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SMOKING: The Number One Cause Of Lung Cancer Essay, Research Paper
SMOKING: THE NUMBER ONE CAUSE OF LUNG CANCER
Lung cancer is a disease in which a primary cancer (the original site where
the cancer occurred) develops in the tissue of the lungs. Lung cancer was first
described by doctors in the mid 1800’s. At the turn of the century, it was still
considered a rarity; that has changed dramatically. What has not changed is the
difficultly of detecting lung cancer in its earliest stages when it has the
greatest chance of being successfully treated. "Lung cancer is the leading
cause of death from cancer among both men and women, with 168,000 new cases in
1992 and 146,00 deaths" (Winawer 283).
"If you fall into the following categories of people who have been heavy
smokers, you have the greatest chance of being diagnosed with lung cancer: a
male over 60; someone who has smoked one for more packs of cigarettes a day for
20 years or longer; someone who began to smoke before the age of 20 and is still
smoking: a worker in a industrial plant with a high risk material, such as
asbestos, who also smoke. Someone who has persistent or violent smokers cough;
someone who does not smoke but is frequently exposed to unnecessary passive
smoke" (Cooper 114-120).
Numerous studies all over the world have shown a link between cigarette
smoking and lung cancer, as well as other cancers, with an increase in cigarette
smoking followed by an increase of lung cancer. Most of these studies involve
the testing of non-smokers and smokers to see how things can affect them
differently and why. The most common symptom of lung cancer is a cough caused by
a blockage of the air passage to the lung as the tumor grows. Smoking is a major
cause of lung cancer, as well as other cancers and diseases, such as emphysema
and chronic bronchitis. "Smoking is considered the single largest
unnecessary and preventable cause of disease and early death in the United
States" (Napoli 123).
The tobacco plant dates back 7,000 years, originating somewhere between North
and South America. Native Americans may have been the first people to smoke,
chew, or snuff tobacco, and they introduced it to European explorers. In the
17th and 18th centuries it increased in popularity. "In 1761 John Hill, a
physician in London, reported an association between snuff and cancer of the
nose. Thirty years later a doctor in Germany reported on a relationship between
tobacco use and lip cancer." (Altman and Sarg 252). However, it was not
until the 20th century that researchers started seriously investigating the use
of tobacco and its consequences. Studies conducted by scientists in different
countries began appearing in medical journals describing the relationship
between cigarette smoking and cancer and other various diseases.
"The first study in the United States citing conclusive evidence of the
association between cigarette smoking and lung cancer was published in 1950. In
1964, the United States surgeon generals landmark report, "The Health
Consequences of Smoking," was released which showed strong casual
relationship between smoking and lung cancer" (Altman and Sarg). Since that
time researchers have sought and obtained corroborative evidence from many
different sources that cigarette smoking leads to early death. There are now
thousands of studies that detail many different and severe consequences of
smoking.
The only organization that maintains that there is no definite proof of the
hazards of smoking is the Tobacco Institute, created and funded by the tobacco
industry to lobby and coordinate its public relations. When the Tobacco Industry
says something like this it makes you wonder how many of there employees have
gotten lung cancer from smoking there tobacco products.
Research has also been done on the effect of tobacco smoke on non-smokers.
Evidence of its harmful potential is mounting: "According the National
Cancer Institute, non-smokers who live with a smoker are increased risk of
developing lung cancer. Epidemiological studies indicate that the risk for lung
cancer in non-smokers increases 30% if they are married to a smoker; the risk
increases to 70% if the spouses is a heavy smoker" (Altman and Sarg 253).
Involuntary smoking may be partially harmful for specific population groups,
such as children. My opinion is that a child receiving lung cancer because their
parents smoked should be punished in some way, like a big fine, or never be able
to buy another pack of cancer their entire lives. " In 1990 the
Environmental Protection Agency concluded that passive or involuntary smoking
causes 3,000 deaths a year as well as a substantial number of other respiratory
illness or deaths among the children of smokers"(Simmonds 527). The unborn
child of women who smoke, a very special group of passive smokers, weigh less at
birth and are a greater risk for spontaneous abortion, fetal death, and sudden
infant death syndrome. Passive smoking also has some non life threatening but
very annoying side affects, including burning, itching and tearing eyes,
headaches, coughing, irritation, of the nose and throat, allergic reactions and
discomfort from the smell.
