Rachid Mohamed

Incremental benefit of preoperative EUS for the detection of pancreatic neuroendocrine tumors: a meta-analysis

BACKGROUND Current guidelines recommend CT scan or magnetic resonance imaging as the initial imaging modalities for the work-up of suspected pancreatic neuroendocrine tumors (PNETs). OBJECTIVE To determine the incremental benefit of preoperative EUS (IBEUS) for the detection of suspected PNETs after other investigative modalities have been attempted. DESIGN This systematic review searched MEDLINE, EMBASE, bibliographies of included articles, and conference proceedings for studies reporting original data regarding the preoperative detection of PNETs. Pooled IBEUS was calculated by using random effects models. Heterogeneity was explored by using stratified meta-analysis and meta-regression. Evidence of small-study effects was assessed by using funnel plots and the Begg test. PATIENTS Patients with suspected PNETs. INTERVENTIONS EUS evaluation. MAIN OUTCOME MEASUREMENTS The pooled IBEUS for the detection of PNETs after CT scan, with or without additional investigative modalities. RESULTS Among 4505 citations identified, we included 17 cohort studies (612 patients). EUS identified PNETs in 97% of cases. Improved PNET identification with EUS was observed in all of the studies. After adjusting for small-study effects, meta-analysis showed that EUS alone could identify PNETs in approximately 1 in 4 patients (adjusted IBEUS 26%; 95% confidence interval, 17%-37%). The pooled IBEUS varied based on the study design, study size, type of CT scan used, and the number of modalities used prior to EUS. LIMITATIONS The majority of included studies were retrospective. Small-study effects were observed. CONCLUSION Preoperative EUS is associated with an increase in PNET detection after other modalities are attempted.

Evaluation of colonoscopy skills - how well are we doing?

Colonoscopy is a complex task that requires the interplay of motor and cognitive skill sets. Traditional teaching of colonoscopy involves observation in an apprenticeship model. Individual trainees vary in their rate of their skill acquisition, and this trial-and-error method often results in frustration and anxiety for both the educator and the learner. Currently, there are no guidelines to determine the competence or proficiency of an individual for colonoscopy. Furthermore, there is a paucity of information regarding formal training curricula for colonoscopy skills acquisition. The present study investigated a formal and validated educational framework for colonoscopy teaching and compared it with the traditional apprenticeship model in first-year trainees.

Learning curve for endoscopy training: Is it all about numbers?

Endoscopy training is an important component of postgraduate gastroenterology and general surgery programs. Proficiency in endoscopy requires the development of several tangible and intangible skills. Much attention has traditionally been paid to establishing a threshold, or minimum procedural volume during the training period, which is necessary for a trainee to achieve competence in endoscopy by the conclusion of his or her program. However, despite several attempts to characterize this target, it has become clear in recent years that training programs need to consider other factors rather than relying on this measure as the sole marker of trainee competency. Here, we present a review of general concepts in endoscopy skills acquisition that affect the learning curve, the evolving definition of competency as it relates to procedural volume, the role of simulation in endoscopy training, and the concept of massed versus spaced delivery of endoscopy training.

The incremental benefit of EUS for identifying unresectable disease among adults with pancreatic adenocarcinoma: A meta-analysis

Background and study aims It is unclear to what extent EUS influences the surgical management of patients with pancreatic adenocarcinoma. This systematic review sought to determine if EUS evaluation improves the identification of unresectable disease among adults with pancreatic adenocarcinoma. Patients and methods We searched MEDLINE, EMBASE, bibliographies of included articles and conference proceedings for studies reporting original data regarding surgical management and/or survival among patients with pancreatic adenocarcinoma, from inception to January 7th 2017. Our main outcome was the incremental benefit of EUS for the identification of unresectable disease (IBEUS). The pooled IBEUS were calculated using random effects models. Heterogeneity was explored using stratified meta-analysis and meta-regression. Results Among 4,903 citations identified, we included 8 cohort studies (study periods from 1992 to 2007) that examined the identification of unresectable disease (n = 795). Random effects meta-analysis suggested that EUS alone identified unresectable disease in 19% of patients (95% confidence interval [CI], 10–33%). Among those studies that considered portal or mesenteric vein invasion as potentially resectable, EUS alone was able to identify unresectable disease in 14% of patients (95% CI 8–24%) after a CT scan was performed. Limitations The majority of the included studies were retrospective. Conclusions EUS evaluation is associated with increased identification of unresectable disease among adults with pancreatic adenocarcinoma.

