When trainees reach competency in performing endoscopic ultrasound: a systematic review

Second-look upper endoscopy as the initial approach to subepithelial lesions: a reassuring and reliable strategy

BACKGROUND

Although endoscopic ultrasound (EUS) plays a critical role in the management of subepithelial lesions (SEL) of upper gastrointestinal tract many can be classified solely by a thorough upper gastrointestinal endoscopy (UGE) which can reduce the burden of additional studies.

AIMS

Analyze the impact of a stepwise approach starting with a second-look UGE before the decision of EUS in patients referred to our center with suspected SEL.

METHODS

Retrospective cohort study which included all adult patients referred to our center between 2015 and 2020 with suspected SEL.Second-look UGE evaluated the location, size, color, surface characteristics, movability and consistency of the SEL and bite-on-bite biopsies were performed. Decisions on SEL management and follow-up were collected.

RESULTS

A total of 193 SEL (190 patients) were included. At the index-UGE, stomach was the most frequent location (n = 115;59.6%). Most patients performed a second-look UGE (n = 180; 94.7%). A minority was oriented directly to EUS (n = 8;4.2%) or endoscopic resection (n = 2; 1.1%). In patients who underwent a second-look UGE, SEL were excluded in 25 (13.9%) and 21 (11.7%) did not need further work-up. The remaining patients were submitted to EUS (n = 88;48.9%), surveillance by UGE (n = 44; 24.4%) or endoscopic resection (n = 2; 1.1%).

CONCLUSION

Systematically performing a second-look UGE, in patients referred with suspected SEL, safely preclude the need for subsequent investigation in approximately one-fourth of the patients. As UGE is less invasive and more readily available, we suggest that a second-look UGE should be the initial approach in SEL management.

Curriculum for diagnostic endoscopic ultrasound training in Europe: European Society of Gastrointestinal Endoscopy (ESGE) Position Statement

The European Society of Gastrointestinal Endoscopy (ESGE) has recognized the need to formalize and enhance training in diagnostic endoscopic ultrasound (EUS). This manuscript represents the outcome of a formal Delphi process resulting in an official Position Statement of the ESGE and provides a framework to develop and maintain skills in diagnostic EUS. This curriculum is set out in terms of the prerequisites prior to training; the recommended steps of training to a defined syllabus; the quality of training; and how competence should be defined and evidenced before independent practice. 1:  Trainees should have achieved competence in upper gastrointestinal endoscopy before training in diagnostic EUS. 2:  The development of diagnostic EUS skills by methods that do not involve patients is advisable, but not mandatory, prior to commencing formal training in diagnostic EUS. 3:  A trainee's principal trainer should be performing adequate volumes of diagnostic EUSs to demonstrate maintenance of their own competence. 4:  Training centers for diagnostic EUS should offer expertise, as well as a high volume of procedures per year, to ensure an optimal level of quality for training. Under these conditions, training centers should be able to provide trainees with a sufficient wealth of experience in diagnostic EUS for at least 12 months. 5:  Trainees should engage in formal training and supplement this with a range of learning resources for diagnostic EUS, including EUS-guided fine-needle aspiration and biopsy (FNA/FNB). 6:  EUS training should follow a structured syllabus to guide the learning program. 7:  A minimum procedure volume should be offered to trainees during diagnostic EUS training to ensure that they have the opportunity to achieve competence in the technique. To evaluate competence in diagnostic EUS, trainees should have completed a minimum of 250 supervised EUS procedures: 80 for luminal tumors, 20 for subepithelial lesions, and 150 for pancreaticobiliary lesions. At least 75 EUS-FNA/FNBs should be performed, including mostly pancreaticobiliary lesions. 8:  Competence assessment in diagnostic EUS should take into consideration not only technical skills, but also cognitive and integrative skills. A reliable valid assessment tool should be used regularly during diagnostic EUS training to track the acquisition of competence and to support trainee feedback. 9:  A period of supervised practice should follow the start of independent activity. Supervision can be delivered either on site if other colleagues are already practicing EUS or by maintaining contacts with the training center and/or other EUS experts. 10:  Key performance measures including the annual number of procedures, frequency of obtaining a diagnostic sample during EUS-FNA/FNB, and adverse events should be recorded within an electronic documentation system and evaluated.

Development of convolutional neural network models that recognize normal anatomic structures during real-time radial-array and linear-array EUS (with videos)

BACKGROUND AND AIMS

EUS is a high-skill technique that requires numerous procedures to achieve competence. However, training facilities are limited worldwide. Convolutional neural network (CNN) models have been previously implemented for object detection. We developed 2 EUS-based CNN models for normal anatomic structure recognition during real-time linear- and radial-array EUS evaluations.

