Essay/Term paper: Cancer: the costs, causes, and cures

Essay, term paper, research paper:  Medicine

Cancer: The Costs, Causes, and Cures


Cancer is a major killer of people all around the globe. We do not have a
definite cure, but the amount of research done on this one disease costs on the
average of $1.2 billion dollars annually, and $20 billion annually in care of
cancer patients.

What is Cancer?

Cancer is a broad ranging term that is used by many people, including medical
professionals such as doctors. Cancer, in its most fatal and aggressive form, is
of a larger class of diseases known as neoplasms. There are two forms of a
neoplasm: benign or malignant. A benign neoplasm is encapsulated, or surrounded,
so that it's growth is restricted, whereas a malignant neoplasm is not closed in.
Malignant tumors grow much more quickly than benign forms and spread into the
surrounding normal tissue, and virtually destroy it, (Grolier Electronic
Encyclopedia, Cancer).

The question is, what exactly is cancer? Cancer, is the break down and mutation
of the cells of the body, when the DNA (Deoxyribonucleic Acid) sequences in
those molecules are disrupted and errors form in the structures, (Grolier,
Genetic Code). This mutation spreads through surrounding tissue until it
disrupts major systems in the body (such as respiratory, digestive and waste
management) cause that system to fail.

What causes Cancer to become active?

Since it is believed that almost all people have some type of cancer in their
body, (although benign), any person that comes in contact with a carcinogen,
(any cancer-causing agent), will cause these benign cells to become malignant.

It is when the cells become malignant, that cancer actually occurs. Cancer, in
this context, can be caused by many different agents; chemical, biological or
physical.

Chemical Agents

Chemicals that can cause a benign cell to become active include things such as
complex hydrocarbons, aromatic amines, certain metals, drugs, hormones, and
naturally occurring chemicals in plants and molds. Hydrocarbons and nitrosamines
can be found in cigarette smoke and may contribute to the condition called "lung
cancer". Other chemicals that seem to cause incidents of "bladder cancer", such
as 2-naphthylamine, were used in the dye industry for dyeing cloth, but when a
number of cases of cancer turned up, its use was discontinued. Vinyl Chloride, a
chemical gas, has also appeared, seeming to cause "liver cancer" ,(Grolier,
Cancer)

Drugs, such as some cancer-treating alkylating agents, are also carcinogens.
These agents are used to break the DNA strands in the cells, thereby killing the
cells, but it also effects the cells surrounding the tumor, actually making them
malignant. When these chemicals are used to treat cancer in this way, they must
in exact proportions for each person and if the dosage is incorrect, the
chemical will create a cancerous effect. Estrogens, a group of female hormones,
usually administered to women after menopause seem to cause an increased
incidence of cancer of the uterus. This has been alleviated today by
administering estrogen in combination with progesterone. Certain salts, that
contain arsenic, are suspected to casually relate to cancer of the skin and
liver, (Grolier, Cancer).

The suggestion that cancer is caused by an alteration of DNA within the benign
cell, was proposed by James and Elizabeth Miller in the 1960s, who demonstrated
that chemical carcinogens must be metabolized and broken down so that they may
interact with the DNA of the cells in question, directly, (Grolier, Cancer).

Biological Agents

Our own bodies, in conjunction with parasites found in different parts of the
world, have been related to the causes of many types of cancer. Some of the most
clearly established biological agents are the oncogenic (cancer-causing) viruses
that commonly cause the formation of neoplasms in lower animals have been linked
to some human cancers, and at least one has been definitely proven to cause
cancer of the blood (leukemia), (Grolier, Cancer).

Physical Agents

High energy and ultraviolet radiation are two of the major causes of human and
animal cancer. It has been proven that there is a relation between the sun's
ultraviolet rays, and the development of skin cancer in humans. Cancer caused by
radiation include just about every known variety, including leukemia, cancer of
the thyroid, breast, stomach, uterus and bone, (Grolier, Cancer).

It has also been suggested that electromagnetic fields can pose a risk of
contracting cancer when the field strength is extremely high. Power lines
running through cities and through the country, including large hydro towers
that carry power through the countryside, create such electromagnetic fields.
These fields are strong enough, in most cases, to light a oi= scent tube that a
person is holding just by walking underneath the power lines. In several
instances in the United States, especially in Washington and New York, the
fields are so strong that people are fearing that the exposure may be hurting
their children, (Fortune, p. 80).

It is recommended that pregnant women do not use electric heating blankets for
extended periods, (sleeping, etc.), as the blankets create a low electromagnetic
field that may actually creating cancer in the fetus during development.

Inherited Cancer

As was stated earlier, everyone has cancer, although benign. It is passed from
one generation to the next, and depending on the amount of carcinogens the
previous generation has had contact with, will be relative to the risk placed on
their offspring. Some carcinogens can be stored in the body and not used, and
can be replicated in the next generation because the body has the ability to
create DNA and RNA sequences that represent their carcinogens.

This is not necessarily the cause for inherited cancer, nor why it affects some
offspring and not others. It has been shown that cancer can remain dormant in
several generations, and then suddenly become active in a healthy generation.

