J Korean Soc Radiol.  2019 May;80(3):374-393. 10.3348/jksr.2019.80.3.374.

A Comprehensive Review of Hepatocellular Carcinoma Enhancement Patterns in MRI: Emphasis on Gadoxetate-Enhanced Imaging

• Kim SS
• Choi JY
• Rhee H

• KMID: 2454021
• DOI: http://doi.org/10.3348/jksr.2019.80.3.374

Abstract

In patients at high risk of hepatocellular carcinoma (HCC), such as those with chronic hepatitis or cirrhosis, the confirmative diagnosis of HCC can be made solely from characteristic imaging findings on contrast-enhanced CT or MR scans. However, in daily practice, HCCs showing atypical imaging features are frequently encountered. Since the criteria for diagnosis of HCC is based on dynamic contrast enhancement patterns, it is essential to thoroughly understand these patterns. In this article, we aim to use gadoxetate-enhanced MRI to comprehensively review the HCC enhancement patterns and the associated histopathologic findings with their prognostic factors.

MeSH Terms

Carcinoma, Hepatocellular*
Diagnosis
Fibrosis
Hepatitis, Chronic
Humans
Magnetic Resonance Imaging*
Tomography, X-Ray Computed

Figure

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  Fig. 1 Hepatocellular carcinoma without “washout” enhancement patterns, but showing transitional hypointensity. Hepatocellular carcinoma with Edmonson-Steiner grade I–II was confirmed via surgery. A, B. A 57-year-old male patient with non-alcoholic fatty liver disease underwent MRI using the extracellular contrast agent (gadoterate meglumine; Dotarem, Guerbet, France). The signal intensity of the focal hepatic lesion in the left lateral section is more than that of the adjacent liver parenchyma in both the portal (A, arrow) and the delayed phases (B, arrow). The lesion showed nonrim hyperenhancement in the late arterial phase (not shown). C, D. After 21 days, the same patient underwent MRI using the hepatocyte-specific contrast agent (gadoxetate; Primovist, Bayer Healthcare, Berlin, Germany). The signal intensity of the focal hepatic lesion in the left lateral section is similar to that of the adjacent liver parenchyma in the portal phase (C, arrow). However, in the transitional phase (D, arrow), the signal intensity of the lesion is less than that of the adjacent liver parenchyma. The lesion showed nonrim hyperenhancement in the late arterial phase (not shown).

• 

  Fig. 2 Early hepatocellular carcinoma without arterial hyperenhancement, but showing hypointensity in the hepatobiliary phase. A 57-year-old male patient with liver cirrhosis underwent MRI using the hepatocyte-specific contrast agent (gadoxetate). Early hepatocellular carcinoma was confirmed via surgery. A. The focal hepatic lesion in the right hemiliver is not clearly delineated due to the absence of arterial hyperenhancement in the late arterial phase (arrow). B. In the portal phase, the signal intensity of the lesion is less than that of the adjacent liver parenchyma (arrow). C. In the hepatobiliary phase, the lesion shows hypointensity (arrow).

• 

  Fig. 3 Dysplastic nodule showing hypointensity in the hepatobiliary phase. A 61-year-old male patient with hepatitis B-related cirrhosis underwent MRI using the hepatocyte-specific contrast agent (gadoxetate). The high-grade dysplastic nodule was confirmed via surgery. A. In the precontrast T1-weighted image, the focal hepatic lesion in the right hemiliver shows hyperintensity (arrow). B. In the arterial phase with the subtraction technique, the lesion shows no arterial hyperenhancement (arrow). C. In the portal phase, the lesion shows isointensity with the adjacent liver parenchyma (arrow). D. In the hepatobiliary phase, the lesion shows hypointensity (arrow).

