Source: Cancer Resource Room
What are
Basal Cell and Squamous Cell Carcinomas?
The two most common kinds of skin cancer
are basal cell carcinoma and squamous
cell carcinoma. (Carcinoma is cancer that
begins in the cells that cover or line
an organ.) Basal
cell carcinoma accounts for more than
90 percent of all skin cancers in the
United States. It is a slow-growing cancer
that seldom spreads to other parts of
the body. Squamous cell carcinoma also
rarely spreads, but it does so more often
than basal cell carcinoma. However, it
is important that skin cancers be found
and treated early because they can invade
and destroy nearby tissue.
Basal cell carcinoma and squamous cell
carcinoma are sometimes called nonmelanoma
skin cancer. Another type of cancer that
occurs in the skin is melanoma, which
begins in the melanocytes.
Cause and Prevention of Skin
Cancer
Skin cancer is the most common
type of cancer in the United States. According
to current estimates, 40 to 50 percent
of Americans who live to age 65 will have
skin cancer at least once. Although anyone
can get skin cancer, the risk is greatest
for people who have fair skin that freckles
easily -- often those with red or blond
hair and blue or light-colored eyes.
Ultraviolet (UV) radiation from the sun
is the main cause of skin cancer. (Two
types of ultraviolet radiation -- UVA
and UVB -- are explained in the ultraviolet
(UV) radiation definition in the Dictionary.)
Artificial sources of UV radiation, such
as sunlamps and tanning booths, can also
cause skin cancer.
The risk of developing skin cancer is affected
by where a person lives. People who live
in areas that get high levels of UV radiation
from the sun are more likely to get skin
cancer. In the United States, for example,
skin cancer is more common in Texas than
it is in Minnesota, where the sun is not
as strong. Worldwide, the highest rates
of skin cancer are found in South Africa
and Australia, areas that receive high
amounts of UV radiation.
In addition, skin cancer is related to
lifetime exposure to UV radiation. Most
skin cancers appear after age 50, but
the sun's damaging effects begin at an
early age. Therefore, protection should
start in childhood to prevent skin cancer
later in life.
Whenever possible, people should avoid
exposure to the midday sun (from 10 a.m.
to 2 p.m. standard time, or from 11 a.m.
to 3 p.m. daylight saving time). Keep
in mind that protective clothing, such
as sun hats and long sleeves, can block
out the sun's harmful rays. Also, lotions
that contain sunscreens can protect the
skin. Sunscreens are rated in strength
according to a sun protection factor (SPF),
which ranges from 2 to 30 or higher. Those
rated 15 to 30 block most of the sun's
harmful rays.
NCI is supporting research to try to find
new ways to prevent skin cancer. This
research involves people who have a high
risk of developing skin cancer -- those
who have already had the disease and those
who have certain other rare skin diseases
that increase their risk of skin cancer.
What
are the symptoms of skin cancer?
The most common warning sign
of skin cancer is a change on the skin,
especially a new growth or a sore that
doesn't heal. Skin cancers don't all look
the same. For example, the cancer may
start as a small, smooth, shiny, pale,
or waxy lump. Or it can appear as a firm
red lump. Sometimes, the lump bleeds or
develops a crust. Skin cancer can also
start as a flat, red spot that is rough,
dry, or scaly.
To see an example of Basal
Cell Carcinoma of the Face >>>
Both basal and squamous cell cancers are
found mainly on areas of the skin that
are exposed to the sun -- the head, face,
neck, hands, and arms. However, skin cancer
can occur anywhere.
Actinic keratosis, which appears as rough,
red or brown scaly patches on the skin,
is known as a precancerous condition because
it sometimes develops into squamous cell
cancer. Like skin cancer, it usually appears
on sun-exposed areas but can be found
elsewhere.
Changes in the skin are not sure signs
of cancer; however, it is important to
see a doctor if any symptom lasts longer
than 2 weeks. Don't wait for the area
to hurt -- skin cancers seldom cause pain.
Detection of Skin Cancer
The cure rate for skin cancer could be
100 percent if all skin cancers were brought
to a doctor's attention before they had
a chance to spread. Therefore, people
should check themselves regularly for
new growths or other changes in the skin.
Any new, colored growths or any changes
in growths that are already present should
be reported to the doctor without delay.
Doctors should also look at the skin during
routine physical exams. People who have
already had skin cancer should be sure
to have regular exams so that the doctor
can check the skin -- both the treated
areas and other places where cancer may
develop.
How are
basal cell carcinoma dn squamous
cell carcinoma diagnosed?
Basal cell carcinoma and squamous
cell carcinoma are generally diagnosed
and treated in the same way. When an area
of skin does not look normal, the doctor
may remove all or part of the growth.
This is called a biopsy. To check for
cancer cells, the tissue is examined under
a microscope by a pathologist or a dermatologist.
A biopsy is the only sure way to tell
if the problem is cancer.
Doctors generally divide skin cancer into
two stages: local (affecting only the
skin) or metastatic (spreading beyond
the skin). Because skin cancer rarely
spreads, a biopsy often is the only test
needed to determine the stage. In cases
where the growth is very large or has
been present for a long time, the doctor
will carefully check the lymph nodes in
the area. In addition, the patient may
need to have additional tests, such as
special x-rays, to find out whether the
cancer has spread to other parts of the
body. Knowing the stage of a skin cancer
helps the doctor plan the best treatment.
To read more about Skin
Cancers >>>
Support
& Education Programs
We know that being diagnosed with cancer can be stressful for you and your
family. We offer a variety of cancer support services to help patients and
families gain the support and information they will need to meet the challenges
ahead.
To find free education and support workshops
plus wellness services offered this
month, please view the HOPES
calendar.
Read the most recent SUPPORT
publication, a resource written by
patients and families for patients and families >>>
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