title: Risk of cancer in patients with autoimmune pancreatitis.
abstract: OBJECTIVE
  Although simultaneous occurrences of autoimmune pancreatitis (AIP) and cancer are occasionally observed, it remains largely unknown whether cancer and AIP occur independently or these disorders are interrelated. The aim of this study was to examine the relationship between AIP and cancer.
  
  
  METHODS
  We conducted a multicenter, retrospective cohort study. One hundred and eight patients who met the Asian diagnostic criteria for AIP were included in the study. We calculated the proportion, standardized incidence ratio (SIR), relative risk, and time course of cancer development in patients with AIP. We also analyzed the clinicopathological characteristics of AIP patients with cancer in comparison with those without cancer.
  
  
  RESULTS
  Of the 108 AIP patients, 18 cancers were found in 15 patients (13.9%) during the median follow-up period of 3.3 years. The SIR of cancer was 2.7 (95% confidence interval (CI) 1.4-3.9), which was stratified into the first year (6.1 (95% CI 2.3-9.9)) and subsequent years (1.5 (95% CI 0.3-2.8)) after AIP diagnosis. Relative risk of cancer among AIP patients at the time of AIP diagnosis was 4.9 (95% CI 1.7-14.9). In six of eight patients whose cancer lesions could be assessed before corticosteroid therapy for AIP, abundant IgG4-positive plasma cell infiltration was observed in the cancer stroma. These six patients experienced no AIP relapse after successful cancer treatment.
  
  
  CONCLUSIONS
  Patients with AIP are at high risk of having various cancers. The highest risk for cancer in the first year after AIP diagnosis and absence of AIP relapse after successful treatment of the coexisting cancers suggest that AIP may develop as a paraneoplastic syndrome in some patients.
authors: Department of Gastroenterology and Hepatology, Kyoto University Graduate School of Medicine, Kyoto, Japan.
authors: Masahiro
authors: M
authors: Shiokawa
authors: Yuzo
authors: Y
authors: Kodama
authors: Kenichi
authors: K
authors: Yoshimura
authors: Chiharu
authors: C
authors: Kawanami
authors: Jun
authors: J
authors: Mimura
authors: Yukitaka
authors: Y
authors: Yamashita
authors: Masanori
authors: M
authors: Asada
authors: Masataka
authors: M
authors: Kikuyama
authors: Yoshihiro
authors: Y
authors: Okabe
authors: Tetsuro
authors: T
authors: Inokuma
authors: Masaya
authors: M
authors: Ohana
authors: Hiroyuki
authors: H
authors: Kokuryu
authors: Kazuo
authors: K
authors: Takeda
authors: Yoshihisa
authors: Y
authors: Tsuji
authors: Ryuki
authors: R
authors: Minami
authors: Yojiro
authors: Y
authors: Sakuma
authors: Katsutoshi
authors: K
authors: Kuriyama
authors: Yuji
authors: Y
authors: Ota
authors: Wataru
authors: W
authors: Tanabe
authors: Takahisa
authors: T
authors: Maruno
authors: Akira
authors: A
authors: Kurita
authors: Yugo
authors: Y
authors: Sawai
authors: Norimitsu
authors: N
authors: Uza
authors: Tomohiro
authors: T
authors: Watanabe
authors: Hironori
authors: H
authors: Haga
authors: Tsutomu
authors: T
authors: Chiba
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001327:Autoimmune Diseases / Q000150:complications* / Q000175:diagnosis / Q000276:immunology; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology*; D010195:Pancreatitis / Q000150:complications* / Q000175:diagnosis / Q000276:immunology; D012189:Retrospective Studies; D018570:Risk Assessment; D013274:Stomach Neoplasms / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology; D013997:Time Factors; D055815:Young Adult
chemical_list: D007074:Immunoglobulin G