"Smoking is responsible for about 400,000 deaths a year in the United
States. The American Cancer Society estimates that cigarette smoking is
responsible for 88% of the lung cancer deaths among women"(Henderson 74).
Smoking is also associated with cancers of the mouth, pharynx, larynx,
esophagus, pancreas, cervix, kidney and bladder. Smoking is a major cause of
heart disease and is associated with conditions ranging from colds and gastric
ulcers to chronic bronchitis, emphysema, and cerebrovascular disease.
More than 2000 chemical compounds have been identified in processed tobacco,
among them, three classes of carcinogens. In 1998 the Surgeon General released a
report on nicotine addiction concluding that cigarettes and other forms of
tobacco are addictive, that nicotine is the drug that causes addiction, and that
cigarette addiction is similar to the addiction of such drugs as heroin and
cocaine.
"In 1989 the surgeon generals report found that prevalence of smoking in
the Untied States decreased from 40% in 1965 to 29% in 1987 adult male smokers
dropped from 42% of the population to 32% of the population, while women smokers
dropped from 32% to 27%"(Winawer 122-125). It is estimated that as of 1990
there were 38 million ex-smokers and 50 million smokers. Smoking rates are still
higher among blacks, blue collar people, and less educated people. Children are
also starting to smoke at earlier ages. Some children are starting as early as
middle school, most start in Junior high if there going to start, at an early
age. In the United States, more than 3,000 teenagers became regular smokers
everyday.
In 1990 the Surgeon General released a report showing that people who quit
smoking, regardless of age, live longer than people who continue to smoke. In
fact, Fifteen to 20 years after quitting, the risk of lung cancer is about that
of a person who never smoked.
Cigarette smoking is unquestionably the major identified cause of human
cancer, accounting for nearly one third of all cancer deaths. Since lung cancer
is the most frequent lethal cancer in the United States, accounting for
approximately 25% of all cancer deaths, it follows that a substantial fraction
of total cancer mortality could be prevented by eliminating tobacco induced lung
cancer. The risk of developing lung cancer depends on both the extent and
duration of smoking. The mortality rate from lung cancer among heavy smokers,
two or more packs a day, is about 20 times greater than for non-smokers.
The next best thing to the prevention of cancer is early detection. The
importance of early detection is due to the progressive nature of the tumor
development. Prior to metastsis, most cancers can be cured by localized
treatments, such as surgery or radiotherapy. Early detection is also critical to
the outcome of the disease. If the earliest stages of cancer could be prevented,
often by the comparatively minor treatment, more lung cancer patients would have
a better chance of surviving the cancer.
Steps taken to detect early stages of a tumor development are referred to as
secondary treatment and prevention. For some types of cancer, such as lung
cancer, regular visits to the doctor is a way of detecting it early. "After
nearly 20 years of practicing medicine at Memorial Sloan-Kettering, Dr. Diane
Stover still shakes her head and ponders that question every time she prepares
to tell a patient he or she has lung cancer"(Cooper 117). The lungs are the
primary component of the respiratory system, occupying most of the cavity and
flanking the media stinum, the chamber that houses the heart. A thin two ply
membrane, the pleura, envelopes each lung, an organ made of millions of tiny air
sacs, giving it the appearance of spongy, pinkish-gray tissue laced with an
intricate network of blood vessels. The left lung is divided into sections; the
slightly, larger right lung, into three.
When you inhale, air travels through the nasal and oral passages into the
throat, through the larynx and the trachea, or windpipe, and into the lungs by
way of two tubes called the bronchi. These in turn feed the bronchioles and
culminate in the alveoli; the diaphragm, a dome shaped muscle bordering the
underside of both lungs, contracts rhythmically and enables them to expand.
During exhalation the diaphragm shifts black into place, deflating the lungs and
forcing air outward.
In the lungs oxygen is exchanged for carbon dioxide and other waste gases
through the thin walls of the capillaries and the alveoli, like most other
functions of the human body, respiration is a remarkably complex, finely
balanced process. Lung cancer develops when a carcinogen, be it asbestos, radon,
cigarette smoke or some other initiator, damages a cell’s DNA. Half of all lung
tumors contain a defective tumor suppressor gene, called p53 by molecular
biologists, that permits uninhibited cell growth.
Lung cancer rarely produces symptoms until it is well entrenched in the lung.
