ACTINIC KERATOSIS
WHAT
IS ACTINIC KERATOSIS
You have surely seen an actinic keratosis. The name may be unfamiliar,
but the appearance is commonplace. Anyone who spends time in the
sun runs a high risk of developing one or more. An actinic keratosis,
also known as a solar keratosis, is a scaly or crusty bump that
arises on the skin surface. The base may be light or dark, tan,
pink, red, or a combination of these ... or the same color as your
skin. The scale or crust is dry and rough. Occasionally it itches
or produces a pricking or tender sensation. The skin lesion develops
slowly and usually reaches a size from an eighth to a quarter of
an inch. A keratosis is most likely to appear on the face, ears,
bald scalp, neck, backs of hands and forearms, and lips. It tends
to lie flat against the skin of the head and neck and be elevated
on arms and hands.
WHY
IS IT DANGEROUS?
Actinic Keratosis can be the first step in
the development of skin cancer. Therefore it is referred to as a
precursor of cancer or a precancer. It is estimated that up to 10
percent of active lesions, which are redder and more tender than
the rest, will take the next step and progress to squamous cell
carcinomas. They are usually not life threatening, provided they
are detected and treated in the early stages. However, left untreated,
they can grow large and invade the surrounding tissue. On rare occasions,
they metastasize or spread to the internal organs.
The most aggressive form of keratosis, actinic cheilitis, appears
on the lips and can evolve into squamous cell carcinoma. When this
happens, roughly one-fifth of these carcinomas metastasize. The
presence of actinic keratoses indicates that sun damage has occurred
and that any kind of skin cancernot just squamous cell carcinoma
can develop.
WHAT DOES ACTINIC KERATOSIS LOOK
LIKE?
- Back
of handscattered, thickened red, scaly patches.
- Sun-damaged
forehead or bald scalpsmall red bumps and/or small tan
crusts.
- Lower
lipfissures filled with dried blood and large keratosis
covered with thorny scale.
- Cheek
and ear-crusted lesionsranging in color from red to
brown.
If
you spot any of these, consult your doctor promptly.
WHAT IS THE CAUSE?
Sun exposure is the cause of almost all actinic keratoses. Sun damage
to the skin accumulates over time, so that even a brief exposure
adds to the lifetime total. The likelihood of developing keratoses
is highest in regions close to the equator. However, regardless
of climate, everyone is exposed to the sun. Ultraviolet rays reflect
off sand, snow, and other surfaces; about 80 percent can pass through
clouds.
WHO IS AT GREATEST RISK?
People who have fair skin, blonde or red hair, blue, green, or gray
eyes are at the greatest risk. Because their skin has less protective
pigment, they are the most susceptible to sunburn. Even those who
are darker-skinned can develop keratoses if they expose themselves
to the sun without protection. African-Americans, however, rarely
have these lesions.
Individuals, who are immunosuppressed as a result of cancer chemotherapy,
AIDS, or organ transplantation, are also at higher risk.
HOW COMMON IS IT?
One in six people will develop an actinic keratosis in the course
of a lifetime, according to the best estimates. Older people are
more likely than younger ones to have actinic keratoses, because
cumulative sun exposure increases with the years. A survey of older
Americans found keratoses in more than half of the men and more
than a third of the women aged 65 to 74 who had a high degree of
lifetime sun exposure. Some experts believe the majority of people
who live to the age of 80 have keratoses. Because more than half
of an average person's lifetime sun exposure occurs before the age
of 20, keratoses appear even in people in their early twenties who
have spent too much time in the sun with little or no protection.
HOW IS IT TREATED?
There are a number of effective treatments for actinic keratoses.
Not all keratoses need to be removed. The decision on whether and
how to treat is based on the nature of the lesion, your age, and
your health.
Curettage and Electrodessicationis the most commonly
used treatment. The physician scrapes the lesion and takes a biopsy
to test for malignancy. Bleeding is controlled by electrocautery-heat
produced by an electric needle.
Shave Removalutilizes a scalpel to shave the keratosis
and obtain a specimen for testing. The base of the lesion is destroyed,
and the bleeding is stopped by cauterization.
Cryosurgeryfreezes off the lesions through application
of liquid nitrogen with a special spray device or cotton-tipped
applicator. It does not require anesthesia and produces no bleeding,
but white spots sometimes result.
Dermabrasionremoves the upper layers of the skin by
sanding or using a fine wire brush operating at 20-25,000 revolutions
per minute. Redness and soreness usually disappear after a few days.
Topical Medicationstwo medicated creams are effective
in removing keratoses, particularly when lesions are numerous. The
medication is applied twice daily, with progress checked by a physician.
5-Fluorouracil (5-FU) cream is used for three to five weeks. Treatment
leaves the affected area temporarily reddened and may cause some
discomfort resulting from skin breakdown. Masoprocol cream, 10%,
the newest topical treatment, is applied for 28 days. Redness and
flaking are the most common side effects; most reactions are usually
reported as mild to moderate.
HOW TO PREVENT IT
The best way to prevent actinic keratosis is to protect yourself
from the sun.
- Limit
the amount of time spent in the sun.
- Avoid
the peak hours from 10 a. m. to 4 p.m.
- Cover
up with protective clothing, including a broad-brimmed hat.
- Wear
a broad-spectrum sunscreen with a sun protection factor (SPF)
of 15 or greater.
- Avoid
tanning parlors and artificial tanning devices.
- Keep
newborns out of the sun. Sunscreens can be used on babies over
the age of six months.
- Teach
your children good sun-protection practices.
- Perform
regular skin self-examination and consult a dermatologist if you
find a suspicious area.
Actinic
keratosis is skin cancer's warning signal. Heed that signal.