Carcinoid tumors are a type of slow-growing cancer that usually develops in the gastrointestinal tract, particularly in the small intestine, but can also occur in other areas like the lungs. These tumors arise from neuroendocrine cells, which are responsible for producing hormones. While they often grow unnoticed, they can sometimes release hormones into the bloodstream, leading to various symptoms. Symptoms of carcinoid tumors can include flushing of the skin, diarrhea, and abdominal pain. Diagnosis typically involves imaging tests and blood tests to check hormone levels. Treatment options may include surgery, medication, and sometimes radiation therapy, depending on the tumor's location and stage.