Liver cysts also known as hepatic cysts are fluid filled cavity with a presence of epithelial lining. Liver cysts can be classified as true or false cysts depending on the presence of epithelial lining. True cysts consist of congenital cysts such as simple cysts and polycystic liver disease, parasitic cysts such as Echinococcosis (caused by either Echinococcus granulosis or Echinococcus multilocularis), neoplastic cysts such as cystadenoma, cystadenocarcinoma, cystic sarcoma, squamus cell carcinoma and metastatic cancers from ovaries, colon, kidneys and pancreas and biliary duct related cysts such as Caroli disease, bile duct duplication and peribiliary cysts. False liver cysts are an impact of intrahepatic hemorrhage, post traumatic hematoma or intrahepatic biloma.
Simple non-parasitic hepatic cysts are a result of congenital aberration of bile duct cells and thought to be triggered by chromosome 16. They are filled with bile like fluid and the lining of the cyst is made of bile duct epithelium, so it is hypothesized that they are formed during embryogenesis. Generally, they are solitary cysts, but can also present as multiple simple cysts having more than one cyst at a time, even in the absence of polycystic liver disease. Multiple simple cysts can be classified into type 1 that consists of few large cysts (about 7-10 cm in size), type 2 that consists of multiple medium cysts (about 5-7 cm in size) and type 3 that consist of diffuse small to medium cysts (less than 5 cm in size).
Clinical Presentation of Liver Cysts
Simple liver cysts are the most common type of hepatic cysts that are found in about 2.5-18% of individuals. Their prevalence increases with age having female predominance that is more common in 40-60 age groups. They have an etiological relation to female sex hormone (estrogen), as their predominance increases after pregnancy, exposure to oral contraceptive pills and postmenopausal women on hormone replacement therapy. Generally, most of the cysts are small and asymptomatic, but some individuals in whom the cysts are large can present with symptoms of abdominal discomfort, distension, early satiety, nausea, vomiting and back discomfort. Although, complications are rare, portal hypertension, obstructive jaundice, hemorrhage, rupture and biliary obstruction can be found in large cysts.
Can Liver Cysts Go Away On their Own?
Simple asymptomatic cysts, in most cases, require no treatment and they can regress spontaneously. Yes, liver cysts do go away on their own, especially if their size ranges from 2-4 cm. However, larger liver cysts measuring above 4 cm do not go away on their own. Some may remain stable in size while others may grow in size, therefore, if one is diagnosed with a liver cyst, regular monitoring is required. Although, symptomatic cysts are not life threatening; however, they can significantly affect a patient’s quality of life if they continue to grow in size and complications such as infection, hemorrhage or rupture may develop.
What Is The Management Of Cysts That Do Not Go Away On Their Own?
Cysts that do not go away on their own and are symptomatic need to be managed properly to relieve symptoms and to improve quality of life of the patient. The treatment measures include percutaneous needle aspiration with or without sclerosing therapy. It has a high recurrence rate (about 80-100%) that can be reduced by injection of ethanol, minocycline or tetracycline. The recurrence rate is reduced by about 20% with sclerosing therapy. Another treatment is fenestration or deroofing that can be done either laparoscopically or with open surgery. This involves creating a small window in the cyst and fluid drained through it. Laparoscopic deroofing is preferred; however, due to its limited accessibility and larger size of liver cysts, it is prudent to go with open fenestration. The recurrence rate of laparoscopic fenestration ranges from 0-20%. Cysts can be excised completely with the removal of a segment of liver, but it carries up to 50% morbidity. Liver transplantation is also an option, if the quality of patients life is dramatically compromised.