A new classification for hepatocellular carcinoma with hepatic vein tumor thrombus

Background: Hepatic vein tumor thrombus (HVTT) is a significant poor risk factor for survival outcomes in hepatocellular carcinoma (HCC) patients. Currently, the widely used international staging systems for HCC are not refined enough to evaluate prognosis for these patients. A new classification for macroscopic HVTT was established, aiming to better predict prognosis. Methods: This study included 437 consecutive HCC patients with HVTT who underwent different treatments. Overall survival (OS) and time-dependent receiver operating characteristic (ROC) curve area analysis were used to determine the prognostic capacities of the new classification when compared with the different currently used staging systems. Results: The new HVTT classification was defined as: type I, tumor thrombosis involving hepatic vein (HV), including microvascular invasion; type II, tumor thrombosis involving the retrohepatic segment of inferior vena cava; and type III, tumor thrombosis involving the supradiaphragmatic segment of inferior vena cava. The numbers (percentages) of patients with types I, II, and III HVTT in the new classification were 146 (33.4%), 143 (32.7%), and 148 (33.9%), respectively. The 1-, 2-, and 3-year OS rates for types I to III HVTT were 79.5%, 58.6%, and 29.1%; 54.8%, 23.3%, and 13.8%; and 24.0%, 10.0%, and 2.1%, respectively. The time-dependent-ROC curve area analysis demonstrated that the predicting capacity of the new HVTT classification was significantly better than any other staging systems. Conclusions: A new HVTT classification was established to predict prognosis of HCC patients with HVTT who underwent different treatments. This classification was superior to, and it may serve as a supplement to, the commonly used staging systems.