Abstract
Hepatocellular carcinoma (HCC) is one of the few cancers with a 5-year survival that has remained below 20%; however, prognosis differs by tumor stage at diagnosis. Curative treatment options among patients with early-stage HCC afford a median survival of 5-10 years. Accordingly, international society guidelines recommend semi-annual HCC surveillance in at-risk patients, including those with cirrhosis or high-risk chronic hepatitis B infection. Surveillance is associated with increased early-stage HCC detection and curative treatments, leading to reduced HCC-related mortality. Abdominal ultrasound has been the cornerstone for HCC surveillance for the past two decades, but recent data have highlighted its suboptimal sensitivity for early-stage HCC detection, particularly in patients with obesity and those with non-viral etiologies of liver disease. The combination of ultrasound plus alpha fetoprotein (AFP) has higher sensitivity for early-stage HCC detection than ultrasound alone, although the combination still misses over one-third of HCC at an early stage. Emerging imaging and blood-based biomarker strategies have promising data in biomarker phase 2 (case-control) and phase 3 (cohort) studies. Beyond ultrasound, Magnetic resonance imaging (MRI) is the best-studied imaging strategy, with superior sensitivity and specificity compared to ultrasound in a cohort study. Abbreviated MRI protocols have been proposed to address concerns about MRI radiological capacity, costs, and patient acceptance. Of biomarker strategies, GALAD (a panel including gender, age, AFP, AFP-L3, and DCP) is the best validated, with promising sensitivity for early-stage HCC detection in a national multi-center cohort study. Liquid biopsy biomarkers, including methylated DNA markers, have also shown promising accuracy in case-control studies. Abbreviated MRI and GALAD are now entering prospective trials that examine clinical outcomes such as early-stage HCC detection and screening-related harms, which are essential data to understand for adoption in clinical practice. As additional surveillance strategies become available, it will allow an era of precision surveillance in which optimal surveillance modalities are tailored to individual patient risk and expected test performance.