Basal cell carcinoma is
the most common form of nonmelanoma skin cancer. It's also the most
easily treated and the least likely to spread.
But though basal cell carcinomas are rarely fatal, they can cause
extensive damage to surrounding tissue and bone if they're not removed.
Basal cell carcinomas also have a high recurrence rate; if you've had
one basal cell carcinoma, you have a good chance of developing another
within five years.
Most basal cell carcinomas are caused by long-term exposure to
ultraviolet (UV) radiation from sunlight. Avoiding the sun as much as
possible is the best protection. Sunscreen is an important part of a
sun-safety program, but by itself can't prevent basal cell carcinoma or
other forms of skin cancer.
Basal cell carcinomas usually develop on sun-exposed parts of your body,
especially your head and neck. A much smaller number occur on the trunk
and legs. Yet basal cell carcinomas can also occur on parts of your
body that rarely see the light of day.
Although a general warning sign of skin cancer is a sore that won't heal
or that repeatedly bleeds and scabs over, basal cell tumors are likely
to take one of these forms:
* A pearly white or waxy bump, often with visible blood vessels on
your face, ears or neck. The bump may bleed, develop a crust or form a
depression in the center. In darker skinned people, this type of tumor
is usually brown or black.
* A flat, scaly, brown or flesh-colored patch on your back or chest.
Over time, these patches can grow quite large — up to about 4 to 6
inches (about 10 to 15 centimeters).
* More rarely, a white, waxy scar. This type of basal cell carcinoma
is easy to overlook, but it may be a sign of a particularly invasive
and disfiguring cancer called morpheaform basal cell carcinoma.
When to see a doctor
Some basal cell carcinomas may be difficult to distinguish from ordinary
sores. Yet the sooner they're diagnosed and treated, the better the
outcome. See your dermatologist if you have:
* A skin sore that bleeds easily or doesn't heal in about two weeks
* A sore that repeatedly crusts or oozes
* Visible blood vessels in or around a sore
* A scar in an area where you haven't injured yourself
Your skin consists of three layers — the epidermis, which is closest to
the surface, the dermis and the subcutis. Basal cells, which produce new
skin cells, are at the bottom or basal layer of the epidermis.
Normally, the new cells push older cells toward the skin's surface,
where the old cells die and are sloughed off. This process is controlled
by DNA, the body's genetic blueprint. But when DNA is damaged — by
solar radiation, for example — the process of cell death and renewal no
longer occurs as it should. Instead, cells may grow out of control and
eventually form a cancerous tumor.
As with many other diseases, basal cell carcinomas seem to result from a
combination of genetic and environmental factors. Most of the
environmental damage to skin cells comes from exposure to UV radiation
from sunlight. Although some studies show that the greatest harm occurs
during childhood and adolescence, UV damage also appears to be
cumulative, so the more time you spend in the sun, the greater your
chance of developing skin cancer. Your risk increases even more if most
of your outdoor exposure takes place in locales or at times of day when
the sun is strongest.
Other environmental factors that can lead to basal cell carcinoma include:
* Therapeutic radiation. Psoralen plus ultraviolet A (PUVA)
treatments for psoriasis and X-rays to the head or neck increase your
risk of basal cell carcinoma as well as of other, more serious forms of
skin cancer. It can take years for skin cancers to develop, and many
radiation-induced carcinomas that occur later in life may have had their
origins in radiation treatments for childhood acne or ringworm. The
likelihood that therapeutic radiation will cause cancer depends on a
number of factors, including the pigmentation in your skin, the total
dose of radiation you receive and your medical status.
* Chemical toxins. Arsenic, a toxic metal that's found widely in the
environment, is a well-known cause of basal cell carcinoma and other
cancers. Though arsenic contaminates the soil, air and groundwater, most
people get their greatest exposure in food, especially chicken, beef
and fish, and in wine grapes sprayed with arsenic-containing toxins. The
U.S. Department of Health and Human Services estimates that the average
American ingests 11 to 14 milligrams of arsenic every day. Farmers,
refinery workers, and people who drink contaminated well water or live
near smelting plants are likely to ingest much higher levels.