Contrast enhanced endoscopic ultrasound: More than just a fancy Doppler

Contrast enhanced endoscopic ultrasound (CEUS) is a new modality that takes advantage of vascular structure and blood flow to distinguish different clinical entities. Contrast agents are microbubbles that oscillate when exposed to ultrasonographic waves resulting in characteristic acoustic signals that are then converted to colour images. This permits exquisite imaging of macro- and microvasculature, providing information to help delineate malignant from non-malignant processes. The use of CEUS may significantly increase the sensitivity and specificity over conventional endoscopic ultrasound. Currently available contrast agents are safe, with infrequent adverse effects. This review summarizes the theory and technique behind CEUS and the current and future clinical applications.

Endoscopic Treatment Options in Patients With Gastrojejunal Anastomosis Stricture Following Roux-en-Y Gastric Bypass

The proportion of obese individuals continues to increase worldwide. Bariatric surgery remains the only evidence-based treatment strategy to produce marked weight loss. Roux-en-Y gastric bypass is an effective and common bariatric surgical procedure offered to obese patients. However, a small percentage of individuals can develop narrowing or stricture formation of the gastrojejunal anastomosis. Endoscopic treatment of gastrojejunostomy (GJ) is preferred compared to surgical revision, as it is less invasive. The endoscopic treatment strategy most common employed is balloon dilatation. Endoscopic balloon dilatation is successful in majority of cases with low morbidity, however multiple dilatation may be required. Other endoscopic strategies such as incisional therapy has been successful in treating other gastrointestinal anastomotic strictures, however remain to be evaluated in post-RYGB GJ strictures. Further research is needed to determine the effectiveness of incision therapy and other endoscopic treatment strategies compared to endoscopic balloon dilatation.

Diagnostic yield of small histological cores obtained with a new EUS-guided fine needle biopsy system

BackgroundAs endoscopic ultrasound-guided tissue acquisition techniques evolve, there is increasing interest in obtaining optimal histological samples to improve diagnostic accuracy. In this study, we aimed to assess the tissue acquisition success rate and test performance characteristics of a novel endoscopic ultrasound-guided fine needle biopsy (EUS-FNB) system.MethodsWe performed a retrospective review of consecutive patients undergoing EUS-guided tissue sampling of solid lesions using the SharkCore fine needle system in a tertiary referral facility. At least two passes were submitted for histology and diagnostic accuracy was evaluated. Comparison standard was based on final surgical pathology or minimum six-month clinical follow-up.ResultsSeventy-nine patients underwent 85 EUS-FNB procedures. Of the 85 histology specimens, 78 (91.7%) were adequate for diagnostic examination (includes six atypical/suspicious for adenocarcinoma). The sensitivity, specificity, and accuracy for diagnosis of malignancy with FNB were 87.1, 100, and 90.6%, respectively. Cytology was simultaneously sent in 43 cases with the same needle in addition to histology. Out of the 14 cases that were atypical/suspicious for adenocarcinoma or non-diagnostic on cytology, 11 cases (78.6%) achieved definite diagnoses on histology. The overall sensitivity, specificity, and accuracy for diagnosis of malignancy combining histology and cytology were 90.3, 100, and 92.9%, respectively. No complications were reported after the procedures.ConclusionIn this initial experience with a new EUS-guided FNB system, obtaining small cores to submit for histological analysis was safe, technically feasible, and highly accurate. Most of the histological cores obtained via FNB yielded a definite diagnosis including in cases with equivocal cytomorphology. Further study is required to confirm these findings.

Split-Dose Polyethylene Glycol Is Superior to Single Dose for Colonoscopy Preparation: Results of a Randomized Controlled Trial.

