title: Prognostic importance of 18F-FDG uptake pattern of hepatocellular cancer patients who received SIRT.
abstract: OBJECTIVE
  The aim of the study was to evaluate the effect of 18F-FDG uptake pattern of liver lesions to treatment response of patients who received yttrium-90 (Y-90) selective internal radiation therapy (SIRT) for hepatocellular cancer (HCC).
  
  
  METHODS
  Nineteen patients (5F, 14M, mean age: 64.5 ± 14.7 years old, range: 57-73 years) who received SIRT treatment in our department for HCC between June 2008 and May 2011 were included in the study. All patients underwent 18F-FDG PET/CT before SIRT for evaluation of disease stage and metabolic activity of liver lesions. Patients were divided into 3 groups according to FDG uptake patterns of primary liver lesions (hypoactive, nonhomogenous, and focal intense). Progression-free survival (PFS) times of each group and patients with hepatic only and hepatic with extrahepatic disease were analyzed. Disease progression criteria were increase in tumor volume, progressive elevation of serum alpha-fetoprotein levels, and detection of extrahepatic metastases. Kaplan-Meier analysis was used for comparison of PFS times.
  
  
  RESULTS
  The mean treatment dose was calculated as 1.4 ± 1.0 GBq. While liver lesions of 4 patients were hypoactive in pretreatment 18F-FDG PET/CT, liver lesions of 6 and 9 patients had nonhomogenous and intense FDG uptake, respectively. Mean PFS time of patients who had hypoactive liver lesions was 5.25 ± 1.52 months. In patients who had liver lesions with nonhomogenous uptake, mean PFS time was 12.3 ± 2.6 months. Lastly, in patients with intense uptake in liver lesions, PFS time was calculated as 19.8 ± 5.0 months. Difference between each group was statistically significant (P = 0.017). There was no significant difference in the PFS of the patients with limited hepatic disease and patients with extrahepatic involvement.
  
  
  CONCLUSIONS
  In patients with unresectable HCC, higher SUVmax lesions unexpectedly had better PFS rates after SIRT, suggesting SIRT has a treatment advantage over other therapeutic options in these patients.
authors.affiliation: Department of Nuclear Medicine, Ankara University Medical School, Ankara, Turkey.
authors.forename: Ozlem N
authors.initials: ON
authors.lastname: Kucuk
authors.forename: Cigdem
authors.initials: C
authors.lastname: Soydal
authors.forename: Mine
authors.initials: M
authors.lastname: Araz
authors.forename: Sadik
authors.initials: S
authors.lastname: Bilgic
authors.forename: Erkan
authors.initials: E
authors.lastname: Ibis
mesh_terms: D000368:Aged; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D053208:Kaplan-Meier Estimate; D008099:Liver / Q000000981:diagnostic imaging; D008113:Liver Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000532:radiotherapy*; D008168:Lung / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011877:Radionuclide Imaging; D015996:Survival Rate; D015021:Yttrium Radioisotopes / Q000627:therapeutic use
chemical_list: D015021:Yttrium Radioisotopes; D019788:Fluorodeoxyglucose F18