When carcinoid tumors produce excessive amounts of hormones that circulate throughout the body, a condition called carcinoid syndrome can occur. This syndrome, which develops in approximately 10 percent of patients, is more common in carcinoids of the midgut, the foregut, and in those that have metastasized (especially to the liver). Symptoms of carcinoid syndrome depend on which hormones are produced by the tumor.
During the course of the disease, approximately 70 percent of carcinoid syndrome patients experience a sudden red rash that usually develops on the face and neck and is accompanied by feelings of warmth and itching (called flushing). Episodes of flushing may be spontaneous or may be triggered by stress, alcohol, exercise, or consumption of certain foods, such as cheese.
Other symptoms of carcinoid syndrome include the following:
- Abdominal pain
- Bluish tint to the skin (cyanosis)
- Enlargement of peripheral body parts including face, head, hands, and feet (acromegaly)
- Erectile dysfunction (impotence, ED)
- Heart damage (e.g., endocardial fibrosis)
- Malnutrition (caused by malabsorption of foods)
- Reduced sex drive (libido)
- Skin lesions