Neuroendocrine liver cancer develops in cells that produce hormones in response to nerve signals. Most neuroendocrine liver cancers spread from other organs.

Liver cancer accounts for more than 700,000 deaths around the world each year. The most common type of liver cancer is hepatocellular carcinoma, which makes up about 75% of cases.

Neuroendocrine liver cancer is a rare type of liver cancer that develops in neuroendocrine cells. Neuroendocrine tumors that start in the liver are extremely rare, with only about 200 cases reported.

Most neuroendocrine liver cancers spread primarily from the gastrointestinal tract or respiratory tract.

In this article, we take a deeper look at neuroendocrine liver cancer, including causes, symptoms, and treatment options.

Neuroendocrine tumors develop in neuroendocrine cells. These special cells produce hormones in response to electrical information delivered by nerves. They’re spread throughout your body but are particularly common in your gastrointestinal tract and lungs.

Neuroendocrine cancer that starts in the liver is extremely rare, and little is known about how to best manage it. It tends to develop slowly and usually isn’t diagnosed until it’s in a late stage.

In a handful of cases, neuroendocrine liver cancer mixed with hepatocellular carcinoma has been reported. Hepatocellular carcinoma is the most common type of liver cancer.

Most cases of neuroendocrine liver cancer spread from your gastrointestinal or respiratory tract. Spread to the liver occurs in anywhere from 27–90% of neuroendocrine tumors that develop in other locations.

Cancer that spreads from other locations is also called metastasized cancer. Metastasized cancer is also called stage 4 cancer.

Neuroendocrine liver cancer often doesn’t cause symptoms until the tumor grows large.

As the tumor grows, you may experience symptoms such as:

About 20–30% of neuroendocrine tumors produce hormones that cause symptoms throughout your body. Tumors that create hormones are called functioning tumors.

Functioning tumors can cause collections of symptoms that are known as paraneoplastic syndromes. Functioning liver tumors can cause a rare type of paraneoplastic syndrome called carcinoid syndrome.

Typical symptoms of carcinoid syndrome include:

Most neuroendocrine liver tumors spread from other parts of your body. Cancer can spread to your liver when cells reach your bloodstream or lymph system.

Researchers still aren’t entirely sure why some neuroendocrine tumors start in the liver. Some researchers theorize that they’re caused by ectopic pancreatic tissue. Ectopic pancreatic tissue is when pancreatic cells develop in areas outside your pancreas.

Another theory is that neuroendocrine liver cancer may start in stem cell-like cells in ducts inside your liver that carry bile.

The average age of diagnosis of neuroendocrine cancer that starts in the liver is about 47 to 50. Very few cases have been reported under the age of 40, and it seems to be diagnosed about equally in men and women.

Neuroendocrine liver tumors can be difficult to diagnose in the early stages since they often don’t cause symptoms. Tumor markers such as alpha-fetoprotein that can help diagnose other types of liver cancer don’t seem to help with neuroendocrine tumor diagnosis.

Doctors can identify neuroendocrine liver tumors with imaging such as:

A biopsy can be used to confirm the diagnosis and differentiate neuroendocrine cancer from other types. A biopsy is a tissue sample taken so that doctors can analyze the cells microscopically in a laboratory.

For neuroendocrine liver cancer, this sample is usually taken after surgery to remove the tumor. A fine needle biopsy hasn’t been found to be accurate.

A biopsy isn’t needed if lesions in your liver are seen by imaging tests and if you already have a confirmed diagnosis of neuroendocrine tumors (NETs) elsewhere in the body.

Doctors are still learning the best way to treat neuroendocrine liver cancer. Liver surgery with the intention to cure is the treatment of choice for tumors that can be surgically removed. Surgery is only a feasible option in 10–25% of people with metastatic liver neuroendocrine cancer.

The type of surgery you receive is dependent on factors such as the size and location of the cancer.

Surgery might involve:

Research suggests that people with neuroendocrine cancer that starts in the liver and who receive surgery live at least 5 years in about 74% of cases. Cancer returns in about 18% of people.

In a 2021 study, researchers found no significant difference in survival rates for small intestine neuroendocrine tumors that had and hadn’t spread to the liver among 123 people. The survival rates reported in the study were as the following:

Survival timeNo spread to liverSpread to liver
1-year89.0%89.5%
5-year68.4%69.5%
10-year52.8%33.2%
20-year31.0%3.6%

More favorable outcomes have been reported in people who receive aggressive treatment with surgery and liver transplant. People who aren’t eligible for a liver transplant might have poorer survival.

The following scenarios make you ineligible for a liver transplant:

  • The cancer spread outside the liver.
  • The liver cancer occurs in the bile duct (intrahepatic cholangiocarcinoma).
  • There’s a hepatocellular carcinoma larger than 5 centimeters (2 inches) or 3 tumors larger than 3 centimeters (1 inch).
  • You have severe heart disease.
  • You have uncontrolled sepsis.
  • You currently have alcohol or substance use disorder.
  • You have AIDS.
  • You’re not following prescribed treatment or lack of social support.
  • You have certain anatomical factors such as morbid obesity.

Neuroendocrine tumors start in cells that produce hormones in response to neurological signals. It’s extremely rare for these types of tumors to start in the liver. Most liver neuroendocrine tumors spread from other locations, such as the lungs or gastrointestinal tract.

Researchers are continuing to examine the best way to treat neuroendocrine tumors. As of now, surgery is considered the only potential cure.