GPC3 and hepatocellular carcinoma: Circulating tumor cell (CTC) research in HCC has focused on peripheral blood samples and epithelial cellular adhesion molecule (EpCAM)-based detection, which may not fully capture the tumor biology of portal venous dissemination.2 Previously, the authors developed a method for detecting glypican-3 (GPC3)-positive CTCs and demonstrated its clinical utility.3 However, its prognostic and predictive value in portal venous blood remains unclear.