METHODS

The study was performed from February 2020 to June 2022. Consecutive patient videos of linear- and radial-array EUS videos were recorded. Expert endosonographers identified and labeled 20 normal anatomic structures within the videos for training and validation of the CNN models. Initial CNN models (CNNv1) were developed from 45 videos and the improved models (CNNv2) from an additional 102 videos. CNN model performance was compared with that of 2 expert endosonographers.

RESULTS

CNNv1 used 45,034 linear-array EUS frames and 21,063 radial-array EUS frames. CNNv2 used 148,980 linear-array EUS frames and 128,871 radial-array EUS frames. Linear-array CNNv1 and radial-array CNNv1 achieved a 75.65% and 71.36% mean average precision (mAP) with a total loss of .19 and .18, respectively. Linear-array CNNv2 obtained an 88.7% mAP with a .06 total loss, whereas radial-array CNNv2 achieved an 83.5% mAP with a .07 total loss. CNNv2 accurately detected all studied normal anatomic structures with a >98% observed agreement during clinical validation.

CONCLUSIONS

The proposed CNN models accurately recognize the normal anatomic structures in prerecorded videos and real-time EUS. Prospective trials are needed to evaluate the impact of these models on the learning curves of EUS trainees.

UK and Ireland Joint Advisory Group (JAG) consensus statements for training and certification in diagnostic endoscopic ultrasound (EUS)

BACKGROUND AND AIMS

International endoscopy societies vary in their approach for credentialing individuals in endoscopic ultrasound (EUS) to enable independent practice; however, there is no consensus in this or its implementation. In 2019, the Joint Advisory Group on GI Endoscopy (JAG) commissioned a working group to examine the evidence relating to this process for EUS. The aim of this was to develop evidence-based recommendations for EUS training and certification in the UK.

METHODS

Under the oversight of the JAG quality assurance team, a modified Delphi process was conducted which included major stakeholders from the UK and Ireland. A formal literature review was made, initial questions for study were proposed and recommendations for training and certification in EUS were formulated after a rigorous assessment using the Grading of Recommendation Assessment, Development and Evaluation tool and subjected to electronic voting to identify accepted statements. These were peer reviewed by JAG and relevant stakeholder societies before consensus on the final EUS certification pathway was achieved.

RESULTS

39 initial questions were proposed of which 33 were deemed worthy of assessment and finally formed the key recommendations. The statements covered four key domains, such as: definition of competence (13 statements), acquisition of competence (10), assessment of competence (5) and postcertification mentorship (5). Key recommendations include: (1) minimum of 250 hands-on cases before an assessment for competency can be made, (2) attendance at the JAG basic EUS course, (3) completing a minimum of one formative direct observation of procedural skills (DOPS) every 10 cases to allow the learning curve in EUS training to be adequately studied, (4) competent performance in summative DOPS assessments and (5) a period of mentorship over a 12-month period is recommended as minimum to support and mentor new service providers.

CONCLUSIONS

An evidence-based certification pathway has been commissioned by JAG to support and quality assure EUS training. This will form the basis to improve quality of training and safety standards in EUS in the UK and Ireland.

Analysis of the variation in learning curves for achieving competency in convex EUS training: a prospective cohort study using a standardized assessment tool

BACKGROUND AND AIMS

The need for mastering standard imaging techniques for convex EUS in the biliopancreatic regions has been increasing; however, large variations in the aptitude for achieving EUS competency hinder expert development. Therefore, we investigated the factors influencing the achievement of expert competency in EUS using a new assessment tool for multiple imaging items.

METHODS

Between January 2018 and February 2022, 3277 consecutive EUS procedures conducted by 5 beginners (EUS procedures <250), 7 intermediate trainees (250-749), and 2 experts (≥750) were prospectively evaluated. Immediately after each EUS procedure, the success or failure of imaging for each item was recorded using a newly developed EUS assessment tool that requires 17 items to be photographed. After correcting for missing values using multiple imputation, learning curves of EUS scores were created, and a competency was set based on expert scores. Finally, a comparative analysis between high and low performers was performed to extract factors influencing EUS scores.

RESULTS

Although 3 of 7 intermediates (43%; mean, 317 cases) achieved competency, none of the beginners achieved competency. During a comparative analysis, although no significant difference in the number of EUS procedures performed was observed between the high and low performers, the former had significantly higher scores in the written test (theoretical knowledge).

CONCLUSIONS

Our results showed that theoretical knowledge, rather than the number of EUS cases, may be a possible influencing factor for distinguishing high and low performers after treating 250 cases. (Clinical trial registration number: UMIN 000043271.).

