title: Kikuchi-Fujimoto disease: PET/CT assessment of a rare cause of cervical lymphadenopathy.
abstract: OBJECTIVE
  Kikuchi-Fujimoto disease (KFD), formerly called subacute necrotizing lymphadenitis, is a rare cause of cervical lymphadenopathy. The purpose of this study was to evaluate the usefulness of FDG PET/CT for distinguishing KFD from non-Hodgkin lymphoma (NHL).
  
  
  METHODS
  Twenty-two patients with cervical lymphadenopathy (8 with KFD and 14 with NHL) underwent CT and FDG PET/CT scans to examine the cervical lymphadenopathy. Regional values of FDG uptake were evaluated using the standardized uptake value (SUV) and partial volume corrected SUV (corSUV) based on the count recovery coefficient. Tumor size (mm), SUV, and corSUV were compared among KFD, indolent NHL, and aggressive NHL.
  
  
  RESULTS
  KFD lesions tended to be smaller (13.8 ± 5.4 mm) than those of indolent (25.4 ± 11.8) and aggressive (29.7 ± 18.8) NHL, whereas there were no significant differences in size. As for SUV, a significant difference was observed only between indolent and aggressive (6.4 ± 1.5 and 17.3 ± 9.3, P < 0.05) NHL; however, KFD showed a significantly greater corSUV (23.8 ± 10.6) as compared with indolent NHL (9.2 ± 5.1, P < 0.05), which did not show a significant difference from aggressive NHL (21.4 ± 10.2). FDG PET/CT detected thoracoabdominal lesions in 2 patients (25%) with KFD.
  
  
  CONCLUSIONS
  KFD shows high FDG uptake for size, which may reflect the pathologic characteristics, including necrotizing lymphocytes and numerous histiocytes (macrophages) surrounding small necrotic foci. FDG PET/CT will be useful for detecting noncervical lesions of KFD and distinguishing KFD from NHLs using both SUV and corSUV.
authors.affiliation: Department of Radiology, University of Fukui, Fukui, Japan. awaji@u-fukui.ac.jp
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Tsujikawa
authors.forename: Tatsuro
authors.initials: T
authors.lastname: Tsuchida
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Imamura
authors.forename: Masato
authors.initials: M
authors.lastname: Kobayashi
authors.forename: Satoko
authors.initials: S
authors.lastname: Asahi
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Shimizu
authors.forename: Kazunobu
authors.initials: K
authors.lastname: Tsuji
authors.forename: Hidehiko
authors.initials: H
authors.lastname: Okazawa
authors.forename: Hirohiko
authors.initials: H
authors.lastname: Kimura
mesh_terms: D000293:Adolescent; D000328:Adult; D001692:Biological Transport; D003937:Diagnosis, Differential; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000378:metabolism; D020042:Histiocytic Necrotizing Lymphadenitis / Q000150:complications* / Q000175:diagnosis* / Q000000981:diagnostic imaging; D006801:Humans; D008206:Lymphatic Diseases / Q000209:etiology*; D008228:Lymphoma, Non-Hodgkin / Q000175:diagnosis; D008297:Male; D049268:Positron-Emission Tomography; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D002577:Uterine Cervical Diseases / Q000209:etiology*
chemical_list: D019788:Fluorodeoxyglucose F18