Complete mesocolic excision versus standard resection for colon cancer: a systematic review and meta-analysis of perioperative safety and an evaluation of the use of a robotic approach.

PURPOSE: Complete mesocolic excision (CME) has been associated with improved oncological outcomes in treatment of colon cancer. However, widespread adoption is limited partly because of the technical complexity and perceived risks of the approach. The aim of out study was to evaluate the safety of CME compared to standard resection and to compare robotic versus laparoscopic approaches. METHODS: Two parallel searches were undertaken in MEDLINE, Embase and Web of Science databases 12 December 2021. The first was to evaluate IDEAL stage 3 evidence to compare complication rates as a surrogate marker of perioperative safety between CME and standard resection. The second independent search compared lymph node yield and survival outcomes between minimally invasive approaches. RESULTS: There were four randomized control trials (n = 1422) comparing CME to standard resection, and three studies comparing laparoscopic (n = 164) to robotic (n = 161) approaches. Compared to standard resection, CME was associated with a reduction in Clavien-Dindo grade 3 or higher complication rates (3.56% vs. 7.24%, p = 0.002), reduced blood loss (113.1 ml vs. 137.6 ml, p < 0.0001) and greater mean lymph node harvest (25.6 vs. 20.9 nodes, p = 0.001). Between the robotic and laparoscopic groups, there were no significant differences in complication rates, blood loss, lymph node yield, 5-year disease-free survival (OR 1.05, p = 0.87) and overall survival (OR 0.83, p = 0.54). CONCLUSIONS: Our study demonstrated improved safety with CME. There was no difference in safety or survival outcomes between robotic and laparoscopic CME. The advantage of a robotic approach may lie in the reduced learning curve and an increased penetration of minimally invasive approach to CME. Further studies are required to explore this. PROSPERO ID: CRD42021287065.

Implementation of a clinical pathway for the surgical treatment of colorectal cancer during the COVID-19 pandemic.

AIM: This report summarizes the early experience of implementing elective colorectal cancer surgery during the COVID-19 pandemic. METHODS: A pathway to minimize the risk of including COVID-19-positive patients for elective surgery was established. Prioritization and additional safety measures were introduced into clinical practice. Minimal invasive surgery was used where appropriate. RESULTS: Thirty-eight patients were prioritized, and 23 patients underwent surgery (eight colon, 14 rectal and one anal cancer). The minimal invasive surgery rate was 78%. There were no major postoperative complications or patients diagnosed with COVID-19. Histopathological outcomes were similar to normal practice. CONCLUSION: A safe pathway to offer standard high-quality surgery to colorectal cancer patients during the COVID-19 pandemic is feasible.

Expert consensus on a train-the-trainer curriculum for robotic colorectal surgery.

AIM: Robotic techniques are being increasingly used in colorectal surgery. There is, however, a lack of training opportunities and structured training programmes. Robotic surgery has specific problems and challenges for trainers and trainees. Ergonomics, specific skills and user-machine interfaces are different from those in traditional laparoscopic surgery. The aim of this study was to establish expert consensus on the requirements for a robotic train-the-trainer curriculum amongst robotic surgeons and trainers. METHOD: This is a modified Delphi-type study involving 14 experts in robotic surgery teaching. A reiterating 19-item questionnaire was sent out to the same group and agreement levels analysed. A consensus of 0.8 or higher was considered to be high-level agreement. RESULTS: Response rates were 93-100% and most items reached high levels of agreement within three rounds. Specific requirements for a robotic faculty development curriculum included maximizing dual-console teaching, theatre team training, nontechnical skills training, patient safety, user-machine interface training and telementoring. CONCLUSION: A clear need for the development of a train-the-trainer curriculum has been identified. Further research is needed to assess feasibility, effectiveness and clinical impact of a robotic train-the-trainer curriculum.

European consensus on the standardization of robotic total mesorectal excision for rectal cancer.