Stages

Cancer does not jump out of the woodwork in a day; in most cases, it takes a
long time for cancer to become detectable, depending on the type, and where it
is growing. It has shown that cancer detected in the earliest stages of its
growth is far easier to stop, and so the American Cancer Society has begun to
promote public awareness of the seven warning signs to look for:

(1) a change in bowel or bladder function; (2) a sore that does not heal; (3)
unusual bleeding or discharge; (4) a thickening or lump in the breast or
elsewhere; (5) indigestion or difficulty in swallowing; (6) an obvious change in
a wart or a mole; and, (7) a nagging cough or hoarseness. Should anyone exhibit
any of these symptoms, they should see a physician immediately. (Groiler,
Cancer)



Initiation and Promotion

One of the characteristics in the development of cancer in an organism is the
amount of time between initial exposure to a carcinogen, and the actual
development of a malignant cancerous tumor:

Beginning in the late 1940s, a number of investigators defined the early stages
in the development, or natural history, of cancer. In a classical experiment
pertormed on the skin of mice, a single application of an agent induced no
neoplasms, but when it was followed by several applications of a second agent,
termed the promoter, neoplasms developed. (Grolier, Cancer)

It was found that initiation by the first agent is irreversible once the
reaction has begun, however, it was also noted that if the addition of the
promoter was done in several doses, over a long period of time, no neoplasms
would occur, even though the actual dosage of the promoter was the same. In
humans for instance, alcoholic beverages, dietary fat, and many of the
components of cigarette smoke are shown to be effective promoting agents.
(Grolier, Cancer)

Progression

Once a tumor has been created by initiation and promotion, it can progress from
a benign to malignant form, or from a slowly reproducing tumor to a rapidly
growing malignant tumor. This progression has been shown to be related to the
number of abnormalities within a cell's DNA. The cells surrounding the tumor
will be assimilated into the tumor as it grows. It has been shown that tumors
can suddenly stop growing, and then resume its growth at a later time. There is
no evidence as to why this happens, and scientists believe it is related to
unused portions of the DNA strands in cells that have been transformed into
instructions regarding the tumors growth.

Treatment

Treatment of cancer seems to be more of an art than a science at the moment.
Especially in the areas of surgery, radiation treatment, chemotherapy and other
areas.

Surgery

Surgical removal of a cancer from the body is the oldest and sometimes most
effective means of disrupting and stopping cancer growth. Surgery can be used to
remove malignant or benign tumors within the body, although the practice of
removing benign tumors is not practiced due to the possibility of making it
active. Removal of complete malignant tumors is often successful in halting
cancer growth in that particular region, when followed by radiation therapy. It
is also possible to remove parts of tumors, to reduce the amount of cancerous
tissue in the body as a whole. The one major drawback to surgery is that quite
often a tumor is not accessible to a surgeon, or it may be attached to a major
organ of the body, in which removing the tumor may cause serious side affects
and even death. So long as a cancerous tumor has not spread to a major organ or
tissue, the removal will be a safe and will be successful in most cases.

Surgical removal of a cancerous tumor may give people the extra months or years
to carry out things they want to do, especially for those people who can not be
totally free of cancerous tissue. Surgery to remove a tumor may give people the
comfort in which to live out their lives, even though it may not be the complete
solution, (Encyclopedia Britannica, p. 541 )

Radiation

Radiation treatments are normally conducted after surgery if there was a large
affected area, or treatments can be used on small tumors when surgery is not
possible. Irradiating a large area of the body for a large tumor can create
other types of cancer within the body.

Treatments can be carried out using gamma rays that are emitted by Cobalt-60, a
radioactive element, by focusing high powered X-rays (many times the strength of
the normal Xray used to scan the body) or particles (electrons and neutrons).
Although some of the surrounding cells are killed in the radiation process, the
effect is minimized by shielding surrounding areas with dense materials, such as
lead and gold. The source of the radiation and the sensitivity of the tumor are
relative to the overall effect on the tumor.

Radiation treatments are extremely efective on leukemia and carcinomas (solid
tumors which forms the skin and linings of most glands and organs) as they are
extremely sensitive to the radiation.

If radiation therapy is unsuccessful in the first few treatments, it is unlikely
to have any significant impact on the cancer after this stage, and may cause
more damage than it does good. Chemotherapy

Chemotherapy

Chemotherapy is the process by which chemicals are administered into the body to
fight and destroy cancerous cells and tumors. At present, at least 10 types of
human cancer can be treated and cured by chemotherapy alone or in conjunction
with surgery and/or radiation, (Britannica, p. 558).

Chemotherapy has been proven successful against some strains of cancer such as
lymphocytic leukemia in children, Hodgkin's Disease, sarcomas (connective tissue
such as bone and fat) and kidney tumors. Chemotherapy is usually not a complete
cure, but has helped to drastically increase the useful lifetime of many
patients with these diseases.

