^{Immunology and Oncology}

An endocrine tumour is a growth that affects the parts of the body that secrete hormones. Because an endocrine tumour arises from cells that produce hormones, the tumour itself can produce hormones. These hormones are produced in excessive amounts by endocrine tumours and then released into the blood. The excessive amounts of hormones in the blood produce marked abnormal effects on the body. A neuroendocrine tumour begins in the area showing a combination of hormone-producing endocrine cells and nerve cells. Neuroendocrine cells are found throughout the body in organs such as the lungs and gastrointestinal tract, including the stomach and intestines. Neuroendocrine cells perform specific functions, such as regulating air and blood flow through the lungs and controlling how quickly food moves through the gastrointestinal tract. They are other types of tumours in endocrine and neuroendocrine tumours