What is lung cancer?
To understand lung cancer it is helpful to understand your lungs. Your lungs put oxygen into the blood, which the heart then pumps throughout the body. When blood returns to the lungs, they remove carbon dioxide, a gas your body does not need, from the blood, put oxygen back into the blood, and the process starts over again.
When you inhale, fresh air enters through the nose and mouth and travels to the lungs via the trachea (windpipe). The trachea splits into a right and left main bronchi in the chest allowing the air to travel to the right and left lung. Once in the lungs, the air moves through a series of smaller and smaller tubes called airways. These smaller airways are called bronchioles. At the end of the airways are grape-like sacs, called alveoli. It is here, at the alveoli, where oxygen moves from the alveoli into the blood and carbon dioxide moves from the blood to the alveoli. The blood is pumped out delivering oxygen to all the cells of the body, and the carbon dioxide is exhaled.
Each lung is surrounded by a thin lubricating layer, called the pleura. The pleura is surrounded by the chest wall. The pleura and chest wall are important in protecting the lungs. The dome-shaped muscle under the lungs is called the diaphragm. As the diaphragm contracts and relaxes with each breath, it causes air to move in and out of the lungs.
What is cancer?
Your body's tissues, organs and all the parts of your body are made up of millions of individual cells. These cells have a life cycle of growth, duplication and death. New duplicated cells replace older dying or damaged cells. This is a fine tuned mechanism throughout your life. This mechanism can break down. New cells can be made when they aren't needed. This out of control duplication can result in a tumor. A tumor may be benign or cancerous.
What is a lung nodule?
A lung nodule, or pulmonary nodule, typically is found as a "spot" on your lung. It is usually round or oval in shape. A lung nodule may be easy to find, but it can be hard to find out exactly what it is.
Nodules can be present in your body years before they are discovered by a doctor. Doctors find lung nodules on one out of every 500 chest x-rays. Most nodules (more than 60 percent) are benign or not cancerous. They are usually discovered on a chest X-ray or a chest CT scan.
Benign or non-cancerous nodules can be caused by previous infections or old surgery scars.
Nodules need to be examined and watched closely. Even though most are benign, some are lung cancers. Eighty percent of people who have small lung cancer nodules (1/3 of an inch or less in size and not spread outside the lung) removed live at least five years after the diagnosis. People with larger lung cancer nodules or have lung cancer nodules that have spread outside the lung have a lower survival rate, so early detection is important.
Take the Lung Cancer Quiz to test your knowledge on this disease.
