George B. Hanna

Consensus guidelines for validation of virtual reality surgical simulators

Abstract.The Work Group for Evaluation and Implementation of Simulators and Skills Training Programmes is a newly formed sub-group of the European Association of Endoscopic Surgeons (EAES). This work group undertook a review of validation evidence for surgical simulators and the resulting consensus is presented in this article. Using clinical guidelines criteria, the evidence for validation for six different simulators was rated and subsequently translated to a level of recommendation for each system. The simulators could be divided into two basic types; systems for laparoscopic general surgery and flexible gastrointestinal endoscopy. Selection of simulators for inclusion in this consensus was based on their availability and relatively widespread usage as of July 2004. Whilst level 2 recommendations were achieved for a few systems, it was clear that there was an overall lack of published validation studies with rigorous experimental methodology. Since the consensus meeting, there have been a number of new articles, system upgrades and new devices available. The work group intends to update these consensus guidelines on a regular basis, with the resulting article available on the EAES website (http://www.eaes-eur.org ).

Observational tools for assessment of procedural skills: a systematic review

BACKGROUND Assessment by direct observation of procedural skills is an important source of constructive feedback. The aim of this study was to identify observational tools for technical skill assessment, to assess characteristics of these tools, and to assess their usefulness for assessment. METHODS Included studies reported tools for observational assessment of technical skills. A total of 106 articles were included. RESULTS Three main categories included global assessment scales evaluating generic skills (n = 29), task-specific methods assessing procedure-specific skills (n = 30), and combinations of tools evaluating both generic and task-specific skills (n = 47). In most studies, content validity was not evaluated using an accepted scientific method. All tools were assessed for inter-rater reliability and construct validity. Data on feasibility, acceptability, and educational impact were sparse. CONCLUSIONS There is evidence of validity and reliability for observational assessment tools at the trainee level. In most studies a comprehensive analysis of the tools was not achieved. Evaluation of technical skill using current observational assessment tools is not reliable and valid at the specialist level. Future research needs to focus on further systematic tool development and analysis, especially at the specialist level.

Short-term outcomes following open versus minimally invasive esophagectomy for cancer in England: a population-based national study.

Objective: To compare short-term outcomes of open and minimally invasive esophagectomy (MIE) for cancer. Background Data: Numerous studies have demonstrated the safety and possible advantages of MIE in selected cohorts of patients. The increasing use of MIE is not coupled with conclusive evidence of its benefits over “open” esophagectomy, especially in the absence of randomized trials. Methods: Hospital Episode Statistics data were analyzed from April 2005 to March 2010. This is a routinely collected database of all English National Health Service Trusts. Office of Population Censuses and Surveys Classification of Surgical Operations and Procedures, 4th revision (OPCS-4), procedure codes were used to identify index resections and International Statistical Classification of Diseases, 10th Revision (ICD-10), diagnostic codes were used to ascertain comorbidity status and complications. Thirty-day in-hospital mortality, medical complications, and surgical reinterventions were analyzed. Unadjusted and risk-adjusted regression analyses were undertaken. Results: Seven thousand five hundred and two esophagectomies were undertaken; of these, 1155 (15.4%) were MIE. In 2009–2010, 24.7% of resections were MIE. There was no difference in 30-day mortality (4.3% vs 4.0%; P = 0.605) and overall medical morbidity (38.0% vs 39.2%; P = 0.457) rates between open and MIE groups, respectively. A higher reintervention rate was associated with the MIE group than with the open group (21% vs 17.6%, P = 0.006; odds ratio, 1.17; 95% confidence interval, 1.00–1.38; P = 0.040). Conclusions: Minimally invasive esophagectomy is increasingly performed in the United Kingdom. Although the study confirmed the safety of MIE in a population-based national data, there are no significant benefits demonstrated in mortality and overall morbidity. Minimally invasive esophagectomy is associated with higher reintervention rate. Further evidence is needed to establish the long-term survival of MIE.

