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Skin Cancer Essay, Research Paper

Skin Cancer

About a million americans will develop skin cancer this year. Skin cancer is

the most prevalent of all cancers, and it’s increasingly on the rise. There are

millions of tiny cells that make up the human body. There are different kinds of

cells, but they all make new cells by a process that involves dividing in half. This

is how old cells are replaced with strong new cells. When a cells divides and

doesn’t do the job that it was intended to do for the body, and then it continues

to divide and makes more of these “useless” cells, and these cells continue to

collect, it is called a tumor.

There are two types of tumors: benign and malignant. The cells in a benign

tumor can “crowd out” healthy cells, even though they can not spread to other,

and healthier, parts of the body (Ingraham 447). However, a malignant tumor is

cancer. A malignant tumor can also “crowd out ” the healthy cells around it, but

in addition to thatt it can spread to other parts of the body and take over the

healthy cells in different areas of the body.

Skin cancer is a disease in which cancer cells are found in the outer layers of

skin. The skin has two main layers and several kinds of cells. The top layer is the

epidermis and it is the layer that is shed most frequently. The inner layer is

called the dermis and is thicker and contains blood vessels, nerves, hair follicles

and sweat glands (Seely Stephens Tate 145).

Cancer spreads by a group of cells or a single cell that breaks away from the

tumor and moves to other parts of the body. Once there, it’ll divide and start

tumors, made of malignant cells, like the ones that mad up the first tumor

(Ingraham 447). When this happens it is called metastic cancer. Metastatic

cancer is defined as the transfer of disease from one part of the body to another,

as in certain types of cancer (Funk & Wagnalls Dictionary 408.) . With many

cancers, the usual first step in prevention is that the affected body part is

removed. However, since a persons skin cannot be removed, in its entirety, this

presents more of a problem to physicians.

Skin cancer is somewhat curable when diagnosed and treated early. And, its

somewhat preventable by avoiding sun and tanning bed exposure. Sunscreen is a

simple, easy, and convenient artificial defense against skin cancer.

There are three main types of skin cancer. Melanoma is the least common,

but most serious because this type is responsible for at least three fourths of the

skin cancer deaths per year (Encarta encyclopedia, cdrom). The other types of

skin cancer are basal cell and squamous cell cancers. These two are referred to as

“non-melanoma” skin cancers. Another rare type of skin cancer, known as

Kaposi’s sarcoma, is rarely seen (Barnes-Savarney, 177).

The most common type of skin cancer is basal cell skin cancer. However,

Melonoma is the fastest growing type of cancer, affecting approximately 32,000

americans in 1993 (Encarta Encyclopedi, cdrom). Melanoma is triggered by

ultraviolet rays from the sun and is signaled by the growth or appearance of an

irregular mole on the skin. The mole may be diagnosed based on its size, shape,

color, or texture, or due to its tenderness or hardness.

Developing skin cancer is a two step process. It involves initiation and

promotion of malignant growth. Since the ultraviolet rays harm the mechanism

for repairing cell damage, one the repair system is impaired, cells become

increasingly vulnerable to injury. Subsequent ultraviolet exposure make it worse,

and can inititate malignancy. After ultraviolet exposure, the repair mechanism in

the body, normally directs damaged cells to “commit suicide”. This is the

explanation for why skin peels after sun tanning and sun burns. However,

previously damaged cells with a malfunctioning repair system escape this process.

Genetic damage accumulates as normal cells die and abnormal ones survive.

It’s been determined that skin does not have to be burned to be damaged, and

such damage accumulates with chronic, everyday exposure (Encarta cdrom).

There are two types of ultraviolet radiation that reach the earth: ultraviolet A

and ultraviolet B. Both contribute to skin damage, and skin cancer, since there

are no “safe” ultraviolet rays. The SPF numbering system on sunscreens was

devised as a guide to protect against sunburn, which is caused mostly by

ultraviolet B rays. Since sunscreens allow one to stay out in the sun longer

without burning, exposure to ultraviolet A rays is increased, and many

sunscreens don’t protect against these rays. While sunscreens protect against

“sunburn”, they don’t necessarily prevent cancer. If a person uses sunscreen to

spend more time in the sun, the skin could collect about the same total exposure

to damaging radiation. This is why most medical journals recommend staying

outo of the sun at midday and wearing protective clothing and hats(Ladies Home

Journal March 1999).

Skin cancer is more common in people with light colored skin who have spent

alot of time in the sunlight (Seely Stephens Tate, 149). Skin cancer can occur

anywhere on the body, but is usually found at places that have a longer exposure

to sunlight such as the arms,face, and neck.

Skin cancer can look many different ways. The most common sign of skin

cancer

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