Carcinoid cancer originates from certain hormone producing cells that line several organ systems. It most frequently occurs in the gastrointestinal tract. The exact cause of carcinoid cancer is unknown. It may or may not produce symptoms depending on where in the body it is located. Carcinoid cancer is a slow growing cancer. Carcinoid cancer that is removed before it has spread to other parts of the body is associated with good outcomes.
Carcinoid cancer originates in certain hormone producing cells. Carcinoid tumors are classified as neuroendocrine tumors. They release hormones in response to nerve signals.
Carcinoid tumors can originate in the gastrointestinal tract, respiratory tract, hepatobiliary system, and the reproductive glands. Your gastrointestinal tract consists of your esophagus, stomach, small intestine, and colon. Your respiratory tract is composed of your trachea, bronchi, and lungs. The pancreas, gallbladder, and liver are parts of the hepatobiliary system. The testes in males and the ovaries in females are reproductive glands.
The exact cause of carcinoid cancer is unknown. Cancer occurs when cells grow abnormally and out of control, instead of dividing in an orderly manner. Researchers believe that carcinoid cancer may be linked to a genetic disorder called multiple endocrine neoplasia type 1 (MEN1). Some gastrointestinal conditions appear to increase the risk of carcinoid cancer. Carcinoid cancer in the lungs is not associated with smoking.
Carcinoid cancer develops most frequently in the gastrointestinal tract, particularly in the appendix, rectum, and the lower sections of the small intestine, the jejunum and the ileum. The respiratory tract is the second most common site for carcinoid cancer. The appendix is the most common site for carcinoid cancer in children.
Carcinoid cancer most frequently occurs in people over the age of 50. It is rare in children. The incidence is higher among African Americans. Carcinoid cancer is slightly more common in women than in men.
The symptoms of carcinoid cancer vary depending on where the cancer is located, which hormones are produced by the tumor, and if the cancer has spread from its original site. Cancer that has spread from its original place of development is termed metastasized. Carcinoid cancer in the gastrointestinal tract may not cause symptoms. In some cases, these tumors may cause bowel obstruction resulting in pain, weight loss, constipation, diarrhea, or bleeding.
Carcinoid cancer located in areas other than the gastrointestinal tract or that has metastasized may produce symptoms. Carcinoid cancer may not produce symptoms until it has spread to the liver. A cluster of symptoms, termed carcinoid syndrome, can occur as the tumors overproduce hormones.
Carcinoid syndrome causes a variety of symptoms. It can cause an intense blush or flushing of the face, neck, trunk, back, or legs. The flushing may be accompanied by a rapid heartbeat. Excessive flushing can lead to telangiectasia, reddish spots or veins on the face, chest, or arms. Following flushing, some people experience cyanosis, bluish skin areas caused by a lack of oxygen.
The majority of people with carcinoid syndrome experience diarrhea. Diarrhea may be severe and cause dehydration. You may also experience painful cramping that prevents normal bowel movements. Carcinoid syndrome can cause intestinal blockage, a condition that should be brought to the attention of your doctor, if you are having severe nausea and vomiting along with the inability to have a bowel movement.
Heart valvular lesions are a serious condition that can be caused by carcinoid syndrome. Over 50% of people with carcinoid syndrome experience heart valvular lesions. The efxcess hormones produced by the carcinoid cancer affects the way the heart functions and can lead to carcinoid heart disease. Additionally, heart dysfunction can cause peripheral edema. This condition causes swelling in the ankles, legs, hands, arms, neck, and face. You should contact your doctor if you experience peripheral edema.
Carcinoid syndrome can cause several other symptoms. It can cause your airway passages to constrict and result in wheezing when you breathe. People with carcinoid syndrome tend to develop arthritis more frequently than the general population. Additionally, you may develop pellagra, a skin rash, because of a lack of niacin.
Your doctor can diagnose carcinoid cancer by reviewing your medical history, conducting a physical examination, and administering some tests. Your doctor will test your urine, from a sample that you collect over a 24-hour period. A 5-HIAA test will determine the amount of hormones produced by your body. The hormone levels are usually distinctly high in people with carcinoid cancer. Your blood will be tested for cancer markers, specific substances that are produced in some people with carcinoid cancer. People with carcinoid cancer will also have lower than normal levels of tryptophan in their blood.
