title: Incidence, clinical presentation and pathological features of benign sclerosing cholangitis of unknown origin masquerading as biliary carcinoma.
abstract: BACKGROUND
  Benign obstructions of the liver hilum are occasionally encountered in surgically resected cases. Some of these cases are pathologically classified as benign sclerosing cholangitis and are not clearly categorized. This study aims to elucidate the clinicopathological features of benign sclerosing cholangitis of unknown origin.
  
  
  METHODS
  Patients who had undergone surgery of the proximal bile duct from 1993 to 2008 on suspicion of proximal bile carcinoma were evaluated, then their clinical presentation, histopathological and immunohistochemical findings were retrospectively analyzed.
  
  
  RESULTS
  One hundred seventy-six patients underwent surgery during this period. Of these, five patients were diagnosed with benign sclerosing cholangitis of unknown origin. All five patients were middle-aged with no history of autoimmune disease. One patient died of recurrent cholangitis after surgery. Histopathologically, lymphoplasmacytic infiltrations were observed in all five cases. Among them, the clinicopathological findings of one patient were compatible with IgG4-related sclerosing cholangitis, and the other two patients had unusual histopathological findings with prominent lymph follicular formation.
  
  
  CONCLUSIONS
  Although patients with benign sclerosing cholangitis of unknown origin comprise a heterogeneous population, they can be further classified into subgroups. The response to immunosuppressive therapy, long-term prognosis and histological morphology of the disease should be considered in order to classify these cases of sclerosing cholangitis.
authors.affiliation: Division of Digestive Surgery, National Cancer Center Hospital East, 6-5-1 Kashiwanoha, Kashiwa, Chiba 277-8577, Japan. takfujit@east.ncc.go.jp
authors.forename: Takeo
authors.initials: T
authors.lastname: Fujita
authors.forename: Motohiro
authors.initials: M
authors.lastname: Kojima
authors.forename: Naoto
authors.initials: N
authors.lastname: Gotohda
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Takahashi
authors.forename: Toshio
authors.initials: T
authors.lastname: Nakagohri
authors.forename: Masaru
authors.initials: M
authors.lastname: Konishi
authors.forename: Atsushi
authors.initials: A
authors.lastname: Ochiai
authors.forename: Taira
authors.initials: T
authors.lastname: Kinoshita
mesh_terms: D000328:Adult; D000368:Aged; D001650:Bile Duct Neoplasms / Q000175:diagnosis*; D001652:Bile Ducts / Q000378:metabolism / Q000473:pathology*; D015209:Cholangitis, Sclerosing / Q000150:complications / Q000175:diagnosis / Q000453:epidemiology*; D002763:Cholecystectomy; D002779:Cholestasis / Q000175:diagnosis / Q000209:etiology / Q000601:surgery; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis; D007150:Immunohistochemistry; D015994:Incidence; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies
chemical_list: D007074:Immunoglobulin G