• liver;
  • anatomy;
  • cynomolgus monkey


No detailed description of nonhuman primate liver anatomy has been reported and little is known about the similarity between such livers and human liver. The cynomolgus monkey (Macaca fascicularis) was used to establish a preclinical model of genetically modified hepatocytes auto transplantation. Here, we report information gleaned from careful observation and notes obtained from 59 female cynomolgus monkeys undergoing 44 anatomical hepatic resections, 12 main portal vein division dissections and selective branch ligations, and 46 portographies. Additionally, three anatomical liver dissections after total resection at autopsy were performed and served to confirm peroperative observations and for photography to provide illustrations. Our results indicate that the cynomolgus monkey liver has four lobes: the median (the largest), the right and left lateral, and the caudate lobes. In 60% (N=20) of individuals the portal bifurcates into right and left portal veins, in the remaining 40% (N=14) the portal vein trifurcates into right anterior, right posterior, and left portal veins. The anatomy and branching pattern of the hepatic artery and bile ducts closely follow those of the portal branches. Functionally, the cynomolgus monkey liver can be divided into eight independent segments. Thus, we report the first detailed description of the hepatic and portal surgical anatomy of the cynomolgus monkey. The cynomolgus monkey liver is more similar to the human liver than are livers of any small or large nonprimate mammals that have been described. Am. J. Primatol. 71:400–408, 2009. © 2009 Wiley-Liss, Inc.