Understandingly, lung cancer starts in the cells of the lungs. It is a disease of uncontrolled cell growth in the tissues of the lung.

Most people know that the lungs are in the chest, one on each side of the heart. The right lung has three main parts, called lobes. The left lung is a bit smaller and has two lobes. The lungs are cushioned and protected by a thin covering called the pleura. The pleura has two layers of tissue: one layer covers the lungs and the other lines the inside wall of the chest. There is a small amount of fluid (pleural fluid) between the two layers of the pleura. So this basically describes what lungs are... but what are they for?

You use your lungs when you breathe. The air you take in through your nose or mouth flows down the trachea (windpipe). The trachea divides into two tubes called the left and right bronchi, which carry air to each lung. Once inside the lung, the bronchi divide into smaller and smaller tubes called bronchioles. Each bronchiole ends in a cluster of tiny air sacs called alveoli. The alveoli take oxygen from the air you breathe in and pass it into the blood for circulation to all parts of your body. The alveoli also remove carbon dioxide from the blood, which is pushed out of the lungs when you exhale. So now you understand the main purpose of your lungs... and now to a closer look at lung cancer.

What most people don't know is that there are two types of lung cancer. The most common type is the non-small cell , also known as (NSCLC). This cancer grows more slowly than the small cell type. While the small-cell grows quickly and often spreads to distant parts of the body.

There is also a rare type of cancer called pleural mesothelioma which is often mistakenly called a lung cancer. But pleural mesothelioma starts in the lining of the lung and is very different from cancer that starts in the lung.

Now for the three types of non-small cancers, which are squamous cell carcinoma, adenocarcinoma, and large cell carcinoma. These account for about 80% of lung cancers, while small-cell (also called oat) accounts for about 20%. The vast majority of all lung cancers are of the carcinoma type.

It's important to understand these three types of cancers because treatment varies accordingly. Non-small cell lung carcinoma for example, is sometimes treated with surgery, while small cell lung carcinoma, usually responds better to chemotherapy and radiation.

Wyatt Schell is a webmaster for the exclusive cancer help resource, Cancer-Help-Treatment. For further information follow the link lung cancer, and receive a FREE book.