What is Carcinoid Syndrome?
Carcinoid syndrome is a collection of symptoms that arise from certain rare tumors. Typically, these tumors are located in the gastrointestinal tract or in the bronchial tubes in the lungs. The main characteristic of these tumors is that they secrete abnormal levels of hormones or active substances causing a cascade of symptoms. In order for carcinoid syndrome to be present, there must be abnormally high levels of these substances circulating within the body.
Serotonin, one of the hormones primarily responsible for carcinoid syndrome, is normally secreted in the gut to regulate the function of the gastrointestinal system. Carcinoid tumors present in the gastrointestinal tract are highly likely to produce serotonin often leading to abdominal symptoms. Another active substances secreted by carcinoid tumors contributing to carcinoid syndrome include histamine and bradykinin. These powerful vasodilators cause blood vessels to expand thereby leading to circulatory problems.
Depending on the location of the tumors, their stage of growth and the amount and type of substances they secrete, symptoms may or may not be present. It is estimated that in 1 out of 10 people diagnosed with carcinoid tumors will develop carcinoid syndrome.
Carcinoid Syndrome symptoms
Typical symptoms seen in carcinoid syndrome include:
• Diarrhea
• Abdominal cramping
• Facial and chest flushing
• Wheezing
• Heart valve problems
Less frequent carcinoid syndrome symptoms may include:
• Wheezing
• Arthritis
• Swelling of the legs or arms
• Prolonged red spots on the body caused by frequent flushing
• Prolonged cyanotic blue spots on the body caused by lack of oxygen after extended periods of flushing
• Nutritional deficiencies of niacin leading to rashes
Diagnosis of carcinoid syndrome
The collection of symptoms that fall under the umbrella of carcinoid syndrome may be misdiagnosed, as symptoms are considered non-specific. Carcinoid tumors are often found during other examinations including colonoscopies or exploratory surgery. Some physicians may even diagnose carcinoid syndrome based on the severity of symptoms then subsequently perform diagnostic workups to locate the carcinoid tumors.
Examinations and procedures individuals may undergo to investigate carcinoid tumors or carcinoid syndrome include:
• Blood and urine tests
• Barium swallow to visualize the small intestines
• CT and MRI scans
• Nuclear medicine scans
• Exploratory surgery including tissue biopsy
Once a tumor has been located, physicians will then determine if the cancer is a primary or a secondary tumor that has metastasized from another cancer. Information gathered from diagnostics and along with symptoms can then lead to a diagnosis of carcinoid syndrome.
Carcinoid Syndrome-Treatment
Depending on individual circumstances, the grade and classification of tumor, and the severity of carcinoid syndrome symptoms, treatment can range from conservative to aggressive. Often, treatment is complex and combines several modalities. Most often these include surgery, chemotherapy and radiation therapy. For those whose tumors are optimal for surgical treatment, the tumor may be removed completely or partially resected. This depends on the location of the tumor, organs affected, comorbidities and overall prognosis.
There are a number of highly toxic chemotherapy drugs that may also be used to treat carcinoid tumors and subsequent carcinoid syndrome, however chemotherapy often has severe and numerous side affects. Radiotherapy is externally applied to target the tumor responsible for causing symptoms of carcinoid syndrome and is generally used to shrink the tumor for symptom management or to be used with other modalities including those mentioned previously.
Other treatments considered for those suffering from carcinoid syndrome is based on symptom management. Instead of curative attempts, the goal is to provide relief from symptoms thereby improving quality of life. Several promising medications include octreotide and interferon, intravenous and injectable medications used to control diarrheal and flushing symptoms. Suffers of carcinoid syndrome may find that the side effects of these medications negate the symptoms they would otherwise suffer from and are also less toxic than chemotherapy. In addition to these medications, others used for symptom management include bronchodilators to help improve breathing, and diuretics to reduce the amount of circulating volume in the body thereby easing strain on the heart and lungs. In extreme cases where carcinoid syndrome affects heart values, surgical replacement of the affected valves may also be considered.
Prevention
While it is difficult to prevent carcinoid syndrome, it is important to be aware of potential triggers that may exacerbate symptoms. Certain foods including those containing high levels of amine, such as caffeinated products, wine, chocolate, and some cheeses can set off the cascade of symptoms. Some individuals find spicy food, processed foods, those high in fat, alcohol and some fruit may also trigger symptoms. In addition to trigger foods, life events including high levels of stress, surgical procedures such as those requiring anesthesia may also contribute to what is considered a carcinoid crisis. This is a sudden onset of acute and severe carcinoid syndrome symptoms which requires immediate medical attention due to their life-threatening potential.
Living with carcinoid syndrome is life altering and complex. While it may not be preventable, it is important to seek support and work with your team of care providers ensuring that your quality of life is at the forefront of treatment.