* Immunosupressant drugs. People who take medications to prevent
organ rejection after transplant surgery have a greatly increased risk
of basal cell carcinoma, though symptoms may not appear for years after
Several inherited disorders cause basal cell carcinoma or greatly increase your risk, including:
* Nevoid basal cell carcinoma syndrome (Gorlin's syndrome). People
with this rare genetic disorder have numerous basal cell carcinomas as
well as pitting on their hands and feet, spine abnormalities, and
* Bazex's syndrome. This disorder is marked by numerous basal cell
tumors on the face and by a lack of sweating and body hair.
* Xeroderma pigmentosum. People with xeroderma pigmentosum, which
causes an extreme sensitivity to sunlight, are at high risk of skin
cancer because they have little or no ability to repair damage to the
skin from ultraviolet light.
Factors that increase your risk of basal cell carcinoma include:
* Chronic sun exposure. A lifetime spent in the sun — or in
commercial tanning booths — is the most common cause of basal cell
carcinoma. The threat is greater if you live in a sunny or high-altitude
climate, both of which expose you to more UV radiation. The risk is
also higher if most of your exposure occurred before the age of 18.
* Fair skin. If you have very light skin or you freckle or sunburn
easily, you're more likely to develop skin cancer than is someone with a
darker complexion. Your risk is greater if you had at least one
blistering sunburn in childhood, though sunburns later in life don't
seem to increase the risk of basal cell carcinoma.
* Your sex. Men are far more likely to develop basal cell carcinoma
than women are, though the incidence in women is increasing.
* Your age. Because basal cell carcinomas often take decades to
develop, about 80 percent of basal cell carcinomas occur in people age
50 or older. In recent years, however, the tumors have become much more
common in younger people and are increasing every year among adults of
* A personal or family history of skin cancer. If you've had basal
cell carcinoma one or more times, you have a good chance of developing
it again. You're also at greater risk if a close relative has had skin
* Immune-suppressing drugs. Taking medications that suppress your
immune system, especially after transplant surgery, significantly
increases your risk of skin cancer. Tumors in people with a weakened
immune system generally are more aggressive than they are in otherwise
Basal cell carcinomas that are diagnosed and treated early usually cause
no problems. But untreated cancers, especially aggressive morpheaform
tumors, can invade and destroy nearby muscles, nerves and bone. One
unusual type of basal cell carcinoma — basosquamous — is capable of
spreading to other parts of your body.
Basal cell carcinomas are also difficult to eliminate completely. Even
after successful treatment, they may recur, often in the same place.
Having more than one tumor initially or a tumor on the trunk of your
body makes recurrence more likely.
A history of basal cell carcinoma may also increase the chance of
developing more serious types of skin cancer, such as squamous cell
carcinoma and even malignant melanoma — probably because of long-term
sun exposure. Researchers are debating whether having basal cell
carcinoma leads to an increased risk of other kinds of cancer.
Preparing for your appointment
If you have a skin wound or lesion that concerns you, call your doctor.
He or she may recommend that you schedule an appointment with a doctor
who specializes in the diagnosis and treatment of skin conditions
(dermatologist). In order to ensure a timely examination, be sure to
mention when you make your appointment that your doctor has suggested
you be evaluated for possible skin cancer.
If you've already had skin cancer, you're at significantly increased
risk of a second cancer. Talk with your dermatologist about how often
you should be screened for a recurrence. If you have a new wound or
lesion that you suspect may be cancerous, schedule an appointment with
your dermatologist as soon as possible.
Here's some information to help you get ready for your appointment, and what to expect from your doctor.
What you can do
* Write down your medical history, including other conditions for
which you've been treated. Be sure to include any radiation therapy you
may have received, even years ago.
* Note any personal history that exposed you to excessive UV light,
including sunlight or tanning beds. For example, your doctor will be
interested to know if you have worked as an outdoor lifeguard or spent
lots of time at the beach.
* Make a list of immediate family members who have had skin cancer,
to the best of your ability. Skin cancer in a parent, grandparent, aunt,
uncle or sibling is important history to share with your doctor.
