title: Usefulness of F-18 FDG PET/CT in the Evaluation of Early Treatment Response After Interventional Therapy for Hepatocellular Carcinoma.
abstract: OBJECTIVE
  This retrospective study investigated the usefulness of F-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) after interventional therapy for hepatocellular carcinoma (HCC).
  
  
  METHODS
  Between March 2007 and November 2010, 31 patients (24 men, 7 women; mean age, 61.8 ± 11.0 years) with 45 lesions underwent PET/CT within 1 month after interventional therapy for HCC. Twenty-six patients with 40 lesions underwent transcatheter arterial chemoembolization (TACE), two patients with 2 lesions underwent radiofrequency ablation (RFA), and three patients with 3 lesions underwent percutaneous ethanol injection therapy (PEIT). Patients with a history of previous interventional therapy were excluded. Visual analysis was graded as positive when FDG was observed as an eccentric, nodular, or infiltrative pattern, and negative in case of isometabolic, hypometabolic, or rim-shaped uptake. For quantitative analysis, the standardized uptake value (SUV) was measured by region of interest technique. Maximum SUV (SUVmax) was assessed, and the ratio of SUVmax of tumor to mean SUV of normal liver (TNR) was calculated. The patients were divided into two groups, with and without residual tumor, based on 6-month clinical follow-up with serum alpha-fetoprotein and contrast-enhanced abdominal CT.
  
  
  RESULTS
  Of the 45 lesions, 24 were classified in the residual tumor group and the other 21 lesions in the no residual tumor group. No residual tumor was detected after RFA or PEIT. By visual analysis, the respective values for sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 87.5, 71.4, 77.8, 83.3, and 80.0 %. However, there were no significant differences in the SUVmax and TNR between the two groups.
  
  
  CONCLUSIONS
  It is suggested that FDG PET/CT may play a role in the evaluation of early treatment response after interventional therapy for HCC. The results indicate that FDG PET/CT visual analysis may be more useful than quantitative analysis. Further prospective studies with a large number of patients and established protocol are needed to substantiate our results.
authors.affiliation: Department of Nuclear Medicine, Keimyung University, School of Medicine, 56 Dalseong-ro, Jung-gu, Daegu 700-712 Republic of Korea.
authors.forename: Sung Hoon
authors.initials: SH
authors.lastname: Kim
authors.affiliation: Department of Nuclear Medicine, Keimyung University, School of Medicine, 56 Dalseong-ro, Jung-gu, Daegu 700-712 Republic of Korea.
authors.forename: Kyoung Sook
authors.initials: KS
authors.lastname: Won
authors.affiliation: Department of Nuclear Medicine, Keimyung University, School of Medicine, 56 Dalseong-ro, Jung-gu, Daegu 700-712 Republic of Korea.
authors.forename: Byung Wook
authors.initials: BW
authors.lastname: Choi
authors.affiliation: Department of Nuclear Medicine, Keimyung University, School of Medicine, 56 Dalseong-ro, Jung-gu, Daegu 700-712 Republic of Korea.
authors.forename: Il
authors.initials: I
authors.lastname: Jo
authors.affiliation: Department of Nuclear Medicine, Keimyung University, School of Medicine, 56 Dalseong-ro, Jung-gu, Daegu 700-712 Republic of Korea.
authors.forename: Seok Kil
authors.initials: SK
authors.lastname: Zeon
authors.affiliation: Department of Internal Medicine, Keimyung University, School of Medicine, Daegu, Korea.
authors.forename: Woo Jin
authors.initials: WJ
authors.lastname: Chung
authors.affiliation: Department of Radiology, Keimyung University, School of Medicine, Daegu, Korea.
authors.forename: Jung Hyeok
authors.initials: JH
authors.lastname: Kwon
keywords: F-18 FDG; Hepatocellular carcinoma; Interventional therapy; Locoregional therapy; PET/CT; Response