There are a few types of tumor that fall within a category somewhere between benign and malignant. Carcinoid tumors are the most often occurring of these rare types of midway growths. They have been called "cancers in slow motion" because even though they usually have the potential for ultimately being fatal, they mostly tend to grow slowly so that people afflicted with these tumors usually live for many years, sometimes even for a normal lifetime.
Carcinoid tumors arise from glandular endocrine-hormone producing cells that are widely distributed within the body but found in greatest amounts in the small intestine and then in decreasing amounts in the appendix, rectum, lung, pancreas and very rarely in the ovaries, testes, liver, bile ducts or other locations. The prognosis depends on where the original tumor is located, the likelihood of metastases becoming greater with increasing tumor size.
Carcinoid cells are capable of producing hormones. Those carcinoid tumors that produce large amounts of hormones and other potent chemical substances, and which often have spread to the liver, can cause hot red flushing of the face, diarrhea, and asthma-like wheezing attacks. These episodes of "carcinoid crisis" may be very infrequent at first but gradually occur more often and are usually associated with abrupt low blood pressure and even fainting, although in a few cases the attacks are accompanied by high blood pressure. In many cases the symptoms of Carcinoid Syndrome, resulting from the hormones and chemicals produced, are worse than the symptoms from the growth of the tumor itself.
Not all functioning carcinoid tumors produce the same large variety of chemicals and hormones and it is not yet entirely clear which of the substances are responsible for each of the symptoms. Almost all of these tumors make serotonin and bradykinin.
Non-functioning carcinoid tumors are so slow-growing that many years may pass between the onset of any symptoms and the diagnosis. They can cause intermittent abdominal pain and then a change in bowel habits that may lead to intestinal obstruction. In some cases they cause obscure intestinal bleeding or sometimes don't declare themselves until they cause painful enlargement of the liver due to large deposits of carcinoid metastases that have spread to that organ. The diagnosis is not usually suspected prior to surgery but is then established by biopsy.
Carcinoid Syndrome, due to the presence of a functioning carcinoid tumor, is easily diagnosed when all of the features of the syndrome are present. However, the biggest impediment to making the diagnosis is not thinking of it because of its rarity: when it is considered, just one or two of the main symptoms may be enough to confirm suspicions.
Standard X-ray and imaging techniques can be helpful in finding a carcinoid tumor and identifying its spread. This could include routine chest X-ray, CT scans, MRI, barium enema or upper GI and small bowel X-ray studies. Sometimes upper and lower GI tract endoscopy is also helpful.
A now universally approved (though costly) way of finding carcinoid tumors, as well as other neuroendocrine tumors, is the OctreoScan. It is successful in 85% of carcinoids and consists of a (probably) harmless injection of a minute dose of a short duration radioactive isotope which is specifically attracted to, and concentrated in, carcinoid tumor tissue (and any other neuroendocrine tumor) where it lights up during a radiation scan of the entire body.
There are many conventional treatments for carcinoid tumors and syndrome, although the choice of treatment and their applications can be quite complex. Carcinoid tumors vary greatly in their size, location, symptoms and growth, and therefore the treatment in each case should be individualized to what is best for each particular patient. The wide variety of treatments now available makes the outlook for most victims of the more aggressive carcinoids more hopeful than it used to be.
Surgery is often recommended and can be highly successful. In cases where somewhat larger tumors have spread to local tissues and local lymph nodes but are, along with these locally invaded tissues, still totally surgically removable, the average survival has been 8 years ranging up to 23 years.
Chemotherapy, with many choices available, has been in use since the early 1980s. Radiation is useful only for pain relief and regressing tumors when they have spread to the skeletal system and when they are causing severe pain.
Antihistamines and alpha adrenergic blocking drugs such as Dibenzyline are sometimes used to prevent Carcinoid Syndrome attacks. Certain very severe and prolonged carcinoid crises associated with bronchial (lung) carcinoids or some carcinoids of the stomach are responsive to treatment with corticosteroids (prednisone, Decadron) and Thorazine or Compazine.
Benign: Literally: innocent; not malignant. Often used to refer to cells that are not cancerous.
Bile: A bitter, yellow-green secretion of the liver. Bile is stored in the gallbladder and is released when fat enters the first part of the small intestine (duodenum) in order to aid digestion.
Biopsy: Excision of tissue from a living being for diagnosis.
Calcium: The body's most abundant mineral. Its primary function is to help build and maintain bones and teeth. Calcium is also important to heart health, nerves, muscles and skin. Calcium helps control blood acid-alkaline balance, plays a role in cell division, muscle growth and iron utilization, activates certain enzymes, and helps transport nutrients through cell membranes. Calcium also forms a cellular cement called ground substance that helps hold cells and tissues together.
Chemotherapy: A treatment of disease by any chemicals. Used most often to refer to the chemical treatments used to combat cancer cells.
Congestive: Pertaining to accumulation of blood or fluid within a vessel or organ.
Diarrhea: Excessive discharge of contents of bowel.
Endoscopy: A procedure that uses an Endoscope.
Gastrointestinal: Pertaining to the stomach, small and large intestines, colon, rectum, liver, pancreas, and gallbladder.
Hormones: Chemical substances secreted by a variety of body organs that are carried by the bloodstream and usually influence cells some distance from the source of production. Hormones signal certain enzymes to perform their functions and, in this way, regulate such body functions as blood sugar levels, insulin levels, the menstrual cycle, and growth. These can be prescription, over-the-counter, synthetic or natural agents. Examples include adrenal hormones such as corticosteroids and aldosterone; glucagon, growth hormone, insulin, testosterone, estrogens, progestins, progesterone, DHEA, melatonin, and thyroid hormones such as thyroxine and calcitonin.
Iron: An essential mineral. Prevents anemia: as a constituent of hemoglobin, transports oxygen throughout the body. Virtually all of the oxygen used by cells in the life process are brought to the cells by the hemoglobin of red blood cells. Iron is a small but most vital, component of the hemoglobin in 20,000 billion red blood cells, of which 115 million are formed every minute. Heme iron (from meat) is absorbed 10 times more readily than the ferrous or ferric form.
Lymph Nodes: Small, bean-shaped nodes at various points throughout the body that function to filter the lymph fluid and attempt to destroy the microorganisms and abnormal cells which collect there. The most common locations are the neck (both sides and front), armpit and groin, but also under the jaw and behind the ears. Swollen or painful lymph nodes generally result from localized or systemic infection, abscess formation, or malignancy. Other causes of enlarged lymph nodes are extremely rare. Physical examination for lymph nodes includes pressing on them to check for size, texture, warmth, tenderness and mobility. Most lymph nodes can not be felt until they become swollen, and then will only be tender when pressed or massaged. A lymph node that is painful even without touching indicates greater swelling. Lymph nodes can usually be distinguished from other growths because they generally feel small, smooth, round or oval-shaped and somewhat mobile when attempts are made to push them sideways. Because less fat covers the lymph nodes in children, they are easier to feel, even when they are not busy filtering germs or making antibodies. Children’s nodes enlarge faster, get bigger in response to an infection and stay swollen longer than an adult's.
Magnesium: An essential mineral. The chief function of magnesium is to activate certain enzymes, especially those related to carbohydrate metabolism. Another role is to maintain the electrical potential across nerve and muscle membranes. It is essential for proper heartbeat and nerve transmission. Magnesium controls many cellular functions. It is involved in protein formation, DNA production and function and in the storage and release of energy in ATP. Magnesium is closely related to calcium and phosphorus in body function. The average adult body contains approximately one ounce of magnesium. It is the fifth mineral in abundance within the body--behind calcium, phosphorus, potassium and sodium. Although about 70 percent of the body's magnesium is contained in the teeth and bones, its most important functions are carried out by the remainder which is present in the cells of the soft tissues and in the fluid surrounding those cells.
Malignant: Dangerous. mainly used to describe a cancerous growth -- when used this way, it means the growth is cancerous and predisposed to spreading.
Metabolism: The chemical processes of living cells in which energy is produced in order to replace and repair tissues and maintain a healthy body. Responsible for the production of energy, biosynthesis of important substances, and degradation of various compounds.
Mineral: Plays a vital role in regulating many body functions. They act as catalysts in nerve response, muscle contraction and the metabolism of nutrients in foods. They regulate electrolyte balance and hormonal production, and they strengthen skeletal structures.
MRI: Magnetic Resonance Imaging. A technique used in diagnosis that combines radio waves and magnetic forces to produce detailed images of the internal structures of the body.
Niacin: (Vitamin B-3): A coenzyme B-complex vitamin that assists in the breakdown of carbohydrates, fats and proteins. Essential for the health of the skin, nerves, tongue and digestive system. It is found in every cell of the body and is necessary for energy production. Niacin is also needed for DNA formation.
Potassium: A mineral that serves as an electrolyte and is involved in the balance of fluid within the body. Our bodies contain more than twice as much potassium as sodium (typically 9oz versus 4oz). About 98% of total body potassium is inside our cells. Potassium is the principal cation (positive ion) of the fluid within cells and is important in controlling the activity of the heart, muscles, nervous system and just about every cell in the body. Potassium regulates the water balance and acid-base balance in the blood and tissues. Evidence is showing that potassium is also involved in bone calcification. Potassium is a cofactor in many reactions, especially those involving energy production and muscle building.
Serotonin: A phenolic amine neurotransmitter (C10H12N2O) that is a powerful vasoconstrictor and is found especially in the brain, blood serum and gastric membranes of mammals. Considered essential for relaxation, sleep, and concentration.
Stomach: A hollow, muscular, J-shaped pouch located in the upper part of the abdomen to the left of the midline. The upper end (fundus) is large and dome-shaped; the area just below the fundus is called the body of the stomach. The fundus and the body are often referred to as the cardiac portion of the stomach. The lower (pyloric) portion curves downward and to the right and includes the antrum and the pylorus. The function of the stomach is to begin digestion by physically breaking down food received from the esophagus. The tissues of the stomach wall are composed of three types of muscle fibers: circular, longitudinal and oblique. These fibers create structural elasticity and contractibility, both of which are needed for digestion. The stomach mucosa contains cells which secrete hydrochloric acid and this in turn activates the other gastric enzymes pepsin and rennin. To protect itself from being destroyed by its own enzymes, the stomach’s mucous lining must constantly regenerate itself.
Tryptophan: Essential amino acid. Natural relaxant and sleep aid due to its precursor role in serotonin (a neurotransmitter) synthesis. Along with tyrosine, it is used in the treatment of addictions.