Lung cancer - small cell
There are two types of SCLC:
- Small cell carcinoma (oat cell cancer)
- Combined small cell carcinoma
Most SCLCs are of the oat cell type.
Cancer - lung - small cell; Small cell lung cancer; SCLC
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 very 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 of SCLC include:
Other symptoms that may occur with this disease, especially in the late stages, include:
Exams and Tests
The doctor will perform a physical exam and ask about your medical history. You will be asked whether you smoke, and if so, how much and for how long.
When listening to your chest with a stethoscope, the doctor may hear fluid around the lungs or areas where the lung has partially collapsed. Each of these findings may 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
- Positron emission tomography (PET) scan
- Sputum test (cytology to look for cancer cells)
- Thoracentesis (removal of fluid from the chest cavity around the lungs)
In most cases, a piece of tissue is removed 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
Because SCLC spreads quickly throughout the body, treatment must always include cancer-killing drugs (chemotherapy), which are usually given through a vein (by IV).
Treatment with chemotherapy and radiation may be done for people with SCLC that has spread throughout the body (most cases). In this case, the treatment only helps relieve symptoms and prolongs life, but does not cure the disease.
Radiation therapy can be used with chemotherapy if surgery is not possible. Radiation therapy uses powerful x-rays or other forms of radiation to kill cancer cells.
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. This can occur even when there are no symptoms or other signs of cancer in the brain. As a result, some people with smaller cancers, or who had a good response in their first round of chemotherapy may receive radiation therapy to the brain. This therapy is done to prevent spread of the cancer to the brain.
Surgery helps very few people 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 is still needed.
You can ease the stress of illness by joining a cancer support group. Sharing with others who have common experiences and problems can help you not feel alone.
How well you do depends on how much the lung cancer has spread. SCLC is very deadly. Not many people with this type of cancer are still alive 5 years after diagnosis.
Treatment can often prolong life for 6 to 12 months, even when the cancer has spread.
In rare cases, if SCLC is diagnosed early, treatment may result in a long-term cure.
When to Contact a Medical Professional
Call your health care provider if you have symptoms of lung cancer, particularly if you smoke.
If you smoke, now is the time to quit. If you are having trouble quitting, talk with your provider. There are many methods to help you quit, from support groups to prescription medicines. Also try to avoid secondhand smoke.
If you smoke or used to smoke, talk with your provider about getting screened for lung cancer. To get screened, you need to have a CT scan of the chest.
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National Cancer Institute. PDQ Small cell lung cancer treatment. Bethesda, MD. www.cancer.gov. Date last modified January 23, 2015. http://www.cancer.gov/cancertopics/pdq/treatment/small-cell-lung/healthprofessional. Accessed October 7, 2015.
National Comprehensive Cancer Network. NCCN Clinical Practice Guidelines in Oncology: Small cell lung cancer. Version 1.2016. http://www.nccn.org/professionals/physician_gls/pdf/sclc.pdf. Accessed October 7, 2015.
Silvestri GA, Pastis NJ, Tanner NT, Jett JR. Clinical aspects of lung cancer. In: Broaddus VC, Mason RJ, Ernst JD, et al, eds. Murray and Nadel's Textbook of Respiratory Medicine. 6th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 53.
Reviewed By: Yi-Bin Chen, MD, Leukemia/Bone Marrow Transplant Program, Massachusetts General Hospital, Boston, MA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.