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.

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.

Laparoscopic Versus Robot-Assisted Versus Transanal Low Anterior Resection: 3-Year Oncologic Results for a Population-Based Cohort in Experienced Centers.

BACKGROUND: Laparoscopic, robot-assisted, and transanal total mesorectal excision are the minimally invasive techniques used most for rectal cancer surgery. Because data regarding oncologic results are lacking, this study aimed to compare these three techniques while taking the learning curve into account. METHODS: This retrospective population-based study cohort included all patients between 2015 and 2017 who underwent a low anterior resection at 11 dedicated centers that had completed the learning curve of the specific technique. The primary outcome was overall survival (OS) during a 3-year follow-up period. The secondary outcomes were 3-year disease-free survival (DFS) and 3-year local recurrence rate. Statistical analysis was performed using Cox-regression. RESULTS: The 617 patients enrolled in the study included 252 who underwent a laparoscopic resection, 205 who underwent a robot-assisted resection, and 160 who underwent a transanal low anterior resection. The oncologic outcomes were equal between the three techniques. The 3-year OS rate was 90% for laparoscopic resection, 90.4% for robot-assisted resection, and 87.6% for transanal low anterior resection. The 3-year DFS rate was 77.8% for laparoscopic resection, 75.8% for robot-assisted resection, and 78.8% for transanal low anterior resection. The 3-year local recurrence rate was in 6.1% for laparoscopic resection, 6.4% for robot-assisted resection, and 5.7% for transanal procedures. Cox-regression did not show a significant difference between the techniques while taking confounders into account. CONCLUSION: The oncologic results during the 3-year follow-up were good and comparable between laparoscopic, robot-assisted, and transanal total mesorectal technique at experienced centers. These techniques can be performed safely in experienced hands.

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.

BACKGROUND: Laparoscopic total mesorectal excision (TME) surgery for rectal cancer has important technical limitations. Robot-assisted and transanal TME (TaTME) may overcome these limitations, potentially leading to lower conversion rates and reduced morbidity. However, comparative data between the three approaches are lacking. The aim of this study was to compare short-term outcomes for laparoscopic TME, robot-assisted TME and TaTME in expert centres. METHODS: Patients undergoing rectal cancer surgery between 2015 and 2017 in expert centres for laparoscopic, robot-assisted or TaTME were included. Outcomes for TME surgery performed by the specialized technique in the expert centres were compared after propensity score matching. The primary outcome was conversion rate. Secondary outcomes were morbidity and pathological outcomes. RESULTS: A total of 1078 patients were included. In rectal cancer surgery in general, the overall rate of primary anastomosis was 39.4, 61.9 and 61.9 per cent in laparoscopic, robot-assisted and TaTME centres respectively (P < 0.001). For specialized techniques in expert centres excluding abdominoperineal resection (APR), the rate of primary anastomosis was 66.7 per cent in laparoscopic, 89.8 per cent in robot-assisted and 84.3 per cent in TaTME (P < 0.001). Conversion rates were 3.7 , 4.6 and 1.9 per cent in laparoscopic, robot-assisted and TaTME respectively (P = 0.134). The number of incomplete specimens, circumferential resection margin involvement rate and morbidity rates did not differ. CONCLUSION: In the minimally invasive treatment of rectal cancer more primary anastomoses are created in robotic and TaTME expert centres.

The results of this study showed similar and acceptable short-term results for laparoscopic, robot-assisted and transanal total mesorectal excision performed in expert centres. In centres with robot-assisted or transanal technique, more primary anastomoses were made.

Diagnostic accuracy of urinary intestinal fatty acid binding protein in detecting colorectal anastomotic leakage.

