title: A case of progressively transformed germinal center-type IgG4-related lymphadenopathy.
abstract: Progressively transformed germinal centers (PTGC), a lymph node process unfamiliar to most otolaryngologists, is a morphological variant of reactive lymphofollicular hyperplasia of lymph nodes. Immunoglobulin (Ig)G4-related disease (IgG4-RD) is a newly identified condition, characterized by hyper-IgG4-γ-globulinemia and mass-forming or hypertrophic lesions associated with infiltration of IgG4(+) plasma cells in the affected organs. Recently, a case study of PTGC was reported that fulfilled the diagnostic criteria of IgG4-RD (IgG4(+) PTGC) [1]. A 68-year-old male was referred to our hospital with swelling in the left submandibular region. Palpation revealed swollen lymph nodes, the largest of which measured 5cm in diameter. (18)F-fluorodeoxyglucose (FDG)-positron emission tomography/computed tomography identified lymphadenopathy with high (18)F-FDG uptake in the left submandibular region. We strongly suspected malignant lymphoma, and excisional biopsy of the submandibular lymph node was performed under general anesthesia. Pathological findings were consistent with IgG4(+) PTGC, and serological examination demonstrated elevated levels of IgG4. These findings were consistent with IgG4-RD. The patient did not have systemic lesions; therefore, he has not undergone corticosteroid therapy. IgG4(+) PTGC should be considered as a differential diagnosis for cervical lymphadenopathy by otolaryngologists as well as pathologists.
authors.affiliation: Department of Otolaryngology, Sapporo Medical University, Japan; Department of Otolaryngology, Hakodate Goryokaku Hospital, Japan. Electronic address: seki@sapmed.ac.jp.
authors.forename: Nobuhiko
authors.initials: N
authors.lastname: Seki
authors.affiliation: Department of Otolaryngology, Hakodate Goryokaku Hospital, Japan.
authors.forename: Norikazu
authors.initials: N
authors.lastname: Yamazaki
authors.affiliation: Department of Otolaryngology, Sapporo Medical University, Japan; Department of Otolaryngology, Hakodate Goryokaku Hospital, Japan.
authors.forename: Jun-ichi
authors.initials: J
authors.lastname: Koizumi
authors.affiliation: Department of Otolaryngology, Sapporo Medical University, Japan.
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Takano
authors.affiliation: Department of Otolaryngology, Sapporo Medical University, Japan.
authors.forename: Ayumi
authors.initials: A
authors.lastname: Abe
authors.affiliation: Pathology Center, Hakodate Goryokaku Hospital, Japan.
authors.forename: Tatsuru
authors.initials: T
authors.lastname: Ikeda
authors.affiliation: Department of Pathology, Teine Keijinkai Hospital, Japan.
authors.forename: Hiroko
authors.initials: H
authors.lastname: Noguchi
authors.affiliation: Department of Otolaryngology, Sapporo Medical University, Japan.
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Himi
mesh_terms: D000368:Aged; D018858:Germinal Center / Q000000981:diagnostic imaging* / Q000276:immunology / Q000473:pathology; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology*; D008198:Lymph Nodes / Q000000981:diagnostic imaging / Q000276:immunology / Q000473:pathology; D008206:Lymphatic Diseases / Q000175:diagnosis / Q000276:immunology; D008297:Male; D064847:Multimodal Imaging; D009333:Neck; D049268:Positron-Emission Tomography; D019310:Pseudolymphoma / Q000175:diagnosis* / Q000276:immunology; D014057:Tomography, X-Ray Computed
chemical_list: D007074:Immunoglobulin G
keywords: Follicular hyperplasia; IgG4-related disease; Progressively transformed germinal centers