Transthoracic versus transhiatal esophagectomy for the treatment of esophagogastric cancer: a meta-analysis.

Objective:To study the differences in short and long-term outcomes of transthoracic and transhiatal esophagectomy for cancer. Background:Studies have compared transthoracic with transhiatal esophagectomy with varying results. Previous systematic reviews (1999, 2001) do not include the latest randomized controlled trials. Methods:Systematic review of English-language studies comparing transthoracic with transhiatal esophagectomy up to January 31, 2010. Meta-analysis was used to summate the study outcomes. Methodological and surgical quality of included studies was assessed. Results:Fifty-two studies, comprising 5905 patients (3389 transthoracic and 2516 transhiatal) were included in the analysis. No study met all minimum surgical quality standards. Transthoracic operations took longer and were associated with a significantly longer length of stay. There was no difference in blood loss. The transthoracic group had significantly more respiratory complications, wound infections, and early postoperative mortality, whereas anastomotic leak, anastomotic stricture, and recurrent laryngeal nerve palsy rate was significantly higher in the transhiatal group. Lymph node retrieval was reported in 4 studies and was significantly greater in the transthoracic group by on average 8 lymph nodes. Analysis of 5-year survival showed no significant difference between the groups and was subject to significant heterogeneity. Conclusions:This meta-analysis of studies comparing transthoracic with transhiatal esophagectomy for cancer demonstrates no difference in 5-year survival, however lymphadenectomy and reported surgical quality was suboptimal in both groups and the transthoracic group had significantly more advanced cancer. The finding of equivalent survival should therefore be viewed with caution.

Learning Curve and Case Selection in Laparoscopic Colorectal Surgery: Systematic Review and International Multicenter Analysis of 4852 Cases

BACKGROUND: The learning curve for laparoscopic colorectal surgery has not been conclusively analyzed. No reliable framework for case selection during training is available. OBJECTIVE: The aim of this study was to analyze thelength of the learning curve of laparoscopic colorectal surgeons and to recommend a case selectionframework at the early stage of independent practice. DATA SOURCES: Medline (1988–2010, October week 4) and Embase (1988–2010) were used for the literature review, databases were retrieved from the authors, and expert opinion was surveyed. STUDY SELECTION: Studies describing the learning curve of laparoscopic or laparoscopically assisted colorectal surgery were selected. INTERVENTION: No interventions were performed. MAIN OUTCOME MEASURES: Learning curves were analyzed by using risk-adjusted, bootstrapped cumulative sum curves. Conversions and complications were independent variables in a multilevel random-effects regression model. Recommendations are based on analysis of ORs and a structured expert opinion gauging process. RESULTS: Twenty-three studies were identified, showing great disparity on the length of the learning curve. Seven studies, representing 4852 cases (19 surgeons), were analyzed. Risk-adjusted cumulative sum charts demonstrated the length of the learning curves to be 152 cases for conversions, 143 for complications, 96 for operating time, 87 for blood loss, and 103 for length of stay. Body mass index and pelvic dissection (rectum), especially in male patients, independently increased the risk of complication and conversion. The expert survey revealed that increasing T stage and complicated inflammatory disease are likely to increase the complexity of the case. Based on this evidence, a framework for case selection in training was proposed. LIMITATIONS: The generalizability of the study results maybe reduced because of inconsistent data quality and individual variations in the length of the learning curve CONCLUSIONS: This multicenter database suggests a length of the learning curve of 88 to 152 cases. The use of the suggested framework may prevent high conversion and complication rates during the learning curve.

