Discordance among aggressiveness characteristics of hepatocellular carcinoma: Portal vein thrombosis and multifocality, related to tumor size, but not to serum alpha-fetoprotein level.

A statistically significant association was found between PVT and MTD and between multifocality and MTD, all three of which are independent of AFP. PVT and multifocality appeared to be independent of each other. Although PVT and multifocality were independent of AFP, they were also augmented with high serum AFP levels. The results suggest the possibility of multiple pathways of tumor progression in the later stages of HCC development.