title: 18F-FDG PET in the detection of extrahepatic metastases from hepatocellular carcinoma.
abstract: BACKGROUND
  Positron emission tomography (PET) with 18F-fluoro-2-deoxy-D-glucose (18F-FDG) is useful in detecting distant metastases from a variety of malignancies. However, its efficiency in detecting distant metastases from hepatocellular carcinoma (HCC) has not been investigated. The aim of this study was to evaluate the usefulness of 18F-FDG PET for the detection of extrahepatic metastases from HCC.
  
  
  METHODS
  Nineteen patients suspected of having extrahepatic HCC underwent 18F-FDG PET. Fourteen patients (group A) had extrahepatic lesions, which were detected by conventional studies. In five patients (group B), conventional imaging showed no extra- or intrahepatic lesions, but the tumor marker levels were elevated. The PET results were compared with those obtained by histopathology or by clinical follow-up.
  
  
  RESULTS
  The detection rate of 18F-FDG PET was 83% (24 of 29 metastases) for extrahepatic metastases larger than 1 cm in greatest diameter and 13% (1 of 8 metastases) for lesions less than or equal to 1 cm. PET revealed two bone metastases not depicted by bone scan, and detected the nodal metastasis and intestinal metastases inconclusive on computed tomography. Extrahepatic lesions were resected in 5 patients of group A on the basis of PET findings. In all patients of group B, PET results were true negative for extrahepatic metastases, but HCCs were detected in the liver within 4 months in 4 patients. These were no false-positive lesions in either group.
  
  
  CONCLUSIONS
  This preliminary study suggested that 18F-FDG PET could provide additional information and contribute to the management of HCC patients suspected of having extrahepatic metastases.
authors.affiliation: Department of Radiology, Hamamatsu University School of Medicine, 1-20-1 Handayama, 431-3192, Hamamatsu, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Sugiyama
authors.forename: Harumi
authors.initials: H
authors.lastname: Sakahara
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Torizuka
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Kanno
authors.forename: Fumitoshi
authors.initials: F
authors.lastname: Nakamura
authors.forename: Masami
authors.initials: M
authors.lastname: Futatsubashi
authors.forename: Satoshi
authors.initials: S
authors.lastname: Nakamura
mesh_terms: D000368:Aged; D001859:Bone Neoplasms / Q000000981:diagnostic imaging / Q000556:secondary; D006528:Carcinoma, Hepatocellular / Q000556:secondary*; D005240:Feasibility Studies; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007414:Intestinal Neoplasms / Q000000981:diagnostic imaging / Q000556:secondary; D008113:Liver Neoplasms / Q000473:pathology*; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18