Imaging Diagnosis of Hepatocellular Carcinoma: A State-of-the-Art Review

Abstract

Hepatocellular carcinoma (HCC) remains not only a cause of a considerable part of oncologic mortality, but also a diagnostic and therapeutic challenge for healthcare systems worldwide. Early detection of the disease and consequential adequate therapy are imperative to increase patients' quality of life and survival. Imaging plays, therefore, a crucial role in the surveillance of patients at risk, the detection and diagnosis of HCC nodules, as well as in the follow-up post-treatment. The unique imaging characteristics of HCC lesions, deriving mainly from the assessment of their vascularity on contrast-enhanced computed tomography (CT), magnetic resonance (MR) or contrast-enhanced ultrasound (CEUS), allow for a more accurate, noninvasive diagnosis and staging. The role of imaging in the management of HCC has further expanded beyond the plain confirmation of a suspected diagnosis due to the introduction of ultrasound and hepatobiliary MRI contrast agents, which allow for the detection of hepatocarcinogenesis even at an early stage. Moreover, the recent technological advancements in artificial intelligence (AI) in radiology contribute an important tool for the diagnostic prediction, prognosis and evaluation of treatment response in the clinical course of the disease. This review presents current imaging modalities and their central role in the management of patients at risk and with HCC.

Keywords: artificial intelligence; computed tomography; hepatocellular carcinoma; magnetic resonance imaging; ultrasound.

Figure 1

US and CEUS surveillance examination in a patient with HBV-related cirrhosis. Baseline images detect the presence of a centimetric subcapsular hypoechoic nodule. After administration of USCA, the lesion shows arterial hyperenhancement (a) with a mild portal-venous wash-out (b).

Figure 2

Contrast-enhanced CT of the upper abdomen in the patient discussed in Figure 1. After administration of iodinated contrast agent, the subcapsular lesion showed arterial hyperenhancement (a), with progressive wash-out in the portal-venous (b) and delayed (c) phase.

Figure 3

MR examination of the patient discussed in Figure 1 and Figure 2. On T2-weighted images, the centimetric subcapsular appeared as hyperintense (a). On DWI with a b-value of 1000, the lesion showed signal restriction (b). After administration of a hepatobiliary contrast agent, the lesion showed arterial hyperenhancement (c) with hypointensity in the portal-venous phase (d) and in the hepatobiliary phase. (e) The lesion appeared hypointense.