August 7, 2007
Introduction to Cancer
Cancer is a condition that occurs when cells in some part of the body begin to grow out of control. Unlike normal cells, the growth of all cancers is not under control and this is what makes them dangerous. Cancer cells utilize all the body’s energy to continue to grow in an endless, uncontrolled fashion.
These cells lose all normal physiological activity and do not respond to any of the body’s normal control mechanisms. As the cancer cells grow and reach a certain size, they spread to other parts of the body. This process, called metastasis, occurs as the cancer cells get into the bloodstream.
Cancer cells develop because of damage to DNA. DNA is the very essence of life and governs all the activities of a cell. In normal cells, when DNA is damaged the cell has the ability to repair it. In cancer, the DNA is not repaired.
The damage to the DNA can occur while smoking, from sun exposure or from other environmental toxins. Different types of cancer can behave very differently. They grow at different rates and respond to different treatments. That is why different people with cancer need different treatments
Cancer is the second leading cause of death in the United States. More than 50% of men and at least 33% of all women in the US will develop cancer during their lifetimes. Today, millions of people are living with cancer or have had cancer. The latest data released by the American Cancer Society indicates that Americans now are at a lower risk of dying from cancer than 2 decades ago.
However, the rate of new cancers is the same as in previous decades. The decrease in death rates has been attributed in part to reduction in tobacco exposure, earlier detection and more effective treatment.
Among women, incidence rates have decreased for:
· colon and rectum cancers
· uterine and ovarian cancers
· head and neck cancers
· stomach cancers
Among men, incidence rates have decreased for:
· colon and rectum cancers
· stomach and lung cancers
· head and neck cancers
However, in men there has been an increased incidence of cancer of the prostate, liver, kidney, esophagus, skin and multiple myeloma. In women, lung and skin cancers are on the rise.
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