Artificial Intelligence in Endoscopic Ultrasound for Pancreatic Cancer: Where Are We Now and What Does the Future Entail?

Pancreatic cancer is a highly lethal disease associated with significant morbidity and mortality. In the United States (US), the overall 5-year relative survival rate for pancreatic cancer during the 2012-2018 period was 11.5%. However, the cancer stage at diagnosis strongly influences relative survival in these patients. Per the National Cancer Institute (NCI) statistics for 2012-2018, the 5-year relative survival rate for patients with localized disease was 43.9%, while it was 3.1% for patients with distant metastasis. The poor survival rates are primarily due to the late development of clinical signs and symptoms. Hence, early diagnosis is critical in improving treatment outcomes. In recent years, artificial intelligence (AI) has gained immense popularity in gastroenterology. AI-assisted endoscopic ultrasound (EUS) models have been touted as a breakthrough in the early detection of pancreatic cancer. These models may also accurately differentiate pancreatic cancer from chronic pancreatitis and autoimmune pancreatitis, which mimics pancreatic cancer on radiological imaging. In this review, we detail the application of AI-assisted EUS models for pancreatic cancer detection. We also highlight the utility of AI-assisted EUS models in differentiating pancreatic cancer from radiological mimickers. Furthermore, we discuss the current limitations and future applications of AI technology in EUS for pancreatic cancers.

Increased accuracy of FNA-based cytological diagnosis of pancreatic lesions by use of an ethanol-based fixative system: A STROBE compliant study

EUS-guided fine needle aspiration cytology (FNA) is the gold standard of evaluation of solid pancreatic lesions. However, accuracy is generally low. The aim of this study was to compare the diagnostic yield of conventional cytology (CC) with liquid-based cytological analysis using an ethanol based fixative system (LBC) without onsite cytopathological assessment. We performed a retrospective evaluation in patients referred to the Department of Interdisciplinary Endoscopy at Jena University Hospital for FNA of pancreatic masses between 2008 and 2015. LBC preservation of specimen was introduced in April 2011. Gold standard was defined as a surgically obtained histology or a patient follow-up of at least 1 year for diagnosis or exclusion of malignancy. 172 patients were included into the final analysis. Mean age was 64.8 years (SD 12.4 years), 105 patients were male. 107 lesions were malignant, while 65 lesions were benign. 89 specimens were evaluated by CC, whereas 83 specimens were processed by LBC. Liquid-based cytology performed significantly better than conventional cytology in terms of sensitivity (87.8% vs 67.2% (P = .021)), specificity (100% vs 87.1% (P = .047)) negative predictive value (NPV) (85% vs 58.7% (P = .009)) and accuracy (92.8% vs 74.2% (P = .001)). We observed no learning curve after implementation of LBC Liquid based cytology is a simple and inexpensive technique that helps improving sensitivity, specificity, NPV and accuracy over conventional cytology in fine needle aspirates from patients with pancreatic lesions. Therefore, this real-world evidence shows, that EUS-FNA specimen processing should be performed using LBC to achieve best possible results.

Application of artificial intelligence in diagnosis of pancreatic malignancies by endoscopic ultrasound: a systemic review

Background

Pancreatic cancer (PC) is a highly fatal malignancy with a global overall 5-year survival of under 10%. Screening of PC is not recommended outside of clinical trials. Endoscopic ultrasonography (EUS) is a very sensitive test to identify PC but lacks specificity and is operator-dependent, especially in the presence of chronic pancreatitis (CP). Artificial Intelligence (AI) is a growing field with a wide range of applications to augment the currently available modalities. This study was undertaken to study the effectiveness of AI with EUS in the diagnosis of PC.

Methods

Studies from MEDLINE and EMBASE databases reporting the AI performance applied to EUS imaging for recognizing PC. Data were analyzed using descriptive statistics. The Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool was used to assess the quality of the included studies.

Results

A total of 11 articles reported the role of EUS in the diagnosis of PC. The overall accuracy, sensitivity, and specificity of AI in recognizing PC were 80-97.5%, 83-100%, and 50-99%, respectively, with corresponding positive predictive value (PPV) and negative predictive value (NPV) of 75-99% and 57-100%, respectively. Types of AI studied were artificial neural networks (ANNs), convolutional neural networks (CNN), and support vector machine (SVM). Seven studies using other than basic ANN reported a sensitivity and specificity of 88-96% and 83-94% to differentiate PC from CP. Two studies using SVM reported a 94-96% sensitivity, 93%-99% specificity, and 94-98% accuracy to diagnose PC from CP. The reported sensitivity and specificity of detection of malignant from benign Intraductal Papillary Mucinous Neoplasms (IPMNs) was 96% and 92%, respectively.

