Essay/Term paper: Cancer

Essay, term paper, research paper:  Biology

Cancer

I.
Cancer is a group of diseases characterized by an uncontrolled growth of
abnormal cells. If the spread of these abnormal cells is not controlled, cancer
can cause death. Most cancers take the form of tumors, although not all tumors
are cancers. A tumor is simply a mass of new tissue that serves no
physiological purpose. It can be benign, like a wart, or malignant, like cancer.
Benign tumors are made up of cells similar to the surrounding normal cells and
are enclosed in a membrane that prevents them from penetrating neighboring
tissues. They are dangerous only if their physical presence interferes with
bodily functions. A malignant tumor, or cancer, is capable of invading
surrounding structures, including blood vessels, the lymph system and nerves.
It can also spread to distant sites by the blood and lymphatic circulation and
so can produce invasive tumors in almost any part of the body.
In 1997, an estimated 1,359,150 people in the United States will be
diagnosed with cancer and 554,740 will die of the disease. Early screening for
cancer is believed to be able to drastically reduce the number of deaths due to
the disease. Knowing what to look for when detecting cancer, as well as knowing
if you are in a high risk population are two of the main factors of early
intervention. Early intervention of cancer has proven to increase survival
rates and lower the length and severity of treatments. Detection and protection
are two types of ambulatory care for cancer that begin before the disease is
ever diagnosed.

II.
Cancer often causes symptoms that you can watch for. These include:
change in bowel or bladder habits; a sore that does not heal; unusual bleeding
or discharge; thickening or lump in the breast or any other part of the body;
indigestion or difficulty swallowing; obvious change in a wart or mole; and
nagging cough or hoarseness. These symptoms are not always warning signs of
cancer. They can also be caused by less serious conditions. It is important to
see a doctor if any of these symptoms occur. Only a doctor can make a diagnosis.
A person shouldn't wait to feel pain because early cancer usually does not
cause pain.
Observation is the most widely available examination for the detection
of cancer. It is useful in identifying suspicious lesions in the skin, lip,
mouth, larynx, external genitalia and cervix. The second most available
detection procedure is palpation. It is particularly valuable in detecting
lumps, nodules, or tumors in the breast, mouth, salivary glands, thyroid,
subcutaneous tissues, anus, rectum, prostate, testes, ovaries and uterus and
enlarged lymph nodes in the neck, axilla or groin.
Internal cancers require an extension of observation through endoscopes,
x-rays, magnetic resonance imaging, and ultrasound. Laboratory test, such as
the Pap smear, and occult blood testing of the feces have also proven helpful
for some of the cancers. However, concerns regarding effectiveness and yield
play a particularly important role in decisions to screen for cancers not easily
responsive to earlier detection through physical examination. The performance
of these tests is usually measured in terms of sensitivity, specificity, and
positive and negative predictive values.
The type, periodicity, and commencement of screening in high-risk
populations for most cancers reflect the judgment of expert practitioners rather
that evidence from scientifically- conducted test. Some individuals are known
to be at high risk for cancer, such as those with a strong family history of
cancer. Physician judgment is needed in such circumstances to determine the
most appropriate application of available screening methods. Once the high-risk
person is identified, is counseled appropriately, and regularly undergoes
screening procedures, the benefits of early detection and treatment are
available to this person, yielding a proven higher chance of recovery. Those
people considered high risk should take extra precautions when attempting to
detect cancer.

III.
Important facts that a person should know about how to protect against
getting cancer include: not using tobacco products; eating at least five
servings of fruits and vegetables each day; if you are a woman, getting a
mammogram, pelvic exam and Pap test every year; getting tests done as you get
older for cancers of the colon and rectum; if you are a man, getting early
detection tests for prostate cancer, avoiding too much sunlight by wearing
protective clothing and sun screen; and avoiding unnecessary x-rays. If a
person does have cancer, it is wise to find out what the treatment choices are
and which are best suited for that person. Before getting treatment, it is
advisable to get a second opinion from another doctor. These are all forms of
protection that can be done by an ambulatory basis.

