Pancreatic neuroendocrine tumors (islet cell tumors) are tumors that start in your pancreas’ endocrine cells. These rare tumors cause symptoms that may feel like common medical issues. Early diagnosis and treatment make a difference, with more than 90% of people with this condition being alive five years after diagnosis.
Pancreatic neuroendocrine tumors (also called islet cell tumors or pancreatic NETs) are rare tumors that start in your pancreas’ endocrine cells. Your pancreas is a flat pear-shaped gland tucked beside your stomach and small bowel. Endocrine cells in your pancreas make hormones that manage digestion and blood sugar levels. A pancreatic NET may affect your digestive system or your blood sugar levels.
Pancreatic neuroendocrine tumors can be cancerous or noncancerous.
They’re rare. The most recent data estimates that 5 in 1 million people develop a type of pancreatic neuroendocrine tumor.
Healthcare providers classify pancreatic neuroendocrine tumors as being functioning or nonfunctioning:
There are several types of pancreatic NETs, each with different characteristics. Some but not all of them are cancerous, meaning they can spread from your pancreas to other parts of your body. Some cause other conditions or have links to other conditions. All the tumors below are functioning pancreatic NETs.
Pancreatic neuroendocrine tumor types are:
Symptoms vary depending on the type of pancreatic NET, but common symptoms include:
Researchers don’t know the exact cause. Approximately 10% of pancreatic neuroendocrine tumors are linked to inherited conditions or syndromes.
Healthcare providers do physical examinations, including asking about specific symptoms, how long you’ve had symptoms and if your symptoms are getting worse. They’ll ask about your medical history, including if anyone in your biological family has certain inherited disorders that have an association with pancreatic neuroendocrine tumors.
Healthcare providers do several tests, including:
Healthcare providers use test results to establish pancreatic neuroendocrine tumor stages, grades and whether the tumors are functioning or nonfunctioning:
Healthcare providers use the TNM cancer staging system to classify pancreatic NETs. (In TNM staging, T stands for tumor size and location, N stands for whether tumors affect nearby lymph nodes and M stands for whether tumors have metastasized.) The stages of pancreatic neuroendocrine tumors are:
Pancreatic NET grades describe how quickly a cancerous tumor may grow and spread. Healthcare providers set tumor grades based on what a medical pathologist learns about the tumor’s cells. The tumor grades are:
The most common treatment is a pancreatectomy to remove a tumor. Specific surgeries vary depending on tumor location in your pancreas. Your healthcare provider may use terms like “head” and “tail” when they talk about specific surgery. That’s because your pancreas is shaped like a fish, with a wide head, a medium-sized middle or body and a narrow tail. Common pancreatectomies are:
Healthcare providers may do other types of surgery and the following treatments:
There are many ways to treat pancreatic NETs and just as many side effects. Side effects will vary depending on the treatment type:
As you go through treatment, consider talking to your healthcare team about palliative care. Palliative care offers support services and care for people with serious illnesses, including ways to manage treatment side effects.
Survival rates vary depending on the pancreatic NET type, its grade and whether the tumor was in other parts of your body at the time of diagnosis. The National Cancer Institute (U.S.) tracks the rate of people with cancer who were alive five years after diagnosis. The five-year survival rates for pancreatic NETs are:
If you’re wondering about survival rates, it’s important to remember that this is information based on other people’s experiences with a pancreatic NET. It’s also information based on what’s happened in the past. You’re unique, and so is your potential survival rate. Talk to your healthcare team about survival rate data. They know you and your situation, which means they’re your best resource.
That’s hard to say. In general, people who receive treatment before a pancreatic NET has spread may have nearly normal life expectancies, particularly if they’re alive more than five years after diagnosis. Just like survival rates, your healthcare team is your best resource for information about your life expectancy.
Just as there’s no single type of pancreatic neuroendocrine tumor, there’s no single or best way to take care of yourself. In general, you should:
Pancreatic neuroendocrine tumors are rare. You may feel like no one else can understand what you’re experiencing. If that’s your situation, ask your provider if there are support groups you can join.
You should see your healthcare provider if you notice changes in your body, like your original symptoms worsening. These changes might be unrelated to your condition, and the best way to be sure is to talk to your provider.
Pancreatic neuroendocrine tumors are rare, and you may not know much about them. Here are some questions you may want to ask your healthcare provider:
Adenocarcinomas are cancers that start in your glandular epithelial cells. These cells are in glands lining your organs, including your pancreas.
Pancreatic neuroendocrine tumors are only in endocrine cells in your pancreas. In general, pancreatic neuroendocrine tumors are slower growing and have a much better prognosis compared to pancreatic adenocarcinoma.
All serious medical conditions are challenging. But the challenges may feel like they’re doubled or even tripled when the condition in question is a rare one like a pancreatic neuroendocrine tumor (pancreatic NET). You may find yourself hunting for information about these tumors, which affect specific cells in your pancreas. And you may feel overwhelmed as you try to process what you’re learning and anxious about what happens next.
Your healthcare providers understand that having a rare disease like a pancreatic NET may be an upsetting experience. If you have a pancreatic NET and have questions, don’t hesitate to ask your team for information about what you can expect.
Last reviewed by a Cleveland Clinic medical professional on 10/10/2023.
Learn more about our editorial process.