title: The relationship between brown adipose tissue activity and neoplastic status: an (18)F-FDG PET/CT study in the tropics.
abstract: BACKGROUND
  Brown adipose tissue (BAT) has thermogenic potential. For its activation, cold exposure is considered a critical factor though other determinants have also been reported. The purpose of this study was to assess the relationship between neoplastic status and BAT activity by 2-deoxy-2-[(18)F]fluoro-D-glucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) in people living in the tropics, where the influence of outdoor temperature was low.
  
  
  METHODS
  (18)F-FDG PET/CT scans were reviewed and the total metabolic activity (TMA) of identified activated BAT quantified. The distribution and TMA of activated BAT were compared between patients with and without a cancer history. The neoplastic status of patients was scored according to their cancer history and (18)F-FDG PET/CT findings. We evaluated the relationships between the TMA of BAT and neoplastic status along with other factors: age, body mass index, fasting blood sugar, gender, and outdoor temperature.
  
  
  RESULTS
  Thirty of 1740 patients had activated BAT. Those with a cancer history had wider BAT distribution (p = 0.043) and a higher TMA (p = 0.028) than those without. A higher neoplastic status score was associated with a higher average TMA. Multivariate analyses showed that neoplastic status was the only factor significantly associated with the TMA of activated BAT (p = 0.016).
  
  
  CONCLUSIONS
  Neoplastic status is a critical determinant of BAT activity in patients living in the tropics. More active neoplastic status was associated with more vigorous TMA of BAT.
authors.affiliation: Department of Nuclear Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan.
authors.forename: Yung-Cheng
authors.initials: YC
authors.lastname: Huang
authors.forename: Tai-Been
authors.initials: TB
authors.lastname: Chen
authors.forename: Chien-Chin
authors.initials: CC
authors.lastname: Hsu
authors.forename: Shau-Hsuan
authors.initials: SH
authors.lastname: Li
authors.forename: Pei-Wen
authors.initials: PW
authors.lastname: Wang
authors.forename: Bi-Fang
authors.initials: BF
authors.lastname: Lee
authors.forename: Ching-Yuan
authors.initials: CY
authors.lastname: Kuo
authors.forename: Nan-Tsing
authors.initials: NT
authors.lastname: Chiu
mesh_terms: D002001:Adipose Tissue, Brown / Q000378:metabolism*; D000293:Adolescent; D000328:Adult; D000368:Aged; D050218:Body Fat Distribution; D002648:Child; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D015999:Multivariate Analysis; D009369:Neoplasms / Q000000981:diagnostic imaging* / Q000378:metabolism; D049268:Positron-Emission Tomography; D012189:Retrospective Studies; D013624:Taiwan; D014057:Tomography, X-Ray Computed; D014329:Tropical Climate; D055815:Young Adult
chemical_list: D019788:Fluorodeoxyglucose F18