Nov 15, 2013

200 Types of Cancer

The reason is that there are over 200 different types of cells in the human body with each of these having the potential to become cancerous. Cancer can develop in any of the over 60 organs in the body. Cancers are named for the part of the body where it started and the type of cell that has become cancerous. All cancers start because abnormal cells grow out of control. There are two general categories of cancer. Carcinomas are cancers that develop on the surface linings of the organs. Sarcomas are cancers that develop in the cells, and they affect solid tissues, such as muscle and bone. They can also develop in the blood vessels. Cancer tumors can either be malignant or benign.

Normal healthy cells divide and die as they should. The average number of times normal healthy cells divide is known as the Hayflick Limit. It was named after Dr. Leonard Hayflick, who in 1965 noticed that cells divide a specific number of times before the division stops. The average was between 40-60. (There is one woman who had tissue in her body that could divide apparently forever: The Woman with Immortal Cells)

If you took every cell in your body, at the time you were born, and accounted for all the cells they would produce and multiplied that number by the average time it takes for those cells to die, you get what is known as the ultimate Hayflick limit or the maximum number of years you can theoretically live. This is how researchers come up with the theoretical life limit of 120 years.

For the first time since the government began collecting mortality data early in the last century, cancer death rates began to decline in 1993. It significantly declined from 1994 to 1998 with a non-significant decline from 1998 to 2001 and falling death rates from 2001 to 2008. In 2008, the death rate for all cancers was 175.67 per 100,000 people in the US. Cancer is not contagious.

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