The clinical value of 18F-FDG PET/CT for investigating unexplained serum AFP elevation following interventional therapy for hepatocellular carcinom.

The goal of this study was to assess the clinical usefulness of 18F-FDG PET/ CT for investigating unexplained serum AFP elevation following interventional therapy such as transarterial chemoembolization (TAE) or radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC).A retrospective study was conducted involving 18 HCC patients (9 men and 9 women; age, 42-67 years) who underwent 18F-FDG PET/CT for evaluation of AFP without evidence of HCC recurrence on multiphasic abdominal CT after TAE or RFA treatment. The results of the 18F-FDG PET/CT were compared with histological, radiological and clinical follow-up.Among 18 patients, 14 patients demonstrated HCC recurrence (10 intrahepatic, 3 extrahepatic and 1 intrahepatic/extrahepatic). Metastatic foci were found in the lung (1 patient), bone (1 patient), lymph node (1 patient), and adrenal gland (1 patient). The 18F-FDG PET/CT identified seven intrahepatic and four extrahepatic lesions. Overall, the 18F-FDG PET/CT had nine true-positives, five false-negatives, four true-negatives and zero false-positives for the detection of HCC recurrence. The sensitivity, specificity and accuracy were 64%, 100% and 72%, respectively.When the multiphasic CT was normal, the 18F-FDG PET/CT was valuable to reveal intrahepatic tumor recurrence and/or extrahepatic metastases in patients with AFP elevation after interventional therapy for HCC.