title: A case of marginal zone B cell lymphoma mimicking IgG4-related dacryoadenitis and sialoadenitis.
abstract: BACKGROUND
  IgG4-related dacryoadenitis and sialoadenitis (IgG4-DS), so-called Mikulicz's disease, is characterized by elevated serum IgG4 and infiltration of IgG4-positive plasma cells in glandular tissues. Recently, several studies reported both malignant lymphoma developed on the background of IgG4-associated conditions and IgG4-producing malignant lymphoma (non-IgG4-related disease).
  
  
  METHODS
  We report on the case of a 70-year-old man who was strongly suspected IgG4-DS because of high serum IgG4 concentration (215 mg/dl) and bilateral swelling of parotid and submandibular glands. Biopsies of cervical lymph node and a portion of submandibular gland were performed. These histopathological findings subsequently confirmed a diagnosis of marginal zone B cell lymphoma.
  
  
  CONCLUSIONS
  Differential diagnosis of IgG4-DS is necessary from other disorders, including Sjögren's syndrome, sarcoidosis, Castleman's disease, Wegener's granulomatosis, lymphoma, and cancer. We suggest that biopsy of swollen lesions is important for a definitive diagnosis of IgG4-DS and discuss the mechanism of development in this case.
authors.affiliation: Section of Oral and Maxillofacial Oncology, Division of Maxillofacial Diagnostic and Surgical Sciences, Faculty of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan. miho-o@dent.kyushu-u.ac.jp.
authors.forename: Miho
authors.initials: M
authors.lastname: Ohta
authors.affiliation: Section of Oral and Maxillofacial Oncology, Division of Maxillofacial Diagnostic and Surgical Sciences, Faculty of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan. moriyama@dent.kyushu-u.ac.jp.
authors.forename: Masafumi
authors.initials: M
authors.lastname: Moriyama
authors.affiliation: Section of Oral and Maxillofacial Oncology, Division of Maxillofacial Diagnostic and Surgical Sciences, Faculty of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan. ygoto@dent.kyushu-u.ac.jp.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Goto
authors.affiliation: Section of Oral and Maxillofacial Oncology, Division of Maxillofacial Diagnostic and Surgical Sciences, Faculty of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan. skawano@dent.kyushu-u.ac.jp.
authors.forename: Shintaro
authors.initials: S
authors.lastname: Kawano
authors.affiliation: Section of Oral and Maxillofacial Oncology, Division of Maxillofacial Diagnostic and Surgical Sciences, Faculty of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan. althair@dent.kyushu-u.ac.jp.
authors.forename: Akihiko
authors.initials: A
authors.lastname: Tanaka
authors.affiliation: Section of Oral and Maxillofacial Oncology, Division of Maxillofacial Diagnostic and Surgical Sciences, Faculty of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan. tmaehara@dent.kyushu-u.ac.jp.
authors.forename: Takashi
authors.initials: T
authors.lastname: Maehara
authors.affiliation: Section of Oral and Maxillofacial Oncology, Division of Maxillofacial Diagnostic and Surgical Sciences, Faculty of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan. s.furukawa@dent.kyushu-u.ac.jp.
authors.forename: Sachiko
authors.initials: S
authors.lastname: Furukawa
authors.affiliation: Section of Oral and Maxillofacial Oncology, Division of Maxillofacial Diagnostic and Surgical Sciences, Faculty of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan. junno@dent.kyushu-u.ac.jp.
authors.forename: Jun-Nosuke
authors.initials: JN
authors.lastname: Hayashida
authors.affiliation: Laboratory of Oral Pathology, Division of Maxillofacial Diagnostic and Surgical Sciences, Faculty of Dental Science, Kyushu University, Higashi-ku, Fukuoka, Japan. kiyo@dent.kyushu-u.ac.jp.
authors.forename: Tamotsu
authors.initials: T
authors.lastname: Kiyoshima
authors.affiliation: Department of Oral and Maxillofacial Radiology, Kyushu University Hospital, Higashi-ku, Fukuoka, Japan. shimizu@rad.dent.kyushu-u.ac.jp.
authors.forename: Mayumi
authors.initials: M
authors.lastname: Shimizu
authors.affiliation: Center for Cellular and Molecular Medicine, Kyushu University Hospital, Higashi-ku, Fukuoka, Japan. yarinobu@cancer.med.kyushu-u.ac.jp.
authors.forename: Yojiro
authors.initials: Y
authors.lastname: Arinobu
authors.affiliation: Section of Oral and Maxillofacial Oncology, Division of Maxillofacial Diagnostic and Surgical Sciences, Faculty of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan. seiji@dent.kyushu-u.ac.jp.
authors.forename: Seiji
authors.initials: S
authors.lastname: Nakamura
mesh_terms: D000368:Aged; D005871:Castleman Disease / Q000097:blood / Q000175:diagnosis* / Q000601:surgery; D003607:Dacryocystitis / Q000097:blood / Q000175:diagnosis* / Q000601:surgery; D003937:Diagnosis, Differential; D014890:Granulomatosis with Polyangiitis / Q000097:blood / Q000175:diagnosis* / Q000601:surgery; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D018442:Lymphoma, B-Cell, Marginal Zone / Q000097:blood / Q000175:diagnosis* / Q000601:surgery; D008297:Male; D008882:Mikulicz' Disease / Q000097:blood / Q000175:diagnosis* / Q000601:surgery; D011379:Prognosis; D012793:Sialadenitis / Q000097:blood / Q000175:diagnosis* / Q000601:surgery; D012859:Sjogren's Syndrome / Q000097:blood / Q000175:diagnosis* / Q000601:surgery
chemical_list: D007074:Immunoglobulin G