Vanash M. Patel

Metabolic surgery and cancer: protective effects of bariatric procedures.

The worldwide epidemic of obesity and the global incidence of cancer are both increasing. There is now epidemiological evidence to support a correlation between obesity, weight gain, and some cancers. Metabolic or bariatric surgery can provide sustained weight loss and reduced obesity‐related mortality. These procedures can also improve the metabolic profile to decrease cardiovascular risk and resolve diabetes in morbidly obese patients. The operations offer several physiological steps, the so‐called BRAVE effects: 1) bile flow alteration, 2) reduction of gastric size, 3) anatomical gut rearrangement and altered flow of nutrients, 4) vagal manipulation and 5) enteric gut hormone modulation. Metabolic operations are also associated with a significant reduction of cancer incidence and mortality. The cancer‐protective role of metabolic surgery is strongest for female obesity‐related tumors; however, the underlying mechanisms may involve both weight‐dependent and weight‐independent effects. These include the improvement of insulin resistance with attenuation of the metabolic syndrome as well as decreased oxidative stress and inflammation in addition to the beneficial modulation of sex steroids, gut hormones, cellular energetics, immune system, and adipokines. Elucidating the precise metabolic mechanisms of cancer prevention by metabolic surgery can increase our understanding of how obesity, diabetes, and metabolic syndrome are associated with cancer. It may also offer novel treatment strategies in the management of tumor generation and growth. Cancer 2011.

Body Mass Index Category as a Risk Factor for Colorectal Adenomas: A Systematic Review and Meta-Analysis

OBJECTIVES:The association between increasing body weight and colorectal adenoma prevalence has been suggested to follow a similar pattern to excess weight and colorectal cancer, although the magnitude of this relationship has not been validated. The objective of this study was to quantify the association and dose–response relationship between body mass index (BMI) and colorectal adenoma prevalence in clinical trials.METHODS:We systematically reviewed 23 studies (168,201 participants), which compared the prevalence of colorectal adenomas according to World Health Organization BMI categories. We assessed the effects of each BMI category on colorectal adenomas where odds ratio (OR) was used as a surrogate for effect size, and applied multivariate meta-analysis as a method of sensitivity analysis to evaluate the robustness of our findings and to analyze adenoma prevalence by multiple BMI categories simultaneously to assess for a dose–response relationship. Heterogeneity and publication bias were assessed.RESULTS:Subjects with a BMI of ≥25 had a significantly higher prevalence of colorectal adenomas (OR=1.24 (95% confidence interval (CI): 1.16–1.33), P<0.01) when compared with those with BMI<25. Multivariate meta-analysis also confirmed a positive association between higher BMI categories and the prevalence of colorectal adenoma (BMI: 25–30 vs. BMI<25; OR=1.21 (95% CI: 1.07–1.38), P<0.01; BMI≥30 vs. BMI<25; OR=1.32 (95% CI: 1.18–1.48), P<0.01) and revealed a dose–response relationship.CONCLUSIONS:The positive association between obesity and colorectal adenoma prevalence demonstrates an underlying dose–response relationship according to BMI. Colorectal centers may benefit from the timely screening of obese patients for colorectal adenomas in addition to clarifying the biological role of adiposity on colorectal tumor initiation and progression.

Current status of robotic assisted pelvic surgery and future developments.

AIMS The aim of this review is to assess the role of robotics in pelvic surgery in terms of outcomes. We have also highlighted the issues related to training and future development of robotic systems. MATERIALS AND METHODS We searched MEDLINE, EMBASE and the Cochrane Databases from 1980 to 2009 for systematic reviews of randomised controlled trials, prospective observational studies, retrospective studies and case reports assessing robotic surgery. RESULTS During the last decade, there has been a tremendous rise in the use of robotic surgical systems for all forms of precision operations including pelvic surgery. The short-term results of robotic pelvic surgery in the fields of urology, colorectal surgery and gynaecology have been shown to be comparable to the laparoscopic and open surgery. Robotic surgery offers an opportunity where many of these obstacles encountered during open and laparoscopic surgery can be overcome. CONCLUSIONS Robotic surgery is a continually advancing technology, which has opened new horizons for performing pelvic surgery with precision and accuracy. Although its use is rapidly expanding in all surgical disciplines, particularly in pelvic surgery, further comparative studies are needed to provide robust guidance about the most appropriate application of this technology within the surgical armamentarium.