* Make a list of your medications and natural remedies. Include any
prescription or over-the-counter medications you're taking, as well as
all vitamins, supplements or herbal remedies.
* Write down questions to ask your doctor. Creating your list of
questions in advance can help you make the most of your time with your
* Find a family member or friend who can join you for your
appointment. Although skin cancer is usually highly treatable, just
hearing the word "cancer" can make it difficult for most people to focus
on what the doctor says next. Take someone along who can help soak up
all the information.
Below are some basic questions to ask your doctor about basal cell
carcinoma. If any additional questions occur to you during your visit,
don't hesitate to ask.
* Do I have skin cancer? What kind?
* How is this type of skin cancer different from other types?
* Has my cancer spread?
* What treatment approach do you recommend?
* What are the possible side effects of this treatment?
* Will I have a scar after treatment?
* Am I at risk of this condition recurring?
* Am I at risk of other types of skin cancer?
* How often will I need follow-up visits after I finish treatment?
* Are my family members at risk of skin cancer?
* Are there any brochures or other printed material that I can take home with me? What Web sites do you recommend visiting?
What to expect from your doctor
Your doctor is likely to ask you a number of questions. Being ready to
answer them may reserve time to go over any points you want to talk
about in-depth. Your doctor may ask:
* When did you first notice this skin growth or lesion?
* Has it grown significantly since you first found it?
* Is the growth or lesion painful?
* Do you have any other growths or lesions that concern you?
* Have you had a previous skin cancer?
* Has anyone in your family had skin cancer? What kind?
* How much exposure to the sun or tanning beds did you have as a child?
* How much exposure to the sun or tanning beds do you have now?
* Are you currently taking any medications?
* Are you currently or have you previously used herbal remedies?
* Have you ever received radiation therapy for another medical condition?
* Have you ever taken medications that suppress your immune system?
* What other significant medical conditions have you been treated for, including in your childhood?
* Do you or did you smoke? How much?
* Do you now or have you ever had a job that may have exposed you to pesticides or herbicides?
* Do you now or have you ever relied on well water as your primary water source?
* Do you take precautions to stay safe in the sun, such as avoiding midday sun and using sunscreen?
* Do you examine your own skin on a regular basis?
What you can do in the meantime
In the time leading up to your appointment, talk with family members to
find out whether any of your close relatives have been diagnosed or
treated for skin cancer, and what kind. This will help your doctor
diagnose your condition and plan the most effective treatment and
follow-up care plan for you.
Tests and diagnosis
In addition to taking a complete medical history and checking the
affected area of skin, your doctor may remove a small skin sample
(biopsy) for examination under a microscope. Often, the biopsy is sent
to a pathologist who has special expertise in diagnosing skin samples.
A suspected basal cell carcinoma is often biopsied by shaving off the
top layers of skin with a surgical blade. Tumors that have spread deeper
into the skin may be partially or completely removed (incisional or
excisional biopsy). Because all biopsies are likely to leave a small
scar, talk to your doctor about the types of biopsies and their
potential for scarring before having the procedure.
Treatments and drugs
A number of therapies exist for treating basal cell carcinoma; the most
appropriate one depends on the type, location and severity of the tumor.
Some commonly used basal cell carcinoma treatments include:
* Electrodesiccation and curettage (ED and C). This treatment can
successfully remove new basal cell carcinomas, but is less effective for
recurring tumors. It's often used for tumors located on your trunk,
arms or legs. During the procedure, your dermatologist removes the
surface of the skin cancer with a scraping instrument (curette) and then
sears the base of the tumor with an electric needle.
* Surgical excision. In this procedure, which is used for both new
and recurring tumors, your doctor cuts out the cancerous tissue and a
surrounding margin of healthy skin. In some cases, you may have a wide
excision, which involves removing additional normal skin around the
tumor. To minimize scarring, especially on your face, consult a doctor
skilled in skin reconstruction.
* Freezing. This involves removing cancerous cells by freezing them
with liquid nitrogen (cryosurgery). It's useful for tumors on certain
parts of your body and for people with more than one tumor, but it has
definite drawbacks, including crusting, slow healing and scarring.