AIM: Surgery for rectal cancer is challenging for both technical and anatomical reasons. The European Academy of Robotic Colorectal Surgery (EARCS) provides a competency-based training programme through a standardized approach. However, there is no consensus on technical standards for robotic surgery when used during surgery for rectal cancer. The aim of this consensus study was to establish operative standards for anterior resection incorporating total mesorectal excision (TME) using robotic techniques, based on recommendations of expert European colorectal surgeons. METHOD: A Delphi questionnaire with a 72-item statement was sent through an electronic survey tool to 24 EARCS faculty members from 10 different countries who were selected based on expertise in robotic colorectal surgery. The task was divided into theatre setup, colonic mobilization and rectal dissection, and each task area was further divided into several subtasks. The levels of agreement (A* > 95% agreement, A > 90%, B > 80% and C > 70%) were considered adequate while agreement of < 70% was considered inadequate. Once consensus was reached, a draft document was compiled and sent out for final approval. RESULTS: The average length of experience of robotic colorectal surgery for participants in this study was 6 years. Initial agreement was 87%; in nine items, it was < 70%. After suggested modifications, the average level of agreement for all items reached 94% in the second round (range 0.75-1). CONCLUSION: This is the first European consensus on the standardization of robotic TME. It provides a baseline for technical standards and structured training in robotic rectal surgery.

IntAct: intra-operative fluorescence angiography to prevent anastomotic leak in rectal cancer surgery: a randomized controlled trial.

AIM: Anastomotic leak (AL) is a major complication of rectal cancer surgery. Despite advances in surgical practice, the rates of AL have remained static, at around 10-15%. The aetiology of AL is multifactorial, but one of the most crucial risk factors, which is mostly under the control of the surgeon, is blood supply to the anastomosis. The MRC/NIHR IntAct study will determine whether assessment of anastomotic perfusion using a fluorescent dye (indocyanine green) and near-infrared laparoscopy can minimize the rate of AL leak compared with conventional white-light laparoscopy. Two mechanistic sub-studies will explore the role of the rectal microbiome in AL and the predictive value of CT angiography/perfusion studies. METHOD: IntAct is a prospective, unblinded, parallel-group, multicentre, European, randomized controlled trial comparing surgery with intra-operative fluorescence angiography (IFA) against standard care (surgery with no IFA). The primary end-point is rate of clinical AL at 90 days following surgery. Secondary end-points include all AL (clinical and radiological), change in planned anastomosis, complications and re-interventions, use of stoma, cost-effectiveness of the intervention and quality of life. Patients should have a diagnosis of adenocarcinoma of the rectum suitable for potentially curative surgery by anterior resection. Over 3 years, 880 patients from 25 European centres will be recruited and followed up for 90 days. DISCUSSION: IntAct will rigorously evaluate the use of IFA in rectal cancer surgery and explore the role of the microbiome in AL and the predictive value of preoperative CT angiography/perfusion scanning.

Open compared with laparoscopic complete mesocolic excision with central lymphadenectomy for colon cancer: a systematic review and meta-analysis.

AIM: Several studies report improved survival in colon cancer with use of extended lymphadenectomy techniques (ELTs), such as D3 lymphadenectomy or complete mesocolic excision. The noninferiority of laparoscopic versus open techniques has already been established in D2 resections. The aim of this study was to compare the safety and efficacy of open and laparoscopic approaches for ELTs in colon cancer. METHOD: Major databases, including PubMed, Scopus and the Cochrane library, were searched using defined inclusion and exclusion criteria, and relevant data were extracted. The Cochrane and Newcastle-Ottawa tools were used for critical appraisal and quality assessment. Meta-analysis with various subgroup analyses were undertaken, and clinical and statistical heterogeneity, along with publication bias, were also assessed. RESULTS: One randomized and seven case-control trials were included. All studies were found to be of low methodological quality with some external validity issues. There was no difference in short-term mortality [OR = 2.16 (95% CI: 0.73-6.41); P = 0.16], anastomotic leakage, ileus or deep-sited infection/abscess. There was a trend for longer operative time [weighted mean difference (WMD) = -30.88 (95% CI: -62.38 to 0.61); P = 0.05] and shorter length of hospital stay [WMD = 2.29 (95% CI: -0.39 to 4.98); P = 0.09] with the laparoscopic approach. Laparoscopic right hemicolectomy had a lower wound-infection rate [OR = 2.87 (95% CI: 1.38-5.98); P = 0.005] compared with the relevant open group. No statistically significant difference was found in overall survival [hazard ratio (HR) = 0.85 (95% CI: 0.69-1.06); P = 0.15], disease-free survival, local recurrence and distant metastases. CONCLUSION: Based on the current evidence, the laparoscopic technique appears to be at least as safe as the open technique when used in performing ELTs for colonic cancer, with similar morbidity and oncological outcomes.

