Lung Cancer Center

Lung cancer

Lung cancer
Lung cancer is the leading cause of cancer death in men and women in the United States. But how do people get lung cancer? And how does it affect the body?

Lung anatomy
The lungs are part of the respiratory system. The lungs absorb oxygen from the air and bring the oxygen into the bloodstream for delivery to the rest of the body. As air enters the body through the nose or mouth, it then passes through the windpipe (trachea) into the lungs and they expand and contract as you breathe in and out. This is how the body gets oxygen and gets rid of carbon dioxide.

The lungs contain many different types of cells. Most cells in the lung are called “epithelial cells” which line the airways and produce mucus to lubricate and protect the lung. The lung also contains blood cells , nerve cells, hormone-producing cells, and structural or supporting cells.

What is lung cancer?
Lung cancer begins when cells in the lung grow out of control and form a lump (also called a tumor, mass, lesion, or nodule). A tumor can be benign (noncancerous) or malignant (cancerous) and can begin anywhere in the lung. A cancerous tumor is a collection of a large number of cancer cells that have the ability to spread to other parts of the body.

Once a cancerous lung tumor begins to grow, it might shed cancer cells. When a cancer cell leaves its site of origin and moves into a lymph node or to a far away part of the body through the bloodstream, it is called metastasis.

These cells can be carried away in blood or float away in the natural fluid, (lymph), which surrounds lung tissue. The natural flow of lymph out of the lungs is toward the center of the chest, which explains why lung cancer often spreads there.

The lungs are full of blood vessels and lymph vessels, giving lung cancer cells easy access to travel to other parts of the body. For this reason, lung cancer may spread to other parts of the body before you experience any signs or symptoms. In many cases, lung cancer may spread before it can even be detected in the lungs.

Types of lung cancer
Lung cancer most commonly begins in the cells that line your lungs. Lung cancers can manifest toward the center of a lung (central carcinoma) or near the pleura of the lung (peripheral carcinoma).The most common types of lung cancer are named for how the lung cancer cells look under a microscope:

Small cell lung cancer - About 13 percent of all lung cancers are small cell lung cancers. This type tends to spread quickly.

Non-small cell lung cancer - This is group of three microscopic types of lung cancer such as adenocarcinoma, large cell carcinoma and squamous call carcinoma. Most lung cancers (about 87 percent) are non-small cell lung cancers. This type spreads more slowly than small cell lung cancer.

Do doctors know what causes lung cancer?  And who is more at risk of developing this very serious disease.  More on what causes lung nodules here.

NEXT: Causes and Risk Factors >>