Three categories of macroscopic growth of hepatocellular carcinoma: Nodular, mass effect, and infiltrative. Infiltrative HCC as characterized by the spread of minute tumor nodules throughout the liver. It has an aggressive course and substantially worse prognosis than nodular HCC.

On imaging, it can have an ill-defined appearance spreading over multiple hepatic segments or occupying entire lobes of the liver. The classic findings of hepatocellular carcinoma (arterial enhancement and washout on delayed phase imaging) may not be present with infiltrative tumor, likely due to alterations in normal perfusion/frequent presence of portal vein thrombosis.

In this case, large portions of the lesion have arterial enhancement and washout, and others do not, perhaps due to the lack of portal vein thrombosis. Multiple satellite lesions are also common. 

In some cases, it can be difficult to distinguish from cirrhosis due to the permeative appearance. In this case, the patient does not have gross morphologic changes of cirrhosis, although he has a history of alcohol abuse and is at risk for HCC. It is reasonable in the setting to confirm the diagnosis ultrasound-guided biopsy.