Tumours of the Liver

Tumours of the Liver

·        Metastases are the most common

Hepatocellular carcinoma

·        Epidemiology:

o  80% of all liver primary cancer

o  Third world: 40% of all cancer, age 20 – 40

o  Western world: age 60+

·        Pathogenesis:

o   Hepatitis B: Commonest where carrier state begins in infancy. Viral DNA integrates into the genome

o   Cirrhosis: chronic regenerative activity

o   Fungal toxins: aflatoxin, mycotoxin

·        Macroscopic appearance: Either large, unifocal mass, multifocal widely distributed nodules, or infiltrative cancer. Yellow-white masses, occasionally bile stained

·        Microscopic appearance:

o   Well differentiated: Trabeculae and acini of malignant cells, large irregular nuclei, bile pigment, cytoplasmic inclusions

o   Anaplastic: giant cell, small cell, spindle cell

o   Fibrolamellar carcinoma (important variant): Single mass with fibrous bands, well-differentiated cells. No cirrhotic background. In kids/young adults. Better prognosis

Cholangiocarcinoma

·        Arises in intrahepatic biliary tree

·        Associated with parasitic infestation (ie 3^rd world)

·        Microscopic appearance: well to poorly differentiated adenocarcinoma. Malignant ductules in a dense stroma 

·        Clinical: ill defined upper abdo pain, malaise, fatigue, enlarged nodular liver, poor prognosis due to late presentation

Rarer Cancers

·        Angiosarcoma: malignant tumour of blood vessels. Haemorrhagic appearance in liver. Associated with vinyl chloride (ie plastics manufacture) and arsenic

·        Hepatoblastoma: In infants, can be epithelial or mixed, recapitulates foetal liver

Benign Tumours of the Liver

·        Bile duct adenoma: “von Myenberg complex”, 1 cm pale nodules composed of small ducts in fibrous tissue. Incidental finding at surgery

·        Liver cell adenoma:

o   Associated with oral contraceptives, pregnancy, anabolic steroids. Rupture can lead to massive haemorrhage (eg in pregnancy).

o   Appearance: soft-yellow bile stained well-circumscribed nodules. Sheets and cords of polygonal cells, lack normal architecture. No features of malignancy (although mildly pleomorphic)

·        Other: Cavernous haemangioma, biliary cysts, focal nodular hyperplasia