title: Possible association between IgG4-associated systemic disease with or without autoimmune pancreatitis and non-Hodgkin lymphoma.
abstract: OBJECTIVE
  IgG4-associated systemic disease (ISD) is a multiorgan fibroinflammatory disorder whose pancreatic manifestation is called autoimmune pancreatitis (AIP). We describe 3 patients who developed non-Hodgkin lymphoma during the follow-up of ISD.
  
  
  METHODS
  At our institution's pancreas clinic, we have prospectively and retrospectively examined patients with ISD with (n = 101) or without (n = 10) AIP (mean age, 59 years; 90 males and 21 females). We reviewed the medical records of all 111 patients to identify patients who developed non-Hodgkin lymphoma during the follow-up since their first presentation of ISD. Standardized incidence rate was calculated.
  
  
  RESULTS
  The 111 patients with ISD with or without AIP had 331 patient-years of observation during which 3 patients had a diagnosis of non-Hodgkin lymphoma 3 to 5 years after the diagnosis of ISD. In these patients who later developed lymphoma, ISD involved the pancreas (AIP) in 2 and salivary gland in 1. Non-Hodgkin lymphoma had extranodal involvement in all patients (liver [n = 2], adrenal glands [n=1], kidney [n= 1], and lung [n = 1]). Standardized incidence rate was 16.0 (95% confidence interval, 3.3-45.5).
  
  
  CONCLUSIONS
  We report 3 cases of non-Hodgkin lymphoma that developed during the follow-up of ISD suggesting that patients with ISD may be at an increased risk of developing non-Hodgkin lymphoma.
authors.affiliation: Department of Radiology, Mayo Clinic, Rochester, MN 55905, USA. takahashi.naoki@mayo.edu
authors.forename: Naoki
authors.initials: N
authors.lastname: Takahashi
authors.forename: Amaar H
authors.initials: AH
authors.lastname: Ghazale
authors.forename: Thomas C
authors.initials: TC
authors.lastname: Smyrk
authors.forename: Jayawant N
authors.initials: JN
authors.lastname: Mandrekar
authors.forename: Suresh T
authors.initials: ST
authors.lastname: Chari
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001327:Autoimmune Diseases / Q000150:complications* / Q000276:immunology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology*; D008228:Lymphoma, Non-Hodgkin / Q000175:diagnosis / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D010195:Pancreatitis / Q000150:complications* / Q000276:immunology; D012307:Risk Factors; D014057:Tomography, X-Ray Computed; D055815:Young Adult
chemical_list: D007074:Immunoglobulin G