J Liver Cancer.  2023 Mar;23(1):143-156. 10.17998/jlc.2023.02.16.

Radiologic features of hepatocellular carcinoma related to prognosis

• Hwang SH
• Rhee H

• KMID: 2540827
• DOI: http://doi.org/10.17998/jlc.2023.02.16

Abstract

The cross-sectional imaging findings play a crucial role in the diagnosis of hepatocellular carcinoma (HCC). Recent studies have shown that imaging findings of HCC are not only relevant for the diagnosis of HCC, but also for identifying genetic and pathologic characteristics and determining prognosis. Imaging findings such as rim arterial phase hyperenhancement, arterial phase peritumoral hyperenhancement, hepatobiliary phase peritumoral hypointensity, non-smooth tumor margin, low apparent diffusion coefficient, and the LR-M category of the Liver Imaging-Reporting and Data System have been reported to be associated with poor prognosis. In contrast, imaging findings such as enhancing capsule appearance, hepatobiliary phase hyperintensity, and fat in mass have been reported to be associated with a favorable prognosis. Most of these imaging findings were examined in retrospective, single-center studies that were not adequately validated. However, the imaging findings can be applied for deciding the treatment strategy for HCC, if their significance can be confirmed by a large multicenter study. In this literature, we would like to review imaging findings related to the prognosis of HCC as well as their associated clinicopathological characteristics.

Keyword

Carcinoma, hepatocellular; Magnetic resonance imaging; Multidetector computed tomography; Prognosis

Figure

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  Figure 1. Hepatocellular carcinoma with fatty change in a 60-year-old woman. Approximately 1.8 cm non-rim arterial phase hyperenhancing hepatic nodule (arrow) (A) remains iso to slightly hyperintense in the hepatic parenchyma without washout appearance in the portal venous phase (B). In dual gradient-echo T1-weighted images (C, D), the signal intensity of the tumor decreased in the opposed-phase (arrowhead) (D) compared to the in-phase (C), suggesting the presence of intralesional fat. On pathologic examination, the lesion was Edmondson-Steiner grade I-II, which showed fatty changes in 60% of the tumor area.

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  Figure 2. Hepatocellular carcinoma (HCC) with rim arterial phase hyperenhancement and non-smooth tumor margin in a 61-year-old man. In pre-contrast (A), arterial (B), portal venous (C), and hepatobiliary (D) phase images of gadoxetate-enhanced magnetic resonance imaging, a 1.8 cm hepatic nodule shows rim-like peripheral hyperenhancement in the arterial phase (arrow). Note the non-smooth margins of the tumor. On pathological examination, the lesion was a poorly differentiated HCC with microvascular invasion.

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  Figure 3. Hepatocellular carcinoma showing low apparent diffusion coefficient and LR-M features in a 68-year-old man. An approximately 3 cm hepatic mass showing irregular rim hyperenhancement (arrow) in the arterial phase (A). The lesion displays high signal intensity on diffusion-weighted imaging (b=800) (B) and low signal intensity in the apparent diffusion coefficient map (C), indicating diffusion restriction. Diffusion restriction is more pronounced in the periphery of the tumor, exhibiting a targetoid pattern (arrowheads in B, C). On pathological examination, the lesion showed positive expression of keratin 19 and microvascular invasion.

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  Figure 4. Hepatocellular carcinoma showing LR-M features and non-smooth tumor margin in a 57-year-old man. An approximately 6.5 cm hepatic mass shows rim hyperenhancement in the arterial phase (A), progressive enhancement in the transitional (B), and hepatobiliary phases (C). The mass had a targetoid appearance, as the signal intensities in the arterial and hepatobiliary phases exhibited a concentric layout. Note the arterial phase peritumoral hyperenhancement, hepatobiliary phase peritumoral hypointensity, and non-smooth tumor margins. On pathological examination of the percutaneous biopsy specimen, the lesion was poorly differentiated and positive for keratin 19.

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  Figure 5. Hepatocellular carcinoma (HCC) with arterial phase peritumoral hyperenhancement and hepatobiliary phase peritumoral hypointensity in a 61-year-old man. In the arterial phase (A) and subtraction image from the pre-contrast scan (B) of gadoxetic acid-enhanced magnetic resonance imaging, arterial phase peritumoral hyperenhancement is seen (arrow) along with intratumoral hyperenhancement. In the portal venous phase (C), peritumoral hyperenhancement faded to nearly isointense to the hepatic parenchyma. In the hepatobiliary phase (D), an irregular area of peritumoral hypointensity (arrowhead) is observed. On pathological examination, the lesion was an EdmondsonSteiner grade III HCC with microvascular invasion.

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  Figure 6. Hepatocellular carcinoma (HCC) with arterial phase peritumoral hyperenhancement, hepatobiliary phase peritumoral hypointensity, and non-smooth tumor margin in a 41-year-old woman. Arterial phase peritumoral hyperenhancement is seen (arrow) along with intratumoral hyperenhancement in the arterial phase (A) of the gadoxetic acid-enhanced magnetic resonance imaging. In the hepatobiliary phase (B), an irregular area of peritumoral hypointensity was observed (arrowhead). The margin of the tumor protrudes into the hepatic parenchyma and shows a non-smooth margin. On pathological examination, the lesion was multinodular confluent, macrotrabecular-massive HCC with microvascular invasion.

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  Figure 7. Hepatocellular carcinoma with enhancing capsular appearance and hepatobiliary phase hyperintensity in a 79-year-old man. An approximately 4 cm hepatic mass shows non-rim hyperenhancement (arrow) in the arterial phase (A) and washout appearance in the portal venous phase (B) of gadoxetic acid-enhanced magnetic resonance imaging. A smooth enhancing capsule (arrowheads) on the periphery of the lesion is seen in the portal venous (B) and transitional phases (C). The entire mass is hyperintense in the hepatobiliary phase (D). Pathological examination revealed complete capsule formation and nuclear expression of β-catenin, suggesting β-catenin pathway activation.

Reference

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