Source: National Cancer Institute Research, www.cancer.gov
The gastrointestinal (GI) tract is part of the body's digestive system. It helps to digest food, takes nutrients (vitamins, minerals, carbohydrates, fats, proteins, and water) from food to be used by the body and helps pass waste material out of the body. The GI tract is made up of these and other organs:
Gastrointestinal carcinoid tumors form from a certain type of neuroendocrinecell (a type of cell that is like a nerve cell and a hormone-making cell). These cells are scattered throughout the chest and abdomen but most are found in the GI tract. Neuroendocrine cells make hormones that help control digestive juices and the muscles used in moving food through the stomach and intestines. A GI carcinoid tumor may also make hormones and release them into the body.
GI carcinoid tumors are rare and most grow very slowly. Most of them occur in the small intestine, rectum, and appendix. Sometimes more than one tumor will form.
See the following PDQ summaries for more information related to GI and other types of carcinoid tumors:
Anything that increases a person's chance of developing 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 to your doctor if you think you may be at risk.
Risk factors for GI carcinoid tumors include the following:
Signs and symptoms may be caused by the growth of the tumor and/or the hormones the tumor makes. Some tumors, especially tumors of the stomach or appendix, may not cause signs or symptoms. Carcinoid tumors are often found during tests or treatments for other conditions.
Carcinoid tumors in the small intestine (duodenum, jejunum, and ileum), colon, and rectum sometimes cause signs or symptoms as they grow or because of the hormones they make. Other conditions may cause the same signs or symptoms. Check with your doctor if you have any of the following:
Signs and symptoms of GI carcinoid tumors in the duodenum (first part of the small intestine, that connects to the stomach) may include the following:
Signs and symptoms of GI carcinoid tumors in the jejunum (middle part of the small intestine) and ileum (last part of the small intestine, that connects to the colon) may include the following:
Signs and symptoms of GI carcinoid tumors in the colon may include the following:
Signs and symptoms of GI carcinoid tumors in the rectum may include the following:
The hormones made by gastrointestinal carcinoid tumors are usually destroyed by liverenzymes in the blood. If the tumor has spread to the liver and the liver enzymes cannot destroy the extra hormones made by the tumor, high amounts of these hormones may remain in the body and cause carcinoid syndrome. This can also happen if tumor cells enter the blood. Signs and symptoms of carcinoid syndrome include the following:
These signs and symptoms may be caused by gastrointestinal carcinoid tumors or by other conditions. Talk to your doctor if you have any of these signs or symptoms.
The following tests and procedures may be used:
The prognosis (chance of recovery) and treatment options depend on the following:
Staging is the process used to find out how far the cancer has spread. The information gathered from the staging process determines the stage of the disease. The results of tests and procedures used to diagnosegastrointestinal (GI) carcinoid tumors may also be used for staging. See the General Information section for a description of these tests and procedures. A bone scan may be done to check if there are rapidly dividing cells, such as cancer cells, in the bone. A very small amount of radioactive material is injected into a vein and travels through the bloodstream. The radioactive material collects in the bones and is detected by a scanner.
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 gastrointestinal (GI) carcinoid tumor spreads to the liver, the tumor cells in the liver are actually GI carcinoid tumor cells. The disease is metastatic GI carcinoid tumor, not liver cancer.
For many cancers it is important to know the stage of the cancer in order to plan treatment. However, the treatment of gastrointestinal carcinoid tumors is not based on the stage of the cancer. Treatment depends mainly on whether the tumor can be removed by surgery and if the tumor has spread.
Treatment is based on whether the tumor:
Different types of treatment are available for patients with gastrointestinal carcinoid tumor. 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.
Treatment of GI carcinoid tumors usually includes surgery. One of the following surgical procedures may be used:
Radiation therapy is a cancer treatment that uses high-energy x-rays or other types of radiation to kill cancer cells. There are two types of radiation therapy. External radiation therapy uses a machine outside the body to send radiation toward the cancer. Internal radiation therapy uses a radioactive substance sealed in needles, seeds, wires, or catheters that are placed directly into or near the cancer. The way the radiation therapy is given depends on the type and stage of the cancer being treated.
Radiopharmaceutical therapy is a type of radiation therapy. Radiation is given to the tumor using a drug that has a radioactive substance, such as iodine I 131, attached to it. The radioactive substance kills the tumor cells.
Chemotherapy is a cancer treatment that uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping the cells 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).
Chemoembolization of the hepatic artery is a type of regional chemotherapy that may be used to treat a gastrointestinal carcinoid tumor that has spread to the liver. The anticancer drug is injected into the hepatic artery through a catheter (thin tube). The drug is mixed with a substance that embolizes (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. 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.
The way the chemotherapy is given depends on the type and stage of the cancer being treated.
Hormone therapy with a somatostatin analogue is a treatment that stops extra hormones from being made. GI carcinoid tumors are treated with octreotide or lanreotide which are injected under the skin or into the muscle. Octreotide and lanreotide may also have a small effect on stopping tumor growth.
