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Dive into the research topics where Violette C. Simon is active.

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Featured researches published by Violette C. Simon.


Clinical Gastroenterology and Hepatology | 2017

Increasing Number of Passes Beyond 4 Does Not Increase Sensitivity of Detection of Pancreatic Malignancy by Endoscopic Ultrasound–Guided Fine-Needle Aspiration

Mehdi Mohamadnejad; Dayna S. Early; Brian T. Collins; Carrie Marshall; Sharon B. Sams; Roy D. Yen; Mona Rizeq; Maria M. Romanas; Samia Nawaz; Ozlem Ulusarac; Thomas Hollander; Robert H. Wilson; Violette C. Simon; Vladimir M. Kushnir; Stuart K. Amateau; Brian C. Brauer; Srinivas Gaddam; Riad R. Azar; Srinadh Komanduri; Raj J. Shah; Ananya Das; Steven A. Edmundowicz; V. Raman Muthusamy; Amit Rastogi; Sachin Wani

BACKGROUND & AIMS It is not clear exactly how many passes are required to determine whether pancreatic masses are malignant using endoscopic ultrasound–guided fine‐needle aspiration (EUS‐FNA). We aimed to define the per‐pass diagnostic yield of EUS‐FNA for establishing the malignancy of a pancreatic mass, and identify factors associated with detection of malignancies. METHODS In a prospective study, 239 patients with solid pancreatic masses were randomly assigned to groups that underwent EUS‐FNA, with the number of passes determined by an on‐site cytopathology evaluation or set at 7 passes, at 3 tertiary referral centers. A final diagnosis of pancreatic malignancy was made based on findings from cytology, surgery, or a follow‐up evaluation at least 1 year after EUS‐FNA. The cumulative sensitivity of detection of malignancy by EUS‐FNA was calculated after each pass; in the primary analysis, lesions categorized as malignant or suspicious were considered as positive findings. RESULTS Pancreatic malignancies were found in 202 patients (84.5% of the study population). EUS‐FNA detected malignancies with 96% sensitivity (95% confidence interval [CI], 92%–98%); 4 passes of EUS‐FNA detected malignancies with 92% sensitivity (95% CI, 87%–95%). Tumor size greater than 2 cm was the only variable associated with positive results from cytology analysis (odds ratio, 7.8; 95% CI, 1.9–31.6). In masses larger than 2 cm, 4 passes of EUS‐FNA detected malignancies with 93% sensitivity (95% CI, 89%–96%) and in masses ≤2 cm, 6 passes was associated with 82% sensitivity (95% CI, 61%–93%). Sensitivity of detection did not increase with increasing number of passes. CONCLUSIONS In a prospective study, we found 4 passes of EUS‐FNA to be sufficient to detect malignant pancreatic masses; increasing the number of passes did not increase the sensitivity of detection. Tumor size greater than 2 cm was associated with malignancy, and a greater number of passes may be required to evaluate masses 2 cm or less. ClinicalTrials.gov number, NCT01386931.


Clinical Gastroenterology and Hepatology | 2017

A Prospective Multicenter Study Evaluating Learning Curves and Competence in Endoscopic Ultrasound and Endoscopic Retrograde Cholangiopancreatography Among Advanced Endoscopy Trainees: The Rapid Assessment of Trainee Endoscopy Skills Study

Sachin Wani; Matthew Hall; Samuel Han; Meer Akbar Ali; Brian C. Brauer; Linda Carlin; Amitabh Chak; Dan Collins; Gregory A. Cote; David L. Diehl; Christopher J. DiMaio; Andrew M. Dries; Ihab I. El-Hajj; Swan Ellert; Kimberley Fairley; Ashley L. Faulx; Larissa L. Fujii-Lau; Srinivas Gaddam; Seng Ian Gan; Jonathan P. Gaspar; Chitiki Gautamy; Stuart R. Gordon; Cynthia L. Harris; Sarah Hyder; Ross Jones; Stephen Kim; Srinadh Komanduri; Ryan Law; Linda Lee; Rawad Mounzer

