What is a lung carcinoid tumor?

What is a lung carcinoid tumor?

A lung carcinoid tumor is a type of cancerous tumor made up of neuroendocrine cells. These cells are found throughout the body, including the lungs. They are similar to endocrine cells because both produce hormones or hormone-like substances. In other ways, they resemble nerve cells because both can secrete neurotransmitters.

Sometimes neuroendocrine cells grow too quickly and form a small tumor known as a carcinoid tumor. Carcinoid tumors may form in other organs of the body besides the lungs. In fact, only about 2 out of 10 carcinoid tumors are found in the lungs.

There are two types of lung carcinoid tumors: typical and atypical.

• Typical carcinoids account for about 9 out of 10 lung carcinoids. They grow slowly and rarely spread beyond the lungs.
• Atypical carcinoids are much rarer than typical lung carcinoids. They tend to grow faster than typical carcinoids. There’s a greater chance that they will spread (metastasize) beyond the lungs. Another way to classify lung carcinoid tumors is by their location. Central carcinoids are found in the walls of the large airways of the lungs. Peripheral carcinoids form closer to the edges of the lungs in the smaller airways. Both central and peripheral carcinoids usually are typical carcinoids.