Conclusion

AI reported a high sensitivity with high specificity and accuracy to diagnose PC, differentiate PC from CP, and differentiate benign from malignant IPMN when used with EUS.

Endosonographers performing on-site evaluation of solid pancreatic specimens for EUS-guided biopsy: A formal training method and learning curves

Objectives:

This study aimed to examine the effects of a training program combining formal cytological curriculum and practical assessments on endosonographers and to determine how many operations were needed for training through learning curves.

Methods:

A formal cytological curriculum was implemented in November 2019 for four endosonographers. The competency of endosonographers before and after the curriculum was judged by quantitative scores. From December 2019 to October 2020, trainees independently examined the adequacy and atypia grade of pancreatic specimens acquired by EUS-guided-fine-needle biopsy based on specific atypical grading criteria. The accuracy of the adequacy and atypia assessment of each trainee was calculated, and learning curves were drawn to evaluate the improvement.

Results:

The median posttraining score improved by 87% from 49 to 91.5 out of 100. Ninety patients were enrolled in the practical assessments. The accuracy for specimen adequacy and atypia assessment of each trainee was 91.7%, 92.8%, 91.0%, and 89.3% and 80.0%, 82.1%, 81.0%, and 78.9%. The learning curves of each trainee showed a steady and significant improvement, and ninety cases were sufficient for satisfactory adequacy assessment.

Conclusions:

Basic knowledge of on-site cytopathologic evaluation can be gained through standardized and systematic training. Practical assessments showed that, at the completion of ninety cases, trained endosonographers reached a satisfactory level of recognizing specimen adequacy, but continue practice was needed for atypia assessment.

Role of Endoscopic Ultrasound in Liver Disease: Where Do We Stand?

As the burden of liver disease in the general populace steadily increases, so does the need for both advanced diagnostic and treatment options. Endoscopic ultrasound is a reliable diagnostic and therapeutic method that has an established role, foremost in pancreatobiliary pathology. This paper aims to summarize the growing role of endoscopic ultrasound in hepatology based on the search of the current literature. A number of applications of endoscopic ultrasound are reviewed, including both noninvasive methods and tissue acquisition in focal and diffuse liver disease, portal hypertension measurement, detection and management of gastric and esophageal varices, treatment of focal liver lesions and staging of pancreatobiliary malignancies, treatment of cystic and solid liver lesions, as well as liver abscess drainage. Both hepatologists and endoscopists should be aware of the evolving role of endoscopic ultrasound in liver disease. The inherent invasive nature of endoscopic examination limits its use to a targeted population identified using noninvasive methods. Endoscopic ultrasound is one the most versatile methods in gastroenterology, allowing immediate access with detection, sampling, and treatment of digestive tract pathology. Further expansion of its use in hepatology is immanent.

Curriculum for ERCP and endoscopic ultrasound training in Europe: European Society of Gastrointestinal Endoscopy (ESGE) Position Statement

The European Society of Gastrointestinal Endoscopy (ESGE) has recognized the need to formalize and enhance training in endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic ultrasound (EUS). This manuscript represents the outcome of a formal Delphi process resulting in an official Position Statement of the ESGE and provides a framework to develop and maintain skills in ERCP and EUS. This curriculum is set out in terms of the prerequisites prior to training; recommended steps of training to a defined syllabus; the quality of training; and how competence should be defined and evidenced before independent practice. 1: Trainees should be competent in gastroscopy prior to commencing training. Formal training courses and the use of simulation in training are recommended. 2: Trainees should keep a contemporaneous logbook of their procedures, including key performance indicators and the degree of independence. Structured formative assessment is encouraged to enhance feedback. There should be a summative assessment process prior to commencing independent practice to ensure there is robust evidence of competence. This evidence should include a review of a trainee's procedure volume and current performance measures. A period of mentoring is strongly recommended in the early stages of independent practice. 3: Specifically for ERCP, all trainees should be competent up to Schutz level 2 complexity (management of distal biliary strictures and stones > 10 mm), with advanced ERCP requiring a further period of training. Prior to independent practice, ESGE recommends that a trainee can evidence a procedure volume of > 300 cases, a native papilla cannulation rate of ≥ 80 % (90 % after a period of mentored independent practice), complete stones clearance of ≥ 85 %, and successful stenting of distal biliary strictures of ≥ 90 % (90 % and 95 % respectively after a mentored period of independent practice). 4: The progression of EUS training and competence attainment should start from diagnostic EUS and then proceed to basic therapeutic EUS, and finally to advanced therapeutic EUS. Before independent practice, ESGE recommends that a trainee can evidence a procedure volume of > 250 cases (75 fine-needle aspirations/biopsies [FNA/FNBs]), satisfactory visualization of key anatomical landmarks in ≥ 90 % of cases, and an FNA/FNB accuracy rate of ≥ 85 %. ESGE recognizes the often inadequate quality of the evidence and the need for further studies pertaining to training in advanced endoscopy, particularly in relation to therapeutic EUS.