How has healthcare research performance been assessed? A systematic review

Objectives Healthcare research performance is increasingly assessed through research indicators. We performed a systematic review to identify the indicators that have been used to measure healthcare research performance. We evaluated their feasibility, validity, reliability and acceptability; and finally assessed the utility of these indicators in terms of measuring performance in individuals, specialties, institutions and countries. Design A systematic review was performed by searching EMBASE, PsycINFO, Ovid MEDLINE and Cochrane Library databases between 1950 and September 2010. Setting Studies of healthcare research were appraised. Healthcare was defined as the prevention, treatment and management of illness and the preservation of mental and physical wellbeing through the services offered by the medical and allied health professions. Participants All original studies that evaluated research performance indicators in healthcare were included. Main outcome measures Healthcare research indicators, data sources, study characteristics, results and limitations for each study were studied. Results The most common research performance indicators identified in 50 studies were: number of publications (n = 38), number of citations (n = 27), Impact Factor (n = 15), research funding (n = 10), degree of co-authorship (n = 9), and h index (n = 5). There was limited investigation of feasibility, validity, reliability and acceptability, although the utility of these indicators was adequately described. Conclusion Currently, there is only limited evidence to assess the value of healthcare research performance indicators. Further studies are required to define the application of these indicators through a balanced approach for quality and innovation. The ultimate aim of utilizing healthcare research indicators is to create a culture of measuring research performance to support the translation of research into greater societal and economic impact.

What does leadership in surgery entail

Background:  Leadership is not formally taught at any level in surgical training; there are no mandatory leadership courses or qualifications for trainees or specialists, and leadership performance is rarely evaluated within surgical appraisal or assessment programmes.

Is the structure of anatomy curriculum adequate for safe medical practice

INTRODUCTION Anatomy has been considered a core subject within the medical education curriculum. In the current setting of ever-changing diagnostic and treatment modalities, the opinion of both students and trainers is crucial for the design of an anatomy curriculum which fulfils the criteria required for safe medical practice. METHODS Medical students, trainees and specialist trainee doctors and specialists from the London (England) area were surveyed to investigate the how curriculum changes have affected the relevance of anatomical knowledge to clinical practice and to identify recommendations for optimum teaching methods. The survey employed 5-point Likert scales and multiple-choice questions. Where the effect of training level was statistically significant (p < 0.05), post-hoc analysis was carried out using Mann-Whitney U tests. Significance levels were modified according to the Bonferroni method. RESULTS Two hundred and twenty-eight individuals completed the survey giving a response rate of 53%. Medical students, trainees and specialists all agreed (mean Likert score 4.51, 4.79, 4.69 respectively) that knowledge of anatomy is important for medical practice. Most of the trainees (88.4%) and specialists (81.3%) used dissection to learn anatomy, but only 61.4% of medical students used this approach. Dissection was the most commonly recommended approach for learning anatomy across all the groups (41.7%-69.3%). CONCLUSIONS Knowledge of anatomy is perceived to be important for safe clinical practice. Anatomy should be taught with other relevant system or clinical modules. Newer tools for anatomy teaching need further validation before incorporation into the curriculum.

Evidence-based surgery: Barriers, solutions, and the role of evidence synthesis

BackgroundSurgery is a rapidly evolving field, making the rigorous testing of emerging innovations vital. However, most surgical research fails to employ randomized controlled trials (RCTs) and has particularly been based on low-quality study designs. Subsequently, the analysis of data through meta-analysis and evidence synthesis is particularly difficult.MethodsThrough a systematic review of the literature, this article explores the barriers to achieving a strong evidence base in surgery and offers potential solutions to overcome the barriers.ResultsMany barriers exist to evidence-based surgical research. They include enabling factors, such as funding, time, infrastructure, patient preference, ethical issues, and additionally barriers associated with specific attributes related to researchers, methodologies, or interventions. Novel evidence synthesis techniques in surgery are discussed, including graphics synthesis, treatment networks, and network meta-analyses that help overcome many of the limitations associated with existing techniques. They offer the opportunity to assess gaps and quantitatively present inconsistencies within the existing evidence of RCTs.ConclusionsPoorly or inadequately performed RCTs and meta-analyses can give rise to incorrect results and thus fail to inform clinical practice or revise policy. The above barriers can be overcome by providing academic leadership and good organizational support to ensure that adequate personnel, resources, and funding are allocated to the researcher. Training in research methodology and data interpretation can ensure that trials are conducted correctly and evidence is adequately synthesized and disseminated. The ultimate goal of overcoming the barriers to evidence-based surgery includes the improved quality of patient care in addition to enhanced patient outcomes.

