Carcinoid syndrome occurs when a carcinoid tumor secretes chemicals, such as serotonin, histamine, substance P, and kallikrein, into the bloodstream. Carcinoid tumors occur most commonly in the gastrointestinal tract including the stomach, small intestine, appendix, colon, and rectum, or in the lungs. The syndrome typically occurs in patients who have advanced carcinoid tumors. It is unclear what causes carcinoid tumors to appear.
Treatment for carcinoid syndrome usually involves treating the site of the tumor. Most people who experience carcinoid syndrome have an advanced cancer that has spread to the liver. This syndrome may be difficult to cure because of the advanced state of the carcinoid tumors. Due to this, medications are available to help patients relieve symptoms for comfort.
Signs and symptoms of carcinoid syndrome include:
- Skin flushing
- Facial skin lesions
- Breathing difficulty
- Rapid heartbeat
- Abdominal pain
- Nausea and vomiting
Various complications in patients that may be caused by carcinoid syndrome are carcinoid heart disease, bowel obstruction, and carcinoid crisis. Signs and symptoms of these complications include:
- Carcinoid heart disease: Fatigue and shortness of breath during physical activity
- Bowel obstruction: Severe cramping, abdominal pain, and vomiting
- Carcinoid crisis: Severe episode of flushing, low blood pressure, confusion, and breathing difficulty