Evaluation and Comparison of Performance Parameters and Impact of Telepathology and Operator Experience on Endobronchial and Endoscopic Ultrasound-Guided Fine-Needle Aspiration

OBJECTIVES

Endobronchial ultrasound- and endoscopic ultrasound-guided fine-needle aspiration (EBUS-/EUS-FNA) are minimally invasive techniques of diagnosing and staging malignancies. The procedures are difficult to master, requiring specific feedback for optimizing yield.

METHODS

Over 2 years, EBUS-/EUS-FNA cases were gathered using the institutional pathology database. Patient and specimen characteristics were collected from the pathology database and electronic medical record.

RESULTS

In 2 years, 789 unique FNA specimens were collected (356 EBUS and 433 EUS specimens). The cohort and each subgroup had excellent performance, which was enhanced by telepathology. The discrepancy rate was satisfactorily low. Hematolymphoid neoplasms are overrepresented in discrepant EBUS cases. The malignancy rates of cytology diagnostic categories were comparable to the literature.

CONCLUSIONS

Using diagnostic yield and concordance results allow for comprehensive evaluation of the entire process of EBUS-/EUS-FNAs. This study's findings can influence patient management, training methods, and interpretation of results, while also acting as a model for others to investigate their own sources of inadequacy, discrepancy, and training gaps.

Learning Curves in Health Professions Education Simulation Research: A Systematic Review

SUMMARY STATEMENT

Learning curves are used in health professions education to graphically represent paths to competence and expertise. However, research using learning curves often omit important information. The authors conducted a systematic review of the reporting quality of learning curves in simulation-based education research to identify specific areas for improvement. Reviewers extracted information on graphical, statistical, and conceptual elements. The authors identified 230 eligible articles. Most learning curve elements were reported infrequently, including use of an optimal linking function, detailed description of feedback or learning intervention, use of advanced visualization techniques such as overlaying and stacking, and depiction of competency thresholds. Reporting did not improve over time for most elements. Reporting of learning curves in health professions education research is incomplete and often underutilizes their desirable properties. Recommendations for improvement of the statistical, graphical, and conceptual reporting of learning curves, as well as applications to simulation research and education, are presented.

Training in advanced bilio-pancreatic endoscopy

As the clinical applications of endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic ultrasound (EUS) take more and more root in everyday practice and these endoscopic procedures become increasingly more complex and interventional with a higher chance for complications, the demand for expert bilio-pancreatic endoscopists continues to increase. In response to this growing need, specific postgraduate fellowships have been developed, however the standardization of training programs and the assessment of the achieved competence still remains an open debate. ERCP and EUS competency often requires training beyond the scope of a standard GI fellowship program, which lasts at least 1-2 years, and there are some differences in the way to face the issues of advanced bilio-pancreatic endoscopy training between Europe, America and the Asian regions. Today there is no role for the self-teaching of ERCP and EUS through trial and error without supervision and, in the near future, it is necessary to critically revise current training guidelines, to establish a standardized curriculum for advanced bilio-pancreatic endoscopists and to implement universally validated skill assessment tools, able to ensure constant and targeted feedback to trainees.

A deep learning-based system for bile duct annotation and station recognition in linear endoscopic ultrasound

BACKGROUND

Detailed evaluation of bile duct (BD) is main focus during endoscopic ultrasound (EUS). The aim of this study was to develop a system for EUS BD scanning augmentation.

METHODS

The scanning was divided into 4 stations. We developed a station classification model and a BD segmentation model with 10681 images and 2529 images, respectively. 1704 images and 667 images were applied to classification and segmentation internal validation. For classification and segmentation video validation, 264 and 517 videos clips were used. For man-machine contest, an independent data set contained 120 images was applied. 799 images from other two hospitals were used for external validation. A crossover study was conducted to evaluate the system effect on reducing difficulty in ultrasound images interpretation.

FINDINGS

For classification, the model achieved an accuracy of 93.3% in image set and 90.1% in video set. For segmentation, the model had a dice of 0.77 in image set, sensitivity of 89.48% and specificity of 82.3% in video set. For external validation, the model achieved 82.6% accuracy in classification. In man-machine contest, the models achieved 88.3% accuracy in classification and 0.72 dice in BD segmentation, which is comparable to that of expert. In the crossover study, trainees' accuracy improved from 60.8% to 76.3% (P < 0.01, 95% C.I. 20.9-27.2).

