Lung cancer is a malignant tumor of the lungs. There are many types of lung cancer, but most can be categorized into two basic types, "small cell" and "non-small cell." Small cell lung cancer is generally faster growing than non-small cell, but more likely to respond to chemotherapy.

There are several different subtypes of non-small cell lung cancer -- adenocarcioma, squamous cell carcinoma, and large cell carcinoma. However, the outlook is similar for these subtypes and they are treated the same.

Non-small cell cancer is divided into four stages, I-IV.

Lung cancer is one of the most common cancers in the world and is the leading cause of cancer death in men and women in the United States. Over 150,000 people die in the U.S. every year from lung cancer.

Most lung cancers are caused by cigarette smoking. The more cigarettes you smoke per day and the earlier you started smoking, the greater the risk of lung cancer.

Second-hand smoke has also been shown to increase risk. Government surveys show that as many as 3,000 people each year develop lung cancer from second-hand smoke. High levels of pollution, radiation, and asbestos exposure may also increase risk.

Lung cancer begins in cells that line the airways and usually invades adjacent tissues or other organs before symptoms are noticed.

• Cough
• Bloody sputum
• Shortness of breath
• Wheeze
• Chest pain
• Loss of appetite
• Weight loss

Additional symptoms that may be associated with this disease:

• Weakness
• Swallowing difficulty
• Nail abnormalities
• Joint pain
• Hoarseness or changing voice
• Facial swelling
• Facial paralysis
• Eyelid drooping
• Bone pain or tenderness

When listening to the chest with a stethoscope, the doctor can sometimes detect fluid that has collected around the lungs from a cancer.

Tests that may be performed include:

• Chest X-ray
• CAT scan of the chest
• Positron Emission Tomography (PET) scan
• Bronchoscopy with washings and biopsy for cytology
• Pleural biopsy
• CAT scan directed needle biopsy
• Mediastinoscopy with biopsy
• Open lung biopsy

This disease may also alter the results of the following tests:

• PTH
• Serum sodium
• CEA

The treatment depends upon the stage of the cancer. Most patients with stage I and II non-small cell tumors, and some patients with stage III tumors, can undergo surgery with the goal of being cured. Stage IV means the cancer has spread to other sites in the body (most often bone, brain, or liver) and is, in most cases, not curable.

• Surgery to cut out the tumor is usually done when the cancer has not spread beyond the lung and selected lymph nodes (stage I, II and selected cases of stage III).
• Some patients will undergo chemotherapy or a combination of chemotherapy and radiation therapy prior to surgery. Recent data suggests that this approach might be the best treatment for some patients.
• Some patients may be helped by chemotherapy after surgery for non-small cell lung cancer. Data presented in 2003 showed increased survival for patients who received this type of therapy, which may now be indicated in certain circumstances.
• The combination of chemotherapy and radiation therapy is often used for cancer confined to the lung and lymph nodes that cannot be removed by surgery (stage III).
• Chemotherapy alone is often used when the cancer has spread (stage IV). Chemotherapy has been shown to prolong the life and improve the quality of life in some stage IV patients.

For additional information and resources, see cancer support group.

For non-small cell cancer, cure rates are related to the stage of disease and whether surgery is feasible.

• Stage I and II cancer can be cured with surgery, sometimes in more than 50% of cases.
• Stage III tumors are cureable in some circumstances, but cure rates are much lower.
• Patients with stage IV disease are almost never cured, and the goals of therapy are to extend their life and improve the quality of life.

• Spread of disease beyond the lung
• Side effects of surgery, chemotherapy, or radiation therapy

If you smoke, stop smoking. Try to avoid second-hand smoke.

There is no conclusive evidence that screening for lung cancer with chest X-rays or CAT scans is beneficial for patients at high risk of developing non-small cell lung cancer. However, some recent studies have suggested that specialized CT scans called "spiral CAT scans" may help improve cure rates by detecting lung cancer at an earlier stage. This is still under investigation, and such screening is not considered the standard of care.