Background. The efficacy of colonoscopy in detecting abnormalities within the colon is highly dependent on the adequacy of the bowel preparation. The objective of this study was to compare the efficacy, safety, and tolerability of PEG lavage and split-dose PEG lavage with specific emphasis on the cleanliness of the right colon. Methods. The study was a prospective, randomized, two-arm, controlled trial of 237 patients. Patients between the age of 50 and 75 years were referred to an outpatient university screening clinic for colonoscopy. Patients were allocated to receive either a single 4 L PEG lavage or a split-dose PEG lavage. Results. Overall, the bowel preparation was superior in the split-dose group compared with the single-dose group (mean Ottawa score 3.50 ± 2.89 versus 5.96 ± 3.53; P < 0.05) and resulted in less overall fluid in the colon. This effect was observed across all segments of the colon assessed. Conclusions. The current study supports use of a split-dose PEG lavage over a single large volume lavage for superior bowel cleanliness, which may improve polyp detection. This trial is registered with ClinicalTrials.gov identifier NCT01610856.

Long-Term Effectiveness, Safety and Mortality Associated with the Use of TC-325 for Malignancy-Related Upper Gastrointestinal Bleeds: A Multicentre Retrospective Study

Abstract Background and Study Aims Malignant-related upper gastrointestinal bleeding (MRUGIB) is difficult to treat by conventional endoscopic methods. We sought to determine the efficacy, safety and mortality associated with the use of TC-325 for the treatment of MUGIB. Patients and Methods This is a multicentre, retrospective study at the University of Calgary and University of Ottawa performed between January 1, 2010, and July 30, 2016. TC-325 use was identified via staff polling, product order forms and endoscopic records review. Once identified, patient charts and online records were examined to identify MRUGIB cases and to assess our primary and secondary endpoints. Outcomes The primary outcome was hemostasis at seven days. Secondary outcomes include immediate hemostasis, early hemostasis, hemostasis at 14 days, 30-day mortality, adverse events related to TC-325 therapy and the need for repeat endoscopic intervention, surgery or transarterial embolization. Results Twenty-five patients were identified. The median age was 62 years (interquartile range [IQR] 52.5–76), and most were male (64%). TC-325 was the primary treatment modality in 20 patients (80%). Hemostasis was 88%, 89%, 58% and 50% at 24 hours, 72 hours, 7 days and 14 days, respectively. Five patients underwent repeat endoscopy, two patients required surgical intervention, and transarterial embolization was not required. Twelve patients died by 30 days (48%). There were no complications directly attributed to the use of TC-325. Conclusions TC-325 is effective for achieving and maintaining hemostasis in patients with malignancy-related upper gastrointestinal bleeding, and most patients do not require additional interventions. The 30-day mortality risk in this group of patients is high.

Reliability of EUS indices to detect inflammation in ulcerative colitis

BACKGROUND AND AIMS EUS is a potentially useful modality to assess severity of inflammation in ulcerative colitis (UC). We assessed the reliability of existing EUS indices and correlated them with endoscopic and histologic scores. METHODS Four blinded endosonographers assessed 58 endoscopic and EUS videos in triplicate, from patients with UC. Intrarater and interrater reliability of the hyperemia and Tsuga scores were estimated by using intra-class correlation coefficients (ICCs). Correlation with the Mayo endoscopy score, modified Baron score (MBS), Ulcerative Colitis Endoscopic Index of Severity (UCEIS), and Geboes histopathology score (GHS) were calculated by using bootstrapping methods. A RAND consensus process led to development of standardized definitions and a revised EUS-UC score. RESULTS ICCs for intrarater reliability were 0.76 (95% confidence interval [CI], 0.71-0.80) for the hyperemia score and 0.85 (95% CI, 0.79-0.89) for the Tsuga score. Corresponding values for interrater reliability were 0.34 (95% CI, 0.25-0.42) and 0.36 (95% CI, 0.24-0.46). Correlation between hyperemia and Tsuga scores to Mayo scoring system, MBS, UCEIS, and the GHS were 0.39 (95% CI, 0.15-0.61) and 0.28 (95% CI, 0.04-0.51), 0.38 (95% CI, 0.16-0.57) and 0.25 (95% CI, -0.01-0.48), 0.41 (95% CI, 0.16-0.62) and 0.27 (95% CI, 0.01-0.50), 0.37 (95% CI, -0.01-0.48) and 0.24 (95% CI, 0.13-0.57), respectively. The revised EUS-UC score included bowel wall thickening, depth of inflammation, and hyperemia. CONCLUSIONS Although substantial to almost perfect intrarater agreement existed for EUS indices in UC, interrater agreement was fair. Standardization of item definitions with development of a revised evaluative instrument has potential application as an evaluative and prognostic tool for UC. (Clinical trial registration number: NCT01852760.).