Small cell lung cancer (SCLC) is a fast-growing type of lung cancer. It spreads much more quickly than non-small cell lung cancer.

There are three different types of small cell lung cancer:

• Small cell carcinoma (oat cell cancer)
• Mixed small cell/large cell carcinoma
• Combined small cell carcinoma

Most small cell lung cancers are the oat cell type.

Causes

About 15% of all lung cancer cases are small cell lung cancer. Small cell lung cancer is slightly more common in men than women.

Almost all cases of SCLC are due to cigarette smoking. SCLC is rare in those who have never smoked.

SCLC is the most aggressive form of lung cancer. It usually starts in the breathing tubes (bronchi) in the center of the chest. Although the cancer cells are small, they grow very quickly and create large tumors. These tumors often spread rapidly (metastasize) to other parts of the body, including the brain, liver, and bone.

Symptoms

• Bloody sputum (phlegm)
• Chest pain
• Cough
• Loss of appetite
• Shortness of breath
• Weight loss
• Wheezing

Other symptoms that may occur with this disease:

• Facial swelling
• Fever
• Hoarseness or changing voice
• Swallowing difficulty
• Weakness

Exams and Tests

Your health care provider will perform a physical exam and ask questions about your medical history. You will be asked whether you smoke, and if so, how much and for how long you have smoked.

When listening to your chest with a stethoscope, your health care provider can sometimes hear fluid around the lungs or areas of partial lung collapse. Each of these findings could (but does not always) suggest cancer.

Small cell lung cancer has usually spread to other parts of your body by the time it is diagnosed.

Tests that may be performed include:

• Bone scan
• Chest x-ray
• Complete blood count (CBC)
• CT scan
• Liver function tests
• MRI
• Positron emission tomography (PET) scan
• Sputum test (cytology, looking for cancer cells)
• Thoracentesis (removal of fluid from the chest cavity around the lungs)

In some cases, your health care provider may need to remove a piece of tissue from your lungs for examination under a microscope. This is called a biopsy. There are several ways to do this:

• Bronchoscopy combined with biopsy
• CT scan-directed needle biopsy
• Endoscopic esophageal ultrasound (EUS) with biopsy
• Mediastinoscopy with biopsy
• Open lung biopsy
• Pleural biopsy

Usually, if a biopsy reveals cancer, more imaging tests are done to find out the stage of the cancer. (Stage means how big the tumor is and how far it has spread.) However, the traditional staging system, which uses numbers to tell how advanced the cancer is, is usually not used for patients with SCLC. Instead, SCLC is classified as either:

• Limited (cancer is only in the chest and can be treated with radiation therapy)
• Extensive (cancer has spread outside the chest)

The majority of cases are extensive.

Treatment

Because SCLC spreads quickly throughout the body, treatment must include cancer-killing drugs (chemotherapy) taken by mouth or injected into the body.

• Chemotherapy may be combined with radiation therapy of the lungs in people who have limited disease.
• The most commonly used drugs in the U.S. are etoposide with either cisplatin or carboplatin.

Because the disease has usually spread by the time it is diagnosed, very few patients with SCLC are helped by having surgery. Surgery is only considered when there is only one tumor that has not spread. Chemotherapy or radiation will be needed after surgery.

Combination chemotherapy and radiation treatment is given to people with extensive SCLC. However, the treatment only helps relieve symptoms. It does not cure the disease.

Often, SCLC may have already spread to the brain, even when there are no symptoms or other signs of cancer in the brain. As a result, radiation therapy to the brain may be given to some patients with smaller cancers, or to those who had a good response in the first round of chemotherapy. This method is called prophylactic cranial irradiation (PCI).

Support Groups

For additional information and resources, see cancer support group.

Outlook (Prognosis)

How well you do depends on how much the lung cancer has spread.

Without treatment, the average survival is 2 -4 months. Treatment can often prolong life to 6 - 12 months in patients with extensive disease. About 10% of patients with limited spread will show no evidence of cancer at 2 years.

This type of cancer is very deadly. Only about 6% of people with this type of cancer are still alive 5 years after diagnosis.

Possible Complications

• Cancer spreads to other parts of the body
• Side effects of surgery, chemotherapy, or radiation therapy

When to Contact a Medical Professional

Call your health care provider if you have symptoms of lung cancer (particularly if you smoke).

Prevention

If you smoke, stop smoking. It's never too late to quit. In addition, you should try to avoid secondhand smoke.

Routine screening for lung cancer is not recommended. Many studies have been done to look at this idea, but physicians have concluded that, at this time, screening would not help improve a person's chance for a cure.

Alternative Names

Cancer - lung - small cell; Small cell lung cancer; SCLC