Lung Cancer Basics

Whether you’re a person who has lung cancer, or a caregiver for someone who does, you may find it useful to review some basic facts.

Lung cancer definition and types

In lung cancer, certain cells in the lungs are dividing and growing uncontrollably. A tumor is a group of these uncontrolled cells.

There are two major types of lung cancer: small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC). About 20% of all lung cancers are SCLC; the remaining 80% are NSCLC. Within NSCLC are three cancer subtypes: 1. Adenocarcinoma, which starts near the outer edges of the lungs and is the most common form of NSCLC; 2. Squamous cell carcinoma, which starts in the breathing tubes and grows fairly slowly, and 3. Large cell carcinoma, which starts in the smaller breathing tubes and tends to grow and spread (metastasize) quickly.

Statistics

• Lung cancer (both small cell and non-small cell) is the second most common cancer in both men (after prostate cancer) and women (after breast cancer), accounting for about 15% of all new cancers.
• About 215,000 new cases of lung cancer (both types) were expected in 2008.
• On average, men have a 1 in 13 lifetime chance of developing lung cancer; women have a 1 in 16 chance.

Symptoms

Most lung cancers don’t cause any symptoms until they have spread. The most common symptoms are not necessarily caused by cancer. Still, since early treatment can make a big difference in the outcome of the disease, talk with your doctor if you have any of these symptoms:

• Persistent cough.
• Chest pain made worse by deep breathing or coughing.
• Hoarseness.
• Weight loss; loss of appetite.
• Bloody or rust-colored spit of phlegm.
• Shortness of breath.
• Recurrent infections such as bronchitis and pneumonia.
• Wheezing.

When lung cancer has spread to other organs, it may cause bone pain, weakness of the arms or legs, headache, or yellow coloring of the skin and eyes.

Risk Factors

The risk of getting lung cancer is influenced by several factors. Smoking is the number one cause of lung cancer and is responsible for more than 80% of all lung cancer cases. Some other risk factors include:

• Exposure to secondhand smoke.
• Exposure to radon, asbestos, certain metals such as chromium, some organic chemicals, and radiation.
• Air pollution.
• A history of tuberculosis.
• Genes can also be a factor.

Staging

How far has the cancer spread? This is the question answered by "Staging", a system used to classify the severity of lung cancer. Staging is extremely important because it determines the treatment, and the prospects of recovery.

Stages are identified in groups that start at 0 and go up in Roman numerals, from 0 through IV (0-4) Generally, the lower the number, the less the cancer has spread. This is an overview of stages of lung cancer and what they mean in most cases:

• Stage 0: Only a few layers of cancer cells are detected within one local area.
• Stage I: The tumor in the lung is small and only in the lungs.
• Stage II: The tumor is either more advanced, or has spread to the lymph nodes near the lungs.
• Stage III: The tumor has spread to nearby tissue and/or more distant lymph nodes.
• Stage IV: The tumor has spread to other organs; commonly the brain, bone, adrenal glands, opposite lung, and liver.

If you’re not clear about the stage of your cancer, don’t hesitate to ask your healthcare provider. For additional information on staging, please visit www.cancer.org. You need to understand so that you and your doctor can together select the treatment that’s most appropriate for you.

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