Treatment options currently available
Treatment can reduce the number and size of NETs as well as some of the symptoms caused by the tumors. Some choices are available – your doctor will discuss the best options for you based on the type and stage of your NET, as well as your medical history. A pancreatic NET, for example, may require different treatments than a NET of the digestive tract.
Cancer and its treatments can cause side effects in some patients. You may tolerate your treatment well, but knowing what is expected and when to let your doctor know if you experience anything unexpected is essential. Your care team can help you manage the side effects and help you feel more comfortable. The care team might make changes to your treatment, prescribe specific medications or provide advice on adjusting your diet and general lifestyle. You can also read our nutrition ebook for helpful diet tips.
Below is information on some of the available therapeutic options and common side effects of each specific treatment you might receive. Remember that these are all just potential side effects, and the experience of each patient can be different.
Surgical management
Patients with NETs often have surgery to remove the tumors, especially at early stages1,2. The goal of surgery depends on the type of NET, its location in the body and size, as well as whether it has spread from the primary site.
Curative surgery: if an early-stage tumor can be removed entirely and intact with a perimeter of clear, healthy tissue, the surgery can potentially cure cancer, and no other treatment may be required.
Palliative surgery: if the tumor has spread or is too large to remove altogether, surgery to reduce the tumor size may help relieve symptoms and improve the quality of life if the tumor is affecting other organs or producing excessive amounts of hormones. It may be offered in combination with different types of treatment, which might be more effective once the tumor size is reduced.
General side effects of surgery
Many factors will determine your recovery from surgery: your general health, the type and complexity of the surgery, possible complications during surgery and so on. Your doctor should explain the potential side effects of any procedure you might need, but common symptoms after surgery include pain where the surgery took place, bleeding or fluid leaking from the wound, swelling and bruising, infection, fatigue, incisional hernia, and altered function.
Medical management
Somatostatin analogs (SSA), given either daily (short-acting) or monthly (long-acting) as an injection, may help control some symptoms caused by NETs.
SSAs are versions of naturally occurring somatostatin, a hormone produced in the brain and digestive tract that regulates the release of several other hormones and chemicals from internal organs. Injections of SSAs can stop the overproduction of hormones (such as serotonin) that cause symptoms like flushing and diarrhea. There is evidence that SSAs can also slow down the growth rate of some NETs of the digestive tract3.
General side effects of SSAs
The side effects of SSAs can be relatively mild, are usually temporary and can be resolved. They may include loss of appetite, sickness, feeling bloated, stomach pain, fatigue, diarrhea (rare), soreness at the injection site, and changes in heart rate. You might also have raised or lowered blood sugar levels. If you have diabetes, you may need to check your blood sugar more often, and you might need to increase or decrease your medication. Your doctor can help you manage any changes in your medication dose.
While uncommon, having this treatment over many months may cause gallstones, so you might have an ultrasound scan of your gallbladder before you start treatment and then every 6 to 12 months.
Chemotherapy may be an option for some NET types and may sometimes be recommended after surgery for high-grade NETs. Chemotherapy works either by stopping or slowing the growth of cancer cells, which grow and divide quickly.
Chemotherapy is usually given intravenously (IV) in a hospital setting but it should not require you to stay overnight. However, there are also oral chemotherapy agents that your doctor may consider. Your doctor should discuss the best option with you.
General side effects of chemotherapy
There are many chemotherapy agents, and every patient reacts to them differently, so your doctor should discuss potential side effects. Some common ones include fatigue (this can carry on for several months after your treatment ends), sickness, hair loss, increased risk of infection, weight loss, diarrhea and constipation, dry skin and skin rashes, and numbness or tingling in the hands and feet.
Targeted molecular therapies specifically attack cancer cells with minimal damage to healthy cells. They can have different mechanisms of action and affect how cancer cells grow, divide or spread. For example, tyrosine kinase inhibitors may be used in pancreatic NETs to block a process known as angiogenesis (in which the tumors create new blood vessels to maintain a good blood supply that supports their growth).
General side effects of targeted molecular therapies
Each specific treatment may have different side effects. Some possible general side effects may include mouth ulcers, diarrhea, constipation, fatigue, sickness, loss of appetite and weight loss.
Nuclear medicine
Radionuclide therapy, also known as peptide receptor radionuclide therapy (PRRT), is usually used to treat patients with NETs when other types of treatment, such as surgery or chemotherapy, are not suitable or are ineffective (due to the size, location or number of tumors). It is a therapy delivered intravenously and directed against tumors with many somatostatin receptors, which are increased on the cell surface of most NETs. When this therapy is considered, a diagnostic scan is performed to confirm if the tumors are positive for somatostatin receptors. Radiotherapeutic agents can specifically bind to these receptors and emit therapeutic radiation that damages or kills tumor cells.
General side effects of radionuclide therapy
Side effects of this treatment include: pain after treatment, nausea, vomiting, diarrhea, increased liver enzymes (e.g. bilirubin), fatigue, some hair loss (not baldness), increased risk of infection, risk of carcinoid syndrome flare and minor changes in blood production. You should contact your treating doctor if you experience any of these symptoms so they can be managed.
Less common side effects include bone marrow or kidney toxicity. To protect your kidneys, you may receive an infusion of amino acids.4