[1] Liver Cysts Flashcards
Are cystic diseases of the liver common?
Relatively
How are cystic diseases of the liver most commonly identified?
Incidentally on routine imaging
Are cystic diseases of the liver serious?
In rare cases they can be complicated and life-threatening
What are simple liver cysts?
Simple, fluid-filled epithelial-lined sacs within the liver
Where do simple liver cysts most commonly occur?
In the right lobe
What is the prevalence of simple liver cysts?
2.5-18%
What happens to the incidence of simple liver cysts with age?
Increases
What are simple liver cysts due to?
Thought to be due to congenitally malformed bile ducts, failing to connect the extrahepatic ducts
What does the failure of hepatic bile ducts to connect with extrahepatic ducts lead to?
Local dilation filled with bile-like fluid
How are most simple liver cysts found?
Incidentally on imaging
What % of patients with simple liver cysts experience symptoms
10-15%
What symptoms may be produced by simple liver cysts?
Abdominal pain
Nausea
Early satiety
What typically causes the symptoms of simple liver cysts?
Mass effect on the surrounding structures
Is there a correlation between increased size of simple liver cysts and increased incidence of complications?
Yes, there seems to be
What investigations are done in suspected simple liver cysts?
Bloods
Ultrasound
What may be found on bloods in simple liver cysts?
LFTs are typically normal, although a small number of patients may have raised GGT
Tumour markers CEA and CA19-9 may be elevated
How do simple liver cysts appear on ultrasound?
They are characteristically anechoic, well-defined, thin-walled (often imperceptible), oval/spherical lesions with no septations, and strong posterior wall acoustic enhancement
Do simple liver cysts require intervention?
Most require no intervention
What is recommended for simple liver cysts ?>4cm in size?
Follow-up ultrasound scans at 3, 6, and 12 months post-detection to check for growth
What is done if the size of simple liver cysts remains unchanged after 2-3 years of ultrasound follow up?
No further scans are required unless the patient becomes symptomatic
When may further intervention be warranted in simple liver cysts?
If the patient is symptomatic or the diagnosis is uncertain
What are the options for intervention in simple liver cysts?
Ultrasound-guided aspiration
Laparoscopic de-roofing
What is characteristic of simple liver cysts on laparoscopy?
A ‘blue hue’
What is the advantage of laparoscopy over aspiration in the management of simple liver cysts?
Has lower rates of failure and recurrence
What is polycystic liver disease characterised by?
The presence of 20 or more cysts within the liver parenchyma, each of which are 1cm or more in size
What is polycystic liver disease caused by?
Autosomal dominant polycystic kidney disease or autosomal dominant polycystic liver disease
What is autosomal dominant polycystic kidney disease caused by?
Mutations in the PKD1 and PKD2 genes
Where is the PKD1 gene found?
Chromosome 16
Where is the PKD2 gene found?
Chromosome 4
What % of patients with autosomal dominant polycystic kidney disease will also develop liver cysts?
10-60%
What causes autosomal dominant polycystic liver disease?
Mutations in the PRKCSH or SEC63 genes
Where is the PRKCSH gene found?
Chromosome 19
Where is the SEC63 gene found?
Chromosome 6
Will patients with autosomal dominant polycystic liver disease have renal involvement?
No
How do the mutations in the genes causing autosomal dominant polycystic liver and kidney disease cause liver cysts?
They result in aberrant ductal plate configurations during liver embryogenesis, which are not connected to the intrahepatic bile ducts and so do not drain, leading to dilation and eventual cyst formation as they progressively fill with bile-like fluid
Is polycystic liver disease symptomatic?
The majority of patients are asymptomatic
What may symptoms result from in polycystic liver disease?
Localised compression or complications
How do patients with symptomatic polycystic liver disease present?
Abdominal pain present as the cysts grow in size, and hepatomegaly being present on examination
How might concurrent renal disease present in polycystic liver disease?
Additional urinary tract symptoms
What will significant disease eventually cause in polycystic liver disease?
Liver cirrhosis and portal hypertension
What may bloods show in polycystic liver disease?
Patient will have normal LFTs (ALP can become raised in a small proportion)
Renal function may be affected in those who also have renal cysts
How is a definitive diagnosis of polycystic liver disease made?
Ultrasound imaging
What is found on ultrasound imaging in polycystic liver disease?
Multiple cysts, usually 20 or more, which have the same sonographic characteristics as simple cysts
How can asymptomatic polycystic liver disease be managed?
Patients can be left alone and monitored
Will patients with asymptomatic polycystic liver disease eventually need some form of intervention?
Many patients will, due to the progressive nature of the disease
What medical management may be of use in polycystic liver disease?
Some trials have demonstrated the short-term benefit for somatostatin analogues in symptomatic relief
How do somatostatin analogues work in providing symptomatic relief for polycystic liver disease?
They reduce cyst volume
What are the indications for surgery for cystic liver lesions?
Intractable symptoms
Inability to rule out malignancy on imaging alone
Prevention of malignancy
What are the surgical options for the treatment of polycystic liver disease?
