Will the collaboration of surgery and external radiotherapy open new avenues for hepatocellular carcinoma with portal vein thrombosis?

Figure 2 Illustration of two systems categorizing portal vein thrombus. A: Invasion of the second-order branch of the portal vein: VP2 in the liver cancer study group of Japan (e.g., Vp1 denotes the invasion distal to the second-order branch) and Cheng’s classification type I; B: Invasion of the first-order branch: VP3 and Cheng’s type II; C: Invasion of the main branch and/or bilateral first-order branches: VP4 and Cheng’s type III; D: Invasion of the superior mesenteric vein: Cheng’s type IV.