title: Predictive Role of Functional Visceral Fat Activity Assessed by Preoperative F-18 FDG PET/CT for Regional Lymph Node or Distant Metastasis in Patients with Colorectal Cancer.
abstract: OBJECTIVE
  To investigate the role of functional visceral fat activity assessed by preoperative F-18 fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) in colorectal cancer (CRC) for predicting regional lymph node (LN) or distant metastasis.
  
  
  METHODS
  We evaluated 131 patients with newly diagnosed CRC. They all underwent pre-operative 18F-FDG PET/CT and surgery. Functional fat activity was measured by maximum standardized uptake value (SUVmax) using 18F-FDG PET/CT. Functional visceral fat activity was measured by SUVmax of visceral fat/SUVmax of subcutaneous fat (V/S) ratio. Mann-Whitney U test, χ2 test, Fisher's exact test, receiver-operating characteristic (ROC) analysis, Spearrman's correlation coefficient, and uni- and multivariate logistic regression statistical analyses were done.
  
  
  RESULTS
  Patients with higher V/S ratio displayed a significantly higher rate of regional LN (p = 0.004) and distant metastasis (p<0.001). In addition, V/S ratio was the only factor that was significantly associated with distant metastasis. An optimal cut-off V/S ratio of 1.88 was proposed for predicting distant metastasis with a sensitivity of 84.6% and specificity of 78.8% (area under the curve: 0.86; p<0.0001).
  
  
  CONCLUSIONS
  Functional visceral fat activity is significantly associated with distant metastasis in CRC patients. Furthermore, V/S ratio can be useful as a complementary factor in predicting distant metastasis.
authors: Department of Nuclear Medicine, College of Medicine, Korea University, Seoul, Korea.
authors: Kisoo
authors: K
authors: Pahk
authors: Department of Nuclear Medicine, College of Medicine, Korea University, Seoul, Korea.
authors: Seunghong
authors: S
authors: Rhee
authors: Department of Nuclear Medicine, College of Medicine, Korea University, Seoul, Korea.
authors: Sungeun
authors: S
authors: Kim
authors: Department of Nuclear Medicine, College of Medicine, Korea University, Seoul, Korea.
authors: Jae Gol
authors: JG
authors: Choe
mesh_terms: D000230:Adenocarcinoma / Q000097:blood / Q000000981:diagnostic imaging / Q000556:secondary*; D000368:Aged; D002097:C-Reactive Protein / Q000032:analysis; D015179:Colorectal Neoplasms / Q000097:blood / Q000000981:diagnostic imaging / Q000473:pathology*; D005260:Female; D005462:Fluorine Radioisotopes; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007249:Inflammation / Q000097:blood / Q000000981:diagnostic imaging; D050152:Intra-Abdominal Fat / Q000000981:diagnostic imaging*; D008207:Lymphatic Metastasis / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D050151:Subcutaneous Fat / Q000000981:diagnostic imaging; D014057:Tomography, X-Ray Computed
chemical_list: D005462:Fluorine Radioisotopes; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; D002097:C-Reactive Protein