Small-Cell Lung Cancer

Reviewed by Melinda Ratini, DO, MS on March 21, 2020

What Is Small-Cell Lung Cancer?

Small-cell lung cancer (SCLC) is a disease in which cells in your lung begin growing out of control. It starts in nerve cells or cells that make hormones.

About 10% to 15% of lung cancer cases are small-cell. The other kind is called non-small-cell lung cancer. They’re different in several ways, including:

  • Small-cell lung cancer grows faster.
  • Small-cell lung cancer spreads quicker.
  • Small-cell lung cancer responds well to chemotherapy and radiation therapy.
  • Small-cell lung cancer is most often linked to paraneoplastic syndromes, a group of symptoms that happen when the tumor makes hormone-like chemicals.

Types of Small-Cell Lung Cancer

There are two types of SCLC:

  • Small-cell carcinoma (also called oat cell cancer)
  • Combined small-cell carcinoma

They’re named for the kinds of cells found in each cancer and what they look like.

Small-Cell Lung Cancer Causes

Smoking is a cause of most lung cancers. Small-cell lung cancer is diagnosed most often in heavy smokers. 

Small-Cell Lung Cancer Risk Factors

Some other things also can raise your risk of SCLC, including:

  • Contact with radon gas, which can collect in homes and other buildings
  • A family history of lung cancer
  • Contact with asbestos, arsenic, chromium, and nickel

Small-Cell Lung Cancer Symptoms

Early on, you might not notice any symptoms, or if you do, they may be mild.

Signs of a tumor include:

If the cancer spreads to nearby tissues, you might have:

  • A hoarse voice
  • Shortness of breath
  • Trouble swallowing
  • Swelling of your face and hands

Cancer that’s spread farther can have different symptoms, depending on the affected area. These include:

Paraneoplastic syndromes can cause:

  • Fatigue
  • Loss of appetite
  • Weight gain or loss
  • Severe weakness
  • Trouble balancing or walking
  • Changes in your mental state
  • Changes in skin color, skin texture, and facial features

When to call your doctor

Talk to your doctor if you notice:

  • Shortness of breath
  • Coughing up blood
  • Weight loss for no clear reason
  • A change in your voice
  • A new cough 
  • Fatigue that won’t go away
  • Deep aches or pains with no clear cause

Call 911 or go to the emergency room if you have any of these symptoms:

  • Coughing up large amounts of blood
  • Chest pain
  • Sudden or severe shortness of breath
  • Sudden or severe weakness in your arm or leg
  • Sudden vision problems
  • Seizures

Small-Cell Lung Cancer Diagnosis

Doctors use many tests to figure out if you have lung cancer. You may get one or more of these:

  • Chest X-ray. These images show tumors in your lungs.
  • CT scan. Computerized images can show smaller tumors that X-rays won’t find. They can also tell your doctor if the cancer has spread to your lymph nodes.
  • PET scan. This test can show if the cancer has spread to other parts of your body. Doctors often order it along with a CT scan.
  • Sputum cytology. You cough up some phlegm. A specialist looks at it under a microscope to spot cancer cells.
  • Thoracentesis. Your doctor inserts a needle through your chest wall to take fluid that collects around your lungs.
  • Thoracoscopy. Your doctor runs a small camera through a tiny cut to look inside your chest.
  • Mediastinoscopy. Your doctor makes a small cut at the top of your breastbone and puts in a tool called a mediastinoscope. It’s a long, thin, flexible tube with a light and a tiny camera. They use it to look at lymph nodes in your chest. They might also take samples of your tissue or lymph node to check for cancer.
  • Bronchoscopy. Your doctor puts a thin, flexible tube down your throat and into your lungs to look at the area and take samples of fluid or tumors.
  • Needle biopsy. Another way your doctor can take cells from your lung is to insert a needle through your chest wall and into the lung tissue.
  • Light or electron microscopy. A technician can use regular or high-powered microscopes to look for cell changes in a sample of tissue.
  • Immunohistochemistry. This test uses antibodies tagged with an enzyme or dye. They attach to markers called antigens in a sample of lung tissue to make them show up under a microscope.

Questions for your doctor

  • What treatment do you think is best for me?
  • What is the goal of this treatment? Could it cure my cancer?
  • Is there anything I can do to help treatment work better?
  • What side effects can I expect? How can I manage them?
  • Are there any clinical trials that might be right for me?
  • How will I know if treatment is helping?
  • Should I see a specialist?
  • What if I don’t want treatment?

Small-Cell Lung Cancer Stages

If you have cancer, the test results will tell your doctor whether it has spread and how far. This process is called staging. It helps them plan your treatment.

Small-cell lung cancer is divided into two stages:

  • Limited. The tumor is in only one side of your chest, the tissues between your lungs, and nearby lymph nodes.
  • Extensive. Cancer has spread to other parts of your body.

Small-Cell Lung Cancer Treatment

Your treatment plan will depend on several things, including how far your cancer has spread, your overall health, and what you prefer.

Your doctor will recommend one or more of these treatments:

  • Chemotherapy. You get drugs through an IV or by mouth to kill cancer cells. Chemo is usually the main treatment for SCLC.
  • Radiation therapy. High-energy X-rays kill cancer cells. It’s often used with chemo.
  • Immunotherapy. Also called biologic therapy, these drugs boost your immune system to help it fight cancer.
  • Surgery. This is an option in rare cases in which cancer is limited to a small area.

Small-Cell Lung Cancer Prognosis

You’ll see your doctor for tests every few months in the first year after your diagnosis. After that, you might visit less often.

The success of your treatment depends on how far it’s spread by the time you’re diagnosed. It’s harder to cure extensive SCLC.

Overall, about 6% of people who have small-cell lung cancer live at least 5 years after diagnosis. This number, called the 5-year survival rate, is 31% if the cancer is only one tumor in a lung, 8% to 19% if it has spread to nearby tissues, and 2% if it has spread farther.

Even if your doctor can’t cure your SCLC, treatments might make you feel better and improve your quality of life.

A cancer diagnosis can be stressful. Support groups can help. You’ll meet with people who have the same feelings and who are going through the same things you are. Ask your doctor about groups near you.

Reach out to friends and family for physical and emotional support. Don’t be afraid to ask for help when you need it.

WebMD Medical Reference



American Cancer Society: “If You Have Small Cell Lung Cancer.”, American Society of Clinical Oncology: “Lung Cancer - Small Cell: Introduction.”

National Organization for Rare Disorders: “Small Cell Lung Cancer.”

National Cancer Institute: “Small Cell Lung Cancer Treatment (PDQ) -- Patient Version.”

Mayo Clinic: “Lung cancer.”

UpToDate: “Patient education: Small cell lung cancer treatment (Beyond the Basics).”

American College of Chest Physicians.

University of Pittsburgh Medical Center.

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