is the second leading cause of deaths in the United States. One out of two men and one out of three women develop some kind of cancer at some time in their life. Early detection and treatment increase your cances for a cure, so be sure to perform routine self-examinations,have all the recommended screening
tests, and report any suspicious symptoms
to your doctor.
Cancer is a group of diseases characterized by the uncontrolled multiplication of cellls that occurs when genes
that control cell divison or replacement are mutated. These mutations can be inherited, present at birth, or many times they result from environmental factors that damage critical genes.
In normal tissue
, old or damaged cells die naturally before they can become cancerous or cause other problems and are replaced by new cells. In cancer, damage occurs to either the genes that tell cells when to stop dividing or to the genes that tell old or damaged cells when to die. This results in an increase of cells that creates a mass of tissue called a tumor
. As more cells accumulate, the tumor grows.
Cancer can begin anywhere in the body, and can spread through the body in two ways:
- cells from the tumor can invade nearby tissues
- cells from a tumor can penetrate blood vessels or lymphatic vessels and travel to a different part of the body