title: Maximum standardized uptake value of fluorodeoxyglucose positron emission tomography/computed tomography is a prognostic factor in ovarian clear cell adenocarcinoma.
abstract: BACKGROUND
  Fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) is useful for diagnosing malignant tumors. Intracellular FDG uptake is measured as the standardized uptake value (SUV), which differs depending on tumor characteristics. This study investigated differences in maximum SUV (SUVmax) according to histologic type in ovarian epithelial cancer and the relationship of SUVmax with prognosis.
  
  
  METHODS
  This study included 80 patients with ovarian epithelial cancer based on histopathologic findings at surgery and who had undergone PET/CT before treatment. Maximum SUV on PET/CT of primary lesions and histopathology were compared based on histologic type, and the prognosis associated with different SUVmax was evaluated.
  
  
  RESULTS
  Clinical tumor stage was I in 35 patients, II in 8, III in 25, and IV in 12. Histologic type was serous adenocarcinoma (AC) in 33 patients, clear cell AC in 27, endometrioid AC in 15, and mucinous AC in 5. Median SUVmax was lower in mucinous AC (2.76) and clear cell AC (4.9) than in serous AC (11.4) or endometrioid AC (11.4). Overall, median SUVmax was lower in clinical stage I (5.37) than in clinical stage ≥II (10.3). However, in both clear cell AC and endometrioid AC, when histologic evaluation was possible, no difference was seen between stage I and stage ≥II. Moreover, in clear cell AC, the 5-year survival rate was significantly higher in the low-SUVmax group (100%) than in the high-SUVmax group (43.0%, P = 0.009).
  
  
  CONCLUSIONS
  Maximum SUV on preoperative FDG-PET/CT in ovarian epithelial cancer differs according to histologic type. In clear cell AC, SUVmax may represent a prognostic factor.
authors.affiliation: Departments of *Gynecologic Oncology and †Diagnostic Radiology, National Hospital Organization, Shikoku Cancer Center, Matsuyama, Japan.
authors.forename: Haruhisa
authors.initials: H
authors.lastname: Konishi
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Takehara
authors.forename: Atsumi
authors.initials: A
authors.lastname: Kojima
authors.forename: Shinichi
authors.initials: S
authors.lastname: Okame
authors.forename: Yasuko
authors.initials: Y
authors.lastname: Yamamoto
authors.forename: Yuko
authors.initials: Y
authors.lastname: Shiroyama
authors.forename: Takashi
authors.initials: T
authors.lastname: Yokoyama
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Nogawa
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Sugawara
mesh_terms: D018262:Adenocarcinoma, Clear Cell / Q000000981:diagnostic imaging* / Q000378:metabolism; D000328:Adult; D000368:Aged; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000493:pharmacokinetics*; D006801:Humans; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods / Q000592:standards; D010051:Ovarian Neoplasms / Q000000981:diagnostic imaging* / Q000378:metabolism; D049268:Positron-Emission Tomography / Q000379:methods / Q000592:standards; D011379:Prognosis; D012016:Reference Values; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods / Q000592:standards
chemical_list: D019788:Fluorodeoxyglucose F18