Simple liver cysts — fluid-filled cavities in the liver — usually cause no signs or symptoms and need no treatment. However, they may enlarge enough to cause pain or discomfort in the upper right part of the abdomen.

What is it?

Simple liver cysts — fluid-filled cavities in the liver — usually cause no signs or symptoms and need no treatment. However, they may enlarge enough to cause pain or discomfort in the upper right part of the abdomen. Simple liver cysts are always benign. The only patients who require treatment for liver cysts are those who develop symptoms. Larger cysts may occasionally cause some dull pain and/or swelling in the upper right hand side of the abdomen. Jaundice , which is often caused by bile duct obstruction, is rare. Liver cysts do not impair the liver's ability to function.

Most liver cysts can be detected on ultrasound or computerized tomography (CT) scans. When needed, treatment may include drainage or removal of the cyst.

The cause of simple liver cysts isn't known, but they may be present at birth (congenital). Rarely, liver cysts may indicate a serious, underlying condition such as:

  • Polycystic liver disease, an inherited disorder
  • Echinococcus infection, a parasitic infection
  • Liver cancer

If required, to reduce their size, fluid can be removed from the cyst by inserting a needle through the skin under X-ray guidance and withdrawing (aspirating) the fluid. To prevent the fluid refilling the cyst a substance called sclerosant is injected into the cyst to help keep the walls of the cyst together.

Symptoms

In most cases, simple liver cysts do not causes any symptoms, however some patients can experience:

  • Upper abdominal fullness
  • Discomfort
  • Pain

What causes it?

Simple cysts arise from a malformation of your bile ducts. These cysts are thought to be congenital (present from birth) but they are not inherited and are unrelated to polycystic liver disease in which many more cysts are present. 

References

http://my.clevelandclinic.org/health/diseases_conditions/liver-disease/liver_cysts_tumors

http://emedicine.medscape.com/article/190818-overview

http://www.britishlivertrust.org.uk/liver-information/liver-conditions/benign-tumours-and-cystic-disease/