Small cell lung cancer is fast-growing lung cancer that develops in the tissues of the lungs. By the time a person gets a diagnosis, small cell lung cancer has typically spread (metastasized) outside of the lungs. This cancer is also more likely than other types of lung cancer to come back after treatment. Small cell lung cancer is sometimes, but not often, called oat cell cancer because the small, oval-shaped cells look like oat grains under a microscope.
What are the types of small cell lung cancer?
There are two types of small cell lung cancer. Cancer cells grow and spread differently depending on the type. Doctors named the types for the kinds of cells in the cancer and how they look under a microscope:
- Small cell carcinoma.
- Combined small cell carcinoma.
How common is small cell lung cancer?
An estimated 15% of people diagnosed with lung cancer have small cell lung cancer.
Who might have small cell lung cancer?
Smokers, people with a history of smoking and nonsmokers are all at risk for lung cancer. However, small cell lung cancer almost always develops in people who have a long history of tobacco use.
SYMPTOMS AND CAUSES
What causes small cell lung cancer?
While anyone can get lung cancer, current and former smokers are most at risk for small cell lung cancer. Other risk factors include:
- Secondhand smoke.
- Radiation exposure via cancer treatments, home radon or diagnostic imaging scans.
- Family history of lung cancer.
- Human immunodeficiency virus (HIV).
- Workplace exposure to asbestos, arsenic, nickel, tar or other chemicals.
- Air pollution.
- Advanced age.
What are the symptoms of small cell lung cancer?
Early-stage small cell lung cancer that hasn’t spread rarely causes symptoms. As the disease progresses, you may experience:
- Chest pain or discomfort.
- Chronic cough that doesn’t go away or worsens.
- Coughing up blood (hemoptysis).
- Difficulty breathing.
- Facial swelling.
- Fatigue.
- Hoarseness.
- Loss of appetite.
- Swollen neck veins.
- Unexplained weight loss.
- Wheezing.
DIAGNOSIS AND TESTS
How is small cell lung cancer diagnosed?
Chest X-rays are typically the first step to screen for any type of lung cancer. If images show suspicious spots on a lung, your healthcare provider may order one or more of these diagnostic tests:
- Imaging scans: Computed tomography (CT) and positron emission tomography (PET) scans detect lung tumors. These tests also can help gauge cancer spread. CT scans are the primary way to diagnose lung cancer.
- Sputum cytology: This test checks for cancer cells in sputum, mucus coughed up from the lungs.
- Biopsy: A needle biopsy removes tissue samples from the lungs. Lab pathologists check the biopsy for cancer cells.
- Bronchoscopy: Using a bronchoscope, your provider looks inside the lung’s airways for tumors. At the same time, providers can remove tissue samples to biopsy.
What are the stages of small cell lung cancer?
Healthcare providers use a two-stage system to diagnose the spread of small cell lung cancer. This information also helps guide treatment. The two stages of small cell lung cancer are:
- Limited: Cancer is confined to one lung and nearby lymph nodes. (Lymph nodes are part of the lymphatic system that help filter out diseased cells.)
- Extensive: Cancer has spread to the other lung and lymph nodes. It also may have spread to bones, the brain and other organs.
