What Are Pancreatic Neuroendocrine Tumors (NETs)?
It's natural to feel a little overwhelmed when you get news that you have a pancreatic neuroendocrine tumor (NET). If you're like most folks, it's probably be the first time you've heard of the condition. So take a little time now to tackle the topic. That will make it easier to work with your doctor on a plan of action to help you feel better and treat your tumor.
Pancreatic NETs grow in your pancreas, a gland in your belly that has two big jobs. It makes juices to digest food, and it makes hormones, which are chemicals that control different actions in your body. NETs grow in the cells that make hormones.
These tumors usually don't grow as fast as the more common kind of pancreatic cancer. Treatments can remove them, slow their growth, and make your symptoms better.
Every situation is different, and how you get treated depends on what type of NET you have. There are two kinds: "functional" and "nonfunctional."
Functional means the tumor makes its own hormones and causes symptoms. Nonfunctional tumors don't cause symptoms.
Most nonfunctional NETs are cancerous, which means they can spread to other parts of your body. You may not have symptoms until your tumors get big or spread.
Most neuroendocrine tumors are the functional kind. They can be cancerous, but they aren't always.
Functional NETs get their names from the type of hormone they make. You may hear your doctor use these terms when they describe your condition:
Insulinomas. They're the most common and they're rarely cancerous. They grow in the cells that make insulin. The extra insulin made by your tumor can lead to low blood sugar levels, which can make you feel "off" or pass out, or cause a seizure.
Glucagonomas. They grow in the cells that make glucagon, a hormone that raises your blood sugar. They can cause high blood sugar levels, which can damage your nerves, eyes, heart, kidneys, and gums. About 75% are cancerous.
VIPomas. These tumors grow in the cells that make vasoactive intestinal peptide (VIP), which helps control muscles and nerves in your stomach and intestine. This type of NET is rare. Most VIPomas are cancerous.
Gastrinomas. They happen in people with a rare disorder called Zollinger-Ellison syndrome. These tumors grow in the cells that make gastrin, which controls stomach acid. Over half are cancerous.
Somatostatinomas. Most of these tumors are cancerous. They grow in cells that make somatostatin, a hormone that helps control the production of other hormones, including insulin and gastrin.
Pancreatic neuroendocrine tumor with ectopic ACTH production. This is a very rare tumor that produces adrenocorticotropic hormone (ACTH), a hormone that regulates production of cortisol and androgens.
No one knows what causes pancreatic NETs. People who have family members with a disorder called multiple endocrine neoplasia type 1 (MEN1), which can also affect the pancreas, are more likely to get them.
Other tumor-causing diseases that are passed down in families also raise your chances, including:
- Von Hippel-Lindau syndrome
- Neurofibromatosis type 1
- Tuberous sclerosis
Because nonfunctional NETs often don't cause symptoms until they become large or spread, doctors usually find them at a later stage.
You may have problems like:
- Uncomfortable feeling of fullness after eating
- Lump in your belly
- Pain in your belly or back
- Yellowish skin or eyes
The symptoms of a functional NET depend on the kind of hormone it makes. You might feel:
- Nervous or anxious
- Shaky, dizzy, or lightheaded
- More or less hungry than usual
You could have:
- Weight loss or gain
- A need to go to the bathroom more or less
- Pain in a specific place that won't go away
- A backup of stomach acid into your throat
- Trouble seeing
- Fast heartbeat
- Sweating a lot
- Raised, red rash on your lower leg, around your mouth, or anywhere your skin rubs together
Getting a Diagnosis
Before you get any tests, your doctor may have some questions for you. They'll want to know:
- How have you been feeling?
- When did you first notice changes?
- Do you have pain and where?
- How is your appetite?
- Have you been thirsty?
- Have you lost any weight?
- Have you noticed any skin rashes?
- Are you more tired than usual and when did this start?
- Do you have any medical conditions?
- Do you take any medications?
- Does anyone in your family have an endocrine disorder? What type?
- Do any illnesses run in your family?
Your doctor will do a physical exam and may order some tests that can check where your tumor is growing. Some that you might get are:
X-rays. They use radiation in low doses to make pictures of the inside of your body.
Blood and urine tests. They check your levels of hormones and protein.
CT scans (computed tomography). These are special X-rays that make detailed pictures of your insides.
MRIs (magnetic resonance imaging). They use powerful magnets and radio waves to make pictures of organs and structures inside your body.
