title: Clinical strategies for differentiating autoimmune pancreatitis from pancreatic malignancy to avoid unnecessary surgical resection.
abstract: OBJECTIVE
  The study aimed to determine a practical strategy for differentiating between autoimmune pancreatitis (AIP) and pancreatic malignancy in order to avoid unnecessary surgical resection.
  
  
  METHODS
  Altogether, 19 patients with AIP or other pancreatic diseases underwent routine examinations including liver function test and carbohydrate antigen 19-9, computed tomography and/or magnetic resonance imaging. Serum immunoglobulin G (IgG) and/or IgG4 was determined in patients with clinically suspected or pathologically proven AIP. Patients with suspected AIP either received diagnostic steroid therapy or laparotomy (if malignant tumors could not be excluded). Surgery was not performed in patients with a definite diagnosis of AIP by fast intraoperative frozen biopsy. Those with confirmed AIP received steroid treatment.
  
  
  RESULTS
  In total, 15 cases were finally confirmed as AIP with eight diagnosed preoperatively, five confirmed by surgical pathology (preoperatively misdiagnosed) and two by intraoperative biopsy. Of these 15 patients with AIP and one without AIP, 14 had elevated serum γ-globulin levels. It was proven by subsequent antibody tests that serum IgG or IgG4 were simultaneously increased.
  
  
  CONCLUSIONS
  Elevated serum γ-globulin level can be used as a preoperative sentinel indicator for differentiating between IgG4-related AIP and pancreatic malignancy. Serum IgG or IgG4 tests should be further performed in those with elevated serum γ-globulin level, which helps to identify AIP in order to avoid unnecessary operation.
authors.affiliation: Department of General Surgery, Zhongshan Hospital, Fudan University, Shanghai, China.
authors.forename: Wen Chuan
authors.initials: WC
authors.lastname: Wu
authors.forename: Xiu Zhong
authors.initials: XZ
authors.lastname: Yao
authors.forename: Da Yong
authors.initials: DY
authors.lastname: Jin
authors.forename: Dan Song
authors.initials: DS
authors.lastname: Wang
authors.forename: Wen Hui
authors.initials: WH
authors.lastname: Lou
authors.forename: Xin Yu
authors.initials: XY
authors.lastname: Qin
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D001327:Autoimmune Diseases / Q000175:diagnosis* / Q000188:drug therapy / Q000601:surgery; D015415:Biomarkers / Q000097:blood; D001706:Biopsy; D018395:CA-19-9 Antigen / Q000097:blood; D003937:Diagnosis, Differential; D005260:Female; D005938:Glucocorticoids / Q000627:therapeutic use; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010179:Pancreas / Q000473:pathology; D010180:Pancreatectomy; D010190:Pancreatic Neoplasms / Q000175:diagnosis*; D050500:Pancreatitis, Chronic / Q000175:diagnosis* / Q000188:drug therapy / Q000601:surgery; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D019564:Unnecessary Procedures; D005719:gamma-Globulins / Q000032:analysis
chemical_list: D015415:Biomarkers; D018395:CA-19-9 Antigen; D005938:Glucocorticoids; D007074:Immunoglobulin G; D005719:gamma-Globulins
keywords: autoimmune pancreatitis; immunoglobulin G; operation; pancreatic neoplasms; γ-globulin