Benign liver tumors are abnormal growths of cells or tissue of the liver; the tumors are noncancerous, or benign, and are quite common. They do not spread to other areas of the body and usually pose no serious health risk. In most instances, benign liver tumors are not diagnosed because they cause no symptoms. When they are detected, it is usually due to medical imaging tests performed for other unrelated reasons.
There are three common types of benign liver tumors:
Hemangiomas: the most common type of benign liver tumor. Liver hemangiomas usually occur as a small single abnormal collection of blood vessels. Occasionally liver hemangiomas can become large or occur in multiples.Focal Nodular Hyperplasias (FNH): the second most common type of benign liver tumor; they typically occur in women between the ages of 20 and 30. These tumors do not cause symptoms and rarely require treatment.Hepatocellular Adenomas: the least common type of benign liver tumor; they occur most often in women of childbearing age and have been linked to use of oral contraceptives. Because adenomas are asymptomatic, most are never detected and rarely cause problems.
It is not known what causes benign liver tumors to develop. Some doctors believe that hemangiomas are congenital. In most people, benign liver tumors do not grow and never cause any signs and symptoms. However, in a small number of patients, liver tumors will grow causing complications and require treatment. It is unclear why this happens.
Focal nodular hyperplasia and hepatocellular adenomas have been linked to oral contraceptive use. Hepatocellular adenomas in particular, are susceptible to the influence of the female hormone estrogen.
Most benign liver tumors do not cause any symptoms. Like liver cysts, they are generally discovered during imaging tests for other conditions. When symptoms do occur, it is often caused by the size of the tumor and/or the proximity to other organs. In very rare cases, if the tumors are large or causing pain, surgical removal may be recommended.
In most cases, benign liver tumors are not detected because they cause no symptoms. When they are detected, it is usually because a patient required a medical imaging test, such as an ultrasound, CT test or MRI, for another condition.
Physicians will usually only recommend surgical removal of a common hemangioma if it is causing discomfort.
Focal nodular hyperplasia and hepatocellular adenoma patients may be monitored using imaging scans such as CT or MRI. Hepatocellular adenomas should be carefully monitored as they can grow, bleed or become cancerous. Surgical removal may be necessary depending on the size of the adenoma. In addition, female patients may be instructed to stop using oral contraceptives or hormone supplementation. Hepatocellular adenomas may grow in women who take hormone pills, so physicians often advise discontinuing birth control pills or hormones to prevent further growth. The goal of this treatment is to shrink the tumor, but if this does not occur, surgery may be necessary.