Carcinoid is a type of cancer made up of neuroendocrine cells. Most start in the lungs where they are divided into two groups – typical carcinoid and atypical carcinoid. These tumours can also be found in the colon and pancreas where they are usually given the name well differentiated neuroendocrine tumour.

Is a carcinoid a type of cancer?

All carcinoids can spread to other parts of the body and for this reason, doctors consider them to be a type of slow-growing cancer. Some tumours produce large amounts of chemicals such as serotonin that can lead to symptoms such as sweating, abdominal pain, and diarrhoea. Doctors describe these symptoms as carcinoid syndrome. These symptoms typically only occur if the tumour has spread to the liver.

What does a carcinoid look like under the microscope?

When examined under the microscope, carcinoids are made up of cells that all look very similar. Pathologists often describe the nucleus of the cell as “salt and pepper” because the chromatin or genetic material looks like small dark dots on a white background. Additional tests such as immunohistochemistry may be performed to help make the correct diagnosis.