Causes

About 15% of all lung cancer cases are SCLC. 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 people 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 where the lung has partially collapsed. Each of these findings could (but does not always) suggest cancer.

SCLC 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 most cases, your health care provider may need to remove a piece of tissue from your lungs or other areas to be examined under a microscope. This is called a biopsy. There are several ways to do a biopsy:

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

Usually if a biopsy shows 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.) 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)

Treatment

Because SCLC spreads quickly throughout the body, treatment must include cancer-killing drugs (chemotherapy) taken by mouth or injected into the body. Usually, the chemotherapy drug etoposide (or sometimes irinotecan) is combined with either cisplatin or carboplatin.

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

Radiation therapy uses powerful x-rays or other forms of radiation to kill cancer cells. Radiation therapy can be used with chemotherapy if surgery is not possible. Radiation may be used to:

• Treat the cancer, along with chemotherapy, if surgery is not possible
• Help relieve symptoms caused by the cancer, such as breathing problems and swelling
• Help relieve cancer pain when the cancer has spread to the bones

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, some patients with smaller cancers, or who had a good response in their first round of chemotherapy may receive radiation therapy to the brain. This method is called prophylactic cranial irradiation (PCI).

Surgery helps very few patients with SCLC because the disease has often spread by the time it is diagnosed. Surgery may be done when there is only one tumor that has not spread. If surgery is done, chemotherapy or radiation therapy will still be needed.

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

Treatment can often prolong life for 6 - 12 months, even when the cancer has spread.

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.

See also: Lung Cancer

Alternative Names

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

References

Ettinger DS. Lung cancer and other pulmonary neoplasms. In: Goldman L, Ausiello D, eds. Cecil Medicine. 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 197.

National Cancer Institute. Small cell lung cancer treatment PDQ. Updated April 13, 2011.

National Comprehensive Cancer Network. Clinical practice guidelines in oncology: Small cell lung cancer. 2011. Version 2.2012.

Updated: 4/24/2012

Reviewed by: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; and Yi-Bin Chen, MD, Leukemia/Bone Marrow Transplant Program, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.