* Mohs' surgery. This is an effective treatment for recurring basal
cell carcinomas and those that are large, deep, fast-growing,
morpheaform or on your face. During the procedure, your doctor removes
the tumor layer by layer, examining each layer under the microscope
until no abnormal cells remain. This allows the entire growth to be
removed without taking an excessive amount of surrounding healthy
tissue. Because it requires particular expertise, Mohs' surgery should
only be performed by doctors specifically trained in the procedure.
* Laser surgery. In this relatively new therapy, a laser is used to
vaporize superficial basal cell carcinomas. To minimize bleeding, lasers
are sometimes used instead of scalpels during surgical excisions.
* Topical treatments. Some superficial basal cell carcinomas are
treated with creams or ointments. Tazarotene (Tazorac), a prescription
cream normally used for acne, appears to be effective in preventing
basal cell tumors. It may have a role in treatment as well, but it
hasn't yet been approved for this use, as tests are ongoing. Other,
approved topical treatments include imiquimod (Aldara) and
5-fluorouracil. These prescription medications require careful
supervision because both can cause severe skin irritation as well as
systemic side effects.
Most basal cell carcinomas can be prevented. To protect yourself:
* Avoid the midday sun. Sunlight is strongest between 10 a.m. and 4
p.m., so try to schedule outdoor activities for other times of the day,
even in winter or when it's cloudy. You absorb UV radiation year-round,
and clouds offer little protection from damaging rays. Keep in mind that
sunlight is more intense when it reflects off water, sand and snow.
* Use sunscreen year-round. Sunscreens don't filter out all harmful
UV radiation, but they play a major role in an overall sun protection
program. Wear a broad-spectrum sunscreen with a sun protection factor
(SPF) of at least 15 when you go outside, year-round. Use about 1 ounce
(29.5 milliliters) — the amount that fits in your palm — to cover your
entire body, including your lips, ears and the backs of your hands and
neck. Apply sunscreen 20 to 30 minutes before sun exposure and reapply
it every two hours throughout the day, as well as after swimming or
A sunscreen called Anthelios SX, which has been widely used in Europe,
is now available in the United States. It offers better protection from
UVA rays than do traditional broad-spectrum sunscreens and may be more
effective in preventing skin cancer. Still, don't rely on any sunscreen
as your sole means of sun protection.
* Wear protective clothing. Because no sunscreen provides complete
protection, it's important to also wear tightly woven clothing that
covers your arms and legs and a broad-brimmed hat rather than a baseball
cap or visor. Some companies sell photoprotective clothing. Your
dermatologist can recommend an appropriate brand, or you can research
this clothing online. And don't forget sunglasses. Look for a pair that
provides full protection from both UVA and UVB rays.
* Be aware of sun-sensitizing medications. Some common prescription
and over-the-counter drugs make your skin more sensitive to sunlight.
These include antibiotics, certain cholesterol, high blood pressure and
diabetes medications, ibuprofen (Advil, Motrin, others), and the acne
medication isotretinoin (Accutane). Ask your pharmacist about the side
effects of any medications you take. If they make you more sun
sensitive, take extra precautions.
* Perform regular skin checks. Examine your skin often for new
growths or changes in existing moles, freckles, bumps and birthmarks.
Don't forget to check your scalp, ears, and even your buttocks. If you
have had one or more basal cell carcinomas in the past, you and your
doctor should be especially vigilant about checking for recurring
* Get enough vitamin D. This vitamin may help lower the risk of
certain cancers. Although it's normally produced by sunlight on your
skin, many experts recommend getting your daily requirement of vitamin D
through food or supplements.
* Get your five a day. Studies suggest that a diet rich in fruits
and vegetables may lower your risk of cancer, likely due to antioxidant
nutrients such as vitamin C, vitamin E and carotenoids. The U.S. Dietary
Guidelines recommend that adults following an average diet — about
2,000 calories daily — eat 4.5 cups (nine servings) of fruits and
vegetables each day.