title: A rare case of IgG4-related disease: a gastric mass, associated with regional lymphadenopathy.
abstract: BACKGROUND
  IgG4-related disease (IgG4-RD) is a newly recognized disorder, characterized by massive IgG4+ lymphocyte and plasma cell infiltration, storiform fibrosis, causing enlargement, nodules or thickening of the various organs, simultaneously or metachronously. Involvement of the gastrointestinal tract is very rare and can be presented as a diffuse wall thickening or polyp or mass-like lesion. Up to now, there have been reported only a few cases of isolated gastric IgG4-RD.
  
  
  METHODS
  We present an unusual case of IgG4-RD of the stomach with involvement of the regional lymph nodes, clinically manifested as a gastric cancer with related pyloric stenosis. The patient underwent distal gastrectomy, omentectomy and lymph node dissection. The postoperative serum IgG4 level was increased. The diagnosis was confirmed by immunohistochemical study.
  
  
  CONCLUSIONS
  In the most of the reported cases there was not sufficient data about the regional lymph nodal status, although the majority of the patients had been operated with presumptive diagnosis of gastric neoplasm. Our case is rare and valuable because it presents a gastric IgG4-related lesion larger than all previously reported in literature, and IgG4-related lymphadenopathy, confirmed histologically, which contributes to better knowledge of the disease.
authors.affiliation: Department of General and Hepato-pancreatic Surgery, Medical University of Sofia, University Hospital "Alexandrovska", 1 Georgi Sofiiski Str, 1431, Sofia, Bulgaria.
authors.forename: Dimitar
authors.initials: D
authors.lastname: Bulanov
authors.affiliation: Department of General and Hepato-pancreatic Surgery, Medical University of Sofia, University Hospital "Alexandrovska", 1 Georgi Sofiiski Str, 1431, Sofia, Bulgaria. elena_arabadjieva@abv.bg.
authors.forename: Elena
authors.initials: E
authors.lastname: Arabadzhieva
authors.affiliation: Department of General and Hepato-pancreatic Surgery, Medical University of Sofia, University Hospital "Alexandrovska", 1 Georgi Sofiiski Str, 1431, Sofia, Bulgaria.
authors.forename: Sasho
authors.initials: S
authors.lastname: Bonev
authors.affiliation: Department of General and Hepato-pancreatic Surgery, Medical University of Sofia, University Hospital "Alexandrovska", 1 Georgi Sofiiski Str, 1431, Sofia, Bulgaria.
authors.forename: Atanas
authors.initials: A
authors.lastname: Yonkov
authors.affiliation: Department of General and Clinical Pathology, Medical University of Sofia, 2 Zdrave Str, 1431, Sofia, Bulgaria.
authors.forename: Diana
authors.initials: D
authors.lastname: Kyoseva
authors.affiliation: Department of General and Clinical Pathology, Medical University of Sofia, 2 Zdrave Str, 1431, Sofia, Bulgaria.
authors.forename: Tihomir
authors.initials: T
authors.lastname: Dikov
authors.affiliation: Department of General and Hepato-pancreatic Surgery, Medical University of Sofia, University Hospital "Alexandrovska", 1 Georgi Sofiiski Str, 1431, Sofia, Bulgaria.
authors.forename: Violeta
authors.initials: V
authors.lastname: Dimitrova
mesh_terms: D001327:Autoimmune Diseases / Q000175:diagnosis / Q000276:immunology*; D001706:Biopsy; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology*; D008198:Lymph Nodes / Q000473:pathology*; D000072281:Lymphadenopathy / Q000175:diagnosis / Q000276:immunology*; D008875:Middle Aged; D035583:Rare Diseases; D013272:Stomach Diseases / Q000175:diagnosis / Q000276:immunology*
chemical_list: D007074:Immunoglobulin G
keywords: IgG4-related disease; Plasma cells; Pseudotumor; Stomach; Surgical treatment