title: Fluorine-18 fluorodeoxyglucose positron emission tomography predicts tumor differentiation, P-glycoprotein expression, and outcome after resection in hepatocellular carcinoma.
abstract: OBJECTIVE
  To investigate the diagnostic value of fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) for prediction of tumor differentiation, P-glycoprotein (P-gp) expression, and outcome in hepatocellular carcinoma (HCC) patients.
  
  
  METHODS
  Seventy HCC patients who underwent curative resection were prospectively enrolled in the study. FDG-PET was done 2 weeks preoperatively, and the standardized uptake value (SUV) and the tumor to nontumor SUV ratio (TNR) were calculated from FDG uptake. Tumor differentiation and P-gp expression were examined with H&E and immunohistochemical staining, respectively.
  
  
  RESULTS
  SUV and TNR were significantly higher in poorly differentiated HCCs than in well-differentiated (P = 0.001 and 0.002) and moderately differentiated HCCs (P < 0.0001 and P < 0.0001). The percentage P-gp-positive area was significantly higher in well-differentiated HCCs than in poorly differentiated (P < 0.0001) and moderately differentiated HCCs (P = 0.0001). Inverse correlations were found between SUV and P-gp expression (r = -0.44; P < 0.0001) and between TNR and P-gp expression (r = -0.47; P = 0.01). Forty-three (61.4%) patients had postoperative recurrence. The overall and disease-free survival rates in the high TNR (> or =2.0) group were significantly lower than in the low TNR (<2.0) group (P = 0.0001 and 0.0002). In multivariate analysis, a high alpha-fetoprotein level (risk ratio, 5.46; P = 0.003; risk ratio, 8.78; P = 0.006) and high TNR (risk ratio, 1.3; P = 0.03; risk ratio, 1.6; P = 0.02) were independent predictors of postoperative recurrence and overall survival.
  
  
  CONCLUSIONS
  The results suggest that preoperative FDG-PET reflects tumor differentiation and P-gp expression and may be a good predictor of outcome in HCC.
authors.affiliation: Department of Surgery and Diagnostic Imaging, Kyoto University Graduate School of Medicine, 54 Kawahara-cho, Syogoin, Sakyo-ku, Kyoto 606-8507, Japan.
authors.forename: Satoru
authors.initials: S
authors.lastname: Seo
authors.forename: Etsuro
authors.initials: E
authors.lastname: Hatano
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Higashi
authors.forename: Tadashi
authors.initials: T
authors.lastname: Hara
authors.forename: Masaharu
authors.initials: M
authors.lastname: Tada
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Tamaki
authors.forename: Keiko
authors.initials: K
authors.lastname: Iwaisako
authors.forename: Iwao
authors.initials: I
authors.lastname: Ikai
authors.forename: Shinji
authors.initials: S
authors.lastname: Uemoto
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000096:biosynthesis*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D006528:Carcinoma, Hepatocellular / Q000378:metabolism*; D002454:Cell Differentiation; D018572:Disease-Free Survival; D005260:Female; D019788:Fluorodeoxyglucose F18; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008113:Liver Neoplasms / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography / Q000379:methods*; D011446:Prospective Studies; D019275:Radiopharmaceuticals / Q000494:pharmacology*; D012306:Risk
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18