title: Positron emission tomography scanning in the evaluation of hepatocellular carcinoma.
abstract: OBJECTIVE
  18F-fluorodeoxyglucose uptake allows estimation of glucose metabolism by tumor cells using positron emission tomography (PET). We evaluated the role of PET imaging in the diagnosis of hepatocellular carcinoma.
  
  
  METHODS
  PET images were collected after intravenous injection of 8-12 mCi of 18F-FDG in 20 patients with hepatocellular carcinoma (HCC). PET tumor activity level was assessed on a scale of 1 to 4 compared to normal liver tissue. The PET score was compared with abdominal computerized tomography (CT) scan results and between tumors of different grades and differentiation.
  
  
  RESULTS
  Of the 20 patients studied, 11 (55%) had positive PET scans (PET score: 3 or 4) while nine (45%) were negative (PET score: 1 or 2). CT scan was positive in 18 patients (90%) and negative in two (10%). PET, however, revealed metastases in three patients that were not seen on CT. On pathological review, well-differentiated and low-grade tumors had lower PET scores. Comparison of the well-differentiated with the moderately- and poorly-differentiated tumors revealed a statistically significant difference. No statistical significance was observed between the moderately- and poorly-differentiated tumors or between different tumor grades and PET scores.
  
  
  CONCLUSIONS
  The sensitivity of PET in diagnosis of HCC was 55% compared to 90% for CT scanning, although only PET detected some tumors (including distant metastases). Well-differentiated and low tumor grades had lower activity on PET and correspondingly lower PET scores. PET imaging may help assess tumor differentiation and may be useful in the diagnosis and staging and prognostication of HCC as an adjunct to CT.
authors.affiliation: Department of Internal Medicine, Saint Louis University School of Medicine, MO 63104, USA.
authors.forename: M A
authors.initials: MA
authors.lastname: Khan
authors.forename: C S
authors.initials: CS
authors.lastname: Combs
authors.forename: E M
authors.initials: EM
authors.lastname: Brunt
authors.forename: V J
authors.initials: VJ
authors.lastname: Lowe
authors.forename: M K
authors.initials: MK
authors.lastname: Wolverson
authors.forename: H
authors.initials: H
authors.lastname: Solomon
authors.forename: B T
authors.initials: BT
authors.lastname: Collins
authors.forename: A M
authors.initials: AM
authors.lastname: Di Bisceglie
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging* / Q000473:pathology; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011859:Radiography; D012680:Sensitivity and Specificity; D014055:Tomography, Emission-Computed / Q000379:methods*