Diseases and Disorders - Leukemia

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CHAPTER ONE
What Is Leukemia?
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eukemia is a type of cancer that has afflicted people and animals for thousands of years. Anthropologists discovered evidence of the earliest known human case of the disease in a
skeleton found at Dakhla, an area of Egypt’s western desert
that was a thriving political and economic center from 36 B.C.
to A.D. 450. Scientists determined that the skeletal remains contain certain characteristic pits and holes unique to the bones
of people with leukemia.
Other ancient evidence of leukemia comes from bone marrow deoxyribonucleic acid (DNA) extracted from a fifteenhundred-year-old mummy found in the Atacama Desert of
Chile. Scientists discovered that the DNA contains a virus that
is now known to be associated with a type of leukemia called
adult T-cell leukemia. They concluded that the virus probably
caused adult T-cell leukemia in the person whose remains
were found in the Atacama Desert.
First Identified as a Disease
Although it has existed throughout human history, leukemia
was not really understood as a distinct disease until doctors
had the tools to view the microscopic cells that make up living
creatures. While many forms of cancer consist of tumors that
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What Is Leukemia?
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can be easily seen or felt in specific areas of the body, leukemia
affects the blood and blood-forming tissues. It can only be detected using a microscope and other tools that allow physicians to see or chemically test for its characteristics.
German pathologist Rudolf Virchow first identified leukemia
as a disease in 1845 after using a microscope to view the blood
of several patients with the same unexplained symptoms.
Virchow noticed that the blood contained an overabundance of
white blood cells and fewer than the normal amount of the other
types of blood cells, so he named the disorder weisses blut,
which means “white blood” in German. The English word
German pathologist Rudolf Virchow first identified leukemia as a
disease in 1845.