Pancreatic neuroendocrine tumors

Gastrinomas are one of the more common hormone-releasing NETs in the pancreas and may also occur in the duodenum (small intestine’s first section). Sometimes there are multiple tumors. Gastrinomas release gastrin, which boosts stomach acid. Symptoms cause Zollinger-Ellison syndrome (ZES) and include:

• Diarrhea
• Peptic ulcers (painful sores on the lining of the stomach or small intestine)
• Steatorrhea (oily stools)

Insulinomas are another common, hormone-releasing pancreatic NET. Diagnosis requires staying in the hospital for several days for testing. The tumors release extra insulin, which leads to:

• Hypoglycemia (low blood sugar, which can cause neuroglycopenia, or brain function interference)
• Obesity

These tumors release glucagon, a hormone that increases blood sugar. Symptoms include:

• Anemia (low red blood cell count)
• Blood clots
• Diabetes
• Glossitis (swollen and inflamed tongue)
• Necrolytic migratory erythema (particular rash around the genitals, anus, buttocks, groin and lower legs)
• Unintended weight loss

These tumors release the hormone vasoactive intestinal peptide (VIP), causing:

• Achlorhydria (lack of hydrochloric acid in stomach juices)
• Flushing (warmth and redness in the face)
• Hypercalcemia (too much calcium in the blood)
• Hyperglycemia (high blood sugar)
• Hypokalemia (low potassium)
• Metabolic acidosis (too much acid in the body)
• Watery diarrhea

These rare tumors release somatostatin, leading to:

• Diabetes
• Diarrhea
• Gallstones
• Hyperglycemia (high blood sugar)
• Hypochlorhydria (low stomach acid)
• Steatorrhea (oily stools)
• Unintended weight loss

These rare tumors release pancreatic polypeptide, sometimes causing:

• Belly pain
• Hepatomegaly (enlarged liver)
• Watery diarrhea

Occasionally, pancreatic NETs get discovered when they’re still quite small and slow-growing and haven’t spread. In those cases, we may recommend just monitoring the tumor, since pancreatic surgery comes with some risks. We’re more likely to suggest this approach when tumors aren’t releasing hormones or otherwise causing complications.

If the tumor grows too large, we can then consider surgery.

Overall, we can remove pancreatic NETs more often than pancreatic adenocarcinomas. We may even recommend neuroendocrine tumor surgery for diseases that has spread, as long as it’s not too extensive. For example, we can combine procedures for both the pancreas and the liver.

Our surgeons consider a minimally invasive approach whenever possible, for a shorter hospital stay and faster recovery. We may remove just the tumor or a larger section of the pancreas. One such treatment, the Whipple procedure, removes:

• Head of the pancreas
• Duodenum
• Gallbladder
• Nearby lymph nodes

Even if we can’t remove all the cancer, we may still recommend surgery to reduce the size of a tumor. This approach, called debulking, can keep the disease under control for a while.

For diseases that have spread more widely, our team has many effective options, including some not widely available. Our tumor board helps determine which ones are most likely to work, with the fewest side effects.

Since even metastatic disease tends to grow slowly, many people eventually need a range of therapies over a number of years. We take special care with pacing and sequencing of treatment so you have options when you need them.

Options include:

• Somatostatin analogs (SSAs): These medications are one type of drug therapy for neuroendocrine tumors. They mimic the hormone somatostatin, which most pancreatic NETs will take into their cells. SSAs are typically the first therapy tried when surgery isn’t possible or the disease requires more treatment. Monthly injections can control cancer growth and relieve symptoms tied to hormone release.
• Liver therapy: When we can’t remove liver tumors with surgery, other treatments can shrink them fairly quickly.
• Peptide receptor radionuclide therapy (PRRT): We deliver targeted radiation with a molecule taken up by pancreatic NET cells. The radiation can stop cancer from progressing for a number of years. Unlike surgery or more focused liver treatment, PRRT hits cancerous cells across the body. Since we can only use it so many times, we may recommend saving it until needed.
• Clinical trials: We develop new medications and other treatments through clinical trials and may have one that fits your needs.
• Targeted therapy: Another type of drug therapy, these emerging medications interfere with the ways tumors grow. We often turn to targeted therapy when tumors aren’t good matches for PRRT.
• Chemotherapy: This drug therapy destroys rapidly dividing cells, with the potential to shrink tumors and reduce the amount of disease. Different types of medicines may be needed to treat well-differentiated, slower-growing tumors than for poorly differentiated, more aggressive tumors.
• Radiation therapy: Radiation given by a machine outside the body can treat metastatic sites in the bones and lungs.
• Other medications: We may recommend other supportive drugs such as medicines that block gastric acid (for gastrinomas).