IV.
Four basic forms of treatment for cancer are currently practiced. These
are surgery, radiation therapy, biological therapy and chemotherapy. All but
surgery can be performed on an outpatient basis. The physician may use one form
of therapy or a number of different forms in order to produce the desired
results.

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A.
Radiation therapy is one of the major ambulatory treatment modalities
for cancer. Approximately 60% of all people with cancer will be treated with
radiation therapy sometime during the course of their disease. Its
effectiveness as a treatment for cancer was first reported in the late 1800s.
Advances in equipment technology, combined with the science of radiobiology,
have led to today's highly sophisticated treatment centers. Radiation therapy
can now be delivered with maximum therapeutic benefits, minimizing toxicity and
sparing healthy tissues.
Radiation therapy uses high-energy ionizing radiation to kill cancer
cells. It is considered a local therapy because the cancer cells are destroyed
only in the anatomical area being treated. The radiation causes a breakage of
one or both stands of the DNA molecule inside the cells, therefor preventing
their ability to grow and divide. While cells in all phases of the cell cycle
can be damaged by radiation, the lethal effect of radiation may not be apparent
until after one or more cell divisions have occurred. Although normal cells can
also be affected by ionizing radiation, they are usually better able to repair
their DNA damage.
Radiation treatments can be administered externally or internally,
depending on the type and extent of the tumor, however only external radiation
can be administered in an out-patient basis. Some patients have both forms,
one after the other. X-rays, radioactive elements, and radioactive isotopes are
most often used in these forms of treatment.
External radiation treatments are administered by machines that deliver
high-energy radiation. These machines vary according to the amount and type of
energy produced. The kind of machine will differ depending on the type and
extent of the tumor. Technological advances have permitted the development of
machines with increased energy, allowing for precise treatments of deep seated
tumors with less damage to superficial tissues.
Treatment of cancer with radiation can be costly. It requires very
complex equipment and the service of many health care professionals. The exact
cost of the radiation therapy will depend of the type and number of treatments
given. Most health insurance policies cover charges for radiation therapy, and
in some states the Medicaid program may help pay for the treatments.
The side effects of radiation treatment vary from patient to patient.
Some may have no side effect or only a few mild ones through the course of
treatment. Some may have more serious side effects. The side effects one has
depends mostly on the treatment dose and the part of the body that is treated.
There are two main types of side effects: acute and chronic. Acute
occurs close to the time of the treatment and usually are gone completely within
a few weeks of finishing therapy. Chronic side effects may take months or years
to develop and are usually permanent. The most common side effects are fatigue,
skin changes, and loss of appetite. The can result from radiation to any
treatment site. Other side effects are related to treatment of specific areas,
such as hair loss as a result of radiation treatment to the head. The majority
of side effects will go away in time.

B.
Biological therapy (sometimes called immunotherapy, biotherapy, or
biological response modified therapy) is a promising new addition to the family
of cancer treatments. Biological therapies use the body's immune system, either
directly or indirectly, to fight cancer or to lessen side effects that may be
caused by some cancer treatments.
The body has a natural ability to protect itself against diseases,
including cancer. The immune system, a complex network of cells and organs that
work together to defend the body against attacks by foreign invaders, is one of
the body's main defenses against disease.
Researchers have found that the immune system may recognize the
difference between healthy cells and cancer cells in the body and eliminate
those that become cancerous. Cancer may develop when the immune system breaks
down or is overwhelmed. Biological therapies are designed to repair, stimulate
or enhance the immune system's natural anticancer function.
Immune system cells and proteins called antibodies, which are part of
the immune system, work against cancer and other diseases by creating an immune
response against foreign invaders. This immune response is unique because
antibodies are specifically programmed to recognize and defend against certain
antigens. Antibodies respond to antigens by latching on to them. Biological
therapies used to treat cancer target some of the defenses by boosting,
directing or restoring the body's own cancer-fighting mechanisms.

