A slow-growing cancerous tumor that can grow in several places throughout the body.
A carcinoid tumor often begins in the stomach, appendix, small intestine, colon, rectum, or lungs.
Symptoms often don't appear until late in the disease and are vague. Examples include diarrhea and skin flushing.
Treatment includes surgery and medications, such as drugs that block cancer cells from secreting hormones or boost the immune system.