Lung cancer occurs when cancerous cells develop in the lung's tissue. It is the most common fatal cancer among men and women, and it is the number one killer in the world. Lung cancer has the highest mortality rate out of all the cancers combined. People with risk factors for developing the disease should have regular checkups to determine if they are cancer free.

Family history of the disease can be a warning sign that lung cancer may run in your family and that you should be checked more often. Some risk factors for lung cancer can also include age, sex, or race and are called non-modifiable factors because the person can't change them. Some lesser-known symptoms to watch out for include:

• Shoulder or upper back pain caused by a tumor pressing into the lung lining

• Swelling of the face and neck caused by change in circulation brought on by the tumor

• Having frequent bouts of pneumonia or other lung infections

When tumors press against blood vessels, the fluids cannot travel as well through the body, and these fluids build up in the neck and face and often times the hands and feet as well. Having frequent periods of lung infections or pneumonia can also be a sign of lung cancer as the cells of the tumor trap and hold bacteria.

There are two types of lung cancer - Non-small cell and small cell. Non-small cell cancer is usually associated with people who smoke and is the most common form of diagnosed cancer. Small cell lung cancer - or oat cancer - is rarer, but is also caused by smoking. Non-small cancer is more common and spreads much slower than small cell cancer. Three main types of this cancer are named for the cells where they tend to develop. These are Squamous cell carcinoma, adenocarcinoma, and large cell carcinoma. Small cell lung cancer tends to grow and spread much more quickly than non-small cancer and can quickly spread to other areas of the body. Both types of cancers react to treatments in different ways.

Some substances that can cause lung cancer are familiar to you while others may come as a surprise. Cigarette smoking is one of the causes. How often have you heard that over the years? It is far more likely that someone who smokes will develop lung cancer than someone who doesn't smoke. The age at which the person began smoking, and the length of time they've been smoking are also factors in the development of the disease. Even people who don't smoke themselves can be exposed to the second-hand smoke and develop lung cancer over time. Some other substances that can cause lung cancer include Radon exposure and Asbestos exposure.

It's very important to follow up with your doctor if you suspect that you may have some symptoms. The sooner the disease is discovered and treatment is begun, the sooner you'll be well again. Regular checkups can make sure that any cancer is caught in the early stages and can be treated quickly and effectively with a variety of treatments. Physical exams, x-rays, and blood or urine tests may be required to check thoroughly.