Noninvasive imaging of hepatocellular carcinoma: From diagnosis to prognosis

Abstract

Hepatocellular carcinoma (HCC) is the most common primary liver cancer and a major public health problem worldwide. Hepatocarcinogenesis is a complex multistep process at molecular, cellular, and histologic levels with key alterations that can be revealed by noninvasive imaging modalities. Therefore, imaging techniques play pivotal roles in the detection, characterization, staging, surveillance, and prognosis evaluation of HCC. Currently, ultrasound is the first-line imaging modality for screening and surveillance purposes. While based on conclusive enhancement patterns comprising arterial phase hyperenhancement and portal venous and/or delayed phase wash-out, contrast enhanced dynamic computed tomography and magnetic resonance imaging (MRI) are the diagnostic tools for HCC without requirements for histopathologic confirmation. Functional MRI techniques, including diffusion-weighted imaging, MRI with hepatobiliary contrast agents, perfusion imaging, and magnetic resonance elastography, show promise in providing further important information regarding tumor biological behaviors. In addition, evaluation of tumor imaging characteristics, including nodule size, margin, number, vascular invasion, and growth patterns, allows preoperative prediction of tumor microvascular invasion and patient prognosis. Therefore, the aim of this article is to review the current state-of-the-art and recent advances in the comprehensive noninvasive imaging evaluation of HCC. We also provide the basic key concepts of HCC development and an overview of the current practice guidelines.

Keywords: Magnetic resonance imaging; Surveillance; Computed tomography; Staging; Ultrasound; Guidelines; Diagnosis; Hepatocellular carcinoma; Prognosis

Core tip: Noninvasive imaging modalities allow diagnosis, characterization, staging, surveillance, and prognosis evaluation of hepatocellular carcinoma (HCC). Functional magnetic resonance imaging techniques show promise in providing further important information of tumor biological behaviors, and, thus, improve the early detection ability and characterization accuracies for HCC. Development of prediction model comprising serological, imaging, texture, and radiogenomic parameters may facilitate preoperative evaluation of tumor recurrence and patient survival. Here, we reviewed recent advances in imaging techniques for noninvasive HCC assessment, basic key concepts of HCC development, and current practice guidelines for HCC management.