Signs and Symptoms of Lung Carcinoid Tumors

About 2 of 3 people with carcinoid tumors will have signs or symptoms that will lead to the diagnosis of the disease. But because carcinoids tend to grow slowly, they may not cause symptoms for several years in some people, or they may be found by medical tests done for other reasons.

Central carcinoids

Most carcinoid tumors start in the large bronchial tubes leading into the lung. Symptoms can include:

  • Cough, which can sometimes be bloody
  • Wheezing
  • Shortness of breath
  • Chest pain, especially when taking deep breaths

Large carcinoids can cause partial or complete blockage of an air passage, which can lead to pneumonia (an infection in the lung). Sometimes a doctor may suspect a tumor only after treatment with antibiotics doesn’t cure the pneumonia.

Peripheral carcinoids

Some tumors start in the smaller airways toward the outer edges of the lungs. They rarely cause any symptoms unless there are so many of them that they cause trouble breathing. Usually they are found as a spot on a chest x-ray or CT scan that is done for an unrelated problem.

Symptoms caused by hormones from the tumor

Some carcinoid tumors can make hormone-like substances that are released into the bloodstream. Lung carcinoids do this far less often than gastrointestinal carcinoid tumors.

Carcinoid syndrome: Rarely, lung carcinoid tumors release enough hormone-like substances into the bloodstream to cause symptoms. This results in the carcinoid syndrome. Symptoms can include

  • Facial flushing (redness and warm feeling)
  • Diarrhea
  • Wheezing
  • Fast heartbeat.

Many patients find that stress, heavy exercise, and drinking alcohol can bring on these symptoms or make them worse.

Over a long time, these hormone-like substances can damage heart valves, causing:

  • Shortness of breath
  • Weakness
  • Heart murmur (an abnormal heart sound)

Cushing syndrome: In rare cases, lung carcinoid tumors may make a hormone called ACTH. This causes the adrenal glands to make too much cortisol (a steroid hormone) and other hormones. This can lead to:

  • Weight gain
  • Easy bruising
  • Weakness
  • Drowsiness
  • High blood sugar (or even diabetes)
  • High blood pressure
  • Increased body and facial hair

The symptoms and signs above may be caused by lung carcinoid tumors, but they can also be caused by other conditions. Still, if you have any of these problems, it’s important to see your doctor so the cause can be found and treated, if needed.

The American Cancer Society medical and editorial content team
Our team is made up of doctors and master's-prepared nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.

Last Medical Review: February 5, 2015 Last Revised: February 24, 2016

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