Positron-emission tomography for hepatocellular carcinoma: Current status and future prospects

Abstract

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer mortality worldwide. Various imaging modalities provide important information about HCC for its clinical management. Since positron-emission tomography (PET) or PET-computed tomography was introduced to the oncologic setting, it has played crucial roles in detecting, distinguishing, accurately staging, and evaluating local, residual, and recurrent HCC. PET imaging visualizes tissue metabolic information that is closely associated with treatment. Dynamic PET imaging and dual-tracer have emerged as complementary techniques that aid in various aspects of HCC diagnosis. The advent of new radiotracers and the development of immuno-PET and PET-magnetic resonance imaging have improved the ability to detect lesions and have made great progress in treatment surveillance. The current PET diagnostic capabilities for HCC and the supplementary techniques are reviewed herein.

Keywords: Hepatocellular carcinoma; Immuno-positron emission tomography; Positron-emission tomography; Radiotracer.

Figure 1

2-Deoxy-2-(¹⁸F)fluoro-D-glucose positron-emission tomography-computed tomography detected tumor recurrence after intervention therapy in a 58-year-old male patient with hepatocellular carcinoma. A: Cross-sectional computed tomography (CT) image showing a large sheet of lipiodol deposition in the right lobe of live after HCC intervention therapy; B: Cross-sectional positron-emission tomography (PET-CT) fusion image showing increased ¹⁸F-FDG uptake in and around the area of lipiodol deposition (blue arrow); the size of the lesion was 5.8 × 13.3 cm; C: Cross-sectional PET image showing increased ¹⁸F-FDG uptake in the right lobe of the liver; D: Maximum intensity projection image showing increased ¹⁸F-FDG uptake in the right lobe of the liver. ¹⁸F-FDG: 2-deoxy-2-(¹⁸F)fluoro-D-glucose; CT: Computed tomography; PET: Positron-emission tomography.

Figure 2

¹¹C-choline positron-emission tomography-computed tomography detected a tumor that was missed on conventional 2-deoxy-2-(¹⁸F)fluoro-D-glucose positron-emission tomography-computed tomography in a 58-year-old patient with hepatocellular carcinoma. A-D: 2-deoxy-2-(¹⁸F)fluoro-D-glucose positron-emission tomography-computed tomography (¹⁸F-FDG PET-CT) showed that there was no increased ¹⁸F-FDG uptake in the liver; E-H: ¹¹C-choline (¹¹C-CHOL) PET-CT showed focal increased ¹¹C-CHOL uptake in the upper segment of the anterior lobe of the liver, and the size of the lesion was 1.2 × 1.3 cm (blue arrow in F and G). Pathological examination confirmed well-differentiated hepatocellular carcinoma. ¹⁸F-FDG: 2-deoxy-2-(¹⁸F)fluoro-D-glucose; CT: Computed tomography; PET: Positron-emission tomography; ¹¹C-CHOL: ¹¹C-choline.

Figure 3

Early dynamic 2-deoxy-2-(¹⁸F)fluoro-D-glucose positron-emission tomography-computed tomography detected a tumor that was missed on conventional 2-deoxy-2-(¹⁸F)fluoro-D-glucose positron-emission tomography-computed tomography in a 64-year-old patient with hepatocellular carcinoma. A-D: 2-deoxy-2-(¹⁸F)fluoro-D-glucose positron-emission tomography-computed tomography (¹⁸F-FDG PET-CT) showed that there was no increased ¹⁸F-FDG uptake in the lesion on conventional ¹⁸F-FDG PET-CT; E-H: Early dynamic ¹⁸F-FDG PET-CT showed focal ¹⁸F-FDG hyperperfusion in the upper segment of the anterior lobe of the liver, and the size of the lesion was 1.7 × 1.9 cm (blue arrow in F and G). ¹⁸F-FDG: 2-deoxy-2-(¹⁸F)fluoro-D-glucose; CT: Computed tomography; PET: Positron-emission tomography.