C.
Chemotherapy is the use of medications or chemicals with cancer-fighting
abilities. Chemotherapy drugs interfere with the cancer cells' ability to grow
or multiply. Different groups of drugs act on cells in different ways.
Identification of the type of disease is important because certain
chemotherapies work best for certain diseases. Even patients diagnosed with the
same disease may be treated with different agents, depending on what is known to
be most effective for the particular circumstances. Chemotherapy can damage
normal cells as well as cancer cells. Those normal cells most effected are ones
which divide rapidly. These include the hair follicles, cells in the
gastrointestinal tract and bone marrow.
Chemotherapy can be given in different ways. The five most common
methods are: intravenous, oral, intramuscular, intrathecal and intraperitoneal.
The intravenous route, or IV, is a very common way of giving medication
directly into a vein. A small plastic needle is inserted into one of the veins
in the lower arm. There is some discomfort during insertion because a needle
stick is required to get into the vein. After that, the administration of the
medication is usually painless. Chemotherapy flows from the IV bag through the
needle and catheter into the bloodstream. Sometimes a syringe is used to push
the chemotherapy through the tubing.
The oral method takes the form of either a pill, capsule or liquid taken
by mouth. This is the easiest and most convenient method and can usually be
done at home.
Intramuscular is when the chemotherapy is given by way of an injection
into the muscle. There is a slight sing as the needle is placed into the muscle
of the arm, thigh or buttocks. Although this procedure lasts only a few seconds,
the effect of the intramuscular chemotherapy may last much longer. This is
because the chemotherapy may be absorbed slowly through the muscular tissues and
into the bloodstream.
Certain forms of cancer have a tendency to spread to the nervous system.
To treat cancer that spreads to the spinal cord or brain, doctors may perform a
spinal tap and inject chemotherapy into the spinal fluid. The is known as the
intrathecal method of administration of chemotherapy.
Chemotherapy may also be given by an intraperitoneal port. This device
sits under the skin and requires no specific home care. The port allows for
placing chemotherapy directly into the abdominal cavity. This technique is used
to increase the concentration of the chemotherapy that contacts tumors in the
abdomen.
For some patients, IV insertions can eventually damage the veins in the
arm. Some patients have small veins and some have very few accessible veins.
Frequent IV insertions and too small or too few veins may prompt the doctor to
recommend a permanent type of IV catheter. Permanent catheters allow patients
to go home and receive chemotherapy without needing other IV's placed. Along
with receiving chemotherapy and IV fluids through this catheter, patients can
receive blood products and even have their blood drawn without painful needle
sticks.
Chemotherapy may be given once a day, once a week, or even once a month,
depending on the type of cancer and what research has shown is the best time
period for treatment. How much chemotherapy costs will depend on a lot of
things, such as the kind of drugs used and how often you take them. Some
medical insurance pays for chemotherapy and government programs such as Medicare
and Medicaid can also help cover the costs.
Side effects of chemotherapy vary from each patient. Some patients take
chemotherapy and feel no changes at all. However, chemotherapy sometimes makes
you feel sick after the drugs get into the body. This is because very strong
drugs are being used. They go after any cell that is quickly dividing, whether
it is a cancer cell or not. Cells in the hair, bone marrow, skin, mouth, and in
the stomach normally divide quickly in the body. This is why the side effects
of chemotherapy can mean hair loss or feeling tired. Sores in the mouth, dry
skin and hair, or sickness to the stomach are also common side effects of
chemotherapy.
There are some medications that a person can take that could help get
rid of some of the side effects. There are few lasting problems, and unpleasant
symptoms often go away as soon as the treatment is finished.
Chemotherapy might be taken before or after surgery. Or, it could be
administered with radiation treatment. Some people also have chemotherapy
without surgery or radiation. Chemotherapy is not new. It has been helping
people since the early 1950s. Today it can be very effective in killing cancer
cells.
V.
Cancer is a very serious disease, and is one which many people fear.
Ambulatory treatment for cancer can be done in several different ways, but the
most effective kinds of ambulatory care for cancer is prevention and early
detection. This way, it is possible that a person will not have to undergo
cancer treatments. However, if cancer is diagnosed in a person, ambulatory
treatment options are available in attempts to rid the body of the cancer. With
this in mind, today's cancer patients and those with a high-risk potential for
acquiring cancer, will have many options available to them to manage the disease.