BACKGROUND & AIMS: On the basis of the Next Accreditation System, trainee assessment should occur on a continuous basis with individualized feedback. We aimed to validate endoscopic ultrasound (EUS) and endoscopic retrograde cholangiopancreatography (ERCP) learning curves among advanced endoscopy trainees (AETs) by using a large national sample of training programs and to develop a centralized database that allows assessment of performance in relation to peers. METHODS: ASGE recognized training programs were invited to participate, and AETs were graded on ERCP and EUS exams by using a validated competency assessment tool that assesses technical and cognitive competence in a continuous fashion. Grading for each skill was done by using a 4‐point scoring system, and a comprehensive data collection and reporting system was built to create learning curves by using cumulative sum analysis. Individual results and benchmarking to peers were shared with AETs and trainers quarterly. RESULTS: Of the 62 programs invited, 20 programs and 22 AETs participated in this study. At the end of training, median number of EUS and ERCP performed/AET was 300 (range, 155–650) and 350 (125–500), respectively. Overall, 3786 exams were graded (EUS, 1137; ERCP‐biliary, 2280; ERCP‐pancreatic, 369). Learning curves for individual end points and overall technical/cognitive aspects in EUS and ERCP demonstrated substantial variability and were successfully shared with all programs. The majority of trainees achieved overall technical (EUS, 82%; ERCP, 60%) and cognitive (EUS, 76%; ERCP, 100%) competence at conclusion of training. CONCLUSIONS: These results demonstrate the feasibility of establishing a centralized database to report individualized learning curves and confirm the substantial variability in time to achieve competence among AETs in EUS and ERCP. ClinicalTrials.gov: NCT02509416.


Endoscopy International Open | 2017

Recurrence of intestinal metaplasia and early neoplasia after endoscopic eradication therapy for Barrett’s esophagus: A systematic review and meta-analysis

Larissa L. Fujii-Lau; Birtukan Cinnor; Nicholas J. Shaheen; Srinivas Gaddam; Srinadh Komanduri; V. Raman Muthusamy; Ananya Das; Robert H. Wilson; Violette C. Simon; Vladimir M. Kushnir; Steven A. Edmundowicz; Dayna S. Early; Sachin Wani

Background  Conflicting data exist with regard to recurrence rates of intestinal metaplasia (IM) and dysplasia after achieving complete eradication of intestinal metaplasia (CE-IM) in Barrett’s esophagus (BE) patients. Aim  (i) To determine the incidence of recurrent IM and dysplasia achieving CE-IM and (ii) to compare recurrence rates between treatment modalities [radiofrequency ablation (RFA) with or without endoscopic mucosal resection (EMR) vs stepwise complete EMR (SRER)]. Methods  A systematic search was performed for studies reporting on outcomes and estimates of recurrence rates after achieving CE-IM. Pooled incidence [per 100-patient-years (PY)] and risk ratios with 95 %CI were obtained. Heterogeneity was measured using the I 2 statistic. Subgroup analyses, decided a priori, were performed to explore heterogeneity in results. Results  A total of 39 studies were identified (25-RFA, 13-SRER, and 2 combined). The pooled incidence of any recurrence was 7.5 (95 %CI 6.1 – 9.0)/100 PY with a pooled incidence of IM recurrence rate of 4.8 (95 %CI 3.8 – 5.9)/100 PY, and dysplasia recurrence rate of 2.0 (95 %CI 1.5 – 2.5)/100 PY. Compared to the SRER group, the RFA group had significantly higher overall [8.6 (6.7 – 10.5)/100 PY vs. 5.1 (3.1 – 7)/100 PY, P  = 0.01] and IM recurrence rates [5.8 (4.3 – 7.3)/100 PY vs. 3.1 (1.7 – 4)/100 PY, P  < 0.01] with no difference in recurrence rates of dysplasia. Significant heterogeneity between studies was identified. The majority of recurrences were amenable to repeat endoscopic eradication therapy (EET). Conclusion  The results of this study demonstrate that the incidence rates of overall, IM, and dysplasia recurrence rates post-EET are not inconsiderable and reinforce the importance of close surveillance after achieving CE-IM.