INTERPRETATION

We developed a deep learning-based augmentation system for EUS BD scanning augmentation.

FUNDING

Hubei Provincial Clinical Research Center for Digestive Disease Minimally Invasive Incision, Hubei Province Major Science and Technology Innovation Project, National Natural Science Foundation of China.

EUS-Directed Transgastric Endoscopic Retrograde Cholangiopancreatography (EDGE): The First Learning Curve

INTRODUCTION

Endoscopic ultrasound (EUS)-directed transgastric endoscopic retrograde cholangiopancreatography (EDGE) is a minimally invasive option for pancreaticobiliary access in patients with Roux-en-Y anatomy. The procedure involves creating a fistulous tract between the remnant stomach or jejunum and the bypassed stomach with the deployment of a lumen-apposing metal stent (LAMS), followed by the advancement of an endoscope through the LAMS to perform an ERCP or EUS. It is a technically challenging procedure, requiring skills in EUS, fluoroscopy, and LAMS deployment. The aim of this study was to determine the learning curve for EDGE.

METHODS

Consecutive patients undergoing EDGE by a single operator were included from a prospective registry over 3 years. Demographics, procedure info, postprocedure follow-up data, and adverse events were collected. Nonlinear regression and cumulative sum analyses were conducted for the learning curve. Technical success was defined as the successful creation of the fistulous tract. Clinical success was defined as successful EUS or ERCP via the LAMS.

RESULTS

Nineteen patients were included (21% male, mean age 58.7 y). Indication included symptomatic biliary stricture (n=6, 32%), choledocholithiasis (n=5, 26%), pancreatitis (n=3, 16%). Technical success was 100%. All patients had a 15 mm LAMS placed, 3 (16%) had cautery-enhanced LAMS. Clinical success was achieved in 18/19 (95%) patients. Fourteen patients had an ERCP, 1 patient had a EUS, and 3 patients had both. Adverse events included 2 cases of bleeding, 1 case of post-ERCP pancreatitis, and 1 jejunal perforation during duodenoscope insertion managed endoscopically.Median procedure time was 54.5 minutes (range: 31 to 88 min). Cumulative sum chart shows a 54-minute procedure time was achieved at the ninth procedure hence indicating efficiency. Apart from 2 outliers, the procedure duration further reduced with consequent procedures with the last 3 being under 40 minutes indicating that after 25 to 35 procedures a plateau may be reached indicating mastery (nonlinear regression P<0.0001).

CONCLUSIONS

Endoscopists experienced in EDGE are expected to achieve a reduction in procedure time over successive cases, with efficiency reached 54.5 minutes and a learning rate of 9 cases. After 25 to 35 procedures, a plateau may be reached indicating mastery.

Impact of balloon inflation on the insertion of endoscopic ultrasound: a prospective, randomized controlled trial

Background and study aims  During endoscopic ultrasound (EUS), patients may experience severe discomfort. The radial echoendoscope has a balloon around its tip. Balloon inflation prior to insertion may reduce contact injury and pharyngeal pain. The purpose of this study was to investigate the effect of balloon inflation on pharyngeal pain during insertion. Patients and methods  Patients who underwent radial EUS for pancreatobiliary disease were randomized into standard insertion or balloon-inflated insertion. The primary outcome was the proportion of moderate-to-severe pharyngeal pain. Secondary outcomes were the degree of pharyngeal pain, risk factors for moderate pharyngeal pain, procedure-related adverse events, and pharyngeal pain depending on the experience of the endoscopist. Results  A total of 481 patients were randomized into two groups: standard insertion (238) and balloon inflation (243). No statistically significant differences in proportion of moderate-to-severe pain were found (26.5 % vs. 20.2 %, P  = 0.107). Balloon inflation (HR 0.65; 95 % CI (0.42-0.98, P  = 0.041) was a protective factor against moderate pain. Balloon inflation reduced the proportion of patients with moderate-to-severe pain when performed by physicians with less than 3months of experience with EUS (44.7 % vs. 25.3 %, P  = 0.012). Conclusion  Balloon inflation did not reduce the absolute degree of post-procedural pain with EUS, but it reduced the number of patients with moderate-to-severe pain when performed by physicians with less than 3 months of experience.

Factors affecting cytological results of endoscopic ultrasound guided-fine needle aspiration during learning

Background

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is a standard procedure used to obtain tissue samples for diagnosis of solid retroperitoneal tumours. However, this procedure demands high technical expertise and requires a strong learning curve. Our aim was to identify factors associated with false-negative EUS-FNA results during the learning for endoscopists.

