What Are Liver Lesions?

Liver lesions are abnormal growths of cells in the liver. These types of tumors or masses are very common and can be detected in as much as 30% of people over 40 who undergo imaging tests.

The majority of liver lesions are benign (noncancerous) and usually don't require treatment. But in some cases, liver lesions are a sign of disease or cancer and should be treated.

Benign Liver Lesions

These are non-cancerous masses that form in the liver, and they don't typically cause health problems.

Types of Benign Liver Lesions

There are different types of benign liver lesions.

Hepatic Hemangioma

Hepatic hemangioma is the most common type of liver lesion, consisting of clusters of small blood vessels. Around 20% of the general population have hemangiomas. They don't typically cause symptoms, so they can be left untreated.

But in rare cases, they can cause abdominal pain, nausea, and early satiety (feeling full). Women are more likely to have hemangiomas than men.

Focal Nodular Hyperplasia (FNH)

This is the second most common type of liver lesion, and it is seen more often in women than men. In 80% of cases, FNH is found in women between the ages of 20 to 50. An FNH lesion can grow bigger or smaller, but regardless of changes to its size, it does not become cancerous.

Benign Hepatic Cyst

This type of lesion contains a clear, bile-like liquid and does not usually cause any symptoms. In rare cases, if the cyst is large, it may cause abdominal pain or nausea, vomiting, and early satiety. Anywhere from 2.5% to 18% of the general population could have benign cysts in their liver.

Hepatic Adenomas

These are uncommon liver lesions that develop predominantly in young women. It can be caused by long-term oral contraception use or synthetic testosterone use. Hepatic adenomas can sometimes cause abdominal discomfort.

About 5% of them will transform into hepatocellular carcinoma (HCC)—a type of liver cancer. In about 10% of cases, the lesion will spontaneously rupture or cause internal bleeding. This is most likely during menstruation, pregnancy, and the postpartum period.

If you have hepatic adenomas, your healthcare provider will likely recommend that you avoid taking oral contraceptives. Surgery to remove them will probably also be recommended.

Rarer types of benign liver lesions are hepatobiliary cyst adenoma, bile duct adenoma, and inflammatory pseudotumor.

Diagnosis

The diagnosis of benign liver lesions is usually incidental. Often, the lesions are detected on magnetic resonance imaging (MRI) or other imaging tests for abdominal pain or an unrelated health problem. 

Other diagnostic tools may be used in cases where it is not clear from the imaging whether the lesion is benign or cancerous. For instance, a biopsy may be done so that cells from the tumor may be removed with a needle and sent to a lab for testing.

Treatment

Most of the time, these lesions do not cause any discomfort or health issues, and your healthcare provider often won't recommend any treatment. In rare situations, a benign liver lesion may cause symptoms like nausea or abdominal discomfort, and surgical removal could be recommended.

Some benign liver lesions may also have a high risk of rupture or transformation into cancerous tumors. In those cases, your healthcare provider will likely recommend surgical removal.

Malignant Liver Lesions

Although most lesions in the liver are benign, some liver lesions are cancerous.

Types of Liver Cancer

There are two major types of primary liver cancer (cancers that start in the liver):

• Hepatocellular carcinoma (HCC): This is the most common type of liver cancer. HCC tumors are three times more common in men than women, and they are usually preceded by liver cirrhosis.
• Fibrolamellar carcinoma: This is a subtype of HCC, where fibrous bands separate the cells of the tumor. Fibrolamellar carcinoma is seen more in women than men and risk factors are not known.
• Cholangiocarcinoma: This is the cancer of the bile duct. With cholangiocarcinoma, malignant liver lesions develop in the branches of the bile duct. These tumors can appear in the bile duct regions that are in the liver, or further down, in parts of the bile duct near the small intestine.

Rare types of liver cancer include liver angiosarcoma and hepatoblastoma.

Symptoms

Usually, liver cancer has non-specific symptoms like fatigue, unintentional weight loss, vague abdominal pain, and loss of appetite. If there's biliary obstruction, jaundice can develop. Jaundice is a yellow discoloration of the skin and the white of the eyes.

Other liver cancer symptoms include unintentional weight gain, fever, nausea, vomiting, and generally feeling unwell. Sometimes the urine can have a dark color.

Risk Factors

Some of the risk factors for developing cancerous liver lesions include:

• Hepatitis B or C infection: These viral infections are the leading causes of liver cancer.
• Cirrhosis: Cirrhosis may be a precursor to liver cancer. It develops when long-term damage causes scar tissue build-up in the liver. Many factors can cause this damage, including excessive alcohol intake and hepatitis B or C infection. Liver lesions discovered in a person who has cirrhosis are most likely to be hepatocellular carcinoma.
• Iron storage disease (hemochromatosis): This is a condition where the body stores excessive amounts of iron in the liver and other organs.
• Sex: Men are more likely to have liver cancer than women
• Aflatoxin exposure: Aflatoxin is a toxin that's produced by mold that grows on nuts and grains.

Diagnosis

Malignant liver lesions are diagnosed using several types of tests. If your healthcare provider suspects you have liver cancer, any of these may be ordered:

• Blood tests like alpha-fetoprotein (AFP) tumor marker and liver function tests (LFTs)
• Imaging tests like ultrasound, computerized tomography (CT) scan, and MRI
• A biopsy involves surgically removing some tissue or cells from the tumor and sending it to a lab for further testing

Treatment

There are different options available to treat cancerous liver lesions:

• Surgical removal of the tumor
• Liver transplant
• Ablation therapy
• Embolization therapy involves cutting off blood supply to the tumor, so it "starves" and cannot grow.
• Targeted therapy drugs
• Chemotherapy
• Immunotherapy

Depending on the size, stage, and type of tumor, you may need to have a combination of these therapies.

Prevention

Some tangible steps you can take to prevent liver cancer are:

• Prevent hepatitis B or C infection by practicing safe sex and getting vaccinated against hepatitis (if you weren't already as a child).
• If you already have hepatitis B or C, talk to your healthcare provider about treatments that can help reduce your risk of developing cirrhosis and liver cancer.
• Limit your alcohol intake.
• Quit smoking.
• Learn about your family history, especially relating to liver issues.

Summary

Liver lesions are usually nothing to worry about. Nevertheless, if you're experiencing abdominal pain or discomfort, or any of the symptoms of liver cancer, you should see your healthcare provider. And if liver lesions are accidentally discovered during an imaging test, your healthcare provider will be able to discuss the significance of the lesions and guide your next steps in treatment.