The pancreas is a gland about 6 inches long that is shaped like a thin pear lying on its side. The wider end of the pancreas is called the head, the middle section is called the body, and the narrow end is called the tail. The pancreas lies behind the stomach and in front of the spine.
There are two kinds of cells in the pancreas:
This summary discusses islet cell tumors of the endocrine pancreas. See the PDQ summary on Pancreatic Cancer Treatment for information on exocrine pancreatic cancer.
Pancreatic neuroendocrine tumors (NETs) may be benign (not cancer) or malignant (cancer). When pancreatic NETs are malignant, they are called pancreatic endocrine cancer or islet cell carcinoma.
Pancreatic NETs are much less common than pancreatic exocrine tumors and have a better prognosis.
Pancreatic NETs may be functional or nonfunctional:
Most pancreatic NETs are functional tumors.
Pancreatic NETs make different kinds of hormones such as gastrin, insulin, and glucagon. Functional pancreatic NETs include the following:
Anything that increases your risk of getting a disease is called a risk factor. Having a risk factor does not mean that you will get cancer; not having risk factors doesn't mean that you will not get cancer. Talk with your doctor if you think you may be at risk.
Multiple endocrine neoplasia type 1 (MEN1) syndrome is a risk factor for pancreatic NETs.
Signs or symptoms can be caused by the growth of the tumor and/or by hormones the tumor makes or by other conditions. Some tumors may not cause signs or symptoms. Check with your doctor if you have any of these problems.
Signs and symptoms of a non-functional pancreatic NET
A non-functional pancreatic NET may grow for a long time without causing signs or symptoms. It may grow large or spread to other parts of the body before it causes signs or symptoms, such as:
Signs and symptoms of a functional pancreatic NET
The signs and symptoms of a functional pancreatic NET depend on the type of hormone being made.
Too much gastrin may cause:
Too much insulin may cause:
Too much glucagon may cause:
Too much vasoactive intestinal peptide (VIP) may cause:
Too much somatostatin may cause:
A pancreatic NET may also make too much adrenocorticotropic hormone (ACTH) and cause Cushing syndrome. Signs and symptoms of Cushing syndrome include the following:
The treatment of pancreatic NETs that make too much ACTH and Cushing syndrome are not discussed in this summary.
The following tests and procedures may be used:
The following tests and procedures may be used:
Gastrinoma
Insulinoma
Glucagonoma
Other tumor types
Pancreatic NETs can often be cured. The prognosis and treatment options depend on the following:
The process used to find out if cancer has spread within the pancreas or to other parts of the body is called staging. The results of the tests and procedures used to diagnose pancreatic neuroendocrine tumors (NETs) are also used to find out whether the cancer has spread. See the General Information section for a description of these tests and procedures.
Although there is a standard staging system for pancreatic NETs, it is not used to plan treatment. Treatment of pancreatic NETs is based on the following:
Cancer can spread through tissue, the lymph system, and the blood:
When cancer spreads to another part of the body, it is called metastasis. Cancer cells break away from where they began (the primary tumor) and travel through the lymph system or blood.
The metastatic tumor is the same type of tumor as the primary tumor. For example, if a pancreatic neuroendocrine tumor spreads to the liver, the tumor cells in the liver are actually neuroendocrine tumor cells. The disease is metastatic pancreatic neuroendocrine tumor, not liver cancer.
The tumors may come back in the pancreas or in other parts of the body.
Different types of treatments are available for patients with pancreatic neuroendocrine tumors (NETs). Some treatments are standard (the currently used treatment), and some are being tested in clinical trials. A treatment clinical trial is a research study meant to help improve current treatments or obtain information on new treatments for patients with cancer. When clinical trials show that a new treatment is better than the standard treatment, the new treatment may become the standard treatment. Patients may want to think about taking part in a clinical trial. Some clinical trials are open only to patients who have not started treatment.
An operation may be done to remove the tumor. One of the following types of surgery may be used:
Chemotherapy is a cancer treatment that uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing. When chemotherapy is taken by mouth or injected into a vein or muscle, the drugs enter the bloodstream and can reach cancer cells throughout the body (systemic chemotherapy). When chemotherapy is placed directly into the cerebrospinal fluid, an organ, or a body cavity such as the abdomen, the drugs mainly affect cancer cells in those areas (regional chemotherapy). Combination chemotherapy is the use of more than one anticancer drug. The way the chemotherapy is given depends on the type of the cancer being treated.
Hormone therapy is a cancer treatment that removes hormones or blocks their action and stops cancer cells from growing. Hormones are substances made by glands in the body and circulated in the bloodstream. Some hormones can cause certain cancers to grow. If tests show that the cancer cells have places where hormones can attach (receptors), drugs, surgery, or radiation therapy is used to reduce the production of hormones or block them from working.