Transhiatal esophagectomy in a high volume institution.

BackgroundThe optimal operative approach for carcinoma at the lower esophagus and esophagogastric junction remains controversial. The aim of this study was to assess a single unit experience of transhiatal esophagectomy in an era when the use of systemic oncological therapies has increased dramatically.Study DesignBetween January 2000 and November 2006, 215 consecutive patients (182 males, 33 females, median age = 65 years) underwent transhiatal esophagectomy; invasive malignancy was detected preoperatively in 188 patients. 90 patients (42%) received neoadjuvant chemotherapy. Prospective data was obtained for these patients and cross-referenced with cancer registry survival data.ResultsThere were 2 in-hospital deaths (0.9%). Major complications included: respiratory complications in 65 patients (30%), cardiovascular complications in 31 patients (14%) and clinically apparent anastomotic leak in 12 patients (6%). Median length of hospital stay was 14 days. The radicality of resection was inversely related to T stage: an R0 resection was achieved in 98–100% of T0/1 tumors and only 14% of T4 tumors. With a median follow up of 26 months, one and five year survival rates were estimated at 81% and 48% respectively.ConclusionTranshiatal esophagectomy is an effective operative approach for tumors of the infracarinal esophagus and the esophagogastric junction. It is associated with low mortality and morbidity and a five survival rate of nearly 50% when combined with neoadjuvant chemotherapy.

Specialist anatomy: Is the structure of teaching adequate?

BACKGROUND A knowledge and understanding of specialist anatomy, which includes radiological, laparoscopic, endoscopic and endovascular anatomy is essential for interpretation of imaging and development of procedural skills. METHODS AND MATERIALS Medical students, specialist trainees and specialists from the London (England, UK) area were surveyed to investigate individual experiences and recommendations for: (1) timing of the introduction of specialist anatomy teaching, and (2) pedagogical methods used. Opinions relating to radiological, laparoscopic, endoscopic and endovascular anatomy were collected. Non-parametric tests were used to investigate differences in recommendations between specialist trainees and specialists. RESULTS Two hundred and twenty-eight (53%) individuals responded to the survey. Imaging was most commonly used to learn radiological anatomy (94.5%). Procedural observation was most commonly used to learn laparoscopic (89.0%), endoscopic (87.3%) and endovascular anatomy (66.2%). Imaging was the most recommended method to learn radiological anatomy (92.1%). Procedural observation was the most recommended method for learning laparoscopic (80.0%), endoscopic (81.2%) and endovascular anatomy (42.5%). Specialist trainees and specialists recommended introduction of specialist anatomy during undergraduate training. CONCLUSION Although the methods for specialist anatomy learning are in practice, there is no consensus on timing and structure within the anatomy curriculum. Recommendations from trainees and specialists should be considered so that the existing curriculum can be refined to maximise learning outcomes.

Outcome of Patients on Renal Replacement Therapy after Colorectal Surgery

PurposePatients on renal replacement therapy are reported to have a high complication rate after abdominal surgery, the result of uremia and immunosuppression. A review of this group of patients undergoing colorectal surgery was undertaken.MethodsSeventy-three separate colorectal operations were performed for 44 patients. Thirty-eight patients were on dialysis and 35 had a renal transplant. Data (coexisting disease, preoperative blood results, operative details, complications, and colorectal POSSUM score) were completed for each surgical event.ResultsForty-two elective and 31 emergency procedures were performed. Infective complications were common (overall 60 percent). There were two anastomotic leaks in the elective group, but five leaks from seven emergency anastomoses. Stomas were frequently raised. Ninety percent of patients who survived and had a defunctioning stoma underwent a successful reversal. The overall major complication rate after elective and emergency surgery was 19 and 81 percent, respectively, and mortality was 5 and 26 percent, respectively.ConclusionsRenal patients have a high rate of complications after colorectal surgery, and emergency surgery has a significant risk of anastomotic leak. Primary anastomosis should be avoided in all patients undergoing emergency intestinal resections. Subsequent surgery to restore intestinal continuity is possible in 90 percent of patients with far fewer complications.