Application of objective clinical human reliability analysis (OCHRA) in assessment of technical performance in laparoscopic rectal cancer surgery.

BACKGROUND: Laparoscopic rectal resection is technically challenging, with outcomes dependent upon technical performance. No robust objective assessment tool exists for laparoscopic rectal resection surgery. This study aimed to investigate the application of the objective clinical human reliability analysis (OCHRA) technique for assessing technical performance of laparoscopic rectal surgery and explore the validity and reliability of this technique. METHODS: Laparoscopic rectal cancer resection operations were described in the format of a hierarchical task analysis. Potential technical errors were defined. The OCHRA technique was used to identify technical errors enacted in videos of twenty consecutive laparoscopic rectal cancer resection operations from a single site. The procedural task, spatial location, and circumstances of all identified errors were logged. Clinical validity was assessed through correlation with clinical outcomes; reliability was assessed by test-retest. RESULTS: A total of 335 execution errors identified, with a median 15 per operation. More errors were observed during pelvic tasks compared with abdominal tasks (p < 0.001). Within the pelvis, more errors were observed during dissection on the right side than the left (p = 0.03). Test-retest confirmed reliability (r = 0.97, p < 0.001). A significant correlation was observed between error frequency and mesorectal specimen quality (r s = 0.52, p = 0.02) and with blood loss (r s = 0.609, p = 0.004). CONCLUSIONS: OCHRA offers a valid and reliable method for evaluating technical performance of laparoscopic rectal surgery.

Examining the elemental contribution towards the biodegradation of Mg-Zn-Ca ternary metallic glasses.

The Mg-Zn-Ca metallic glass system has been the focus of recent studies as a prospective material for biodegradable implants. To date, the influence each alloying element has on the degradation behaviour of this class of alloy is still not well understood. This study employs electrochemical polarisation and in situ impedance spectroscopy coupled with H2 gas collection in simulated body fluid at 37 °C to elucidate the mechanisms by which a series of custom produced Mg-Zn-Ca metallic glasses degrade compared with high purity Mg. The results show that Mg-Zn-Ca metallic glasses provide significantly more noble corrosion potentials and suppressed hydrogen gas evolution relative to high purity Mg. Furthermore, the role each element has in degradation was investigated systematically by varying the concentration of each alloying element. Testing revealed that the complex nature of dissolution in metallic glasses requires testing beyond solely polarisation and hydrogen gas collection to elucidate degradation behaviour in vitro. Practical limits to which the composition may be adjusted in this ternary alloy system, so as to maintain minimal degradation, have been achieved.

Clinical validity of consultant technical skills assessment in the English National Training Programme for Laparoscopic Colorectal Surgery.

