Where Does Cancer Come From

Like many diseases, cancer is merely an alteration of normal biological processes. It is not "caught" like the common cold but developed in the body. The basis of the cancer is the very foundation of life itself, cell reproduction. As a rule of nature, all cells must come from existing cells. In order to make a new cell, an existing cell grows in size, makes an exact copy of its DNA, and then divides into two identical cells, each with a complete copy of DNA. These two cells can then grow in size, copy their DNA, and divide, creating four cells total, and so on (Figure 13.6).

Throughout life, all tissue in the body grows in this manner until its genetically predetermined size is realized. Thus the brain and other organs will get only so big under normal conditions. At this point there

Lung

Colon and rectum Prostate Pancreas Leukemia Liver Esophagus Non-Hodgkin lymphoma Urinary Bladder Kidney All others

Lung I

Breast I

Colon and rectum I

Pancreas I

Ovary I

Leukemia |

Non-Hodgkln lymphoma I

Uterine corpus I

Myeloma I

Brain I

All others I

Figure 13.5 Estimation of total and type of cancer in 2006 in the United States.

are two possible scenarios. One scenario is that the current cells will exist for extremely long periods. For example, once tissue such as the brain, pancreas, and adrenals reach their intended size, their cells may exist for several decades or even throughout life. These cells simply are arrested in their ability to grow and divide.

The second scenario is that cells of a particular organ or tissue will continuously undergo turnover. The term turnover describes the balance between cells being broken down and those being made. New cells are constantly being made to replace cells of the same type that have a limited life span. The replaced cells are either broken down in the body, such as blood cells, or are removed from body surfaces, such as cells lining the digestive tract and skin cells. Cells that line the stomach and small intestine may have a life span of only a few days, while a red blood cell will live about 4 months.

Figure 13.6 Shows how a single cell can replicate to form eight new cells in three generations.

Source: American Cancer Society.

Figure 13.6 Shows how a single cell can replicate to form eight new cells in three generations.

Source: American Cancer Society.

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10 Ways To Fight Off Cancer

10 Ways To Fight Off Cancer

Learning About 10 Ways Fight Off Cancer Can Have Amazing Benefits For Your Life The Best Tips On How To Keep This Killer At Bay Discovering that you or a loved one has cancer can be utterly terrifying. All the same, once you comprehend the causes of cancer and learn how to reverse those causes, you or your loved one may have more than a fighting chance of beating out cancer.

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