Treatment of carcinoid syndrome may include the following:
Other ways to help treat carcinoid syndrome include avoiding things that cause flushing or difficulty breathing such as alcohol, nuts, certain cheeses and foods with capsaicin, such as chili peppers. Avoiding stressful situations and certain types of physical activity can also help treat carcinoid syndrome.
For some patients with carcinoid heart syndrome, a heart valve replacement may be done.
This summary section describes treatments that are being studied in clinical trials. It may not mention every new treatment being studied. Information about clinical trials is available from the NCI Web site.
Targeted therapy is a type of treatment that uses drugs or other substances to identify and attack specific cancer cells without harming normal cells. Several types of targeted therapy are being studied in the treatment of GI carcinoid tumors.
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. See the Treatment Options section that follows for links to current treatment clinical trials. These have been retrieved from NCI's listing of clinical trials.
Some of the tests that were done to diagnose the cancer or to find out the stage of the cancer may be repeated. Some tests will be repeated in order 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. This is sometimes called re-staging.
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). These tests are sometimes called follow-up tests or check-ups.
Treatment of gastrointestinal (GI) carcinoid tumors in the stomach may include the following:
For patients with GI carcinoid tumors in the stomach and MEN1 syndrome, treatment may also include:
Check for U.S. clinical trials from NCI's list of cancer clinical trials that are now accepting patients with localized gastrointestinal carcinoid tumor and regional gastrointestinal carcinoid tumor. For more specific results, refine the search by using other search features, such as the location of the trial, the type of treatment, or the name of the drug. Talk with your doctor about clinical trials that may be right for you. General information about clinical trials is available from the NCI Web site.
It is not clear what the best treatment is for GI carcinoid tumors in the duodenum (first part of the small intestine, that connects to the stomach). Treatment may include the following:
Treatment of GI carcinoid tumors in the jejunum (middle part of the small intestine) and ileum (last part of the small intestine, that connects to the colon) may include the following:
Check for U.S. clinical trials from NCI's list of cancer clinical trials that are now accepting patients with localized gastrointestinal carcinoid tumor and regional gastrointestinal carcinoid tumor. For more specific results, refine the search by using other search features, such as the location of the trial, the type of treatment, or the name of the drug. Talk with your doctor about clinical trials that may be right for you. General information about clinical trials is available from the NCI Web site.
Treatment of GI carcinoid tumors in the appendix may include the following:
Check for U.S. clinical trials from NCI's list of cancer clinical trials that are now accepting patients with localized gastrointestinal carcinoid tumor and regional gastrointestinal carcinoid tumor. For more specific results, refine the search by using other search features, such as the location of the trial, the type of treatment, or the name of the drug. Talk with your doctor about clinical trials that may be right for you. General information about clinical trials is available from the NCI Web site.
Treatment of GI carcinoid tumors in the colon may include the following:
Check for U.S. clinical trials from NCI's list of cancer clinical trials that are now accepting patients with localized gastrointestinal carcinoid tumor and regional gastrointestinal carcinoid tumor. For more specific results, refine the search by using other search features, such as the location of the trial, the type of treatment, or the name of the drug. Talk with your doctor about clinical trials that may be right for you. General information about clinical trials is available from the NCI Web site.
Treatment of GI carcinoid tumors in the rectum may include the following:
It is not clear what the best treatment is for tumors that are 1 to 2 centimeters. Treatment may include the following:
Check for U.S. clinical trials from NCI's list of cancer clinical trials that are now accepting patients with localized gastrointestinal carcinoid tumor and regional gastrointestinal carcinoid tumor. For more specific results, refine the search by using other search features, such as the location of the trial, the type of treatment, or the name of the drug. Talk with your doctor about clinical trials that may be right for you. General information about clinical trials is available from the NCI Web site.
Distant metastases
Treatment of distant metastases of GI carcinoid tumors is usually palliative therapy to relieve symptoms and improve quality of life. Treatment may include the following:
Liver metastases
Treatment of cancer that has spread to the liver may include the following:
Check for U.S. clinical trials from NCI's list of cancer clinical trials that are now accepting patients with metastatic gastrointestinal carcinoid tumor. For more specific results, refine the search by using other search features, such as the location of the trial, the type of treatment, or the name of the drug. Talk with your doctor about clinical trials that may be right for you. General information about clinical trials is available from the NCI Web site.
Treatment of recurrentGI carcinoid tumors may include the following:
Check for U.S. clinical trials from NCI's list of cancer clinical trials that are now accepting patients with recurrent gastrointestinal carcinoid tumor. For more specific results, refine the search by using other search features, such as the location of the trial, the type of treatment, or the name of the drug. Talk with your doctor about clinical trials that may be right for you. General information about clinical trials is available from the NCI Web site.
For more information from the National Cancer Institute about gastrointestinal carcinoid tumors, see the following:
For general cancer information and other resources from the National Cancer Institute, see the following: