What is carcinoid syndrome

Carcinoid syndrome is a group of symptoms associated with carcinoid tumors ¹. Carcinoid tumors are neuroendocrine tumors of the small intestine, colon, appendix, and bronchial tubes in the lungs. Carcinoid syndrome is the term applied to a group of symptoms mediated by various substances produced by some carcinoid tumors. Carcinoid syndrome occurs in very few people with carcinoid tumors, after the tumor has spread to the liver or lung.

Carcinoid syndrome symptoms

Symptoms commonly experienced in carcinoid syndrome are:

• Flushing (face, neck, or upper chest), such as widened blood vessels seen on the skin (telangiectasias);
• Diarrhea;
• Difficulty breathing, such as wheezing or asthma;
• Heart problems, such as leaking heart valves, slow heartbeat, low or high blood pressure, heart palpitations;
• Heart failure due to valve problems may also occur;
• Abdominal pain and cramping;
• Arthritis;
• Niacin deficiency;
• Swelling of the feet.

Sometimes symptoms are brought on by physical exertion, or eating or drinking things such as blue cheese, chocolate, or red wine.

Carcinoid Syndrome occurs in approximately 10% of all individuals diagnosed with carcinoid tumor and can lead to right-sided heart failure. Carcinoid Syndrome is most common in individuals with liver metastases from ileal carcinoid tumors.

The main biologically active peptides secreted in carcinoid syndrome are serotonin and possibly tachykinins, motilin, prostaglandins. The hormones cause the blood vessels to open (dilate). This causes carcinoid syndrome.

Individuals with Carcinoid Syndrome can also experience carcinoid crisis which can occur spontaneously or be stress induced. A Carcinoid Crisis can be a life-threatening event that requires careful monitoring.

Symptoms of a Carcinoid Crisis may include:

• Severe hypotension or hypertension,
• Irregular and/or rapid heartbeat,
• Wheezing,
• Prolonged flushing,
• Severe dyspnea (shortness of breath), and
• Peripheral cyanosis (lack of oxygenated blood).

Carcinoid syndrome is relatively rare. The number of new cases per year is 0.5–2.0 per 1,000,000 population. It occurs in approximately 10% of patients with small bowel carcinoid tumor. Less than 1% of carcinoid tumors in the appendix are associated with carcinoid syndrome. Among patients with carcinoid syndrome, a large proportion (75-80%) has small bowel carcinoids.

Causes of Carcinoid syndrome

Carcinoid syndrome is caused by a carcinoid tumor that secretes serotonin or other chemicals into your bloodstream. Carcinoid tumors occur most commonly in your gastrointestinal tract, including your stomach, small intestine, appendix, colon and rectum, or in your lungs.

Only a small percentage of carcinoid tumors secrete the chemicals that cause carcinoid syndrome. In most cases, the liver effectively neutralizes the chemicals before they have a chance to travel through your body and cause symptoms.

However, when an advanced tumor spreads (metastasizes) to the liver itself, these tumors may secrete chemicals that aren’t neutralized before reaching the bloodstream. Most people who experience carcinoid syndrome have an advanced cancer that has spread to the liver.

Some carcinoid tumors don’t have to be advanced to cause carcinoid syndrome. For instance, carcinoid lung tumors that secrete chemicals into the blood do so farther upstream from the liver — not directly into the liver, where the chemicals are processed and eliminated.

Carcinoid tumors in the intestine, on the other hand, secrete their chemicals into blood that must first pass through the liver before reaching the rest of the body. The liver usually neutralizes the chemicals before they can affect the rest of the body.

What causes carcinoid tumors is unclear.

Carcinoid syndrome complications

Having carcinoid syndrome can cause the following complications:

Carcinoid heart disease. Some people with carcinoid syndrome develop carcinoid heart disease. Carcinoid syndrome causes a thickening of the heart valves, making it difficult for them to function properly. As a result, the heart valves may leak.

Signs and symptoms of carcinoid heart disease include fatigue and shortness of breath during physical activity. Carcinoid heart disease can eventually lead to heart failure.

Your doctor may recommend medications for your heart. Surgical repair of damaged heart valves may be an option in advanced carcinoid heart disease.

Bowel obstruction. Cancer that spreads to the lymph nodes next to your small intestine can cause narrowing and kinking of your intestine, leading to a bowel obstruction.

Signs and symptoms of a bowel obstruction include severe, cramping abdominal pain and vomiting. Surgery may be necessary to relieve the obstruction.

Carcinoid crisis. Carcinoid crisis causes a severe episode of flushing, low blood pressure, confusion and breathing difficulty.

Carcinoid crisis can occur in people with carcinoid tumors when they are exposed to certain triggers, including anesthesia used during surgery. Carcinoid crisis can be fatal. Your doctor may give you medications before surgery to reduce the risk of carcinoid crisis.

What is a carcinoid tumor

Carcinoid tumors are neuroendocrine tumors, which are tumors that originate from the neuroendocrine cells that secrete regulatory hormones and are present in the nervous and endocrine/hormonal system. These neuroendocrine cells, which have features like nerve cells and hormone-producing cells, release hormones into the blood in response to signals from the nervous system. Carcinoid tumors commonly refers to neuroendocrine tumors that originate in the gastrointestinal (GI) tract, lungs, appendix and thymus, although they can also occur in the lymph nodes, brain, bone, gonads (ovaries and testes) and skin. Carcinoid tumors are usually indolent (slow-growing) by nature and develop over the course of many years. However, aggressive, fast-growing forms of carcinoid cancer also exist.

Most primary carcinoid tumors arise from enterochromaffin cells of the gastrointestinal/digestive tract, with the most common sites being the appendix, small bowel and rectum. They can also be seen in the liver, pancreas, bronchus (branch of the windpipe into the lung), and ovaries.

Carcinoid tumors can be classified based on the primitive gut that gives rise to the tumor (i.e. foregut, midgut, hindgut). Examples of foregut carcinoid tumors are carcinoids of the bronchus, stomach, beginning portion of the small bowel (proximal part of duodenum) and pancreas. Midgut tumors are derived from the rest of the small bowel (second portion of duodenum, jejunum, ileum), and part of the large bowel (right colon). These are the most common type of carcinoid tumors in adults. Hindgut carcinoid tumors include those of the large bowel (transverse colon, descending colon, and rectum).

Carcinoid tumors can secrete a variety of functional hormones and chemicals although not all carcinoid tumors do. Carcinoid tumors produce, store, and release a variety of hormones and other substances (polypeptides, biogenic amines, and prostaglandins). Amines produced include serotonin, 5-hydroxytryptophan, norepinephrine, chromogranin A, histamine, dopamine, pancreatic polypeptide and gastrin. Examples of polypeptides produced are kallikrein, bradykynin, somatostatin, neuropeptide K, neurokinin A, ACTH, growth hormone, glucagon, etc.

Carcinoid tumors are referred to as functioning if they secrete hormones that cause a clinical syndrome.

Functioning carcinoid tumors that occur in the digestive tract and pancreas release the substances they produce directly into the hepatic portal vein (a blood vessel in the abdominal cavity) which carries them directly to the liver where they are metabolized (broken down). Since the liver metabolizes these substances, their message is not sent to the rest of the body. Consequently, tumors of the digestive tract and pancreas are not usually detected until they have metastasized to the liver or cause obstructive symptoms.

When carcinoid metastasizes to the liver, the liver is not always able to metabolize all of the hormones secreted. This excess of hormone called hypersecretion can cause an array of symptoms called carcinoid syndrome.

In intestinal carcinoid tumors, the occurrence of carcinoid syndrome usually implies liver involvement.

Carcinoids that occur in areas outside of the intestine and pancreas such as the lung and stomach do not release their hormones into the hepatic portal vein but release them directly into the bloodstream, bypassing the liver. Consequently, individuals with carcinoid tumor in these locations can sometimes develop carcinoid syndrome without liver metastases as well as other symptoms and syndromes.

Carcinoid tumors are rare. In the United States, there were about 13,000 cases identified from 1950 to 1999. The estimated occurrence rate is 2.0/100,000 for men and 2.4/100,000 for women and that there are over 100,000 people currently living with neuroendocrine tumors within the United States. The tumor is most common among African males. The age range at which the tumor occurs is between the second and the ninth decade. About 67% of cases occur in the digestive tract while another 25% occur in the airway and lungs.

Furthermore, for reasons not well understood, the incidence of carcinoid tumor is rising. Since most individuals with carcinoid are asymptomatic until the tumors metastasize, the average time between tumor development and diagnosis is between 5 to 10 years. Survival rates for individuals with carcinoid vary and depend on tumor type, location, extent of metastases, and many other factors. Currently, surgery is the only cure for localized tumors (those which have not spread) and there is no cure for metastatic carcinoid.

When carcinoid tumors happen alone (without carcinoid syndrome), diagnosis is often delayed due to the vagueness of symptoms. Carcinoids in the duodenum (first part of small bowel), stomach and rectum are most frequently found by chance at endoscopy (a procedure involving passing a tube with a camera through the mouth or the bottom end to look at the digestive tract). Those in the appendix are almost always found incidentally during surgery.

Carcinoid tumors are slow-growing. About one in nine patients with carcinoid have distant spread to other organs (metastasis) when carcinoid tumor is diagnosed. Metastasis at diagnosis is most common in small bowel and large bowel carcinoids, whereas carcinoids in the rectum, airway and stomach are less likely to spread.

In the majority (about 90%) of cases, carcinoid syndrome occurs after distant spread to the liver. There are, however, exceptions, for example carcinoids in the airway or ovaries, where carcinoid syndrome can rarely happen without liver involvement.

Carcinoid tumor locations and classifications

Carcinoid tumors can develop almost anywhere in the body. Carcinoid tumors can be classified by location, histology and biological activity in the following way:

Embryonic Gut Derivation

Foregut Carcinoid Tumors

Located in the lungs, thymus, stomach, first part of the duodenum (small intestine), or the pancreas.

Gastric Carcinoids (carcinoids of the stomach) are further classified as:

• Type 1: Associated with chronic atrophic gastritis (inflammation of the stomach lining) caused by hypergastrinemia (high levels of the hormone gastrin).
• Type 2: Implicated with Zollinger Ellison Syndrome and MultipleEndocrine Neoplasia Type 1 (MEN-1).
• Type 3: Sporadic, not associated with hypergastrinemia, can cause Atypical Carcinoid S yndrome and are frequently malignant.

Carcinoid tumor lung (pulmonary carcinoids) are further classified as:

• Typical Pulmonary Carcinoids (benign or low-grade malignant): Considered to be well-differentiated, commonly located in the center of the lungs, and rarely metastasize ².
• Atypical Pulmonary Carcinoids (low-grade malignant): Poorly differentiated, commonly located in the periphery of lungs, characterized by frequent mitoses (cellular division), and frequently metastasize ².

Midgut Carcinoid Tumors

Located in the small intestine, appendix, or right colon (large intestine).

Hindgut Carcinoid Tumors

Located in the transverse colon, sigmoid colon, or rectum.

Presence of Clinical Syndrome

Functioning

A functioning carcinoid tumor secretes biochemically active substances such as hormones, which cause specific clinical syndromes such as Carcinoid Syndrome or Zollinger-Ellison syndrome.

Non-functioning

A non-functioning carcinoid tumor secretes specific substances but these substances are either inactive and/or do not cause any clinical syndrome.

Inherited Versus Sporadic

Sporadic

Cancer causing mutations arise randomly.

Inherited

Cancer causing mutations are inherited due to MEN-1 or other familial factors.

Carcinoid tumors can be familial or sporadic. Inherited carcinoid cancer refers to carcinoid cancer which is genetically inherited whereas sporadic carcinoid cancer has no hereditary basis. Carcinoid tumors are generally thought to be sporadic, except for a small proportion of which occur as a part of MEN (multiple endocrine neoplasia) syndromes ³. Other familial factors contribute to a small proportion of carcinoid tumors; these are less understood than MEN-1 causes.

What causes carcinoid tumors?

It’s not known exactly why carcinoid tumors develop, but it’s thought that most occur by chance.

Your chances of developing a carcinoid tumor may be increased if you have:

• a rare family syndrome called multiple endocrine neoplasia type 1 (MEN1)
• parents or siblings with a carcinoid tumor
• parents with squamous cell skin cancer, non-Hodgkin’s lymphoma, or cancer of the brain, breast, liver, womb, bladder or kidney
• conditions called neurofibromatosis or tuberous sclerosis

Risk Factors for developing carcinoid tumor

The cause if virtually unknown. Factors that are associated with an increased occurrence of carcinoid tumor are:

• A family history of carcinoid in a first-degree relative (3.6 times the risk);
• A well-educated social background (2.8 times the risk);
• Birth in a large city (1.39 times the risk).

Genetic influences are suspected. Reported genetic abnormalities include changes in the chromosome.

Carcinoid tumor survival rate

If the whole tumor can be removed, this may cure the cancer and symptoms altogether. But even if surgeons cannot remove the entire tumor, it usually grows slowly and can be controlled with medication.

The survival rate at 5 years following diagnosis (5-year survival rate) for all carcinoid tumors, regardless of the site of tumor, is 67%. Many people remain relatively well and lead active lives, with only occasional symptoms. The potential for distant spread to other organs and the probability of the disease reoccurring correlate with the size and site of the tumor. A tumor less than 2 cm in diameter carries a better disease outcome. Carcinoid tumors that occur in the rectum have the best 5-year survival rate of more than 80%. Tumors in the airway, lungs and appendix also have 5-year survival of more than 70%.

Unfortunately, life expectancy is not as good for cancer that has spread to other parts of your body, because it won’t usually be possible to remove all of it. However, treatment can still control your symptoms and slow down the spread of cancer. The presence of the carcinoid syndrome confers a poorer survival rate, ranging from less than one year to 38 months.

Carcinoid tumor symptoms

Carcinoid tumors can cause life-threatening symptoms from both hormone hypersecretion (over production) as well as tumor growth and invasion. The majority of individuals with carcinoid tumors are asymptomatic until the tumors metastasize to the liver and cause symptoms of tumor secretion. However, as the tumors grow they can cause obstructive symptoms.

The signs and symptoms of carcinoid syndrome depend on which chemicals the carcinoid tumor secretes into your bloodstream. The most common signs and symptoms of carcinoid syndrome include:

• Skin flushing. The skin on your face and upper chest feels hot and changes color — ranging from pink to purple. Flushing episodes may last from a few minutes to a few hours or longer. Flushing may happen for no obvious reason, though sometimes it can be triggered by stress, exercise or drinking alcohol.
• Facial skin lesions. Purplish areas of spiderlike veins may appear on the nose and upper lip.
• Diarrhea. Frequent, watery stools sometimes accompanied by abdominal cramps may occur in people who have carcinoid syndrome.
• Difficulty breathing. Asthma-like signs and symptoms, such as wheezing and shortness of breath, may occur at the same time you experience skin flushing.
• Rapid heartbeat. Periods of a fast heart rate could be a sign of carcinoid syndrome.

Typical Carcinoid Syndrome is the most common form of Carcinoid Syndrome and is most often caused by midgut carcinoids that have metastasized to the liver. Excess serotonin is the hormone most frequently related to Carcinoid Syndrome. The syndrome is characterized by brief episodes of flushing, diarrhea, cough, wheezing, shortness of breath, heart disease, and in rare cases, pellagra. Flushing and diarrhea are the two main symptoms that are associated with Carcinoid Syndrome. Diarrhea can be mild to severe which may lead to weight loss and life style changes. The flushing may be light pink to a deep red and occurs in the face and in the nipple-line. It may be triggered by stress, alcohol, exercise and certain types of foods.

Atypical Carcinoid Syndrome

Atypical Carcinoid Syndrome is rare and is associated with foregut carcinoid tumors. It is characterized by extended episodes of flushing, headache, shortness of breath, and in rare cases, lacrimation (tears) ⁴. The flushing can be deep purple and last for hours. It may be followed by increased blood flood to the limbs (arms and legs) and to the trunk (chest, stomach and back). This flush is not brought on by food ⁴.

Carcinoid Crisis

Individuals with Carcinoid Syndrome can also experience Carcinoid Crisis which can occur spontaneously or be stress induced. A Carcinoid Crisis can be a life-threatening event that requires careful monitoring. Symptoms of a Carcinoid Crisis may include severe hypotension or hypertension, irregular and/or rapid heartbeat, wheezing, prolonged flushing, severe dyspnea (shortness of breath), and peripheral cyanosis (lack of oxygenated blood).

Obstructive Symptoms

Midgut and Hindgut

Individuals with midgut and (in rare cases) hindgut carcinoids may experience symptoms such as abdominal pain, nausea, and vomiting, even though diagnostic scanning shows nothing. Many individuals diagnosed with liver metastases have reported having undiagnosed abdominal pain for several years prior to their diagnosis of carcinoid.

Foregut

Individuals with bronchial (lung) carcinoids most commonly present with obstructive symptoms. These symptoms may include chronic lung infection such as bronchitis and pneumonia, breathing difficulties, chest pain, and chronic cough. Less commonly, symptoms may include weakness, nausea, sweating, and Cushing’s Syndrome ⁵.

Carcinoid Heart Disease

Carcinoid tumors can secrete a variety of hormones and vasoactive substances such as serotonin. When these substances are released from liver metastases, the right side of the heart is exposed to them. As a result, patients may experience Carcinoid Heart Disease characterized by plaque lesions in the right side of the heart.

Carcinoid Heart Disease can cause right-sided heart failure. Carcinoid Heart Disease is most common on the right side of the heart but can also occur on the left side. While serotonin production is related to development of Carcinoid Heart Disease, there is evidence of increased cardiac lesions during somatostatin analog therapy ⁶. All carcinoid cancer patients should be familiar with Carcinoid Heart Disease and discuss appropriate monitoring with their physician.

Cushing’s Syndrome

Bronchial (lung) carcinoid tumors can also secrete the adrenocorticotropic hormone (ACTH) which may cause Cushing’s Syndrome. Cushing’s Syndrome is characterized by excessive upper body weight gain, skin disorders (bruising and poor healing), baldness, and psychological disorders such as depression and anxiety.

Zollinger-Ellison Syndrome

Gastrinomas hypersecrete (over produce) gastrin causing Zollinger-Ellison Syndrome. Symptoms of Zollinger-Ellison Syndrome include diarrhea and peptic-ulcers. Patients with Zollinger-Ellison Syndrome may also develop gastric carcinoid as a result of prolonged gastrin hypersecretion.

Carcinoid tumor diagnosis

Carcinoid tumors, like many neuroendocrine tumors, can be very difficult to diagnose. It is common for individuals with carcinoid cancer to remain asymptomatic until the tumors have metastasized or grow large enough to affect normal bodily functions. After an individual develops symptoms, diagnosis can be problematic since the symptoms of carcinoid cancer can mimic other diseases.

If your physician suspects you have a carcinoid tumor, there are specific biochemical tests which measure tumor markers and imaging tests that can help confirm a diagnosis and potentially determine the tumor type, location, load and prognosis. A tissue biopsy of a suspected tumor is, in most cases, the only definitive test.

If you have already been diagnosed with carcinoid cancer, biochemical and imaging tests are very important tools for disease staging and clinical management.

The usual basic tests will be done, including those to look at the blood and other blood components. Other general tests will determine the function of the liver and kidney.

Most of carcinoid tumors are found when tests or procedures are done for other reasons, such as during abdominal surgery.

If a physical exam is done, the health care provider may find signs of:

• Heart valve problems, such as murmur
• Niacin-deficiency disease (pellagra)

Tests that may be done include:

• 5-hydroxyindoleacetic acid (5-HIAA) levels in urine. 5-HIAA is a metabolite (a product from the breakdown) of serotonin. Serotonin is one of the most commonly secreted hormones by carcinoid tumors of the midgut and sometimes those of the foregut.
• Blood tests (including serotonin and chromogranin blood test). Chromogranin A (CgA) is a secretory protein that is common to most neuroendocrine tumor cells, including carcinoid, and is a general tumor marker for neuroendocrine tumors. Since it is secreted into the blood stream it can be measured by a simple blood test. Blood plasma levels of Chromogranin A have been shown to relate to prognosis ⁷. In patients treated with somatostatin analogs Chromogranin A should be used with caution as somatostatin analogs can affect CgA levels ⁸. It has been recommended that CgA readings be taken at consistent time periods from somatostatin analog treatment ⁹. 
  
• CT and MRI scan of the chest or abdomen
• Echocardiogram
• Octreotide radiolabeled scan. Octreotide is a synthetic (man-made), radio-labeled analogue of the naturally occurring hormone somatostatin. Over 90% of all carcinoid tumor cells have receptors for somatostatin. Octreotide, like somatostatin, is able to bind to two of the five receptors (receptors two and five) on carcinoid tumor.
• Endoscopy is a medical procedure that uses an endoscope to view the lining of multiple organs and tracts of the body. An endoscope is a flexible or rigid tube that has imaging capabilities and can enable small surgical procedures. Endoscopy can be used to visualize carcinoid tumors in the lungs and gastrointestinal tract (stomach, small and large intestine and rectum).

Carcinoid tumors and carcinoid syndrome treatment

Surgery to remove the carcinoid tumor is usually the first treatment. It can permanently cure the condition if the tumor is completely removed. If the tumor is caught early, it may be possible to completely remove it and cure the cancer altogether. Otherwise, surgeons will remove as much of the tumor as possible (debulking).

If the tumor has spread to the liver, treatment involves transplantation of liver.

When the entire tumor cannot be removed, removing large portions of the tumor (“debulking”) can help relieve the symptoms.

Octreotide (Sandostatin) or lanreotide (Somatuline) injections are given to people with advanced carcinoid tumors that cannot be removed with surgery.

People with carcinoid syndrome should avoid alcohol, large meals, and foods high in tyramine (aged cheeses, avocado, many processed foods), because they may trigger symptoms.

Some common medicines, like selective serotonin reuptake inhibitors (SSRIs), such as paroxetine (Paxil) and fluoxetine (Prozac), may make symptoms worse by increasing levels of serotonin. However, DO NOT stop taking these medicines unless your provider tells you to do so.

Treatment aims to:

• Locate the tumor;
• Remove the tumor if metastasis (spread to other organs) has not occurred;
• Control carcinoid symptoms if present.

Surgery

• Surgery is the treatment of choice for carcinoid tumors which remain at the site of origin (localized). The extent of the surgical resection depends on the site and size of the tumor;
• Limited role in carcinoid syndrome because almost all have spread to other regions;
• Surgery in carcinoid syndrome has the risk of provoking carcinoid crisis during induction of anesthesia. This can be prevented by giving octreotide before the surgery.

Symptom control

• Avoidance of factors that provoke flushing episodes (e.g. alcohol, physical exertion);
• For mild diarrhea, codeine phosphate can be used;
• In patients with severe symptoms of the carcinoid syndrome, octreotide (a drug resembling the hormone somatostatin) is likely to be effective. The drug is usually well tolerated, with some side effects (e.g. nausea, bloating, loose stools) which often subside. Some patients may develop gallstones;
• Patients with diarrhea who cannot tolerate octreotide can be treated with another drug called cyproheptadine.
• Biological therapy. An injectable medication called interferon alfa, which stimulates the body’s immune system to work better, is sometimes used to slow the growth of carcinoid tumors and to relieve symptoms. Interferon alfa can cause significant side effects, including fatigue and flu-like symptoms.

Metastatic disease

• In patients whose disease has spread/metastasized, surgery is most often considered if the liver is involved. Other treatment approaches include radiofrequency ablation and cryoablation;
• Octreotide decreases symptoms of metastatic disease and slows tumor growth;
• Chemotherapy has been used but with only minor efficacy;
• Another treatment modality is embolization of the hepatic artery (blocking the blood vessel supplying the liver to cut off blood supply to the tumor). Stopping blood supply to liver tumors. In a procedure called hepatic artery embolization, a doctor inserts a catheter through a needle near your groin and threads it up to the main artery that carries blood to your liver (hepatic artery).The doctor injects particles designed to clog the hepatic artery, cutting off the blood supply to cancer cells that have spread to the liver. The healthy liver cells survive by relying on blood from other blood vessels.Hepatic artery embolization can be risky and the procedure is typically performed only in specialized medical centers. Discuss the benefits and risks with your doctor.
• Killing cancer cells in the liver with heat or cold. Radiofrequency ablation delivers heat through a needle to the cancer cells in the liver, causing the cells to die. Cryotherapy is similar, but it works by freezing the tumor.Radiofrequency ablation and cryotherapy are generally safe, though there is a small risk of blood loss and infection.

Carcinoid crisis

In the carcinoid crisis, the blood pressure should be supported by blood transfusion and octreotide should be given.

Lifestyle and home remedies

Talk to your doctor about self-care measures that may improve your signs and symptoms. Self-care measures can’t replace treatment, but they may complement it. Ask your doctor if you should:

• Avoid things that cause skin flushing. Certain substances or situations can trigger flushing, such as alcohol or large meals. Some people experience flushing when they’re feeling stressed or upset. Keep track of what causes your flushing, and try to avoid situations that trigger flushing.
• Consider taking a multivitamin. Chronic diarrhea makes it difficult for your body to process the vitamins and nutrients in the food you eat. Ask your doctor whether taking a multivitamin may be a good idea for you.

Coping and support

You may be relieved to finally find an answer to what’s been causing your signs and symptoms, but a diagnosis of a rare disease, such as carcinoid syndrome, can be stressful. As you develop your way of coping with a cancer diagnosis, talk with your health care team about how you feel and consider trying to:

• Find out enough about carcinoid syndrome to make decisions about your care. Ask your doctor questions about your condition. Ask members of your health care team to recommend resources where you can get more information. Knowing about your condition may enable you to better participate in decisions about your care.
• Talk to other people with carcinoid syndrome. Support groups for people with carcinoid syndrome put you in touch with those who have faced the same challenges you are facing. Ask your doctor about groups in your area. Carcinoid syndrome is rare, though, so you may need to connect with people outside your immediate area.
• Take care of yourself. Do what you can to maintain a healthy lifestyle. Eat a diet full of fruits and vegetables. When you feel up to it, work light exercise into your daily routine. Cut extra stress out of your life when possible. Get plenty of sleep so that you feel rested when you wake up. Take care of your body and mind so that you’re better able to stick to your cancer treatment plan.

1. Carcinoid syndrome. https://medlineplus.gov/ency/article/000347.htm[↩]
2. Kulke, M. H. (2007). Clinical Presentation and Management of Carcinoid Tumors. Hematology/Oncology Clinics of North America, 21, 433-455 https://www.ncbi.nlm.nih.gov/pubmed/17548033[↩][↩]
3. Babovic-Vuksanovic, D., Constantinous, C., Rubin, J., Rowland, C., Schiad, D., Karnes, P. (1999) Familial Occurrence of Carcinoid Tumors and Association with Other Malignant Neoplasms. Cancer Epidemiology, Biomarkers, & Prevention, 8, 715-719. http://cebp.aacrjournals.org/content/8/8/715.long[↩]
4. Tomasseti, P., Migliori, M., Lalli, S., Campana, D., Tomassetti, V., Corinaldesi, R. (2001). Epidemiology, clinical features and diagnosis of gastroenteropancreatic endocrine tumours. Annals of Oncology, 12(2), S95-S99. https://www.ncbi.nlm.nih.gov/pubmed/11762360[↩][↩]
5. Fink, G., Krelbaum, T., Yellin, A., Bendayan, D., Saute, M., Glazer, M., and Kramer, M. R. (2001). Pulmonary Carcinoid: Presentation, Diagnosis and Outcome in 142 Cases in Israel and Review of 640 Cases From the Literature. American College of Chest Physicians, 119(6), 1647-1651. http://journal.chestnet.org/article/S0012-3692(15)52308-8/fulltext[↩]
6. Moller, J., Connolly, H., Rubin, J., Seward, J., Modesto, K., and Pellikka, P. (2003). Factors associated with progression of carcinoid heart disease. New England Journal of Medicine, 348(11), 1005-1015. http://www.nejm.org/doi/full/10.1056/NEJMoa021451[↩]
7. Janson E., Holmberg, L., Stridsberg, M., Eriksson, B., Theodorsson, E., Wilander, E. and Oberg, K. (1997). Carcinoid tumors: analysis of prognostic factors and survival in 301 patients from a referral center. Annals of Oncology, 8(7), 685-690. https://www.ncbi.nlm.nih.gov/pubmed/9296223[↩]
8. Oberg, K., Kvols, L., Caplin, M., Delle Fave, G., de Herder, W., Rindi, G., Rusniewski, P., Woltering, E., Wiedenmann, B. (2004). Consensus report on the use of somatostatin analogs for the management of neuroendocrine tumors of the gastroenteropancreatic system. Annals of Oncology, 15(6), 966-973. https://www.ncbi.nlm.nih.gov/pubmed/15151956[↩]
9. Vinik, A. I., Woltering E. A., Warner, R. P., Caplin, M., O’Dorisio, T. M., Wiseman, G. A., Coppola, D., Go, V. L. W. (2010). NANETS Consensus Guidelines for the Diagnosis of Neuroendocrine Tumor. Pancreas 39(6), 713-734.[↩]