Pancreatic Neuroendocrine Tumor

Pancreatic neuroendocrine tumors (pancreatic NETs, also called islet cell tumors) are rare tumors that start in your pancreas’ endocrine cells. They’re a type of neuroendocrine tumor.

Your pancreas is a flat pear-shaped gland tucked beside your stomach and small intestine. Endocrine cells in your pancreas make hormones that manage digestion and blood sugar levels.

These tumors can be cancerous (malignant) or benign (noncancerous). Without treatment, malignant tumors may spread to other areas of your body.

Types of pancreatic neuroendocrine tumors

There are several types of pancreatic NETs, each with different characteristics:

• Insulinomas are the most common type of functioning pancreatic NET. About 10% of insulinomas are cancerous. Insulinomas release insulin, the hormone that keeps your blood sugar from getting too high.
• Gastrinomas affect cells that release gastrin, which triggers your stomach to produce gastric acid. About 60% of gastrinomas are cancerous.
• Glucagonomas are often cancerous. They affect the cells that release glucagon, the hormone that keeps your blood sugar from getting too low.
• VIPomas can be cancerous. “VIP” stands for “vasoactive intestinal peptide.” This hormone relaxes the muscles in your stomach and bowels and manages the balance of sugar, salt and water in your digestive tract.
• Somatostatinomas are slow-growing cancerous tumors that release somatostatin. This hormone manages several bodily functions.

Symptoms of pancreatic neuroendocrine tumors

Pancreatic NET symptoms may cause several different symptoms. Common symptoms include:

• Severe acid reflux
• Diarrhea
• Fatigue
• Frequent urination, increased thirst and other symptoms of swings in blood sugar levels
• Indigestion
• Loss of appetite
• Nausea and vomiting
• Uncomfortable flushing of your face and neck, wheezing and other carcinoid syndrome symptoms
• Unexplained weight loss
• Big swings in blood sugar, up or down

Pancreatic neuroendocrine tumor causes

Researchers don’t know the exact cause. Some pancreatic NETs happen alongside other conditions. For example, about 5% to 10% of people with insulinomas or glucagonomas also have multiple endocrine neoplasia type 1 (MEN1).

Complications

The most significant complication is that cancerous pancreatic NETs can spread (metastasize) to your bones, liver or lungs.

How doctors diagnose pancreatic neuroendocrine tumors

A healthcare provider will do a physical examination. They’ll ask about your symptoms. They may ask when your symptoms started and if they’re getting worse. They’ll also ask if anyone in your biological family has certain inherited disorders that increase pancreatic NET risk.

They may do the following tests:

• Abdominal computed tomography (CT) scan
• Blood tests, including specific tests for hormone levels, which can mean tumors are releasing lots of hormones
• Endoscopic ultrasound (EUS)
• Endoscopic retrograde cholangiopancreatography (ERCP)
• Magnetic resonance imaging (MRI)
• Neuroendocrine positron emission tomography (PET) scan

Providers use these test results to see if a tumor is functioning or non-functioning. Functioning tumors release unusually large amounts of hormones. Non-functioning tumors don’t release hormones. Test results also help providers identify the type of pancreatic neuroendocrine tumor.

Your provider may refer you to an interventional radiologist for a needle biopsy. This is a procedure to get tissue samples for lab tests. A medical pathologist will examine the tissue for signs of cancer.

Pancreatic neuroendocrine tumor stages and grades

Healthcare providers use cancer staging systems to set cancerous tumor stages and grades. Cancer stages describe tumor size and if the tumor is spreading to nearby lymph nodes or more distant areas of your body.

Cancer grades describe how fast the cells are multiplying. They also describe the cells’ appearance. Cancer cells’ appearance changes as the disease gets more aggressive.

The stages of cancerous pancreatic neuroendocrine tumors are:

• Stage I. The tumor measures less than 2 centimeters (cm) (about 3/4-inch) across and hasn’t spread from your pancreas.
• Stage II. It measures more than 2 cm (3/4-inch) across and/or has spread into your duodenum (the first part of your small intestine) or your bile ducts.
• Stage III. The tumor has spread to nearby lymph nodes, nearby organs or large blood vessels.
• Stage IV. The tumor is in more distant organs and tissues like your liver or bones.

Pancreatic NET grades are:

• Well-differentiated grade 1. Cancer cells aren’t multiplying very fast, and the cells look more like normal cells than abnormal cells.
• Well-differentiated grade 2. The cells have characteristics that fall in between those of low- and high-grade tumors.
• Well-differentiated grade 3. The cells are multiplying more quickly, and cells look more abnormal.
• Poorly differentiated NET. The cells are multiplying very quickly, and they look very abnormal. This is the most aggressive grade. Healthcare providers may call this grade high-grade neuroendocrine carcinoma (NEC) or small cell cancer.

What are treatments for pancreatic neuroendocrine tumors?

Treatment depends on your situation. Treatment for early-stage pancreatic NET is a pancreatectomy to remove the tumor. This is a treatment for cancerous and noncancerous tumors. Specific surgeries vary depending on the tumor’s location in your pancreas.

For example, your surgeon may use terms like “head” and “tail” when they talk about a 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:

• Whipple procedure. This is the most common surgical treatment for pancreatic neuroendocrine tumors. In this procedure, surgeons remove the head of your pancreas and several nearby organs.
• Central pancreatomy. In this procedure, surgeons remove the central body part of your pancreas, leaving the pancreas’ head and tail.
• Distal pancreatomy. In this surgery, they remove your pancreas’ tail. They may remove part of the pancreas body and some or all of your spleen. (Your spleen and pancreatic tail are closely connected.)

Surgery may not be an option if you have an advanced form of pancreatic NET. Your oncologist may recommend other treatments, including:

• Hormone therapy
• Peptide receptor radionuclide therapy (PRRT)
• Tyrosine kinase inhibitors
• Chemotherapy

Your oncologist may recommend specific treatments for liver cancer if a pancreatic NET has spread to your liver.

Recovery time

Your recovery time will depend on the type of surgery you have. For example, it may take several weeks for you to recover from a Whipple procedure. You’ll be in the hospital for five to seven days and be able to get back to daily activities after eight to 12 weeks.

When should I contact my surgeon?

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. The best way to be sure is to talk to your provider.

What are the survival rates for pancreatic neuroendocrine tumors?

Cancer survival rates are estimates of the percentage of people who were alive five years after they received a diagnosis. American Cancer Society data shows the following five-year survival rates:

When you think about survival rates, it’s important to remember that the rates reflect the overall experience of people with pancreatic neuroendocrine tumors. Factors like the kind of tumor, tumor stage, your age and your overall health make a difference.

Talk to your surgeon and oncologist if you have questions about survival rate data. They know you and your situation and are your best resource for information about what you can expect.

What’s the life expectancy for someone with a pancreatic neuroendocrine tumor?

That’s hard to say. In general, people who are diagnosed with earlier-stage pancreatic NET and receive treatment before it spreads 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.