BACKGROUND: The English National Training Programme for Laparoscopic Colorectal Surgery introduced a validated objective competency assessment tool to accredit surgeons before independent practice. The aim of this study was to determine whether this technical skills assessment predicted clinical outcomes. METHODS: Established consultants, training in laparoscopic colorectal surgery, were asked to submit two operative videos for evaluation by two blinded assessors using the competency assessment tool. A mark of 2·7 or above was considered a pass. Clinical and oncological outcomes were compared above and below this mark, including regression analysis. RESULTS: Eighty-five consultant surgeons submitted 171 videos. Of these, 44 (25·7 per cent) were in the fail group (score less than 2·7). This low scoring group had more postoperative morbidity (25 versus 8·7 per cent; P = 0·005), including surgical complications (18 versus 6·3 per cent; P = 0·020) and fewer lymph nodes harvested (median 13 versus 18; P = 0·004). A score of less than 2·7 was an independent predictor of surgical complication, lymph node yield and distal resection margin clearance. Consultants with higher scores had performed similar numbers of laparoscopic colorectal operations (median 37 versus 40; P = 0·373) but more structured training operations (18 versus 9; P < 0·001). CONCLUSION: An objective technical skills assessment provided a discriminatory tool with which to accredit laparoscopic colorectal surgeons.

A new technique of extreme lateral positioning for laparoscopic splenic flexure mobilization.

AIM: This aim of this study was to describe a novel positioning technique that assists in the expeditious mobilization of the splenic flexure without the need for redraping or compromise of port placement. METHOD: A prospective case series was studied to evaluate the technique and its ability to facilitate splenic flexure mobilization. RESULTS: The technique was used in 12 patients. There were no adverse intra- or postoperative events. The median time (interquartile range) for laparoscopic splenic flexure mobilisation was 10 (9-11.25). CONCLUSION: This novel positioning technique is safe and feasible. We include a detailed video that describes and demonstrates the requisites for its safe conduct. We also include intra-operative footage demonstrating the benefits of the patient's position.

Major postoperative complications following elective resection for colorectal cancer decrease long-term survival but not the time to recurrence.

AIM: The aim of the study was to determine the effect of major complications after colorectal cancer surgery on survival and time to recurrence. METHOD: Patients having a curative colorectal cancer resection and a follow-up of at least 3 years were identified from a prospective database. Major complications were defined as Clavien-Dindo Grades 3b or 4 and their impact on time to recurrence and mortality was analysed by univariate and multivariable analysis. Postoperative death within 30 days or during the initial hospitalization (Clavien-Dindo Grade 5) was a priori excluded. RESULTS: From 2003 to 2012, 868 colorectal cancer resections resulting in 63 (7%) major postoperative complications including deaths (Clavien-Dindo ≥ 3b) were identified. After exclusion of Grade 5 complications (postoperative or in-hospital deaths), 844 resections with 39 (5%) major complications remained for analysis. Median follow-up time was 5.7 years. Using the Kaplan-Meier method, the estimated crude 5-year overall survival probability was 78% (95% CI 75-81) in the group without and 65% (95% CI 51-83) in the group with major complications (P = 0.009, log-rank test). Major complications were a significant negative predictor for overall survival (hazard ratio 2.42, 95% CI 1.41-4.14) when adjusted for sex, age, American Society of Anesthesiologists grade, tumour site (colon vs rectum), R stage and tumour stage. However, in both univariate and multivariable analysis, major complications were not a significant predictor for time to recurrence (hazard ratio 1.29, 95% CI 0.56-2.99). CONCLUSION: Non-lethal major postoperative complications seem to have a negative long-term impact on survival but not on time to recurrence.

Colorectal cancer is reliably excluded in the frail and elderly population by minimal preparation CT.

