Pathology of malignant liver tumours

Neoplasms of the liver may arise from any cell type within the liver parenc hyma. Hepatocellular carcinoma is by far the most common primary malignant tumour of the liver in adults. Indeed, it is one of the most common tumours in the world with striking geographic differences. These incidence rates c an be explained by differences in Hepatitis-Virus carrier rates which they closely reflect. Nearly 10 % of malignant liver tumors are represented by c holangiocarcinoma which originates from small intrahepatic bile ducts. Hepa toblastoma accounts for approximately 5 % of malignancies in childhood. Mos t hepatoblastomas fall into epithelial or mixed epithelial and mesenchymal categories. Fetal-type cells and embryonal-type cells represent the epithel ial components. Rare primary malignant non-epithelial tumours are angiosarc omas, leiomyosarcomas or fibrosarcomas, arising from vascular or mesenchyma l components of the liver respectively. All types of Hodgkin and Non-Hodgki n Lymphomas may secondarily involve the liver. Most primary hepatic lymphom as are of diffuse large B-cell type and are extremely rare.