The portal vein, or hepatic portal vein, is the main blood vessel of the portal venous system (PVS), which delivers blood to the liver from the stomach, intestines, spleen, gallbladder, and pancreas.

Non-anatomical resections were defined as resections ignoring segmental anatomy of the liver ... according to the vessels invaded (i.e. portal vein, hepatic artery, hepatic vein, and bile duct).