# What are carcinoid tumors? Canonical page: https://clinicsjo.com/en/faq/what-are-carcinoid-tumors Language: en Category: oncology Publisher: ClinicsJo Published: 2026-09-13T08:09:51.027Z Content updated: 2026-09-13T08:09:51.027Z Translation (ar): https://clinicsjo.com/ar/faq/what-are-carcinoid-tumors Carcinoid tumors, also known as gastrointestinal neuroendocrine tumors, are a rare type of cancer that arises in the lining of the digestive tract [\[1\]](). These tumors are often slow-growing [\[3\]](). Carcinoid tumors consist of a special type of neuroendocrine cell that resembles nerve cells and hormone-producing cells. These cells are distributed throughout the chest and abdomen but are found most commonly in the digestive tract [\[1\]](). Neuroendocrine cells produce hormones that help control digestive juices and the movement of food through the stomach and intestines. Carcinoid tumors may also produce hormones and release them into the body [\[1\]](). ## Common Locations of Carcinoid Tumors Carcinoid tumors most often appear in the lining of the digestive tract, specifically in the small intestine, the appendix, and the rectum [\[1\]](). In some cases, more than one tumor may form [\[1\]](). Although rare, they can also appear in the lungs [\[3\]](). ## Carcinoid Tumors in Children Gastrointestinal carcinoid tumors in children are a rare type of cancer that develops in neuroendocrine cells [\[2\]](). These tumors often form in the appendix, a small sac attached to the beginning of the large intestine [\[2\]](). They are usually discovered incidentally during an appendectomy (surgery to remove the appendix) [\[2\]](). Neuroendocrine tumors of the appendix in children tend to grow slowly and rarely spread to other parts of the body [\[2\]](). In rare cases, neuroendocrine tumors can also form in other parts of the digestive system such as the stomach, intestines, pancreas, or liver [\[2\]](). ## Carcinoid Syndrome In some cases, carcinoid tumors may produce hormones that can cause carcinoid syndrome. This syndrome occurs if the tumor has spread to the liver or other parts of the body, and the liver enzymes cannot destroy the excess hormones produced by the tumor, leading to high levels in the body [\[1\]](). This can also occur if cancer cells enter the bloodstream [\[1\]](). Symptoms of carcinoid syndrome include flushing or a feeling of warmth in the face and neck, abdominal pain, a feeling of bloating, diarrhea, difficulty breathing or wheezing, and a rapid heartbeat [\[1\]](). For more information on the diagnosis and treatment of these tumors, you can visit [Carcinoid Tumors: Diagnosis and Multidisciplinary Treatment (Arabic)](). ## What should you do if you suspect you have carcinoid tumors? Because carcinoid tumors may not cause any symptoms in the early stages [\[1\]](), or their symptoms may mimic other conditions, it is essential to consult a doctor if you notice any of the mentioned symptoms, such as persistent abdominal pain, changes in bowel habits, or unexplained weight loss [\[1\]](). Early diagnosis helps in determining the best treatment options. Do not attempt to diagnose or treat yourself, as it requires specialized medical evaluation to determine the nature of the symptoms and develop an appropriate treatment plan based on your individual condition, the tumor location, and the extent of its spread [\[1\]](). ## Medical references - [Gastrointestinal Neuroendocrine Tumors Treatment (PDQ®)–Patient Version]() - [Carcinoid Tumors]() - [Childhood Gastrointestinal Neuroendocrine Tumors (PDQ®)–Patient Version]() General health education; not a substitute for individualized clinical assessment. Citation URL: https://clinicsjo.com/en/faq/what-are-carcinoid-tumors#answer