All about cancer

Causes
Cells are the building blocks of living
things. Cancer grows out of normal cells
in the body. Normal cells multiply when
the body needs them, and die when the
body doesn't need them. Cancer
appears to occur when the growth of
cells in the body is out of control and
cells divide too quickly. It can also occur
when cells"forget" how to die.
There are many different kinds of
cancers. Cancer can develop in almost
any organ or tissue, such as the lung,
colon, breast, skin, bones, or nerve
tissue.
There are many causes of cancers,
including:
Benzene and other chemicals
Certain poisonous mushrooms and a
type of poison that can grow on peanut
plants (aflatoxins)
Certain viruses
Radiation
Sunlight
Tobacco
However, the cause of many cancers
remains unknown.
The most common cause of cancer-
related death is lung cancer.
The three most common cancers in men
in the United States are:
Prostate cancer
Lung cancer
Colon cancer
In women in the U.S., the three most
common cancers are:
Breast cancer
Colon cancer
Lung cancer
Some cancers are more common in
certain parts of the world. For example,
in Japan, there are many cases of
gastric cancer, but in the U.S. this type of
cancer is pretty rare. Differences in diet
may play a role.
Some other types of cancers include:
Brain cancer
Cervical cancer
Hodgkin's lymphoma
Kidney cancer
Leukemia
Liver cancer
Non-Hodgkin's lymphoma
Ovarian cancer
Skin cancer
Testicular cancer
Thyroid cancer
Uterine cancer
Symptoms
Symptoms of cancer depend on the type
and location of the tumor. For example,
lung cancer can causecoughing,
shortness of breath, or chest pain. Colon
cancer often causes diarrhea,
constipation, and blood in the stool.
Some cancers may not have any
symptoms at all. In certain cancers, such
as gallbladder cancer, symptoms often
do not start until the disease has
reached an advanced stage.
The following symptoms can occur with
most cancers:
Chills
Fatigue
Fever
Loss of appetite
Malaise
Night sweats
Weight loss
Exams and Tests
Like symptoms, the signs of cancer vary
based on the type and location of the
tumor. Common tests include the
following:
Biopsy of the tumor
Blood chemistries
Bone marrow biopsy (for lymphoma or
leukemia)
Chest x-ray
Complete blood count (CBC)
CT scan
Most cancers are diagnosed by biopsy.
Depending on the location of the tumor,
the biopsy may be a simple procedure or
a serious operation. Most patients with
cancer have CT scans to determine the
exact location and size of the tumor or
tumors.
A cancer diagnosis is difficult to cope
with. It is important, however, that you
discuss the type, size, and location of
the cancer with your doctor when you are
diagnosed. You also will want to ask
about treatment options, along with their
benefits and risks.
It's a good idea to have someone with
you at the doctor's office to help you get
through the diagnosis. If you have
trouble asking questions after hearing
about your diagnosis, the person you
bring with you can ask them for you.
Treatment
Treatment also varies based on the type
of cancer and its stage. The stage of a
cancer refers to how much it has grown
and whether the tumor has spread from
its original location.
If the cancer is confined to one location
and has not spread, the most common
goals for treatment are surgery and cure.
This is often the case withskin cancers,
as well as cancers of the lung, breast,
and colon.
If the tumor has spread to local lymph
nodes only, sometimes these can also
be removed.
If surgery cannot remove all of the
cancer, the options for treatment include
radiation, chemotherapy, or both. Some
cancers require a combination of
surgery, radiation, and chemotherapy.
Although treatment for cancer can be
difficult, there are many ways to keep up
your strength.
If you have radiation treatment, know
that:
Radiation treatment is painless.
Treatment is usually scheduled every
weekday.
You should allow 30 minutes for each
treatment session, although the
treatment itself usually takes only a few
minutes.
You should get plenty of rest and eat a
well-balanced diet during the course of
your radiation therapy.
Skin in the treated area may become
sensitive and easily irritated.
Side effects of radiation treatment are
usually temporary. They vary depending
on the area of the body that is being
treated.
If you are going through chemotherapy,
you should eat right. Chemotherapy
causes your immune system to weaken,
so you should avoid people with colds or
the flu. You should also get plenty of
rest, and don't feel as though you have
to accomplish tasks all at once.
It will help you to talk with family, friends,
or a support group about your feelings.
Work with your health care providers
throughout your treatment. Helping
yourself can make you feel more in
control.
Support Groups
A cancer diagnosis often causes a lot of
anxiety and can affect your entire quality
of life. Several support groups for cancer
patients can help you cope.
Outlook (Prognosis)
The outlook depends on the type of
cancer. Even among people with one
type of cancer, the outcome varies
depending on the stage of the tumor
when they are diagnosed.
Some cancers can be cured. Some
cancers that are not curable can still be
treated well. And some patients can live
for many years with their cancer. Other
tumors are quickly life-threatening.
Possible Complications
One complication is that the cancer may
spread. Other complications vary with
the type and stage of the tumor.
When to Contact a Medical Professional
Contact your health care provider if you
develop symptoms of cancer.
Prevention
One of the best ways to prevent cancer
is to not smoke or chew tobacco. Many
cancers can be prevented by avoiding
risk factors such as excessive exposure
to sunlight and heavy drinking.
Cancer screenings, such as
mammography and breast examination
for breast cancer and colonoscopy for
colon cancer, may help catch these
cancers at their early stages when they
are most treatable. Some people at high
risk for developing certain cancers can
take medication to reduce their risk.