Benign Liver Lesions

Question 1

Haemangioma

Answer 1

Most common benign tumours of mesenchymal origin
Incidence in autopsy series is 8%
Cavernous haemangiomas may be enormous
Clinically they are reddish purple hypervascular lesions
Lesions are normally separated from normal liver by ring of fibrous tissue
On ultrasound they are typically hyperechoic

Question 2

Liver cell adenoma

Answer 2

90% develop in women in their third to fifth decade
Linked to use of oral contraceptive pill
Lesions are usually solitary
They are usually sharply demarcated from normal liver although they usually lack a fibrous capsule
On ultrasound the appearances are of mixed echoity and heterogeneous texture. On CT most lesions are hypodense when imaged prior to administration of IV contrast agents
In patients with haemorrhage or symptoms removal of the adenoma may be required

Question 3

Mesenchymal hamartomas

Answer 3

Congential and benign, usually present in infants. May compress normal liver

Question 4

Liver abscess

Answer 4

Biliary sepsis is a major predisposing factor
Structures drained by the portal venous system form the second largest source
Common symptoms include fever, right upper quadrant pain. Jaundice may be seen in 50%
Ultrasound will usually show a fluid filled cavity, hyperechoic walls may be seen in chronic abscesses

Question 5

Amoebic abscess

Answer 5

Liver abscess is the most common extra intestinal manifestation of amoebiasis
Between 75 and 90% lesions occur in the right lobe
Presenting complaints typically include fever and right upper quadrant pain
Ultrasonography will usually show a fluid filled structure with poorly defined boundaries
Aspiration yield sterile odourless fluid which has an anchovy paste consistency
Treatment is with metronidazole

Question 6

Hyatid cysts

Answer 6

Seen in cases of Echinococcus infection
Typically an intense fibrotic reaction occurs around sites of infection
The cyst has no epithelial lining
Cysts are commonly unilocular and may grow to 20cm in size. The cyst wall is thick and has an external laminated hilar membrane and an internal enucleated germinal layer
Typically presents with malaise and right upper quadrant pain. Secondary bacterial infection occurs in 10%.
Liver function tests are usually abnormal and eosinophilia is present in 33% cases
Ultrasound may show septa and hyatid sand or daughter cysts.
Percutaneous aspiration was previously contra indicated, it is not incorporated into some treatment regimens
Treatment is by sterilisation of the cyst with mebendazole and may be followed by surgical resection. Hypertonic swabs are packed around the cysts during surgery

Question 7

Polycystic liver disease

Answer 7

Usually occurs in association with polycystic kidney disease
Autosomal dominant disorder
Symptoms may occur as a result of capsular stretch

Question 8

Cystadenoma

Answer 8

Rare lesions with malignant potential
Usually solitary multiloculated lesions
Liver function tests usually normal
Ultrasonography typically shows a large anechoic, fluid filled area with irregular margins. Internal echos may result from septa
Surgical resection is indicated in all cases