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Cancer affects 1 in 3 people in the United States. Chances are that you or someone you know has been affected by cancer. Here is some information to help you better understand what cancer is.
You are made up of trillions of cells that over your lifetime normally grow and divide as needed. When cells are abnormal or get old, they usually die. Cancer starts when something goes wrong in this process and your cells keep making new cells and the old or abnormal ones don't die when they should. As the cancer cells grow out of control, they can crowd out normal cells. This makes it hard for your body to work the way it should.
For many people, cancer can be treated successfully. In fact, more people than ever before lead full lives after cancer treatment.
Cancer is more than just one disease
There are many types of cancer. Cancer can develop anywhere in the body and is named for the part of the body where it started. For instance, breast cancer that starts in the breast is still called breast cancer even if it spreads (metastasizes) to other parts of the body.
There are two main categories of cancer:
Hematologic (blood) cancers are cancers of the blood cells, including leukemia, lymphoma, and multiple myeloma.
Solid tumor cancers are cancers of any of the other body organs or tissues. The most common solid tumors are breast, prostate, lung, and colorectal cancers.
What causes cancer?
Cancer cells develop because of multiple changes in their genes. These changes can have many possible causes. Lifestyle habits, genes you get from your parents, and being exposed to cancer-causing agents in the environment can all play a role. Many times, there is no obvious cause.
What is the cancer stage?
When a cancer is found, tests are done to see how big the cancer is and whether it has spread from where it started. This is called the cancer's stage.
A lower stage (such as a stage 1 or 2) means that the cancer has not spread very much. A higher number (such as a stage 3 or 4) means it has spread more. Stage 4 is the highest stage.
The stage of the cancer is very important in choosing the best treatment for a person. Ask your doctor about your cancer's stage and what it means for you.