Hepatic arterial occlusion uses drugs, small particles, or other agents to block or reduce the flow of blood to the liver through the hepatic artery (the major blood vessel that carries blood to the liver). This is done to kill cancer cells growing in the liver. The tumor is prevented from getting the oxygen and nutrients it needs to grow. The liver continues to receive blood from the hepatic portal vein, which carries blood from the stomach and intestine.
Chemotherapy delivered during hepatic arterial occlusion is called chemoembolization. The anticancer drug is injected into the hepatic artery through a catheter (thin tube). The drug is mixed with the substance that blocks the artery and cuts off blood flow to the tumor. Most of the anticancer drug is trapped near the tumor and only a small amount of the drug reaches other parts of the body.
The blockage may be temporary or permanent, depending on the substance used to block the artery.
Targeted therapy is a type of treatment that uses drugs or other substances to identify and attack specific cancer cells. Targeted therapies usually cause less harm to normal cells than chemotherapy or radiation therapy do. Certain types of targeted therapies are being studied in the treatment of pancreatic NETs.
Supportive care is given to lessen the problems caused by the disease or its treatment. Supportive care for pancreatic NETs may include treatment for the following:
Information about clinical trials is available from the NCI website.
For information about side effects caused by treatment for cancer, visit our Side Effects page.
For some patients, taking part in a clinical trial may be the best treatment choice. Clinical trials are part of the cancer research process. Clinical trials are done to find out if new cancer treatments are safe and effective or better than the standard treatment.
Many of today's standard treatments for cancer are based on earlier clinical trials. Patients who take part in a clinical trial may receive the standard treatment or be among the first to receive a new treatment.
Patients who take part in clinical trials also help improve the way cancer will be treated in the future. Even when clinical trials do not lead to effective new treatments, they often answer important questions and help move research forward.
Some clinical trials only include patients who have not yet received treatment. Other trials test treatments for patients whose cancer has not gotten better. There are also clinical trials that test new ways to stop cancer from recurring (coming back) or reduce the side effects of cancer treatment.
Clinical trials are taking place in many parts of the country. Information about clinical trials supported by NCI can be found on NCI’s clinical trials search webpage. Clinical trials supported by other organizations can be found on the ClinicalTrials.gov website.
As you go through treatment, you will have follow-up tests or check-ups. Some tests that were done to diagnose or stage the cancer may be repeated to see how well the treatment is working. Decisions about whether to continue, change, or stop treatment may be based on the results of these tests.
Some of the tests will continue to be done from time to time after treatment has ended. The results of these tests can show if your condition has changed or if the cancer has recurred (come back).
For information about the treatments listed below, see the Treatment Option Overview section.
Treatment of gastrinoma may include supportive care and the following:
Use our clinical trial search to find NCI-supported cancer clinical trials that are accepting patients. You can search for trials based on the type of cancer, the age of the patient, and where the trials are being done. General information about clinical trials is also available.
For information about the treatments listed below, see the Treatment Option Overview section.
Treatment of insulinoma may include the following:
Use our clinical trial search to find NCI-supported cancer clinical trials that are accepting patients. You can search for trials based on the type of cancer, the age of the patient, and where the trials are being done. General information about clinical trials is also available.
For information about the treatments listed below, see the Treatment Option Overview section.
Treatment may include the following:
Use our clinical trial search to find NCI-supported cancer clinical trials that are accepting patients. You can search for trials based on the type of cancer, the age of the patient, and where the trials are being done. General information about clinical trials is also available.
For information about the treatments listed below, see the Treatment Option Overview section.
For VIPoma, treatment may include the following:
For somatostatinoma, treatment may include the following:
Treatment of other types of pancreatic neuroendocrine tumors (NETs) may include the following:
Use our clinical trial search to find NCI-supported cancer clinical trials that are accepting patients. You can search for trials based on the type of cancer, the age of the patient, and where the trials are being done. General information about clinical trials is also available.
For information about the treatments listed below, see the Treatment Option Overview section.
Treatment of pancreatic neuroendocrine tumors (NETs) that continue to grow during treatment or recur (come back) may include the following:
For more information from the National Cancer Institute about pancreatic neuroendocrine tumors (NETs), see the following:
For general cancer information and other resources from the National Cancer Institute, visit:
Use our clinical trial search to find NCI-supported cancer clinical trials that are accepting patients. You can search for trials based on the type of cancer, the age of the patient, and where the trials are being done. General information about clinical trials is also available.
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PDQ® Adult Treatment Editorial Board. PDQ Pancreatic Neuroendocrine Tumors (Islet Cell Tumors) Treatment. Bethesda, MD: National Cancer Institute. Updated <MM/DD/YYYY>. Available at: https://www.cancer.gov/types/pancreatic/patient/pnet-treatment-pdq. Accessed <MM/DD/YYYY>. [PMID: 26389340]
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