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SKIN
CANCER
Skin
cancer is the most prevalent of all cancers. It is estimated
that more than one million Americans develop skin cancer every
year. Everyone should develop a regular routine inspection
of their body for any skin changes such as a growth, mole,
sore or sudden skin discoloration. A dermatologist should be
consulted should any of these occur. The following descriptions
may be helpful in assisting with the recognition of skin cancers.
Precancerous
Skin Conditions
Actinic keratoses are small scaly spots most commonly found on the face, lower
arms, and back of hands in fair-skinned individuals who have had significant
sun exposure. If not treated, some actinic keratoses may become skin cancers
requiring more extensive treatment. If diagnosed in the early stages, actinic
keratoses can be removed by cryotherapy (freezing with liquid nitrogen) or
other dermatologic procedures. Sunscreens help prevent actinic keratoses.
Basal
Cell Carcinoma
Basal cell carcinoma is a skin cancer usually appearing as a raised translucent
patch or nodule. These skin cancers are usually found on the head, neck, and
hands, and occasionally can appear on the trunk as red areas. Basal cell carcinomas
seldom occur in African-Americans, but they are the most common skin cancers
found in fair-skinned persons. People who have this cancer often have light-colored
eyes, hair and complexions, and do not tan easily. These tumors do not spread
quickly and can take many months or years to grow to a diameter of one-half
inch. Untreated, the cancer will begin to bleed, crust over, heal, and then
the cycle repeats. Although this cancer rarely spreads to other parts of the
body (metastasizes), it can extend below the skin to the bone and cause considerable
local damage.
Squamous
Cell Carcinomas
This skin cancer is the second most common in fair-skinned persons and appears
as a bump, or a red, scaly patch. It is typically found on the rim of the ear,
the face, lips and mouth and is rarely found in dark-skinned persons. This
cancer can develop into large masses and can metastasize. When found early,
the cure rate for both basal and squamous cell carcinomas is good. Mohs micrographic
surgery has cure rates approaching 99% for primary lesions.
Melanoma
More than 40,000 new cases of malignant melanomas occur yearly in our country
causing in excess of 7,000 deaths. It is important to note that the death
rate is declining because patients are seeking help earlier. Like the less
aggressive skin cancers, basal cell and squamous cell carcinomas, melanoma
is almost always curable when detected in its early stages. Excessive sun
exposure, particularly sunburn, is the most important preventable cause
of melanoma, especially among light-skinned individuals. Heredity also
plays a part since a person has an increased chance of developing melanoma
if a family member has had a melanoma. Atypical moles (dysplatic nevi),
which may run in families, and a high number of moles, can serve as markers
for people at higher risk for developing melanoma.
Melanoma
has its beginnings in melanocytes, the skin cells that produce
the dark, protective pigment called melanin. It is melanin
that makes the skin tan, acting as partial protection against
the sun. Melanoma cells usually continue to produce melanin,
which accounts for the cancers appearing in mixed shades of
tan, brown, and black. Melanoma can also be red or white. Melanoma
can spread to other parts of the body through the bloodstream
and the lymph drainage system, making treatment essential.
About
40-50% of the malignant melanomas develop from pigmented moles;
almost all the rest arise from melanocytes in normal skin.
The very rare malignant melanomas of childhood almost always
arise from large pigmented moles (giant congenital nevi) present
at birth. Halo nevi usually resolve spontaneously but very
rarely are melanomas. Although melanomas are more common during
pregnancy, pregnancy does not increase the likelihood that
a mole will become a melanoma. Nevi frequently change in size
or shape during pregnancy.
Melanoma
may suddenly appear without warning, but it may also begin
in, or near a mole or another dark spot in the skin. It is
important to know the location and appearance of the moles
on our bodies so any change will be noticed.
Warning
signs of melanoma include: changes in the surface of a mole;
scaliness, oozing, bleeding, or in the appearance of a new
bump; spread of pigment from the border into a surrounding
skin; and change in sensation including itchiness, tenderness
or pain. Dark-skinned people can develop melanoma especially
on the palms of the hands, soles of the feet, under nails,
or in the mouth. The most important step you can take is to
have any changing mole examined by a dermatologist so that
any early melanoma can be removed while still in the curable
stage. The warning signs of melanoma can be easily remembered
by the pneumonic "ABC" as shown below:
ABCDE's
of Melanoma:
- Asymmetry
- Border
irregularity
- Color
variability
- Diameter
- Evolving
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