Extent of portal vein tumour thrombosis in patients with hepatocellular carcinoma: The more, the worse?

Background & Aims: Portal vein tumour thrombosis (PVTT) has a significant impact on the prognosis of patients with hepatocellular carcinoma (HCC). The degree of PVTT varies from sub-/segmental invasion to complete occlusion of the main trunk. Aim of this study was to evaluate whether the degree of PVTT correlates with prognosis. Methods: A total of 1317 patients with HCC treated at our tertiary referral centre between January 2005 and December 2016 were included. PVTT was diagnosed by contrast-enhanced computed tomography or magnetic resonance imaging. The extent of PVTT was documented according to the Liver Cancer Study Group of Japan classification: Vp0 = no PVTT, Vp1 = segmental portal vein invasion, Vp2 = right anterior/posterior portal vein, Vp3 = right/left portal vein and Vp4 = main trunk. Median overall survival (OS) was calculated for each group. Results: Portal vein tumour thrombosis was present in 484 (36.8%) patients. Median OS without PVTT was 35.7 months, significantly longer than in patients with PVTT (7.2 months, P < 0.001). The patients with PVTT were subclassified as follows: 103 Vp1, 87 Vp2, 143 Vp3 and 151 Vp4. The corresponding median OS yielded 14.6, 9.4, 5.8 and 4.8 months for Vp1-Vp4, respectively (P < 0.001). Conclusions: Portal vein tumour thrombosis in patients with HCC is associated with a dismal prognosis. The results indicate an association between the extent of PVTT and OS. However, the extent of PVTT is not that decisive, as even minor PVTT leads to a very poor prognosis. Therefore, meticulous evaluation of cross-sectional imaging is crucial for the clinical management of patients with HCC.