Tracking the genomic evolution of esophageal adenocarcinoma through neoadjuvant chemotherapy

UNLABELLED Esophageal adenocarcinomas are associated with a dismal prognosis. Deciphering the evolutionary history of this disease may shed light on therapeutically tractable targets and reveal dynamic mutational processes during the disease course and following neoadjuvant chemotherapy (NAC). We exome sequenced 40 tumor regions from 8 patients with operable esophageal adenocarcinomas, before and after platinum-containing NAC. This revealed the evolutionary genomic landscape of esophageal adenocarcinomas with the presence of heterogeneous driver mutations, parallel evolution, early genome-doubling events, and an association between high intratumor heterogeneity and poor response to NAC. Multiregion sequencing demonstrated a significant reduction in thymine to guanine mutations within a CpTpT context when comparing early and late mutational processes and the presence of a platinum signature with enrichment of cytosine to adenine mutations within a CpC context following NAC. Esophageal adenocarcinomas are characterized by early chromosomal instability leading to amplifications containing targetable oncogenes persisting through chemotherapy, providing a rationale for future therapeutic approaches. SIGNIFICANCE This work illustrates dynamic mutational processes occurring during esophageal adenocarcinoma evolution and following selective pressures of platinum exposure, emphasizing the iatrogenic impact of therapy on cancer evolution. Identification of amplifications encoding targetable oncogenes maintained through NAC suggests the presence of stable vulnerabilities, unimpeded by cytotoxics, suitable for therapeutic intervention.

Laparoscopic assisted distal gastrectomy for early gastric cancer: Is it an alternative to the open approach?

OBJECTIVE This study aims to compare short term outcomes and oncological value of laparoscopy assisted (LADG) and open distal gastrectomy (ODG) in the treatment of early gastric cancer. METHODS Meta-analysis of 12 studies, including three randomized controlled trials, published between 2000 and 2007, comparing laparoscopy assisted and open distal gastrectomy in 951 patients with early gastric cancer, was done. Outcomes of interest were operative data, lymph node clearance, postoperative recovery complications. RESULTS Overall morbidity rate was significantly less with LADG (10.5% versus 20.1%, P=0.003, OR 0.52, CI 0.34-0.8). A mean of 4.61 less number of lymph nodes dissected than ODG (CI -5.96, -3.26 P<0.001) when all studies are included. There was no difference between the two groups in number of lymph nodes dissected when less than D2 lymphadenectomy was done (2.44 nodes less in LADG group, CI -5.52, 0.63; P=0.12). LADG patients had less operative blood loss (mean of 151ml, P<0.001), less time to walking, oral intake and flatus. LADG patients had less length of hospital stay (5.7days, P<0.001), postoperative fever and pain. ODG group showed significantly less operative time. There was no significant difference between the two groups in the incidence of anastomotic complications and wound infection. CONCLUSION LADG is a safe technical alternative to ODG for early gastric cancer with a lower overall complication rate and enhanced postoperative recovery. Endorsing LADG as a better alternative to ODG requires data on long term survival, quality of life and cost effectiveness.

Systematic Review on Mentoring and Simulation in Laparoscopic Colorectal Surgery

Objective: To identify and evaluate the influence of mentoring and simulated training in laparoscopic colorectal surgery (LCS) and define the key components for learning advanced technical skills. Background: Laparoscopic colorectal surgery is a complex procedure, often being self-taught by senior surgeons. Educational issues such as inadequate training facilities or a shortfall of training fellowships may result in a slow uptake of LCS. The effectiveness of mentored and simulated training, however, remains unclear. Methods: We conducted a systematic search, using Ovid databases. Four study categories were identified: mentored versus nonmentored cases, training case selection, simulation, and assessment. We performed a meta-analysis and a mixed model regression on the difference of the main outcome measures (conversion rates, morbidity, and mortality) for mentored trainees and expert surgeons. We also compared conversion rates of mentored and nonmentored. Meta-analysis of risk factors for conversion was performed using published and unpublished data sets requested from various investigators. For studies on simulation, we compared scores of surveys on the perception of different training courses. Results: Thirty-seven studies were included. Pooled weighted outcomes of mentored cases (n = 751) showed a lower conversion rate (13.3% vs 20.5%, P = 0.0332) compared with nonmentored cases (n = 695). Compared to expert case series (n = 5313), there was no difference in conversion (P = 0.2835), anastomotic leak (P = 0.8342), or mortality (P = 0.5680). A meta-analysis of training case selection data (n = 4444) revealed male sex (P < 0.0001), previous abdominal surgery (P = 0.0200), a BMI greater than 30 (P = 0.0050), an ASA of less than 2 (P < 0.0001), colorectal cancer (P < 0.0001) and intra-abdominal fistula (P < 0.0001), but not older than 64 years (P = 0.4800), to significantly increase conversion risk. Participants on cadaveric courses were highly satisfied with the teaching value yet trainees on an animal course gave less positive feedback. Structured assessment for LCS has been partially implemented. Conclusion: This review and meta-analysis supports evidence that trainees can obtain similar clinical results like expert surgeons in laparoscopic colorectal surgery if supervised by an experienced trainer. Cadaveric models currently provide the best value for training in a simulated environment. There remains a need for further research into technical skills assessment and the educational value of simulated training.

