title: 18F-fluoro-2-deoxy-D-glucose retention index as a prognostic parameter in patients with pancreatic cancer.
abstract: OBJECTIVE
  The objective of this study was to determine the most effective way to use dual-phase F-fluoro-2-deoxy-D-glucose (F-FDG) PET/computed tomography (CT) semiquantitative indices to predict prognosis in patients with pancreatic cancer and to guide treatment.
  
  
  METHODS
  Prognostic parameters were retrospectively analyzed in 40 patients with histologically proven pancreatic cancer who received F-FDG PET/CT at Ruijin Hospital. Maximum standardized uptake values (SUVs) were determined at 1 h (SUV1) and 2 h (SUV2) after F-FDG injection. The retention index (RI) was defined as the percentage change between SUV1 and SUV2.
  
  
  RESULTS
  RI less than 17% was explored as having a significant independent correlation with prolonged patient survival (P<0.05). Patients with tumor resection and RI less than 17% survived significantly longer than those with or without tumor resection and RI of 17% or higher (P<0.05). Neither SUV1, nor SUV2 showed any prognostic significance, but they did show a positive correlation with tumor diameter (P1<0.01; P2<0.05); RI had a strong positive correlation with tumor, node, and metastasis stage (P<0.01). Two factors were found to be associated with RI, including pancreatitis (P<0.05) and diabetes (P<0.01).
  
  
  CONCLUSIONS
  RI served as the most accurate parameter to predict disease prognosis in pancreatic cancer and to identify patients who could benefit from surgery. However, pancreatitis and diabetes had a potential impact on RI, reflecting the influence of tumor pathophysiological changes on the metabolism of glucose in pancreatic tumor cells. Therefore, further comprehensive analyses are required.
authors.affiliation: Department of Nuclear Medicine, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, People's Republic of China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Xi
authors.forename: Rui
authors.initials: R
authors.lastname: Guo
authors.forename: Jiajia
authors.initials: J
authors.lastname: Hu
authors.forename: Min
authors.initials: M
authors.lastname: Zhang
authors.forename: Xiangming
authors.initials: X
authors.lastname: Zhang
authors.forename: Biao
authors.initials: B
authors.lastname: Li
mesh_terms: D001692:Biological Transport; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D010190:Pancreatic Neoplasms / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000628:therapy; D049268:Positron-Emission Tomography; D011379:Prognosis; D016016:Proportional Hazards Models; D016019:Survival Analysis; D014057:Tomography, X-Ray Computed
chemical_list: D019788:Fluorodeoxyglucose F18