[18F]fluoroacetate positron emission tomography for hepatocellular carcinoma and metastases: an alternative tracer for [11C]acetate?

Mol Imaging. 2012 Jun;11(3):229-39.

Abstract

[11C]Acetate (ACT) positron emission tomography/computed tomography (PET/CT) is useful in the detection of hepatocellular carcinoma (HCC). This study aimed to evaluate whether [18F]fluoroacetate (FAC) could be an alternative analogue of [11C]ACT for the diagnosis of HCC. [18F]FAC was synthesized using the precursor t-butyl 2-(methanesulfonyloxy)ethanoate. Five volunteer patients with known HCC were recruited after consent. Whole-body [18F]FAC PET/CT was performed at 20 minutes and 1 hour postinjection and compared to [11C]ACT PET/CT at 20 minutes postinjection to assess biodistribution and tumor uptake characteristics. Qualitative and semiquantitative analyses were performed with statistical correlations on the physiologic organs of accumulation and HCC lesions for both tracers. [18F]FAC was obtained with 99% radiochemical purity, and the reaction yield was 16.0% with 1-hour synthesis time. The biodistribution of [18F]FAC on PET/CT was significantly different from that of [11C]ACT (p < .05) by the lack of preferential uptake in any specific organ, particularly the pancreas, resembling the pattern of blood-pool retention although partly metabolized via the bowel. There was no significant defluorination, and none of the [11C]ACT-avid HCC lesions showed increased [18F]FAC activity. These were different from the results reported on other species. [18F]FAC may not be a potential alternative tracer for [11C]ACT in PET/CT evaluation of HCC in human subjects.

MeSH terms

  • Carcinoma, Hepatocellular / diagnostic imaging*
  • Carcinoma, Hepatocellular / pathology
  • Fluorine Radioisotopes* / pharmacokinetics
  • Humans
  • Liver Neoplasms / diagnostic imaging*
  • Liver Neoplasms / pathology
  • Multimodal Imaging / methods*
  • Neoplasm Metastasis / diagnostic imaging*
  • Positron-Emission Tomography*
  • Radiopharmaceuticals / pharmacokinetics
  • Tissue Distribution
  • Tomography, X-Ray Computed*

Substances

  • Fluorine Radioisotopes
  • Radiopharmaceuticals