Lung cancer arises from the cells of the lung tissue. The two primary forms of the disease, small cell and non-small cell lung cancer, differ in their appearance under the microscope and response to various cancer treatments. Medical professionals refer to the extent and spread of lung cancer according to stages, designated I through IV. Stage IV lung cancer is the most advanced form of the disease.
Significance
The American Cancer Society estimates that more than 222,500 men and women in the United States will be newly diagnosed with lung cancer in 2010. Approximately 157,300 Americans will lose their lives to the disease in the same timeframe. Lung cancer remains the leading cause of cancer deaths in the United States, accounting for 29 percent and 26 percent of all cancer deaths among men and women, respectively.
Diagnosis
The National Cancer Institute explains that stage IV lung cancer involves tumors in both lungs, spread of the cancer to other organs or cancerous fluid around the lungs or heart. At the time of diagnosis, lung cancer patients go through a series of tests to determine the extent of the disease. Common diagnostic tests used to diagnosis of stage IV lung cancer include CT and MRI scans, bone scans and positron emission tomography, or PET, scans. Each of these tests utilizes different technology to detect the presence of lung cancer spread, or metastasis, in other body tissues.
Symptoms
People with stage IV lung cancer commonly manifest both lung-related and metastatic symptoms. Although lung cancer can spread to any body tissue, the most common sites of metastasis include the brain, liver, bones, adrenal glands and kidneys, notes the National Cancer Institute. Lung-related symptoms of stage IV disease commonly include chronic cough, shortness of breath, wheezing and painful breathing. Possible symptoms associated with metastasis include bone pain, abdominal pain, headaches, impaired memory or thought processes, nausea, vomiting, dizziness, weight loss, jaundice and weakness.
Treatment
Treatments for stage IV lung cancer focus on palliative and supportive care. Palliative treatments may slow the rate of cancer growth and spread. Supportive care minimizes or alleviates the symptoms and discomfort of the disease to improve quality of life. Radiation therapy often proves useful in shrinking symptomatic lung, bone or brain tumors, reports the National Cancer Institute. Chemotherapy may extend short-term survival. Laser or freezing therapy and other forms of local tumor control may reduce the size of cancerous masses causing pain or interfering with organ function. Pain and symptom control remain high-priorities in the medical management of stage IV lung cancer.
Prognosis
As of 2010, stage IV lung cancer remains an incurable disease. Although disease prognosis varies from one person to another, medical professionals rely on the experiences of other cancer patients to determine the likely prognosis for a person with a given stage of lung cancer. The American Cancer Society reports that the 5-year survival rate is 1 percent for stage IV non-small cell lung cancer and 2 percent for stage IV small cell lung cancer.
References
- American Cancer Society: Cancer Facts and Figures 2010
- National Cancer Institute: Stages of Non-Small Cell Lung Cancer
- National Cancer Institute: Stages of Small Cell Lung Cancer
- Treatment: Stage IV Non-Small Cell Lung Cancer
- National Cancer Institute: Treatment, Extensive-Stage Small Cell Lung Cancer