Methods

Our retrospective analysis was based on the EUS-FNA specimens collected by two novice endoscopists in 200 patients with retroperitoneal lesions who had confirmed image- or tissue-based diagnoses of malignancy or benign lesions.

Results

In the first 40 performances endoscopists, the false-negative diagnostic rate of EUS-FNA was higher among patients with chronic pancreatitis than in patients without chronic pancreatitis. Patients who underwent FNA through the trans-duodenal puncture route also had lower success cytological diagnosis rate than through the trans-gastric puncture route. The rate of successful cytological diagnoses with EUS-FNA improved after 40 procedures and was not influenced by chronic pancreatitis presentation or difference puncture route.

Conclusion

Regarding the learning curve, more than 40 procedures were required to achieve a stable success rate of EUS-FNA. Chronic pancreatitis and trans-duodenal puncture route are the predictive factors for a false-negative FNA cytological result during learning.

Trial registration

This was a retrospective study.

Present and Future of Endoscopic Ultrasound-Guided Tissue Acquisition in Solid Pancreatic Tumors

Endoscopic ultrasound-guided tissue acquisition (EUS-TA) is a well-established method for pathological diagnosis of solid pancreatic neoplasm. It can be performed either as EUS-guided fine-needle aspiration (EUS-FNA) or EUS-guided fine-needle biopsy (EUSFNB). The incidence of adverse events related to EUS-TA is less than 1%. The factors that affect the diagnostic accuracy and specimen adequacy include the techniques used, type and size of the needle, competency of endosonographers, presence of cytopathologists/ cytotechnologists, and rapid on-site examination. EUS-TA may contribute to precision medicine through obtaining tissue samples for next-generation sequencing. The current status, several clinical issues for diagnostic yield and adverse events, and future perspectives of EUS-FNA/FNB for diagnosing pancreatic neoplasm have been discussed in this review article.

Cystic pancreatic neuroendocrine tumors: A distinctive subgroup with indolent biological behavior? A systematic review and meta-analysis

BACKGROUND/OBJECTIVES

The clinicopathological features and biological behaviors of cystic pancreatic neuroendocrine tumors (pNETs) are unclear and controversial. Here we performed a systematic review and meta-analysis to investigate the unique characteristics of cystic pNETs, to determine whether they represent a distinct clinical entity.

METHODS

We selected comparative studies published since January 2000 that explore the differences between clinicopathological features of cystic and solid pNETs. Demographic information, pathological characteristics, and survival information were analyzed.

RESULT

The 12 selected studies comprised 355 and 1530 patients diagnosed with cystic and solid pNETs, respectively. Compared with solid pNETs, cystic pNETs were less likely to be functional (odds ratio, OR = 0.31, 95% confidence interval (CI) 0.19-0.50, p < 0.00001), more likely to affect males (OR = 1.56, 95% CI 1.22-2.00, p = 0.0005), and significantly associated with multiple endocrine neoplasia type 1 (OR = 2.71). Cystic pNETs were more likely to present with G1 and G2 rather than G3 (OR = 1.66). Cystic pNETs were associated with less frequent distant organs and lymph node metastasis, microvascular invasion, perineural invasion, and a low Ki-67 index and mitotic count. There were no significant differences between 5- and 10-year overall survival. However, the 5-year disease-free survival (DFS) and 10-year DFS rate of patients with cystic pNETs was significantly higher compared with those with solid pNETs (94.6% vs 83.5%, OR = 3.00; 92.7% vs 63.6%, OR = 5.92, respectively).

CONCLUSIONS

Cystic pNETs represent a distinct subgroup of pNETs that present with an indolent biological behavior, and patients experience better DFS. Observation and surveillance should be considered in some selected cases.

Recent advancement in EUS-guided fine needle sampling

EUS-guided tissue acquisition technique plays an essential role for evaluation of gastrointestinal tumors. Several components affect the yield of EUS-guided tissue acquisition outcomes such as sampling techniques, use of ROSE (rapid onsite evaluation), training and experience, and needle designs. In this review we discuss advancement in EUS-guided fine needle sampling.

CORTRAK Superuser Competency Assessment and Training Recommendations

BACKGROUND

Blind insertion of feeding tubes remains unsafe. Electromagnetic placement devices such as the CORTRAK Enteral Access System allow operators to interpret placement of feeding tubes in real time. However, pneumothoraces have been reported and inadequate user expertise is a concern.

OBJECTIVE

To explore factors influencing competency of CORTRAK-assisted feeding tube insertion.

METHODS

A prospective, observational pilot study was conducted. Data collection included demographics, self-confidence, clinical judgment regarding CORTRAK-assisted feeding tube insertion, and general self-efficacy. CORTRAK-assisted feeding tube insertions were performed with the Anatomical Box and CORMAN task trainers.