Clinical Gastroenterology and Hepatology | 2017

Suboptimal Agreement Among Cytopathologists in Diagnosis of Malignancy Based on Endoscopic Ultrasound Needle Aspirates of Solid Pancreatic Lesions: A Validation Study

Carrie Marshall; Rawad Mounzer; Matthew Hall; Violette C. Simon; Barbara A. Centeno; Katie L. Dennis; Jasreman Dhillon; Fang Fan; Laila Khazai; Jason B. Klapman; Srinadh Komanduri; Xiaoqi Lin; David Lu; Sanjana Mehrotra; V. Raman Muthusamy; Ritu Nayar; Ajit Paintal; Jianyu Rao; Sharon B. Sams; Janak N. Shah; Rabindra R. Watson; Amit Rastogi; Sachin Wani

Background & Aims: Despite the widespread use of endoscopic ultrasound‐guided fine‐needle aspiration (EUS‐FNA) to sample pancreatic lesions and the standardization of pancreaticobiliary cytopathologic nomenclature, there are few data on inter‐observer agreement among cytopathologists evaluating pancreatic cytologic specimens obtained by EUS‐FNA. We developed a scoring system to assess agreement among cytopathologists in overall diagnosis and quantitative and qualitative parameters, and evaluated factors associated with agreement. Methods: We performed a prospective study to validate results from our pilot study that demonstrated moderate to substantial inter‐observer agreement among cytopathologists for the final cytologic diagnosis. In the first phase, 3 cytopathologists refined criteria for assessment of quantity and quality measures. During phase 2, EUS‐FNA specimens of solid pancreatic lesions from 46 patients were evaluated by 11 cytopathologists at 5 tertiary care centers using a standardized scoring tool. Individual quantitative and qualitative measures were scored and an overall cytologic diagnosis was determined. Clinical and EUS parameters were assessed as predictors of unanimous agreement. Inter‐observer agreement (IOA) was calculated using multi‐rater kappa (&kgr;) statistics and a logistic regression model was created to identify factors associated with unanimous agreement. Results: The IOA for final diagnoses, based on cytologic analysis, was moderate (&kgr; = 0.56; 95% CI, 0.43–0.70). Kappa values did not increase when categories of suspicious for malignancy, malignant, and neoplasm were combined. IOA was slight to moderate for individual quantitative (&kgr; = 0.007; 95% CI, –0.03 to –0.04) and qualitative parameters (&kgr; = 0.5; 95% CI, 0.47–0.53). Jaundice was the only factor associated with agreement among all cytopathologists on multivariate analysis (odds ratio for unanimous agreement, 5.3; 95% CI, 1.1–26.89). Conclusions: There is a suboptimal level of agreement among cytopathologists in the diagnosis of malignancy based on analysis of EUS‐FNA specimens obtained from solid pancreatic masses. Strategies are needed to refine the cytologic criteria for diagnosis of malignancy and enhance tissue acquisition techniques to improve diagnostic reproducibility among cytopathologists.


Gastroenterology | 2017

Suboptimal Interobserver Agreement (IOA) Amongt Cytopathologists (CYPS) for Pancreatic Endoscopic Ultrasound Fine Needle Aspiration (EUS-FNA) Cytology Specimens: a Multicenter Validation Study

Sachin Wani; Rawad Mounzer; Matthew Hall; Violette C. Simon; Barbara A. Centeno; Katie L. Dennis; Jasreman Dhillon; Fang Fan; Laila Khazai; Jason B. Klapman; Sri Komanduri; Xiaoqi Lin; David Lu; Sanjana Mehrotra; V. Raman Muthusamy; Ritu Nayar; Ajit Paintal; Jianyu Rao; Sharon B. Sams; Janak N. Shah; Timothy M. Tynan; Rabindra R. Watson; Amit Rastogi; Carrie Marshall