COLOR III: a multicentre randomised clinical trial comparing transanal TME versus laparoscopic TME for mid and low rectal cancer

IntroductionTotal mesorectal excision (TME) is an essential component of surgical management of rectal cancer. Both open and laparoscopic TME have been proven to be oncologically safe. However, it remains a challenge to achieve complete TME with clear circumferential resections margin (CRM) with the conventional transabdominal approach, particularly in mid and low rectal tumours. Transanal TME (TaTME) was developed to improve oncological and functional outcomes of patients with mid and low rectal cancer.MethodsAn international, multicentre, superiority, randomised trial was designed to compare TaTME and conventional laparoscopic TME as the surgical treatment of mid and low rectal carcinomas. The primary endpoint is involved CRM. Secondary endpoints include completeness of mesorectum, residual mesorectum, morbidity and mortality, local recurrence, disease-free and overall survival, percentage of sphincter-saving procedures, functional outcome and quality of life. A Quality Assurance Protocol including centralised MRI review, histopathology re-evaluation, standardisation of surgical techniques, and monitoring and assessment of surgical quality will be conducted.DiscussionThe difference in involvement of CRM between the two treatment strategies is thought to be in favour of the TaTME. TaTME is therefore expected to be superior to laparoscopic TME in terms of oncological outcomes in case of mid and low rectal carcinomas.

Transanal Total Mesorectal Excision: International Registry Results of the First 720 Cases

Objective: This study aims to report short-term clinical and oncological outcomes from the international transanal Total Mesorectal Excision (taTME) registry for benign and malignant rectal pathology. Background: TaTME is the latest minimally invasive transanal technique pioneered to facilitate difficult pelvic dissections. Outcomes have been published from small cohorts, but larger series can further assess the safety and efficacy of taTME in the wider surgical population. Methods: Data were analyzed from 66 registered units in 23 countries. The primary endpoint was “good-quality TME surgery.” Secondary endpoints were short-term adverse events. Univariate and multivariate regression analyses were used to identify independent predictors of poor specimen outcome. Results: A total of 720 consecutively registered cases were analyzed comprising 634 patients with rectal cancer and 86 with benign pathology. Approximately, 67% were males with mean BMI 26.5 kg/m2. Abdominal or perineal conversion was 6.3% and 2.8%, respectively. Intact TME specimens were achieved in 85%, with minor defects in 11% and major defects in 4%. R1 resection rate was 2.7%. Postoperative mortality and morbidity were 0.5% and 32.6% respectively. Risk factors for poor specimen outcome (suboptimal TME specimen, perforation, and/or R1 resection) on multivariate analysis were positive CRM on staging MRI, low rectal tumor <2 cm from anorectal junction, and laparoscopic transabdominal posterior dissection to <4 cm from anal verge. Conclusions: TaTME appears to be an oncologically safe and effective technique for distal mesorectal dissection with acceptable short-term patient outcomes and good specimen quality. Ongoing structured training and the upcoming randomized controlled trials are needed to assess the technique further.