title: Utility of fluorodeoxyglucose positron emission tomography/computed tomography for early diagnosis and evaluation of disease activity of relapsing polychondritis: a case series and literature review.
abstract: OBJECTIVE
  Relapsing polychondritis (RPC) is relatively rare and early diagnosis is difficult. We investigated the utility of fluorodeoxyglucose (FDG)-PET/CT for the diagnosis of RPC and evaluation of disease activity.
  
  
  METHODS
  Five RPC patients undergoing FDG-PET/CT in our hospital between 2006 and 2012 were studied. Eight RPC cases examined by PET reported in the literature were also assessed. Data from a total of 13 patients were analysed.
  
  
  RESULTS
  Typical FDG accumulation was noted in the tracheobronchial trees of nine patients, the costal cartilage of five, joints of five, larynx of four, nasal cavity/paranasal sinuses of three, auricles of three, lymph nodes of three and the aorta of one. One patient showed nasal chondritis on a PET scan despite the absence of nasal changes on physical examination. Of five patients with costochondritis, four remained asymptomatic. Of nine patients with airway FDG accumulation, eight developed respiratory symptoms and all had CT abnormalities. In the other patient, airway FDG accumulation was evident despite the absence of airway symptoms and a lack of abnormalities in the respiratory function test and CT. PET also revealed bronchial chondritis in asymptomatic patients. The mean maximum standardized uptake values (SUVmax) of the upper and lower airways was 5.79 (s.d. 2.87) and 6.47 (s.d. 4.08), respectively. In five patients with a PET after treatment, FDG accumulation had diminished with symptomatic and inflammatory improvement.
  
  
  CONCLUSIONS
  FDG-PET/CT is a potentially powerful tool for the early diagnosis of RPC, especially in patients without easily biopsied organ involvement. This modality also facilitates evaluation of disease extent and disease activity during treatment.
authors.affiliation: Division of Rheumatic Diseases and Department of Radiology, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan. hiroyuki_yjp2005@yahoo.co.jp.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Yamashita
authors.affiliation: Division of Rheumatic Diseases and Department of Radiology, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Takahashi
authors.affiliation: Division of Rheumatic Diseases and Department of Radiology, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan.
authors.forename: Kazuo
authors.initials: K
authors.lastname: Kubota
authors.affiliation: Division of Rheumatic Diseases and Department of Radiology, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan.
authors.forename: Yo
authors.initials: Y
authors.lastname: Ueda
authors.affiliation: Division of Rheumatic Diseases and Department of Radiology, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Ozaki
authors.affiliation: Division of Rheumatic Diseases and Department of Radiology, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Yorifuji
authors.affiliation: Division of Rheumatic Diseases and Department of Radiology, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan.
authors.forename: Ei
authors.initials: E
authors.lastname: Bannai
authors.affiliation: Division of Rheumatic Diseases and Department of Radiology, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan.
authors.forename: Ryogo
authors.initials: R
authors.lastname: Minamimoto
authors.affiliation: Division of Rheumatic Diseases and Department of Radiology, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan.
authors.forename: Miyako
authors.initials: M
authors.lastname: Morooka
authors.affiliation: Division of Rheumatic Diseases and Department of Radiology, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Miyata
authors.affiliation: Division of Rheumatic Diseases and Department of Radiology, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan.
authors.forename: Momoko
authors.initials: M
authors.lastname: Okasaki
authors.affiliation: Division of Rheumatic Diseases and Department of Radiology, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Takahashi
authors.affiliation: Division of Rheumatic Diseases and Department of Radiology, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kaneko
authors.affiliation: Division of Rheumatic Diseases and Department of Radiology, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan.
authors.forename: Toshikazu
authors.initials: T
authors.lastname: Kano
authors.affiliation: Division of Rheumatic Diseases and Department of Radiology, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan.
authors.forename: Akio
authors.initials: A
authors.lastname: Mimori
mesh_terms: D000368:Aged; D042241:Early Diagnosis; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D011081:Polychondritis, Relapsing / Q000175:diagnosis* / Q000000981:diagnostic imaging; D049268:Positron-Emission Tomography; D014057:Tomography, X-Ray Computed
chemical_list: D019788:Fluorodeoxyglucose F18
keywords: cartilage; diagnostic imaging; ears; nose; radionuclide imaging; respiratory; throat