There is one major point to note about chemotherapy, and that is that it
has been shown that some chemicals used in the treatment of cancer will actually
create other forms of cancer, or speed the growth of those already malignant, if
dosages or administration of the chemicals is incorrect:

Compounds that have been effective in the chemotherapy of human cancer include
certain hormones, especially the steroid sex hormones and those from the adrenal
cortex; antibiotics produced naturally by a variety of microorganisms; plant
alkaloids, including vinblastine and vincristine, derived from the periwinkle
flower; alkylating agents--chemicals that react directly with DNA; and
antimetabolites, which resemble normal metabolites (metabolic compounds) in
structure and compete with them for some metabolic function, thus preventing
further utilization of normal metabolic pathways. (Grolier, Cancer)

It has also been noted that as chemotherapy damages some of the
surrounding tissue around a tumor, chemotherapy can have some serious side
effects. Some patients develop severe nausea and vomiting, become very tired,
and lose their hair temporarily. Special drugs are given to alleviate some of
these symptoms, particularly the nausea and vomiting, (Compton's Multimedia
Encyclopedia, Cancer - Chemotherapy).

Immunotherapy

hile still a rather new form of treatment, it is looked as having great
promise. Immunotherapy is where the body's own immune system is used to combat
the neoplasms situated in the body, with the help of "engineered" antibodies
that are added to the patients immune system. The immune system will then
replicate the antibody and send it out to destroy any cancerous cells matching
the DNA and RNA sequences it was designed to track, while attaching itself to
healthy cells to prevent assimilation by cancerous cells. This process has
worked on a single-case basis with good results, but it is expected to be a
while before its use is wide spread. (How it Works, p. 415)

Recent Trends

It has come about recently, that therapies combining less radical forms of
surgery, with radiation, chemotherapy and/or preventive medicine have been used:

Such therapy has been especially useful in the treatment of breast cancer, where
the traditional radical mastectomy, involving removal of the breast, lymph nodes,
and parts of the arm and chest muscles is becoming less common. It is being
replaced by relatively simple surgery involving removal of only the lump itself
or the breast, followed by chemotherapy or the use of preventive drugs. An
example of the latter is tamoxifen, an anti-estrogen that prevents the growth of
cancer cells with little or no toxicity to the host and remaining normal cells.
(Grolier, Cancer)

Remission

Rehabilitation is an important and ongoing process after having cancer
treatment(s) of any kind. The majority of cancers are considered cured if there
is no reoccurrence within five years after the last treatment. Other types of
cancer are required to be monitored for ten years after treatments to be sure
that no reoccurrence is to happen. It is also to be noted that many types of
leukemia may seem to be none existent for several years, and then it may appear
again. Also, it is generally harder to treat a reoccurrence such as this than in
the original case.

Present and Future Research

Cancer is an elusive and stubborn disease that can be turn up in almost any
system of the body. With this in mind, it must be known that there must be a
common reason for malignant cancer cells to continue to plague a large
percentage of our population:

In 1983, for example, U.S. and British researchers determined that at least two
genetic changes may be needed to transform cells into cancerous cells under
laboratory conditions: one stage enables the cell to grow indefinitely; the
other stage enables the cell to ignore signals from surrounding cells that would
otherwise halt its growth. Also, because the means to identify most of the
carcinogenic agents in the environment are now available, a major program of
cancer prevention is within reach. (Grolier, Cancer)

With this theory in mind, it will be relatively easy to control cancer once we
are intelligent and wise enough to know how to directly manipulate the DNA
sequences in cells, and place that information in the bodies of the patients in
question. It will be a glorious day when we can alleviate cancer from this world,
or will it?

My Thought and Ideas about the Future of Cancer

In the present day, our technology increases ten-fold each year. We are able to
find out more, faster and more efficiently than in any other time in history.
With our new knowledge that is forthcoming, I would predict the end of most
major diseases early in the next century. Once we are able to read and modify
the data and instructions found in our own DNA, we can directly access the way
we as living beings will grow and evolve. However, we will have another problem,
and that is of population. If there are no diseases to disrupt the growth of our
population on this planet, we will soon overcrowd, and we may not yet have the
technology to leave this world. However, I think we will still be better off
without cancer.

References

Tetzeli, R. (1990). Can Power Lines Give You Cancer? FORTLINE Magazine, 49, 80-
85

Pitot, H.C. M.D. et al. (1992) Cancer. Grolier Electronic Encyclopedia,1992 ed.
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phrases: CANCER, GENETIC CODE, DNA, RNA

Clarke, D. & Dartford, M. ( 1992). Cancer Treatment. How It Works: The New
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Science and Invention Encyclopedia, 414-418

Abeloff, M.D. et al (1991) Cancer. Encyclopedia Britannica: Macropedia, 534-542

Drill, V.A. et al (1991) Drugs and Drug Action - Chemotherapy. Encyclopedia
Britannica:

Macropedia, 553-560

American Cancer Society et al (1992) Cancer. Compton's Multimedia
Encyclopedia,1992 ed.

Search phrases: CANCER, CHEMOTHERAPY, GENETICS