Gastrointestinal Endoscopy | 2018

929 MOST ADVANCED ENDOSCOPY TRAINEES (AETS) MEET QUALITY INDICATOR (QI) THRESHOLDS IN THE FIRST YEAR OF INDEPENDENT PRACTICE: THE RAPID ASSESSMENT OF TRAINEE ENDOSCOPY SKILLS (RATES2) STUDY

Sachin Wani; Dayna S. Early; Samuel Han; Eva Aagaard; Violette C. Simon; Linda Carlin; Swan Ellert; Michael J. Bartel; Erik Bowman; Hemant Chatrath; Abhishek Choudhary; Bradley Confer; Gregory A. Cote; Koushik K. Das; Christopher J. DiMaio; Abdul Hamid El Chafic; Steven A. Edmundowicz; Jason Ferriera; Bhargava Gannavarapu; Hazem T. Hammad; Sujai Jalaj; Sri Komanduri; Gabriel Lang; V. Raman Muthusamy; Kavous Pakseresht; Amit Rastogi; Brian P. Riff; Shreyas Saligram; Raj J. Shah; Rishi Sharma


Gastrointestinal Endoscopy | 2018

525 PRACTICE PATTERNS AND BELIEFS IN THE USE OF ADVANCED IMAGING MODALITIES (AIMS) IN SURVEILLANCE OF BARRETT’S ESOPHAGUS (BE): A SURVEY OF INTERNATIONAL EXPERTS

Jorge D. Machicado; Samuel Han; Violette C. Simon; Bashar J. Qumseya; Shahnaz Sultan; Sri Komanduri; Amit Rastogi; V. Raman Muthusamy; Vladimir M. Kushnir; Rehan Haidry; Rajvinder Singh; Rena Yadlapati; Krish Ragunath; Nicholas J. Shaheen; Sachin Wani


Gastrointestinal Endoscopy | 2018

762 SETTING MINIMUM STANDARDS FOR TRAINING IN EUS AND ERCP: RESULTS FROM A PROSPECTIVE MULTICENTER STUDY EVALUATING LEARNING CURVES AND COMPETENCE AMONG ADVANCED ENDOSCOPY TRAINEES (AETS)

Sachin Wani; Samuel Han; Violette C. Simon; Matthew Hall; Dayna S. Early; Eva Aagaard; Linda Carlin; Swan Ellert; Wasif M. Abidi; Todd H. Baron; Brian C. Brauer; Hemant Chatrath; Gregory A. Cote; Koushik K. Das; Christopher J. DiMaio; Steven A. Edmundowicz; Ihab I. El Hajj; Hazem T. Hammad; Sujai Jalaj; Michael L. Kochman; Sri Komanduri; Linda S. Lee; V. Raman Muthusamy; Andrew S. Nett; Mojtaba Olyaee; Kavous Pakseresht; Pranith Perera; Patrick R. Pfau; Cyrus R. Piraka; Amit Rastogi


Gastroenterology | 2018

Factors Associated With Poor Adherence to Quality Indicators in Barrett’s Esophagus

Samuel Han; Rena Yadlapati; Kelli DeLay; Birtukan Cinnor; Chetan Mittal; Violette C. Simon; Paul Menard-Katcher; Sachin Wani


Gastroenterology | 2018

1082 - Geographic Variability in Surveillance Practices and Use of Advanced Imaging Modalities (Aims) in Barrett's Esophagus (Be): A Survey Study of International Experts

Jorge D. Machicado; Samuel Han; Violette C. Simon; Bashar J. Qumseya; Shahnaz Sultan; Sri Komanduri; Amit Rastogi; V. Raman Muthusamy; Vladimir M. Kushnir; Rehan Haidry; Rajvinder Singh; Rena Yadlapati; Krish Ragunath; Hazem T. Hammad; Nicholas J. Shaheen; Sachin Wani

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Sachin Wani

University of Colorado Boulder

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Samuel Han

Anschutz Medical Campus

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Dayna S. Early

Washington University in St. Louis

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Brian C. Brauer

University of Colorado Denver

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Steven A. Edmundowicz

University of Colorado Denver

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Vladimir M. Kushnir

Washington University in St. Louis

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