BACKGROUND: Anastomotic leakage (AL) remains a severe complication following colorectal surgery, having a negative impact on both short- and long-term outcomes. Since timely detection could enable early intervention, there is a need for the development of novel and accurate, preferably, non-invasive markers. The aim of this study was to investigate whether urinary intestinal fatty acid binding protein (I-FABP) could serve as such a marker. METHODS: This prospective multicenter cross-sectional phase two diagnostic study was conducted at four centers in the Netherlands between March 2015 and November 2016. Urine samples of 15 patients with confirmed colorectal AL and 19 patients without colorectal AL on postoperative day 3 were included. Urinary I-FABP levels were determined using enzyme-linked immunosorbent assays and adjusted for urinary creatinine to compensate for renal dysfunction. RESULTS: Urinary I-FABP levels were significantly elevated in patients with confirmed AL compared to patients without AL on postoperative day 3 (median: 2.570 ng/ml vs 0.809 ng/ml, p = 0.006). The area under the receiver operating characteristics curve (AUROC) was 0.775, yielding a sensitivity of 80% and specificity of 74% at the optimal cutoff point (> 1.589 ng/ml). This difference remained significant after calculation of I-FABP/creatinine ratios (median: 0.564 ng/µmol vs. 0.158 ng/µmol, p = 0.040), with an AUROC of 0.709, sensitivity of 60% and specificity of 90% at the optimal cutoff point (> 0.469 ng/µmol). CONCLUSIONS: Levels of urinary I-FABP and urinary I-FABP/creatinine were significantly elevated in patients with confirmed AL following colorectal surgery, suggesting their potential as a non-invasive biomarker for colorectal anastomotic leakage.

Urinary volatile organic compound markers and colorectal anastomotic leakage.

AIM: Inflammatory markers such as serum C-reactive protein (CRP) are used as routine markers to detect anastomotic leakage following colorectal surgery. However, CRP is characterized by a relatively low predictive value, emphasizing the need for the development of novel diagnostic approaches. Volatile organic compounds (VOCs) are gaseous metabolic products deriving from all conceivable bodily excrements and reflect (alterations in) the patient's physical status. Therefore, VOCs are increasingly considered as potential non-invasive diagnostic biomarkers. The aim of this study was to assess the diagnostic accuracy of urinary VOCs for colorectal anastomotic leakage. METHODS: In this explorative multicentre study, urinary VOC profiles of 22 patients with confirmed anastomotic leakage and 27 uneventful control patients following colorectal surgery were analysed by field asymmetric ion mobility spectrometry (FAIMS). RESULTS: Urinary VOCs of patients with anastomotic leakage could be distinguished from those of control patients with high accuracy: area under the receiver operating characteristics curve 0.91 (95% CI 0.81-1.00, P < 0.001), sensitivity 86% and specificity 93%. Serum CRP was significantly increased in patients with a confirmed anastomotic leak but with lower diagnostic accuracy compared to VOC analysis (area under the receiver operating characteristics curve 0.82, 95% CI 0.68-0.95, P < 0.001). Combining VOCs and CRP did not result in a significant improvement of the diagnostic performance compared to VOCs alone. CONCLUSION: Analysis by FAIMS allowed for discrimination between urinary VOC profiles of patients with a confirmed anastomotic leak and control patients following colorectal surgery. A superior accuracy compared to CRP and apparently high specificity was observed, underlining the potential as a non-invasive biomarker for the detection of colorectal anastomotic leakage.

Multicentre study of non-surgical management of diverticulitis with abscess formation.

This multicentre retrospective cohort study included 447 patients with Hinchey Ib and II diverticular abscesses, who were treated with antibiotics, with or without percutaneous drainage. Abscesses of 3 and 5 cm in size were at higher risk of short-term treatment failure and emergency surgery respectively. Initial non-surgical treatment of Hinchey Ib and II diverticular abscesses was comparable between patients treated with antibiotics only and those who underwent percutaneous drainage in combination with antibiotics, with regard to short- and long-term outcomes. Most do not need drainage.

Oral Tobramycin Prophylaxis Prior to Colorectal Surgery Is Not Associated with Systemic Uptake.

Preoperative oral prophylaxis with nonabsorbable antibiotics has been reported to reduce the risk of surgical site infections after colorectal surgery. This prospective study was conducted to evaluate the risk of toxic side effects by measuring postoperative serum tobramycin levels in patients who received a 3-day prophylaxis with tobramycin and colistin prior to colorectal surgery. In all patients, serum tobramycin concentrations were below the detection limit (0.3 mg/liter), implying a low risk of toxicity.

Postoperative delirium in elderly after elective and acute colorectal surgery: A prospective cohort study.