BACKGROUND: This study aimed to retrospectively assess the accuracy of minimal preparation computed tomography (MPCT) in the detection of colorectal cancer (CRC) within the frail and elderly population and to evaluate the relevance of extra-colonic findings (ECF). METHODS: Radiology reports, clinical notes and follow-up reports from 207 patients who underwent MPCT to investigate for CRC between 2005 and 2009 were analysed. Patients were scanned following the administration of oral contrast for 48 h, without bowel preparation or colonic insufflation. MPCT results were measured against patient outcomes, with a minimum of 2 years of follow-up. RESULTS: Twelve cases of clinically relevant CRC were confirmed (5.8 %). MPCT correctly identified 11 of these lesions (sensitivity 91.6 %). Thirty-one patients had a possible CRC identified by MPCT, which was not confirmed by further examination (specificity 84.1 %). This results in a positive predictive value of 26.2 % and a negative predictive value of 99.4 %. Five of the patients with colon cancer underwent curative surgery. Sixty-eight clinically relevant ECF were confirmed, including 14 previously undiagnosed extra-colonic malignancies. ECF were considered to account for the presenting complaint in 15.0 % (31/207) of all patients. CONCLUSIONS: Minimal preparation computed tomography is an effective and reliable investigation for the exclusion of clinically relevant CRC in this population. It provides clinicians with a valuable and pragmatic alternative to colonoscopy and CT colonography when invasive examination or cathartic bowel preparation will be poorly tolerated and small polyps are of limited significance. MPCT has an advantage over purely luminal imaging in the detection of extra-colonic pathology and appears to have an equally important role in the detection of CRC.

A novel method for determining the difficulty of colonoscopic polypectomy.

INTRODUCTION: Endoscopists are now expected to perform polypectomy routinely. Colonic polypectomy varies in difficulty, depending on polyp morphology, size, location and access. The measurement of the degree of difficulty of polypectomy, based on polyp characteristics, has not previously been described. OBJECTIVE: To define the level of difficulty of polypectomy. METHODS: Consensus by nine endoscopists regarding parameters that determine the complexity of a polyp was achieved through the Delphi method. The endoscopists then assigned a polyp complexity level to each possible combination of parameters. A scoring system to measure the difficulty level of a polyp was developed and validated by two different expert endoscopists. RESULTS: Through two Delphi rounds, four factors for determining the complexity of a polypectomy were identified: size (S), morphology (M), site (S) and access (A). A scoring system was established, based on size (1-9 points), morphology (1-3 points), site (1-2 points) and access (1-3 points). Four polyp levels (with increasing level of complexity) were identified based on the range of scores obtained: level I (4-5), level II (6-9), level III (10-12) and level IV (>12). There was a high degree of interrater reliability for the polyp scores (interclass correlation coefficient of 0.93) and levels (κ=0.888). CONCLUSIONS: The scoring system is feasible and reliable. Defining polyp complexity levels may be useful for planning training, competency assessment and certification in colonoscopic polypectomy. This may allow for more efficient service delivery and referral pathways.

'Trainee' evaluation of the English National Training Programme for laparoscopic colorectal surgery.

AIM: The aim of this study was to review trainees' opinions of the training they had received through the National Training Programme (NTP). METHOD: An online questionnaire was distributed to NTP trainees who had completed five or more training episodes within the programme. Demographic data were collected. Opinion was given using a five-point Likert scale (1 = strongly disagree, 2 = disagree, 3 = undecided, 4 = agree, 5 = strongly agree). Percentages, mean values and SD were presented. ANOVA and Mann-Whitney U-tests were used to examine the impact of different factors on ratings and the difference between ratings, respectively. RESULTS: Fifty-four registered trainees fulfilled the inclusion criteria, and 37 (69% response rate) completed the questionnaire. Teaching sessions were organized using an inreach (11%), in-house (11%), outreach (27%) or combination (51%) system of training. Trainees felt that their trainers seldom cancelled sessions (93%), that it was easy to organize (92%) and consent (100%) the patient, and that their hospital was supportive of training (97%). Trainees stated that overall their trainers were excellent at training (Likert scale = 4.71 ± 0.46) and that they received regular feedback (87%). The only variable to have a significant impact on the level of NTP approval was whether the trainee was able to choose his or her trainer (supportive of NTP, chose trainer P = 0.050; critical of NTP, chose trainer P = 0.020). CONCLUSION: The large majority of trainees was highly satisfied with the training received in this innovative programme, irrespective of region or training structure used, thus demonstrating acceptability of the programme in its current form.

Randomized controlled trial investigating the effect of music on the virtual reality laparoscopic learning performance of novice surgeons.

