Lung cancer, the growth of malignant cells in the lungs, is the leading cause of death from cancer in the United States for both men and women. Most cases occur between ages 45 and 75, after years of exposure to cigarette smoke or other pollutants.
The types of primary lung cancer (cancer that originates in the lungs) may be grouped into two categories: small-cell carcinoma and non-small-cell carcinoma. Non-small-cell carcinoma comprises several types of lung cancers and is responsible for up to 80 percent of cases. Primary lung cancer can spread to essentially any organ, where it may produce more disabling symptoms.
The outlook is poor for all types of lung cancer unless the cancer is detected very early and can be surgically removed. Small-cell carcinoma is the most difficult to treat as it is often diagnosed after it has spread to many organs. Despite being very responsive to chemotherapy and radiotherapy, individuals with small-cell carcinoma commonly relapse within a year.
In many instances, the disease is preventable: Over 90 percent of cases are caused by smoking. Nonsmokers have only a small risk, and those who quit smoking—even after smoking for years—greatly reduce their risk.
The lungs are also a frequent site of secondary cancer, which has spread from elsewhere in the body. Such tumors are almost always incurable.
Symptoms of Lung Cancer
- Cough, sometimes with bloody sputum.
- Wheezing and shortness of breath.
- Chest pain.
- Pain in the shoulder and arm.
- Fatigue.
- Weight loss.
- Clubbed fingers.
- Hoarseness.
- Swollen neck and face; swallowing difficulty.
- Enlarged lymph nodes in the neck.
What Causes Lung Cancer?
- Cigarette smoking is by far the most common cause of primary lung cancer. Cigar smoking has also been associated with lung cancer.
- Air pollution, including so-called passive or second hand smoke, may contribute to lung cancer.
- Exposure to toxic substances, such as radon and other radioactive gases, asbestos, nickel, ionizing radiation, and arsenic, may cause lung cancer.
- Chronic bronchitis is associated with an increased risk of lung cancer.
Prevention of Lung Cancer
- Abstain from smoking; try to limit your exposure to second-hand smoke and air pollution.
- Homes may be tested for radon using a kit available in most hardware stores.
Diagnosis of Lung Cancer
- Patient history and physical examination.
- Sputum sample.
- Chest x-rays, CT (computed tomography) scans, and MRI (magnetic resonance imaging). PET (positive emission tomography) may be done when considering surgery.
- Bronchoscopy (passage of a thin, hollow, flexible tube into the windpipe to allow the main bronchial passages to be viewed).
- A biopsy of cancerous tissue is essential.
How To Treat Lung Cancer
- Surgical removal is the preferred treatment for localized non-small-cell carcinomas (those that have not yet spread). Part or all of the affected lung may be removed.
- Radiation therapy may be used to treat non-small-cell carcinoma in addition to surgery, or for patients ineligible for surgery.
- For both non-small-cell and small-cell carcinomas, a combination of chemotherapy and radiation or radiation alone may be used to treat localized disease. Chemotherapy is used to treat extensive disease.
When To Call A Doctor
- Call a doctor if you develop symptoms of lung cancer, especially cough, weight loss, or fatigue.
- Get regular lung examinations if you are age 45 or over and smoke heavily.
For more information on lung cancer and other lung diseases, click on this link -- Johns Hopkins Health Alerts: Lung Diseases