OBJECTIVE: To assess the frailty and the incidence of delirium in elderly patients undergoing elective and acute colorectal surgery in correlation with morbidity and mortality. METHODS: Patients aged 65 years and older having elective and acute colorectal surgery, between April 2013 and December 2013 were included in a prospective database. Patients diagnosed with a colorectal carcinoma or diverticulitis who were operated on were included. Factors that characterize frailty of patients were noted. The incidence rates of delirium after elective and acute surgery were recorded. Delirium was diagnosed using the Delirium Observation Screening Scale (DOSS). Preoperative evaluation, surgical outcome including morbidity, hospital stay and mortality were analyzed. RESULTS: Patients ≥ 65 years were included, 83 (75%) received elective and 28 (25%) acute surgery. The overall incidence of delirium was 21%, 18% for elective and 29% for patients having urgent surgery (p = 0.24). Patients with delirium were older than the non-delirious patients (median 82 years vs. 74 years; p < 0.001). Delirious patients showed higher incidence of adverse events. Hospital stay, mortality and discharge to a nursing home were significant higher in the delirious compared to the non-delirious group (p = 0.01; 0.01; 0.02 respectively). CONCLUSION: High incidence of delirium was found in both acute and elective colorectal surgery. Delirium was associated with adverse outcomes.

Complications After Laparoscopic Cholecystectomy: A Video Evaluation Study of Whether the Critical View of Safety was Reached.

BACKGROUND: Achieving the critical view of safety (CVS) before transection of the cystic artery and duct is important to reduce biliary duct injury in laparoscopic cholecystectomy. To gain more insight into complications after laparoscopic cholecystectomy, we investigated whether the criteria for CVS were met during surgery by analyzing videos of operations performed at our institution. METHODS: All consecutive patients who underwent a completed laparoscopic cholecystectomy between 2009 and 2011 were included. The videos of the operations of patients with complications were independently reviewed and rated by two investigators with a third consulted in the event of a disagreement. The reviewers answered consecutive questions about whether the CVS criteria were met. Patients who underwent an elective laparoscopic cholecystectomy and had no complications were used as a control group for comparison. RESULTS: Of the 1108 consecutive patients who had undergone a laparoscopic cholecystectomy during the study period, 8.8 % developed complications (average age 51 years) and 1.7 % had bile duct injuries [six patients (0.6 %) had a major bile duct injury, type B, D, or E injury]. In the 65 surgical videos available for analysis, CVS was reached in 80 % of cases according to the operative notes. However, the reviewers found that CVS was reached in only 10.8 % of the cases. Only in 18.7 % of the cases the operative notes and video agreed about CVS being reached. CVS was not reached in any of the patients who had biliary injuries. In the control group, CVS was reached significantly more often in 72 %. CONCLUSIONS: In our institutional series of laparoscopic cholecystectomies with postoperative complications, CVS was reached in only a few cases. Evaluating surgical videos of laparoscopic cholecystectomy cases are important and we recommend its use to improve surgical technique and decrease the number of biliary injuries.

No change in lymph node positivity rate despite increased lymph node yield and improved survival in colon cancer.

AIM: To analyse trends over time in the number of lymph nodes evaluated and in the proportion of node positivity and to investigate the impact on survival for patients with colon cancer. PATIENTS AND METHODS: 8616 patients resected for M0 colon cancer diagnosed in the southern Netherlands between 2000 and 2011 were included in this study. Trends in nodal evaluation and node positivity were analysed. Multivariable logistic regressions were used to assess the influence of period of diagnosis on adequate nodal evaluation (P12 lymph nodes) and no depositivity after adjusting for patient and tumour characteristics. Crude 5-year relative survival was used as an estimate for disease-specific survival. RESULTS: Overall, the proportion adequate nodal evaluation increased from 13% in 2000­2002 to 59% in 2009­2011 (p < 0.0001), whereas the proportion node positivity remained similar across study periods (approximately 35%). Patients diagnosed in later periods were more likely to have received adequate nodal yield (adjusted Odds ratio (OR) 2009­2011 versus 2000­2002 9.8, 95% Confidence interval (CI) 8.3­11.6). However, the adjusted odds of having node positive disease did not differ between periods of diagnosis. Relative excess risk of dying was independently correlated with the number of lymph nodes evaluated (1­8 LNs versus P12 LNs, N0: 2.2, 95% CI 1.7­2.9; N+: 1.7, 95% CI 1.4­2.0) and period of diagnosis (2009­2011 versus 2000­2002, N+ only: 0.8, 95% CI 0.6­1.0). CONCLUSION: The reason for improved survival with increased nodal yield is different from simple understaging as the proportion of lymph node positivity remained constant.