RESULTS

Twenty nurses who had inserted a mean of 53 CORTRAK feeding tubes participated. Participants inserted a mean of 2 CORTRAK feeding tubes weekly; each had inserted a feeding tube in the past 7 days. All superusers were competent; 1 required remediation for improper receiver unit placement. Mean (SD) scores were 35 (3.68) on a 40-point scale for self-efficacy, 4.6 (0.68) on a 5-point scale for self-reported feeding tube insertion confidence, and 4.85 (0.49) on a 5-point scale for demonstrated confidence. Participants estimated that 8 CORTRAK-assisted insertions were needed before they felt competent as super users. Confidence with the CORTRAK tracing was estimated to require 10 feeding tube insertions. Six participants continued to assess placement by auscultation, suggesting low confidence in their interpretation of the tracing.

CONCLUSIONS

At least 3 observations should be performed to assess initial competency; the number should be individualized to the operator. Interpretation of the insertion tracing is complex and requires multiple performance opportunities to gain competency and confidence for this high-risk skill.

A quarter century of EUS-FNA: Progress, milestones, and future directions

Tissue acquisition using EUS has considerably evolved since the first EUS-FNA was reported 25 years ago. Its introduction was an important breakthrough in the endoscopic field. EUS-FNA has now become a part of the diagnostic and staging algorithm for the evaluation of benign and malignant diseases of the gastrointestinal tract and of the organs in its proximity, including lung diseases. This review aims to present the history of EUS-FNA development and to provide a perspective on the recent developments in procedural techniques and needle technologies that have significantly extended the role of EUS and its clinical applications. There is a bright future ahead for EUS-FNA in the years to come as extensive research is conducted in this field and various technologies are continuously implemented into clinical practice.

Prospective evaluation of EUS-guided fine needle biopsy in pancreatic mass lesions

BACKGROUND AND STUDY AIM

Due to the scarcity of specific data on endoscopic ultrasound (EUS)-guided fine-needle biopsies (SharkCore) FNB in the evaluation of pancreatic lesions, we performed a prospective study of the diagnostic performance of EUS SharkCore FNB in patients with pancreatic lesions. The aim of this study was to evaluate the diagnostic accuracy.

PATIENTS AND METHODS

Single-center prospective study of 41 consecutive patients referred for EUS-FNB from October 2015 to April 2016 at our center. EUS-FNB was obtained in a predefined setting regarding the procedure and pathological evaluation. Data regarding demographics, lesion, technical parameters, and diagnostic accuracy were obtained.

RESULTS

The study included 41 consecutive patients (22 males (54 %); median age 68 years). The average size of the lesions was 28 mm (median: 30 mm). A diagnostic specimen was identified in 40 (98 %) cases during microscopy with an average of 2.4 passes. The route was trans-duodenal in 20 cases (49 %). The histological diagnosis of the specimens was malignant in 29 cases (71 %), benign in 8 (20 %), suspicious in 2 (5 %), atypical in 1 (2 %) and in 1 (2 %) no material for microscopic evaluation was obtained. This led to a diagnostic accuracy of 93 %, sensitivity of 91 % and a specificity of 100 %. 2 cases (5 %) of self-limiting bleeding were observed. The diagnosis at follow up was malignant in 32 (78 %) of the patients.

CONCLUSIONS

EUS-FNB of pancreatic mass lesions with the SharkCore needle produced specimens with a diagnostic accuracy of 93 %. The procedure was safe and easy to perform, and these data support the use of EUS-FNB in a routine setting.

Training in Endoscopy: Endoscopic Ultrasound

Endoscopic ultrasound (EUS) has been recently established as an indispensable modality for the diagnosis and management of pancreatobiliary and gastrointestinal (GI) disorders. EUS proficiency requires both cognitive and technical abilities, including an understanding of the appropriate indications, the performance of appropriate evaluations before and after the procedure, and the management of procedure-related complications. An increasing demand for skills to handle a growing range of interventional EUS procedures and a continual shortage of EUS training programs are two major obstacles for EUS training. Acquiring the skills necessary to comprehend and conduct EUS often requires training beyond the scope of a standard GI fellowship program. In addition to traditional formal EUS training and preceptorships, regular short-term intensive EUS training programs that provide training at various levels may help EUS practitioners improve and maintain EUS-related knowledges and skills. Theoretical knowledge can be acquired from lectures, textbooks, atlases, slides, videotapes, digital video discs, interactive compact discs, and websites. Informal EUS training is generally based on 1- or 2-day intensive seminars, including didactic lectures, skills demonstrated by expert practitioners through live video-streaming of procedures, and hands-on learning using animal or phantom models.