BACKGROUND: Findings have shown that music affects cognitive performance, but little is known about its influence on surgical performance. The hypothesis of this randomized controlled trial was that arousing (activating) music has a beneficial effect on the surgical performance of novice surgeons in the setting of a laparoscopic virtual reality task. METHODS: For this study, 45 junior surgeons with no previous laparoscopic experience were randomly assigned to three equal groups. Group 1 listened to activating music; group 2 listened to deactivating music; and group 3 had no music (control) while each participant solved a surgical task five times on a virtual laparoscopic simulator. The assessed global task score, the total task time, the instrument travel distances, and the surgeons' heart rate were assessed. RESULTS: All surgical performance parameters improved significantly with experience (task repetition). The global score showed a trend for a between-groups difference, suggesting that the group listening to activating music had the worst performance. This observation was supported by a significant between-groups difference for the first trial but not subsequent trials (activating music, 35 points; deactivating music, 66 points; no music, 91 points; p = 0.002). The global score (p = 0.056) and total task time (p = 0.065) showed a trend toward improvement when participants considered the music pleasant rather than unpleasant. CONCLUSIONS: Music in the operating theater may have a distracting effect on novice surgeons performing new tasks. Surgical trainers should consider categorically switching off music during teaching procedures.

Effect of bisacodyl on postoperative bowel motility in elective colorectal surgery: a prospective, randomized trial.

BACKGROUND: Postoperative ileus is a common condition after abdominal surgery. Many prokinetic drugs have been evaluated including osmotic laxatives. The data on colon-stimulating laxatives are scarce. This prospective, randomized, double-blind trial investigates the effect of the colon-stimulating laxative bisacodyl on postoperative ileus in elective colorectal resections. MATERIALS AND METHODS: Between November 2004 and February 2007, 200 consecutive patients were randomly assigned to receive either bisacodyl or placebo. Primary endpoint was time to gastrointestinal recovery (mean time to first flatus passed, first defecation, and first solid food tolerated; GI-3). Secondary endpoints were incidence and duration of nasogastric tube reinsertion, incidence of vomiting, length of hospital stay, and visual analogue scores for pain, cramps, and nausea. RESULTS: One hundred sixty-nine patients were analyzed, and 31 patients discontinued the study. Groups were comparable in baseline demographics. Time to GI-3 was significantly shorter in the bisacodyl group (3.0 versus 3.7 days, P = 0.007). Of the single parameters defining GI-3, there was a 1-day difference in time to defecation in favor to the bisacodyl group (3.0 versus 4.0 days, P = 0.001), whereas no significant difference in time to first flatus or tolerance of solid food was seen. No significant difference in the secondary endpoints was seen. Morbidity and mortality did not differ between groups. CONCLUSION: Bisacodyl accelerated gastrointestinal recovery and might be considered as part of multimodal recovery programs after colorectal surgery.

Time dependent effects of dexamethasone on serum insulin level and insulin receptors in rat liver and erythrocytes.

The effects of glucocorticoid excess on regulation of insulin receptors were investigated in dexamethasone-treated rats. Glucocorticoid excess was produced by administration of dexamethasone (0.5 mg/100 g b.w.) 30 min, 4, 12, 18, 24, 42 or 70 h before experiments. This treatment caused time-dependent changes of glucose and insulin concentration in blood, as well as in amounts of specific insulin binding and insulin receptors of liver cells and erythrocytes. The time intervals in which dexamethasone produced the increase in insulin concentration were accompanied with decrease in insulin binding to receptors in membranes of liver cells, while significant changes in insulin binding to receptors of erythrocytes were not observed under the same experimental conditions. The effect is maximal 18 and 42 h after dexamethasone treatment that increase insulin blood level by about 85% and 60%, respectively. Receptor analysis revealed that changes in specific binding of insulin could be due to significant changes in amount of binding sites on cell surface rather than to mild alteration in receptor affinity. These findings suggest that besides the changes in insulin level, the alterations in insulin receptor number and affinity may play a major role in the states of altered insulin sensitivity which accompany glucocorticoid excess.