What Are Liver Lesions?

Written by Angela Nelson
Medically Reviewed by Zilpah Sheikh, MD on September 22, 2023
7 min read

Liver lesions are groups of abnormal cells in your liver. Your doctor may call them a mass, cyst, or tumor.

Noncancerous, or benign, liver lesions are common and can be found in up to 30% of people over age 40. Most liver lesions don't cause any health issues, but some form as a result of cancer. So, it's important to seek proper care if your doctor finds lesions on your liver.

Benign liver lesions

There are several common causes of benign liver lesions: a cyst, a hemangioma, and focal nodular hyperplasia (FNH). These benign liver lesions are noncancerous.

A different type of liver lesion called a hepatic adenoma starts as benign but has the potential to become cancerous, or malignant. "It means that over time…it could turn into cancer," says Richard Sterling, MD, a hepatologist at VCU Health and the section chief of hepatology at VCU's School of Medicine and chief clinical officer at the VCU's Stravitz-Sanyal Institute for Liver Disease and Metabolic Health.

Malignant liver lesions

Hepatocellular carcinoma is the most common type of malignant liver lesion and accounts for over 80% of all primary liver tumors. Malignant liver lesions are cancerous and can start in the liver or metastasize (spread) from a primary tumor elsewhere in the body.

"It's not one-size-fits-all," says Sterling. Instead, there are many potential causes of liver lesions and factors that can lead to a higher likelihood of developing a malignant (cancerous) liver lesion.

What causes benign liver lesions?

Certain medications, including oral contraceptives and steroid drugs, can raise the risk of developing benign liver lesions.

What causes cancerous liver lesions?

Hepatitis B or C. These viruses are the main cause of liver cancer.

"If you have hepatitis B, you're at risk for liver cancer even if you don't have a lot of scarring on your liver," Sterling says. "If you have hepatitis C, particularly if you have advanced fibrosis or cirrhosis, you can still develop cancer. Even if you got rid of the virus, which we can do pretty easily now, it doesn't mean that you're out of the woods completely."

Cirrhosis. You may get this condition if you have hepatitis B or C or if you're a heavy drinker. It happens when scar tissue grows in place of damaged liver cells, and it can lead to cancer. About 80% of people who are diagnosed with the most common type of liver cancer, hepatocellular carcinoma, have cirrhosis.

Iron storage disease (hemochromatosis). This is one of the most common genetic disorders in the U.S. It makes your body take in too much iron from food. The extra iron gets stored in your organs, including your liver.

Obesity. Metabolic dysfunction-associated steatotic liver disease (MASLD) is typically seen in people who are overweight or have obesity. The condition is caused by a buildup of fat in the liver. Earlier, MASLD was known as nonalcoholic fatty liver disease.

Arsenic. This chemical occurs naturally but can be poisonous. It's sometimes found in drinking water.

Aflatoxin. This toxin is created when mold grows on grain and nuts that aren't stored the right way. It's very rare in the U.S. Anyone can have a liver lesion, but some things can make you more likely to have cancerous ones.

 

Liver lesions often don't cause any symptoms. Many people only find out they have one when they go for an imaging test, like an ultrasound, for a different health issue.

"Liver lesions are often discovered incidentally," Sterling says. "There is usually another reason someone is getting an ultrasound, a CAT scan, or an MRI, and those scans show spots on the liver."

If liver lesions do cause problems, your symptoms could include:

If your doctor thinks you might have a liver lesion, they'll probably recommend additional testing:

Blood tests. They might use these to test for viral hepatitis or to see how well your liver is working. They may also want to check your level of a certain protein called alpha-fetoprotein (AFP). High amounts of AFP can be a sign of liver cancer.

Imaging tests. These can show where a lesion is on your liver and how big it is. An MRI scan uses powerful magnets and radio waves to make detailed images of your liver. A CT scan is a series of X-rays put together to make a more complete picture. A PET scan uses a special dye that makes your liver show up more clearly. And an ultrasound uses high-frequency sound waves to make live images of your liver.

Biopsy. To rule out cancer, your doctor may want to take a small sample of the lesion to look for problem cells.

Treatments for liver lesions depend on whether the lesion is cancerous or not. For a small cyst, doctors may take a "watch-and-wait" approach, according to Sterling. If oral contraceptives or hormone replacement therapies are believed to be the cause of liver lesions, specifically with hepatic adenomas, stopping the medication can cause the lesion to get smaller, he adds.

Sometimes, multiple benign liver lesions grow quite large — a condition called polycystic liver disease — that can cause pain. Even though the cysts aren't cancerous, Sterling notes, "Some of those patients need to get a liver transplant because the cysts are so massive there's just no more room in the body."

If you have a liver lesion, Sterling suggests getting it checked by a gastroenterologist or hepatologist (liver specialist) to figure out the type of lesion, assess for underlying liver disease, and come up with a treatment plan.

If the lesion is cancerous, you might need one or more of these treatments:

Ablation. This minimally invasive procedure targets the tumor to kill cancer cells. There are several different kinds of ablation:

  • Radiofrequency ablation uses high-energy radio waves via needles that are placed into the tumor to kill cancer cells with heat.
  • Microwave ablation uses a needle inserted into the tumor that creates high heat and kills cancer cells.
  • Cryoblation kills cancer cells by freezing them.
  • Chemical ablation injects pure alcohol (ethanol) into the tumor to kill cancer cells.

Embolization. Anticancer medications are injected into the arteries that carry blood to the tumor. Sometimes, it's possible to block the blood vessels going to the tumor, which starves the cancer cells of blood and kills the tumor.

Radiation. Multiple kinds of radiation allow precise targeting of liver tumors with minimal damage to healthy cells.

Chemotherapy. These drugs kill cancer cells or control the growth of tumors. Different chemotherapy drugs (or combinations of drugs) are used depending on the type of cancer and how fast tumors are growing.

Can lesions on the liver heal by themselves?

Cancerous liver lesions require treatment, but Sterling notes that some benign liver lesions may shrink or disappear over time.

You can lower your chances of getting cancerous liver lesions if you exercise, stay at a healthy weight, and drink only in moderation (up to two drinks a day for men and one for women).

And you can do a few things to keep from getting hepatitis B or C, which are responsible for 80% of liver cancer cases. You can get vaccinated against hepatitis B, wear condoms when you have sex, and don't share needles if you use them to do recreational drugs.

  • Most liver lesions are benign and harmless, but some can be cancerous, so it's important to follow your doctor's instructions for monitoring liver lesions.
  • Malignant liver lesions are often linked to risk factors such as hepatitis B or C, cirrhosis, hemochromatosis, obesity, and exposure to toxins.
  • Liver lesions often cause no symptoms.
  • Treatment depends on the lesion type: Benign lesions may be monitored, while cancerous lesions may require treatment.
  • The most common treatments for cancerous liver lesions include ablation, embolization, chemotherapy, radiation, or surgery. 
  • Maintaining liver health and avoiding hepatitis infection can help prevent liver lesions.

What are focal liver lesions?

Focal liver lesions refer to the abnormal masses in the liver that are seen on imaging tests. Focal liver lesions can be solid or fluid-filled and can be noncancerous (benign) or cancerous (malignant).

How serious is a liver lesion?

Liver lesions are common and will affect up to 30% of adults over age 40. Most liver lesions are benign and require no treatment.

What percent of liver lesions are cancerous?

Benign (noncancerous) liver lesions are much more common than cancerous liver lesions. Liver cancer accounts for just 5.7% of all cancer cases.