• 

  Fig. 4 Poorly differentiated hepatocellular carcinoma without arterial hyperenhancement. A 61-year-old female patient with hepatitis B-related cirrhosis underwent MRI using the hepatocyte-specific contrast agent (gadoxetate). The poorly differentiated hepatocellular carcinoma was confirmed through surgery. The hematoxylin-eosin staining slide displayed a large area of central necrosis (not shown). A. The focal hepatic lesion in the left lateral section shows no arterial hyperenhancement in the late arterial phase. B. In the portal phase, the signal intensity of the lesion is less than that of the adjacent liver parenchyma. The central portion of the lesion showed no contrast enhancement throughout the entirety of the dynamic sequences (not shown). C. In the hepatobiliary phase, the lesion shows hypointensity.

• 

  Fig. 5 Scirrhous hepatocellular carcinoma without “washout” enhancement patterns. A 47-year-old male patient with hepatitis B-related cirrhosis underwent MRI using the hepatocyte-specific contrast agent (gadoxetate). Scirrhous hepatocellular carcinoma was confirmed via surgery. A. The focal hepatic lesion in the right hemiliver shows arterial hyperenhancement in the late arterial phase (arrow). B, C. In the portal (B, arrow) and transitional (C, arrow) phases, contrast enhancement is persistent without “washout.” D. In the hepatobiliary phase, the lesion shows a targetoid appearance from the contrast retention at the central area (arrow).

• 

  Fig. 6 Hepatocellular carcinoma showing irregular rim enhancement. A 61-year-old male patient with chronic B-viral hepatitis underwent MRI using the hepatocyte-specific contrast agent (gadoxetate). Hepatocellular carcinoma was confirmed via surgery. The hematoxylin-eosin staining slide displayed a large area of central necrosis (not shown). A. The focal hepatic lesion in the right hemiliver shows irregular rim enhancement in the late arterial phase (arrow). B. In the transitional phase, the lesion shows persistent irregular rim enhancement (arrow). The central portion of the lesion showed no contrast enhancement throughout the entirety of the dynamic sequences (not shown).

• 

  Fig. 7 Hepatocellular carcinoma with microvascular invasion. A 58-year-old male patient with chronic B-viral hepatitis underwent MRI using the hepatocyte-specific contrast agent (gadoxetate). Hepatocellular carcinoma with microvascular invasion and infiltrative tumor margin was confirmed via surgery. A. The focal hepatic lesion is seen in the left medial section. In the late arterial phase, the lesion shows nonrim arterial hyperenhancement. Irregular enhancement is also seen in the peritumoral liver parenchyma. B. In the hepatobiliary phase, the lesion shows hypointensity and a non-smooth margin. The peritumoral liver parenchyma also shows hypointensity.

• 

  Fig. 8 Hepatocellular carcinoma showing intratumoral vessels with aneurysmal change. A 47-year-old male patient with chronic B-viral hepatitis underwent MRI using the hepatocyte-specific contrast agent (gadoxetate). A large mass is seen in the right hemiliver. Strongly enhancing vessels are seen inside the tumor in the late arterial phase, some of which accompany aneurysmal change (arrow). Poorly differentiated hepatocellular carcinoma was confirmed via surgery. The hematoxylin-eosin staining slide demonstrated a large area of central necrosis and multiple intratumoral vessels with a pseudoaneurysmal change (not shown).

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  Fig. 9 Hepatocellular carcinoma showing hyperintensity in the hepatobiliary phase. A 73-year-old male patient with chronic B-viral hepatitis underwent MRI using the hepatocyte-specific contrast agent (gadoxetate). The focal hepatic lesion in the left lateral section shows homogeneous hyperintensity in the hepatobiliary phase (arrow). The lesion showed arterial hyperenhancement and no “washout” or transitional hypointensity in the dynamic sequences (not shown). Moderately differentiated hepatocellular carcinoma was confirmed via surgery. Expression level of the organic anion transporting polypeptide 8 was higher in the tumor than in the adjacent liver parenchyma (not shown). The tumor did not recur for over five years after the surgery.

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