Category:Liver, Primary Tumours

Primary tumours are not as common as secondary tumours. They may arise from each of the four main tissues within the liver, liver parenchymal cells (hepatoma, liver cell carcinoma), bile ducts (cholangioma, bile duct carcinoma), blood vessels (haemangioma, haemangiosarcoma), connective tissue (fibroma, sarcoma). NB: Liver cell tumours and malignant bile duct tumours are the two most common primary hepatic neoplasms. Liver cell tumours are usually seen as discrete masses within the liver parenchyma. The tumour tissue is usually reddish brown in colour. It can be malignant, metastases occuring to the local lymph nodes and lungs.

Adenoma

Carcinoma

Hepatocytic

• more in dogs and cats

Gross

• can be difficult to distinguish grossly from adenomas
• usually one single large mass and additional smaller masses (intrahepatic metastases)
• may have features of malignancy such as internal necrosis and haemorrhage

Microscopically

• can be very variable appearing as sheets or cords of neoplastic cells
• cells generally smaller with a higher nucleus to cytoplasmic ratio

Cholangiocellular - bile duct

Adenoma

Haemangiosarcoma

Cholangiocellular - bile duct

• can be primary in the liver
• other predilection sites
  • spleen
  • right auricle of the heart
• prevalent in large breeds