Contrast Agents for Hepatocellular Carcinoma Imaging: Value and Progression

Abstract

Hepatocellular carcinoma (HCC) has the third-highest incidence in cancers and has become one of the leading threats to cancer death. With the research on the etiological reasons for cirrhosis and HCC, early diagnosis has been placed great hope to form a favorable prognosis. Non-invasive medical imaging, including the associated contrast media (CM)-based enhancement scan, is taking charge of early diagnosis as mainstream. Meanwhile, it is notable that various CM with different advantages are playing an important role in the different imaging modalities, or even combined modalities. For both physicians and radiologists, it is necessary to know more about the proper imaging approach, along with the characteristic CM, for HCC diagnosis and treatment. Therefore, a summarized navigating map of CM commonly used in the clinic, along with ongoing work of agent research and potential seeded agents in the future, could be a needed practicable aid for HCC diagnosis and prognosis.

Keywords: CECT; MRI; contrast media (CM); hepatocellular carcinoma (HCC); ultrasound.

Figure 1

Images of a man in his eighties with a pathological diagnosis of moderately differentiated hepatocellular carcinoma (HCC) and had a history of hepatitis (C) At the Sonazoid-enhanced ultrasound (US), the liver lesion at a size of 43 mm with a thin halo located at segment III was observed on B-mode US (A). It was rapidly enhanced in the arterial phase (wash-in) (B), started to fade (wash-out) in portal phase (C), and was totally exhausted in the post-vascular phase (D). At Gd-EOB-DTPA-enhanced MRI, the lesion was hypointense on T1-weighted image (E), with the typical characteristics of wash-in and wash-out from arterial phase, portal phase, to delayed phase (F–H). It showed hyperintensity on T2-weighted image (I). At iodine agent-enhanced CT, it has low-density before enhancement (J). It also showed wash-in and wash-out from arterial phase, portal phase, to delayed phase (K–M). Finally, the gross specimen vividly reflected the morphological information of tumor (N). Arrowheads indicate the margin of the HCC lesion.

Figure 2

Images of a man in his sixties with a pathological diagnosis of poorly to moderately differentiated hepatocellular carcinoma (HCC) and had a history of cirrhosis. At the Sonazoid-enhanced ultrasound (US), the liver lesion was heterogeneous hyperechoic with the indistinct margin on B-mode US (A). It was rapidly enhanced in the arterial phase (wash-in) (B), still iso-echoic in portal phase (C), and was totally exhausted in the post-vascular phase (D). At Gd-EOB-DTPA-enhanced MRI, the lesion was hypointense on T1-weighted image (F), with uncharacteristic wash-in and delayed wash-out from arterial phase to delayed phase (G, H). It showed hyperintensity on T2-weighted image (I). The contrast media (CM) were totally exhausted till the hepatobiliary phase (J). The gross specimen indicated the heterogeneous pathological differentiation of HCC (E). Arrowheads indicate the margin of the HCC lesion.

Figure 3

Sonazoid-enhanced ultrasound (US) images of a man in his seventies with a pathological diagnosis of moderately differentiated hepatocellular carcinoma (HCC), who had a history of hepatitis C. The tumor was 70mm. Consecutive lateral images of the tumor remarkably illumed the irregular margin on the three-dimensional (3D) US, which was obtained by auto-sweep 3D scanning in the post-vascular phase. Tomographic ultrasound images in plane A, which can be translated from front to rear, with a slice distance of 4.8 mm. Arrowheads indicate the margin of the HCC lesion.

Figure 4

Images of a man in his seventies with a pathological diagnosis of moderately differentiated hepatocellular carcinoma (HCC) and had a history of cirrhosis and HCC. The hepatobiliary phase of EOBMRI (right side), as the reference, was combined with conventional grayscale US (left side), displayed an 8-mm indistinctive hypointense area (the triangular arrow) in segment V on the same screen for the fusion imaging (A). The extrasmall lesion was hypervascular in the arterial phase of Sonazoid-enhanced ultrasound (US) (B), while the post-vascular phase indicated it to be a slightly hypoechoic area (C). Pathway guidance was ready for radiofrequency ablation (RFA) needle manipulation on real-time US (B–D), along with tracking for the metallic needle tip (the curved arrow) (D). The contrast-enhanced US (CEUS) evaluated the target ablation area to be non-enhanced after RFA (E). Arrows indicate the margin of the bigger HCC lesion, which was previously treated by RFA. And Arrowheads indicate the margin of the extrasmall HCC lesion.