost-effectiveness. Comparative data with regard to these outcomes are necessary to identify the optimal minimally invasive technique and provide guidelines for clinical application.

METHODS AND ANALYSIS

This trial will be a prospective observational multicentre cohort trial, aiming to compare laparoscopic, robot-assisted and transanal total mesorectal excision in adult patients with rectal cancer performed by experienced surgeons in dedicated centres. Data collection will be performed in collaboration with the prospective Dutch ColoRectal Audit and the Prospective Dutch ColoRectal Cancer Cohort. Quality of life at 1 year postoperatively will be the primary outcome. Functional outcomes, cost-effectiveness, short-term outcomes and long-term oncological outcomes will be the secondary outcomes. In total, 1200 patients will be enrolled over a period of 2 years in 26 dedicated centres in the Netherlands. The study is registered at https://www.trialregister.nl/9734 (NL9734).

ETHICS AND DISSEMINATION

Data will be collected through collaborating parties, who already obtained approval by their medical ethical committee. Participants will be included in the trial after having signed informed consent. Results of this study will be disseminated to participating centres, patient organisations, (inter)national society meetings and peer-reviewed journals.

Local recurrence of robot-assisted total mesorectal excision: a multicentre cohort study evaluating the initial cases

PURPOSE

Evidence regarding local recurrence rates in the initial cases after implementation of robot-assisted total mesorectal excision is limited. This study aims to describe local recurrence rates in four large Dutch centres during their initial cases.

METHODS

Four large Dutch centres started with the implementation of robot-assisted total mesorectal excision in respectively 2011, 2012, 2015, and 2016. Patients who underwent robot-assisted total mesorectal excision with curative intent in an elective setting for rectal carcinoma defined according to the sigmoid take-off were included. Overall survival, disease-free survival, systemic recurrence, and local recurrence were assessed at 3 years postoperatively. Subsequently, outcomes between the initial 10 cases, cases 11-40, and the subsequent cases per surgeon were compared using Cox regression analysis.

RESULTS

In total, 531 patients were included. Median follow-up time was 32 months (IQR: 19-50]. During the initial 10 cases, overall survival was 89.5%, disease-free survival was 73.1%, and local recurrence was 4.9%. During cases 11-40, this was 87.7%, 74.1%, and 6.6% respectively. Multivariable Cox regression did not reveal differences in local recurrence between the different case groups.

CONCLUSION

Local recurrence rate during the initial phases of implantation of robot-assisted total mesorectal procedures is low. Implementation of the robot-assisted technique can safely be performed, without additional cases of local recurrence during the initial cases, if performed by surgeons experienced in laparoscopic rectal cancer surgery.