US-guided aspiration
Laparoscopic de-roofing of cysts
What is the use of US-guided aspiration in polycystic liver disease?
May provide temporary relief in patients experiencing pain due to cyst size
Why is US-guided aspiration not used routinely in polycystic liver disease?
Due to fluid re-accumulation
Where is laparoscopic de-roofing of cysts the preferred technique in polycystic liver disease?
In those experiencing symptoms, or for those whom there is evidence of compression of surrounding structures
What treatment option can be employed where particular liver segments are grossly affected by polycystic liver disease?
Resection
What treatment options may be warranted in extreme cases of polycystic liver disease?
Transplantation
What % of liver cysts are true cystic neoplasms of the liver?
<5%
What is the most common subtype of cystic neoplasms of the liver?
Cystadenoma
What are cystadenomas?
Non-invasive mucinous cystic neoplasms
Are cystadenomas malignant?
No, they are pre-malignant lesions
What causes the development of cystadenomas?
Abnormal proliferation of the biliary epithelium
What can cystadenomas transform into?
Can undergo malignant transformation into cystadenocarcinomas in around 10% cases
Are cystic neoplasms of the liver always symptomatic?
No, patients are commonly asymptomatic
What is the rate of growth of cystic neoplasms of the liver?
Slow, typically 1-2mm per year
What is the result of the slow growth of cystic neoplasms of the liver?
Symptoms may develop insidiously
What are the common symptoms of cystic neoplasms of the liver in symptomatic individuals?
Abdominal pain Anorexia Nausea Fullness Bloating
What may the blood shows in cystic neoplasms of the liver?
LFTs are often normal, although ALP, CEA< and CA19-9 can become mildly elevated
What can be used to differentiate between simple cysts and more complicated cystic lesions in the liver?
Ultrasound scanning
What should be performed on all patients in whom a cystic neoplasm is suspected?
CT imaging with contrast
Why should CT imaging with contrast be performed on all patients with suspected cystic neoplasms?
For further delineation and to check for evidence of metastasis
Why should aspiration or biopsy be avoided if a cystic neoplasm is suspected?
It can result in potential peritoneal seeding of the malignancy
What features can be seen on imaging for liver cysts that are suspicious for malignancy?
Septations
Wall enhancement
Nodularity
What features can be seen on imaging for liver cysts that are suspicious for an abscess?
Debris within the lesions
Loculation
What features can be seen on imaging that are suspicious for hydatid cysts?
Calcification
‘Daughter cysts’ around the main lesion
What is the treatment of choice for cystadenomas and cystadenocarcinomas?
Liver lobe resection
What happens following liver lobe resection in cystadenomas and cystadenocarcinomas?
They are sent for histopathology to confirm the diagnosis
What does a hydatid cyst result from?
Infection with the tapeworm Echinococcus granulosus
How is Echinococcus granulosus transmitted?
The eggs are passed by faeco-oral transmission
What excretes the Echinococcus granulosus larvae?
Carnivores, commonly dogs
What happens once the Echinococcus granulosus larve have entered the hosts GI tract?
They pass into the hepatic portal system into the liver, where they continue to grow and form cysts
Where is echinococcal disease found?
Has a global distribution, though the highest prevalence is in South America, North Africa and Central Asia
How quickly can hydatid cysts grow?
Many only grow at a rate of a couple of mm’s a year
What is the result of hydatid cysts only growing at a rate of a couple of mm’s per year?
They can remain asymptomatic and undetected for many years
What is the most common presenting symptom of hydatid cysts?
Vague abdominal pain
What causes the abdominal pain in hydatid cysts?
Mass effect on the surrounding structures, or due to rupture
What presentations can hydatid cysts result in?
Jaundice Cholangitis Vomiting Dyspepsia Early satiety Anaphylaxis
When can hydatid cysts cause cholangitis?
If the biliary system is involved
When can hydatid cysts cause anaphylaxis?
If the cyst ruptures into the thorax or intraperitoneally
What may be found on bloods in a hydatid cyst?
LFTs are often abnormal, unless presenting with cholangitis picture
FBC can show eosinophilia
What % of those with hydatid cysts have positive Echinococcal antibody titres?
80%
What will be shown on ultrasound scanning with hydatid cysts?
Calcified, spherical lesion with multiple septations
May be anechoic or containing snowflake-like inclusions
How can further imaging assessment of a hydatid cyst be performed?
CT imaging with contrast
Why is aspiration not recommended in those with suspeted hydatid cysts?
It may rupture, which can cause an anaphylactic reaction
How can hydatid cysts be managed if they are asymptomatic and inactive?
May be possible to monitor them
What is the primary treatment for hydatid cysts?
Surgical cyst deroofing
What are the options for the surgical management of hydatid cysts in specialist centres?
Radiological agents and injection of a scolecidal agent
What is the use of medical management in hydatid cysts?
It is used as an adjunct to surgical therapy
Who is medical management of hydatid cysts used for?
Those with widely disseminated hydatid disease, or in patients who are unfit for surgery
What is given to patients with hydatid cysts whom are in need of active treatment?
Anti-microbial action varies, however a combination of albendazole, mebendazole, and/or praziquantel is normally given