Hepatocellular carcinoma CT
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: Mohamad Alkateb, MBBCh [2]
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Hepatocellular carcinoma Microchapters |
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Differentiating Hepatocellular carcinoma from other Diseases |
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Diagnosis |
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Treatment |
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Case Studies |
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Hepatocellular carcinoma CT On the Web |
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American Roentgen Ray Society Images of Hepatocellular carcinoma CT |
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Risk calculators and risk factors for Hepatocellular carcinoma CT |
Overview
Abdominal CT scan with intravenous contrast agent is the best method to diagnose hepatocellular carcinoma. Three-phase scanning (before contrast administration, immediately after contrast administration, and again after a delay) to increase the ability of the radiologist to detect small or subtle tumors. It is important to optimize the parameters of the CT examination, because the underlying liver disease (e.g. hepatitis B) that most hepatocellular carcinoma patients have can make the findings more difficult to appreciate.
Key CT Findings in Hepatocellular Carcinoma CT Scan
On CT, hepatocellular carcinoma (HCC) is characterized by :
- Focal HCC
- large usually hypoattenuating mass
- May have necrosis/fat/calcification
- Multifocal HCC
- Multiple masses of variable attenuation lesions
- May also have central hypoattenuating necrotic portions
- Diffuse HCC
- May be difficult to distinguish from associated cirrhosis
Enhancement pattern is the key to correct assessment of HCCs. Usually the mass enhances vividly during late arterial (~35 seconds) and then washes out, becoming indistinct or hypoattenuating in the portal venous phase, compared to the rest of the liver.
Additionally, they may be associated with a wedge shaped perfusion abnormality due to arterioportal shunts (APS), and this in turn can result in focal fatty change in the normal liver or focal fatty sparing in the diffusely fatty liver. A halo of focal fatty sparing may also be seen around an HCC in an otherwise fatty liver.