A variety of imaging tests may be used to identify the location of carcinoid cancer and determine if it has spread. The most commonly used test is an OctreoScan. Images are taken after the body absorbs a harmless radioactive octreotide. The octreotide is attracted to these types of cancer tumors. The images show where the substance collects and indicates where cancer is located.
Your doctor may order more tests or imaging scans depending on your results and the location of your carcinoid cancer. Your doctor may perform a biopsy. A biopsy entails obtaining a tissue sample to test for cancerous or abnormal cells. In some cases, an exploratory surgery is necessary to locate a carcinoid tumor and determine its size.
If you have carcinoid cancer, your doctor will assign your cancer a classification stage based on the results of all of your tests. Staging describes the cancer and how it has metastasized. Carcinoid cancer can spread to nearby tissues, such as fat, ligaments, muscles, or lymph nodes. It may also spread to distant sites including the liver, bones, and lungs. Staging is helpful for treatment planning and recovery prediction.
There is more than one type of staging system for cancer, and you should make sure that you and your doctor are referring to the same one. Generally, lower numbers in a classification system indicate a less serious cancer, and higher numbers indicate a more serious cancer. The stages may be subdivided into grades or classifications that use letters and numbers.
Treatment of carcinoid cancer is individualized and depends on many factors including the stage of the cancer, the cancer cell type, and the location of the cancer. Surgery to remove the cancer is the most common treatment and can result in a cure. There are several different types of surgery to remove carcinoid cancer and several different procedures to remove metastasized cancer.
Carcinoid tumors in the appendix may require appendectomy and surgical bowel resection. Carcinoid tumors in the rectum may be treated with electric fulguration (cauterizing or “burning”), local excision, or resection. Surgical resection may be required for carcinoid tumors in the stomach, colon, and pancreas. Small intestine tumors may be removed with local excision and resection. Depending on the condition, it may be necessary to remove nearby lymph nodes. Minimally invasive laparoscopic surgeries are used when possible. Minimally invasive surgeries are associated with quicker recovery times. In rare cases, liver transplantation may be used for select individuals with metastasized liver cancer.
Chemotherapy, radiation, and immunotherapy may be used with surgery to treat or relieve symptoms of carcinoid cancer. Chemotherapy uses drugs to destroy cancer cells. There are different types of chemotherapy, and the drugs are usually given in cycles over time. Radiation uses high-energy X-rays to kill cancer cells. Immunotherapy uses biological agents to boost the body’s immune system to fight cancer cells.
The experience of carcinoid cancer and cancer treatments can be an emotional one for people with cancer and their loved ones. It is important that you receive support. Some people find comfort in their family, friends, co-workers, counselors, and faith. Cancer support groups are another good option. They can be a source of information and support from people who understand what you are experiencing. Ask your doctor for cancer support groups in your area.
Because the exact cause of carcinoid cancer is unknown, there is no known way to prevent carcinoid cancer.
Risk factors may increase your likelihood of developing carcinoid cancer, although some people that experience this cancer may not have any risk factors. People with all of the risk factors may never develop carcinoid cancer; however, the likelihood increases with the more risk factors you have. You should tell your doctor about your risk factors and discuss your concerns.
Risk factors for carcinoid cancer:
Some cases of carcinoid cancer can cause serious complications including intestinal blockage and cardiac problems that can lead to heart failure. Although carcinoid cancer is a slow growing type of cancer, it can spread to distant sites including the liver, lungs, bone, and lymph nodes. Metastasized liver cancer is associated with poor outcomes. Further, people with carcinoid cancer are at risk for other conditions caused by excess hormone production including Cushing’s Syndrome and somatostatinoma.
Researchers are attempting to determine the causes of carcinoid cancer. They are trying to find new methods to diagnose and treat this cancer. New chemotherapy drugs and types of radiation to fight cancer are being tested. Further, new drugs are being studied to relieve the symptoms of carcinoid syndrome.