РефератыИностранный языкSkSkin Cancer Essay Research Paper Skin CancerAbout

Skin Cancer Essay Research Paper Skin CancerAbout

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 ultr

aviolet 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 is a change on the skin, such as a growth or a sore that won’t heal.


Sometimes there may be a small lump which can be smooth, shiny or waxy


looking and can be red or reddish brown(Seely Stephens Tate 149) . Not all


changes however, are skin cancer. But all changes in one’s skin should be brought


to the attention of a doctor for a medical evaluation.


Treatment involves removing the lesion. The goal is to remove or destroy the


growth completely with as little damage as possible to healthy tissue. Types of


surgery for skin cancer include cryosurgery, destruction of the area by freezing it,


or laser surgery, curretage, and electrodessication, which uses a spoon-like blade


to scoop out the growth. Chemotherapy uses drugs to kill cancer cells. In skin


cancer, chemotherapy is often given as a cream or lotion to place on the skin to


kill the cancerous cells.


Even after successful treatment, people continue to remain at risk of developing


it again in the future. The most important thing that they can do is to protect


their skin from ultraviolet ray exposure and making sunscreen, with a high SPF


value, a life-long habit.


Bibliography


Ingraham Ingraham. 1995.Introduction to Microbiology. Wadsworth


Publishing.California.447.


Seely, Stephens, Tate. 1998. Anatomy and Physiology 4th edition.Mcgraw-Hill


company.145.447.


Funk & Wagnall.1984. Funk & Wagnalls Standard Desk Dictionary.Donnelly &


sons company.408.


Encarta Encyclopedia 98.1998. Encarta Encyclopedia 98. Microsoft. Cdrom Disc


1.


Barnes-Savarney, P.1995.Science Desk Reference. Macmillian publishing. New


York. 177


Ladies Home Journal.March 1999. Protecting your skin.33.

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