Accuracy of endoscopic ultrasound elastography used for differential diagnosis of focal pancreatic masses: a multicenter study

A. Săftoiu; P. Vilmann; F. Gorunescu; J. Janssen; M. Hocke; M. Larsen; J. Iglesias-Garcia; P. Arcidiacono; U. Will; M. Giovannini; C. Dietrich; R. Havre; C. Gheorghe; C. McKay; D. I. Gheonea; T. Ciurea

doi:10.1055/s-0030-1256314

Endoscopy 2011; 43(7): 596-603
DOI: 10.1055/s-0030-1256314

Original article

Accuracy of endoscopic ultrasound elastography used for differential diagnosis of focal pancreatic masses: a multicenter study

A. Săftoiu¹ ^, ² , P. Vilmann² , F. Gorunescu³ , J. Janssen⁴ , M. Hocke⁵ , M. Larsen⁶ , J. Iglesias-Garcia⁷ , P. Arcidiacono⁸ , U. Will⁹ , M. Giovannini¹⁰ , C. Dietrich¹¹ , R. Havre¹² , C. Gheorghe¹³ , C. McKay¹⁴ , D. I. Gheonea¹ , T. Ciurea¹ , on behalf of the European EUS Elastography Multicentric Study Group

¹Gastroenterology Department, University of Medicine and Pharmacy, Craiova, Romania
²Department of Surgical Gastroenterology, Gentofte and Herlev Hospital, University of Copenhagen, Denmark
³Biostatistics and Computer Science, University of Medicine and Pharmacy, Craiova, Romania
⁴Helios Klinikum, University of Witten/Herdecke, Wuppertal, Germany
⁵Department of Internal Medicine II, Hospital Meiningen, Germany
⁶Center for Surgical Ultrasound, Department of Surgery, Odense University Hospital, Odense, Denmark
⁷Gastroenterology, University Hospital, Santiago de Compostela, Spain
⁸Gastroenterology and Gastrointestinal Endoscopy Unit, Vita Salute San Raffaele University, Milan, Italy
⁹Gastroenterology, SRH Wald-Klinikum, Gera, Germany
¹⁰Endoscopic Unit, Paoli-Calmettes Institut, Marseilles, France
¹¹Med. Klinik 2, Caritas-Krankenhaus Bad Mergentheim, Germany
¹²Institute of Medicine, University of Bergen and National Centre for Ultrasound in Gastroenterology, Haukeland University Hospital, Bergen, Norway
¹³Center of Gastroenterology and Hepatology, Fundeni Clinical Institute, Bucharest Romania
¹⁴Hepatobiliary Surgery, Glasgow Royal Infirmary, Glasgow, United Kingdom

Abstract

Background and study aims: Endoscopic ultrasound (EUS) elastography represents a new imaging procedure that might characterize the differences of hardness and strain between diseased tissue and normal tissue. The aim of this study was to assess the efficiency of EUS elastography for the differentiation of focal masses in chronic pancreatitis and pancreatic cancer.

Patients and methods: The study group comprised 258 patients with focal pancreatic masses included prospectively at 13 participating centers. Qualitative analysis of the diagnoses made by two expert doctors using all recorded video clips was performed in order to test the interobserver variability. A post-processing software analysis was used to examine the EUS elastography videos by calculating average-hue histograms of individual elastography images. The quantitative information was used to calculate intra-observer variability and the accuracy of the method.

Results: Qualitative analysis of the recorded videos revealed a kappa value of 0.72. Intra-observer variability analysis revealed that the single measure intraclass correlation ranged between 0.86 and 0.94. The average-hue histogram analysis of the data indicated a sensitivity of 93.4 %, a specificity of 66.0 %, a positive predictive value of 92.5 %, a negative predictive value of 68.9 %, and an overall accuracy of 85.4 %, based on a cut-off value of 175. Area under the receiver operating characteristic curve (AUROC) was 0.854 (P < 0.0001) with a confidence interval of 0.804 – 0.894.

Conclusion: The value of quantitative analysis of EUS elastography recordings was proven by good reproducibility of the videos, as well as good parameters of the AUROC analysis. (Clinical Trials.gov identifier: CT00909103).

Full Text

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A. SăftoiuMD, PhD

Research Center of Gastroenterology and Hepatology
University of Medicine and Pharmacy Craiova Romania

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Email: adry@umfcv.ro or adriansaftoiu@aim.com