A Guide to Carcinoid Tumors in the Lung

Medically Reviewed By Adithya Cattamanchi, M.D.
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Lung carcinoid tumors are a rare type of tumor that can develop in the bronchi of the lungs. They are slower growing than other types of lung cancers. However, lung carcinoid tumors may become serious and require treatment.  Lung carcinoid tumors are slow growing and make up less than 1% of all lung cancers. Many times, there are no symptoms, and people discover this cancer during testing for other conditions. Treatment typically involves the surgical removal of the tumor. 

This guide explains carcinoid tumors, their different types, and their symptoms. It also discusses what causes them, and the process of diagnosis and treatment. 

What is a lung carcinoid tumor?

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Photography by Lucas Ottone/Stocksy United

A lung carcinoid tumor is a rare type of lung cancer. These tumors are typically slow growing and usually do not spread to other parts of the body. However, they can be difficult to treat because they may be advanced when found. 

Lung carcinoid tumors are typically not fatal. However, they can cause serious health problems if untreated.

Where it occurs in the lung

Lung carcinoid tumors typically grow in the lining of the bronchi. 

The bronchi are airway passages in the lungs. They branch off of the windpipe, or trachea, into the right and left lungs. From there the bronchi continue to branch several more times.

What are the different types of carcinoid tumors in the lung?

There are two types of carcinoid tumor in the lungs: typical carcinoid tumor and atypical carcinoid tumor. 

Typical carcinoid tumors are usually slow growing and less likely to spread to other parts of the body. They make up about 9 out of 10 lung carcinoid tumors.

Atypical carcinoid tumors are more likely to grow quickly and spread to other parts of the body. They are much less common than typical carcinoid tumors. They are more common in people who smoke.

Sometimes health professionals label the tumor by where it grows in the lung, as a central tumor or a peripheral tumor. Central carcinoid tumors grow in the middle of the lung. Peripheral carcinoid tumors grow toward the outer edges of the lung.

What are the symptoms of carcinoid tumors in the lung?

Half of the people with carcinoid tumors in the lungs have no symptoms. Those who do have symptoms may experience signs of airway obstruction, such as:

Sometimes these symptoms lead healthcare professionals to incorrectly diagnose the person with asthma.

Other lung carcinoid tumor symptoms may include:

Learn more about the symptoms of lung cancer.

What causes carcinoid tumors in the lung?

Lung carcinoid tumors occur when neuroendocrine cells grow out of control. Neuroendocrine cells also are found in other areas of the body, such as the digestive and urinary tract. In the lungs, these cells have several functions, including:

  • helping control air and blood flow
  • helping control the growth of other lung cells
  • detecting the levels of oxygen and carbon dioxide in the air you breathe and releasing chemicals to help the lungs adjust to the changes

Cancer occurs when cells start to grow out of balance. This can happen when the cells undergo damage from carcinogens that alter their genetics. 

What are the risk factors for developing carcinoid tumors in the lung?

The actual cause of this cancer is unknown. However, experts agree that there are several risk factors, including:

  • Biological sex: People assigned female at birth are more likely to get carcinoid tumors in the lung than people assigned male at birth.
  • Ethnicity: White people are more common than African American, Asian American, Hispanic, or Latino people to get these tumors.
  • Age: This cancer typically occurs in people 45–55 years old, but it can occur at any age.
  • Family history: Having someone in your family who has this cancer may put you at higher risk.
  • Smoking: Smoking tobacco does not appear to be linked with typical lung carcinoid tumors. However, there may be a link to atypical lung carcinoids.
  • Multiple endocrine neoplasia type 1: People with this inherited gene are at higher risk.

How do doctors diagnose carcinoid tumors of the lung?

Many times, testing for another medical condition reveals these tumors.

If you have symptoms suggestive of a tumor in your lung, your primary healthcare professional will perform a physical exam, review your health history and medications, and order some tests. 


A carcinoid lung tumor typically shows on an X-ray only 40% of the time. Most of the time, a CT scan will reveal it.

A bronchoscopy is the gold standard test for diagnosing carcinoid tumors in the lung. Bronchoscopy involves inserting a small camera through the airway to gather images and a biopsy of the tumor. 

A PET scan may determine where a cancer is and whether it has spread.

What are the different stages of carcinoid tumors of the lung?

After discovery of a lung carcinoid tumor, the next step is to determine if the tumor has spread, or metastasized, and how far.

Health professionals use the TNM system to stage lung carcinoid tumors. This system considers the size of the tumor (T), if it has spread to the lymph nodes (N), and if it has metastasized (M). 

This information helps determine treatment and survival rates

How do doctors treat carcinoid tumors of the lung?

The typical treatment for carcinoid tumors entails surgical removal of the tumor.

This type of tumor does not respond to chemotherapy. However, there may be circumstances in which radiation may be an option.

Learn about lung cancer treatment options by stage.

What is the outlook for carcinoid tumors of the lung?

With prompt treatment, many people with carcinoid tumors go on to live a full life.

The tumor type determines the outlook. The 5-year survival rate for a typical carcinoid is about 90%. However, for atypical tumors, the 5-year survival rate can be about 60%.

A relative survival rate shows how long someone with a specific condition may live after their diagnosis compared with someone without the condition. 

For example, a 5-year relative survival rate of 70% means that 70 out of 100 people diagnosed with a condition are still living at least 5 years from the time of diagnosis.

It is most important to remember that figures are estimates, and everyone is different. Talk with your doctor about your specific condition.

Other frequently asked questions

Here are questions people also ask about carcinoid tumors of the lung.

Are lung carcinoid tumors curable?

With prompt surgical treatment, certain lung carcinoid tumors are removable. These types of tumors do not respond to chemotherapy, and only sometimes to radiation. 

Is a carcinoid tumor considered lung cancer?

Yes, carcinoid lung tumors are considered a type of lung cancer. However, this type of cancer is generally less aggressive and slower growing.

How long can you live with a lung carcinoid tumor?

How long you can live with lung carcinoid tumors depends on the type of tumor you have. Typical tumors have a 5-year survival rate of greater than 90%. Atypical tumors do not have such positive percentages. 

Read more frequently asked questions about lung cancer.


A carcinoid tumor is a rare type of cancer that grows in the airways of the lung. These tumors are slow growing and may not cause any symptoms for many years. When they do cause symptoms, the symptoms tend to be mild at first and get worse over time. 

Treatment options include surgery and sometimes radiation therapy. The outlook depends on the size and location of the tumor, and whether it has spread to other parts of the body. With prompt treatment, many people with carcinoid tumors go on to live a full life.

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Medical Reviewer: Adithya Cattamanchi, M.D.
Last Review Date: 2022 Dec 22
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THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Never ignore professional medical advice in seeking treatment because of something you have read on the site. If you think you may have a medical emergency, immediately call your doctor or dial 911.
  1. Keith, R. L. (2022). Bronchial carcinoid. https://www.merckmanuals.com/professional/pulmonary-disorders/tumors-of-the-lungs/bronchial-carcinoid?query=lung
  2. Limaiem, F., et al. (2022). Lung carcinoid tumors. https://www.ncbi.nlm.nih.gov/books/NBK537080/
  3. Lung carcinoid tumor. (n.d.). https://www.cancer.org/cancer/lung-carcinoid-tumor.html
  4. Noguchi, M., et al. (2020). Pulmonary neuroendocrine cells: Physiology, tissue homeostasis and disease. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7774893/