Cyst in the liver is one of the most common liver conditions. Fortunately, most are simple cysts and benign thus no treatment is required. On the other hand, some cysts are complex and/or can cause symptoms, then further investigations and treatment may be necessary.
What are liver cysts?
Liver cysts are sacs filled with fluid in the liver. In most cases, liver cysts are found by incidentally on ultrasound (US) or computed tomography (CT) scans during a health check or as part of other evaluations.
Simple liver cysts most commonly refer to non-parasitic, non-neoplastic (non-tumour) cysts of the liver. They may occur as a single cyst, or as a small number of cysts scattered in different parts of the liver. When they are multiple, they may represent a syndrome known as polycystic liver disease.
Most simple liver cysts have no symptoms. They are usually small and benign. However, they may increase in size over time and cause symptoms.
Rarely, they can become infected or bleed within and cause pain or fever.
These symptoms may include:
- Dull aching pain over the upper abdominal area
- Feeling of bloatedness or fullness
- Patient may actually feel a lump over the liver in the upper abdomen
- Severe pain may indicate infection of the cyst, bleeding or rupture of the cyst.
Occasionally, the cyst may be classified as complex. In such cases, further investigations may be required to evaluate the risk of it turning cancerous or harbouring a cancer.
Simple liver cysts should be treated only when they are symptomatic. Asymptomatic cysts can be left alone as complications arising from such cysts such as infection or bleeding are rare.
The risk of asymptomatic simple cysts getting bigger and eventually causing symptoms is low. Hence there is no need for long-term follow-up of cysts that have been confidently diagnosed as simple liver cysts.
The optimal treatment of symptomatic cyst is to partially remove the wall of the cyst to allow drainage of the cyst into the abdominal cavity. This is now performed mostly through laparoscopic (keyhole) surgery and recovery is fast. The chance of recurrence of cysts treated surgically is low.
Aspiration of the cyst contents, even when combined with alcohol ablation of the cyst wall has high recurrence rate and is generally not recommended.
For complex or high-risk cyst, surgery may be recommended to exclude cancer, removal of the whole cyst with a margin of normal liver may be necessary. These can also be done via minimally-invasive approaches (laparoscopic or robotic), minimising pain and improving recovery.