The lungs are like two big sponges, soaking up external contaminants. Often, this can lead to lung cancer -- one of the most common forms of malignancy.

Signs And Symptoms

Early detection can have an effect on the cure rate of lung cancer. According to the American Cancer Society, if you have any of the following problems, see a doctor right away:

A cough that does not go away
Chest pain
Hoarseness
Weight loss and loss of appetite
Bloody or rust-colored sputum (spit or phlegm)
Shortness of breath
Fever without a known reason
Recurring infections such as bronchitis and pneumonia

Risk Factors

Tobacco smoking is by far the leading risk factor for lung cancer. Tobacco smoke causes more than 8 out of 10 cases of lung cancer, according to the Cancer Society.

In addition to cigarettes, there are many other risk factors for lung cancer: a family or personal history of lung cancer, exposure to cancer-causing agents in the workplace or the environment, aging and lung scarring which results from some types of pneumonia.

SMOKING

Smoking is by far the leading risk factor for lung cancer.

Tobacco smoke causes more than eight out of ten cases of lung cancer.

The longer a person has been smoking and the more packs per day smoked, the greater the risk.

DON'T SMOKE

People who dont smoke but who breathe the smoke of others also have a higher risk of lung cancer.

Non-smoking spouses of smokers have a 30 percent greater risk of developing lung cancer than do spouses of nonsmokers.

Workers exposed to tobacco smoke in the workplace are also more likely to get lung cancer.

ASBESTOS

People who work with asbestos have a higher risk of getting lung cancer.

If they smoke as well, the risk is greatly increased.

RADON

Is radioactive gas made by the natural breakdown of uranium, which is found at higher-than-normal levels in the soil in some parts of the United States.

Radon cant be seen, tasted or smelled.

Radon can become concentrated indoors and create a possible risk for cancer.

Survival Rates

The 5-year relative survival rate for all stages of lung cancer combined is only 15 percent. This has improved slightly in the last few years, according to the American Cancer Society. For people whose lung cancer is found and treated before it has spread to lymph nodes or other organs, the average 5-year relative survival rate is about 49 percent. However, only 16 percent of people with lung cancer are diagnosed at this early, localized stage. If the cancer has spread to lymph nodes, the 5-year relative survival rate is 17 percent.

Treatment Options

In recent years, much progress has been made in treating lung cancer with surgery, radiation therapy, and chemotherapy. Surgery has been improved, and more is known about the best way to combine drugs to treat different types of cancer.

SURGERY

The type of lung cancer surgery a doctor performs depends on the location of the tumor in the lung.

Some tumors are inoperable (cannot be removed by surgery) because of the size or location and some patients cannot have surgery for other medical reasons.

CHEMOTHERAPY

Chemotherapy may be used to control cancer growth or to relieve symptoms.

RADIATION THERAPY

Also called radiotherapy, involves the use of high-energy rays to kill cancer cells.

Radiation therapy is directed to a limited area and affects the cancer cells only in that area.

PHOTODYNAMIC THERAPY

This type of laser therapy involves the use of a special chemical that is injected into the bloodstream and absorbed by cells all over the body.

(More about treatment options)

Types Of Lung Cancer

SMALL CELL LUNG CANCER

About 20 out of every 100 lung cancers diagnosed are small cell lung cancer.

The cancer cells are small cells that are mostly filled with the nucleus (the control centre of cells).

Small cell cancer can also be called "oat cell" cancer.

This type of cancer is usually caused by smoking.

It's not common for someone who has never smoked to develop it.

Small cell lung cancer often spreads quite early so doctors often suggest treatment with chemotherapy rather than surgery.

NON-SMALL CELL LUNG CANCER

Three types : Squamous cell carcinoma, Adenocarcinoma, large cell carcinoma.

These are grouped together because they behave in a similar way and respond to treatment differently to small cell lung cancer.

SECONDARY CANCER

Is cancer that has spread from somewhere else in the body.

There are quite a few different cancers that can spread to the lungs, including breast cancer and bowel cancer.

More Information:

National Cancer Institute: Lung Cancer
American Cancer Society: All about Lung Cancer
MedlinePlus.gov: Lung Cancer Resources