PET Scan (positron emission tomograph). A radioactive tracer is injected which helps show any anomoly during a scan.
If your doctor finds a tumor, you may need more tests to figure out its size, how far it has spread, and what type it is. For instance, you may get:
Endoscopic ultrasound. Your doctor puts a thin, flexible tube down your throat or into your rectum to see inside your body. A small device on the end sends out high-energy sound waves that can create an image of your organs, like the pancreas and lymph nodes.
Somatostatin receptor scintigraphy. You'll get a small injection of a radioactive hormone. It attaches to the tumor, which helps the doctor see how large it is.
Biopsy. Your doctor takes a sample of tissue from your pancreas. Usually they use a needle to take out some cells, but sometimes they'll make a small cut instead. After the procedure, they'll check the cells under a microscope.
Questions for Your Doctor
- Do I need more tests?
- What type of NETs do I have?
- How many tumors do you see?
- Have you treated someone with NETs before?
- Is surgery an option for me?
- What other treatment do you recommend?
- How will it make me feel?
- Will my children get NETs, too?
There are a number of treatments for NETs. Doctors can use surgery, chemotherapy drugs, and hormones. Your treatment will depend on:
- What kind of tumor you have (functional or nonfunctional)
- Whether it's cancerous or not
- How far it has spread
Surgery is the most common treatment. It can completely remove some NETs, especially those that aren't cancerous or haven't spread. Your doctor may give you treatments to reduce hormones in some pancreatic NETs before surgery.
Your doctor may be able to get rid of just the tumor. Other surgeries remove different parts of the pancreas and maybe other organs. For example, the Whipple procedure (also called pancreatoduodenectomy) takes out the head of the pancreas and, because of how it's tied into other organs, the gallbladder, part of the small intestine, the end of the bile duct, and sometimes part of the stomach and nearby lymph nodes. If the tumor is large or spreads far, surgery may not remove it all.
Doctors also use surgery to kill cancer cells. Radiofrequency ablation does it with a probe and high-energy radio waves. Cryosurgery freezes them.
Chemotherapy uses drugs to kill cancer cells or to stop them from dividing. You take chemo meds by mouth, or a doctor injects them into a vein or your belly.
Radiopharmaceutical drug therapy with a radioactive intravenous medication, lutetium Lu 177 dotatate (Lutathera) is sometimes used to treat certain neuroendocrine tumors.
Hormone therapy blocks the hormones that help tumors grow. It might help with your symptoms, too. People who have functional tumors that can't be removed with surgery often get this kind of treatment.
There are other methods that can ease specific symptoms. For example, IV fluids can help you feel better when you have diarrhea. For a gastrinoma, your doctor may give you medicines to reduce stomach acid and prevent ulcers. You can take medication to control low blood sugar from an insulinoma.
Taking Care of Yourself
You can help yourself feel better if you pay attention to what and when you eat. Try these tips:
- Rather than three big meals, eat smaller meals more often during the day. It's easier on your stomach and will keep your blood sugar steady.
- Stick to a healthy diet with more fruits, veggies, and whole grains.
- Eat fewer foods that are high in fats, especially animal fats.
- Don't drink alcohol.
Exercise for 30 minutes on most days to help keep your body in shape and your hormones in balance. It might ease pain and nausea. It's also a good way to relieve stress, lift your mood, and help you sleep, too.
Along with medication for your symptoms, you may want to try complementary treatments. Massage and acupressure or acupuncture could soothe pain and help you relax.
Gentle exercise, such as yoga, may give you a sense of contentment and well-being.
Check with your doctor before you start any alternative treatment.
What to Expect
NETs are very different diseases from the much more common type of pancreatic cancer. Compared to those tumors, which usually grow fast, NETs usually grow slowly -- over years, not months -- and treatments can get rid of many of them. A lot depends on the type of tumor, whether it's cancerous, and how much it has spread.
You have the best chance for a complete recovery when your tumor gets removed with surgery. Even if it can't be taken out, treating it can help you live longer and feel better.
It's important to take care of your emotional needs, too. Fortunately, you can turn to plenty of places for help. Make sure you reach out to your family and friends to get their support. They can help in all kinds of ways, big and small. Sometimes just a kind word or an offer to help you with a chore can make a big difference in how you feel.
Also talk to your doctor about how to find a support group near you. You'll get a chance to meet people who are going through the same things you are. Sharing experiences with others who face this condition can give you new insights on how to manage your disease.