title: A rare case of IgG4-related systemic disease manifesting with pancreatic head mass mimicking borderline resectable cancer.
abstract: BACKGROUND
  Autoimmune pancreatitis (AIP) is a rare pancreatic disorder among chronic pancreatitis that can mimick pancreatic cancer (PC). Patients with type 1 AIP usually present obstructive jaundice associated with high level of IgG4 in serum and a pancreatic mass at radiological imaging; these disorders may be associated with other organs lesions presenting the same histopathological features, and in these cases AIP should be considered a pancreatic localization of an IgG4-related systemic disease.
  
  
  METHODS
  We report the case of a young man with initial suspect of PC to be treated with surgery, and final diagnosis of AIP in the context of an IgG4-related systemic disease.
  
  
  CONCLUSIONS
  Because of its similar features, several algorithms have been proposed for AIP diagnosis, based on combination of clinical/serological and radiological criteria. However, histology represents the only way to obtain definitive diagnosis, even if sometimes it is difficult to obtain biological samples.
  
  
  CONCLUSIONS
  IgG4-related systemic disease must be taken into account among differential diagnosis during the workup for PC, in order to avoid unnecessary surgery.
authors.affiliation: Department of Surgery, Molinette Hospital, Turin, Italy. Electronic address: afranchello@cittadellasalute.to.it.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Franchello
authors.affiliation: Department of Surgery, Molinette Hospital, Turin, Italy.
authors.forename: Federica
authors.initials: F
authors.lastname: Gonella
authors.affiliation: Department of Surgery, Molinette Hospital, Turin, Italy.
authors.forename: Donata
authors.initials: D
authors.lastname: Campra
authors.affiliation: Department of Radiology, Molinette Hospital, Turin, Italy.
authors.forename: Giorgio
authors.initials: G
authors.lastname: Limerutti
authors.affiliation: Department of Gastroenterology, Molinette Hospital, Turin, Italy.
authors.forename: Mauro
authors.initials: M
authors.lastname: Bruno
authors.affiliation: Department of Gastroenterology, Molinette Hospital, Turin, Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: De Angelis
authors.affiliation: Department of Surgery, Molinette Hospital, Turin, Italy.
authors.forename: Davide
authors.initials: D
authors.lastname: Cassine
authors.affiliation: Department of Surgery, Molinette Hospital, Turin, Italy.
authors.forename: Gianruggero
authors.initials: G
authors.lastname: Fronda
authors.affiliation: Department of Surgery, Molinette Hospital, Turin, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Silvestri
keywords: Autoimmune pancreatitis; IgG4-related disease; Pancreatic cancer