Nonmelanoma
skin cancer
Skin
cancer is a disease state where malignant skin cells begin
to grow in the topmost layer of the skin (the epidermis) and
give rise to tumors that can cause significant morbidity and
in some cases, mortality. The United States is currently experiencing
a skin cancer epidemic, with continued increases in skin cancer
incidence rates over the last multiple decades, and a significant
mortality rate due mostly to melanoma.
Skin
cancer is generally divided into melanoma and nonmelanoma
types. Melanoma arises from pigment-creating cells called
melanocytes and can become locally and distantly aggressive
with mortality corresponding to the stage that it is detected.
Nonmelanoma skin cancer is comprised of basal cell carcinoma
(BCC) and squamous cell carcinoma (SCC) and to a very minor
extent, other rare malignancies. They are vastly more common
than melanoma, however many people are unfamiliar with these
skin cancers.
BCC
The
most common malignancy in humans, BCC develops in greater
than one million people every year in the United States. Approximately
80% of all skin cancers are BCC, a cancer that develops in
the basal cells (lowest layer in the epidermis). BCC may have
several appearances at the time it is detected: 1) a shiny
translucent or pearly nodule, 2) a sore that continuously
heals and then re-opens, 3) a pink slightly elevated growth,
4) reddish irritated patches of skin, or 5) a scar-like growth.
Most basal cell cancers appear on skin with a history of exposure
to the sun, such as the face, scalp, ears and upper trunk.
These cancers tend to be very slow-growing and spread internally
only very rarely, but dermatologists encourage early detection
to minimize disruption and risk to the surrounding skin.
SCC
About
16% of diagnosed skin cancers are SCC, with about 200,000
new cases per year. This cancer begins in the squamous cells,
which are found in the upper layer of the epidermis. SCC tends
to develop in light-skinned, middle-aged and elderly people
who have had significant, long-term sun exposure. SCC often
appears as: 1) a crusted or scaly, inflamed nodule, 2) a non-healing
ulcer, or 3) a crusted-over patch of skin. While most commonly
found on sun-exposed areas of the body, it can develop anywhere,
including the inside of the mouth and the genitals. SCC may
arise from precancerous, flaky or scaly, pink patches called
actinic keratoses. Early treatment is advised, as aggressive
or neglected SCC may metastasize (spread internally).
Causes
and Affected Persons
There
is significant evidence that ultraviolet light (UV) causes
skin cancer. UV light damages DNA of our skin cells, which
may lead to mutations and ultimately, malignant change in
affected cells. Humans with less pigment (melanin) such as
blonds, redheads and fair-skinned people cannot retard these
damaging rays from exerting their dangerous effects. Extensive
or repeated exposure to UV from the sun or a tanning bed significantly
raises one's risks for developing skin cancer. Additionally,
a strong family history of skin cancer or a weakened immune
system (immunocompromised) may lead to increased risk for
BCC or SCC.
The
Statistics
It
is estimated that one in five Americans will develop a skin
cancer in his/her lifetime. Well over one million skin cancers
are predicted to occur in Americans in 2008. Thousands of
people die from skin cancer every year, however, most will
due to melanoma. The costs of treating nonmelanoma skin cancer
exceed $1 billion annually in the U.S.
Treatment
The
treatment of nonmelanoma skin cancer varies with the tumor
type, size, location, patient health and age. Dermatologists/dermasurgeons
use techniques as varied as local chemotherapy creams, curettage
(scraping), excision, cryosurgery (freezing), laser surgery
or Mohs surgery (a specialized surgical removal with frozen
pathology) to treat skin cancers.
Prevention
The
two most effective ways to prevent skin cancer from occurring
or causing significant morbidity are: 1) limiting UV exposure
to the skin and 2) checking the skin regularly for changes
or suspicious areas. Regular use of broad-spectrum (UVA and
UVB light blocking) sunscreens with SPF at least 30 or higher,
avoidance of midday sun (10 am to 4pm), avoidance of tanning
bed use, and wearing clothing designed to block UV are all
effective ways to limit UV. Surveying your own skin, or having
a loved one survey your skin may be helpful to detecting suspicious
areas. Reporting skin changes to a physician and most specifically,
a dermatologist is always advised. Having a regular dermatologist
skin evaluation is a helpful tool to detect and treat skin
cancer.
Free
skin cancer screenings occur in our area several times through
the year. Patients with concerns over suspicious areas or
wanting to establish regular dermatologist-performed skin
exams are encouraged to make an appointment.