By that time it may have metastasized to other parts of the body. Fatigue, the
most frequently seen sign, is often shrugged off and not considered a serious
problem. The same is true of another common warning, coughing, which is caused
by an irritation of the bronchial lining or a tumor blocking an air passage.
Many smokers are so used to hacking and wheezing, they dismiss this as
"smoker’s cough" and neglect to see a doctor at this stage.
"Because fewer than one in five lung cancers are detected early, the
disease frequently runs a deadly coarse. Complicating matters, notes Dr. Stover,
‘Most of these patients have underlying chronic obstructive pulmonary disease
from smoking,’ which limits therapy options"(Winawer 23). The longer a
person goes with out tobacco, the more the lungs will heal themselves.
Eventually the risk of pulmonary cancer will approach that of a non-smoker.
The way you diet can also affect your health greatly. A number of human
studies have examined fruits and vegetables possible protective effective
against lung cancer in smokers and non-smokers. One theory hold that vitamins C,
E and beta-carotene, all anti oxidants, demobilized and eliminate the
free-radical molecules that can impair lung-cell DNA and promote tumor growth.
More research is needed though, to pinpoint just which of there are many
vitamins and nutrients could possibly lower risk. How many fruits and vegetables
reduce the risk of lung cancer?
After seeing how much damage smoking can cause, you would think this world
would not even manufacture tobacco products. But people are so addicted to the
nicotine, they cannot make themselves quit smoking, even if it would mean saving
their lives. They have made smoking a habit a very bad habit that is hard for
them to quit that habit. The smart smokers do quit, but the less fortunate ones
keep on smoking. Smokers should realize they are not just hurting themselves but
everyone around them.
According to the "Annual Report to the nation on the status of cancer,
1973-1996, with a special section on lung cancer and tobacco smoking"(Seppa
310). The incidence of new cancer cases and the rate of deaths from all cancer
cases and the rate of death from all cancers combined decreased in the United
States between 1990 and 1996. The American Cancer Society, The National Cancer
Institute and the Centers for disease control and Prevention released the
report, which was published in the April 21, 1999 issue of The Journal of the
National Cancer Institute.
"The incidence rate (number of new cancer cases per 100,000 persons) for
all cancers combined declined an average of 56% per year between 1990 and 1996,
with the greatest decrease after 1992, the year in which incidence rates peaked.
From 1990 to 1996, the death rate from cancer has fallen an average of 0.6
percent per year. The may reason for this decline was because so many smokers
had realized if they want to live longer and healthier life they should quit
smoking"(Brown 7).
"The greatest decline in the incidence rate was seen among men, who
overall have higher rates of cancer than women. From 1990 to 1996, the overall
decline in the incidence rate was greater for men than for women, with the
largest decrease seen among men who were 24 to 44 years of age and those 75
years or older" (Henderson 74).
Among women, the largest decrease was seen those 35 to 44 years of age and
those 85 years and older. The death rate decreased among men of all ages, with
exception of those 85 years of age and older; this decrease actually in overall
decline. The death rate decreased among women younger than 65 years of age.
Their report also included a special section on lung cancer and tobacco use.
Lung cancer accounts for 25 percent of all cancer deaths each year, causing more
deaths than any other type of cancer. According to the study, from 1990 to 1996,
incidence rates of lung cancer among men decreased and average of 2.6 percent
per year, and death rates decreased by about 1.6 percent per year.
7b3
Altman, Roberta., and Sarg, Micheal. Dr. The Cancer Dictionary. New York
City: Facts
on File, 1992. page 252.
Cooper, Geoffrey M. Ph. D. The Cancer Book. Boston: Jones and Bartlett
Publishers
International, P. 1993, pages 114–120.
Winawer, Sidney J. M.D. Cancer Free. New York: Simon and Schuster P. 1991
pages
23-26, 117-125, and 234-284.
Brown, Ellen, "Waging War on Lung Cancer." FDA Consumer May 1999:
7.
Seppa, N. "Therapy pits useful gene againist tumor." (gene therapy
for lung cancer)
Science News May 15, 1999 v155 i20 page 310.
Napoli, Maryann. "Early Dection of Lung Cancer– Caution Advised.
HealthFacts
August 1999 page 123.
Simmonds, Peter. "Managing patients with Lung Cancer." (Statisical
Data included)
British Medical Journal August 28, 1999 v319 i7209 page 527.
Henderson, Charles W. "Study Reveals Gender Affects Cancer
Development." Cancer
Weekly Plus May 3, 1999 pages 74.