title: Biliary intraepithelial neoplasia: an international interobserver agreement study and proposal for diagnostic criteria.
abstract: Cholangiocarcinoma of the intrahepatic and extrahepatic bile ducts develops through a multistep histopathologic sequence. Premalignant or non-invasive neoplastic lesions of bile ducts have been historically called biliary dysplasia or atypical biliary epithelium. To this date, no standard terminology or classification system has been offered for these lesions. In 2005, a conceptual framework and diagnostic criteria for biliary intraepithelial neoplasia (BilIN) were proposed using the livers of patients with hepatolithiasis. We report herein an international interobserver agreement study on the diagnosis of biliary non-invasive neoplastic lesions with the goal to obtain a consensus on the terminology and grading. Seventeen pathologists from the United States, Europe and Asia participated in this study. They shared a digital file containing histological pictures of 30 foci of non-invasive neoplastic lesions selected from the biliary system of patients suffering from primary sclerosing cholangitis, choledochal cyst or hepatolithiasis. In the criteria, we proposed in 2005, BilIN was classified into three categories based on the degree of atypia: BilIN-1, BilIN-2 and BilIN-3. In this study, consensus was reached for the terminology of BilIN and the three-grade classification system. Interobserver agreement on the diagnosis was moderate (kappa-value=0.45). On the basis of the suggestions and opinions obtained from the 17 participants, the original criteria for BilIN were revised. We now propose a new consensus classification of BilIN that may assist in allowing a more uniform terminology for the diagnosis of biliary non-invasive neoplastic lesions. This classification should help to advance clinical and research applications.
authors: Department of Human Pathology, Kanazawa University Graduate School of Medicine, Kanazawa, Japan.
authors: Yoh
authors: Y
authors: Zen
authors: N Volkan
authors: NV
authors: Adsay
authors: Krystof
authors: K
authors: Bardadin
authors: Romano
authors: R
authors: Colombari
authors: Linda
authors: L
authors: Ferrell
authors: Hironori
authors: H
authors: Haga
authors: Seung-Mo
authors: SM
authors: Hong
authors: Prodromos
authors: P
authors: Hytiroglou
authors: Günter
authors: G
authors: Klöppel
authors: Gregory Y
authors: GY
authors: Lauwers
authors: Dirk J
authors: DJ
authors: van Leeuwen
authors: Kenji
authors: K
authors: Notohara
authors: Kiyoko
authors: K
authors: Oshima
authors: Alberto
authors: A
authors: Quaglia
authors: Motoko
authors: M
authors: Sasaki
authors: Fausto
authors: F
authors: Sessa
authors: Arief
authors: A
authors: Suriawinata
authors: Wilson
authors: W
authors: Tsui
authors: Yutaka
authors: Y
authors: Atomi
authors: Yasuni
authors: Y
authors: Nakanuma
mesh_terms: D017734:Bile Ducts, Extrahepatic / Q000473:pathology; D001653:Bile Ducts, Intrahepatic / Q000473:pathology; D001661:Biliary Tract Neoplasms / Q000145:classification / Q000175:diagnosis* / Q000473:pathology; D002278:Carcinoma in Situ / Q000145:classification / Q000175:diagnosis* / Q000473:pathology; D015209:Cholangitis, Sclerosing / Q000473:pathology; D015529:Choledochal Cyst / Q000473:pathology; D006801:Humans; D007391:International Cooperation; D020347:Lithiasis / Q000473:pathology; D008107:Liver Diseases / Q000473:pathology; D009626:Terminology as Topic