a disease in which malignant (cancer) cells form in
Skin cancer is the most common cancer, and is increasing rapidly. Although
more benign forms of skin cancer such as basal cell
and squamous cell carcinomas are on the rise, the
greatest increase has been in melanoma, the most
serious and most deadly type of skin cancer. In
fact, the percentage of people with melanoma has
more than doubled in the last 30 years.
Melanoma develops in the cells that produce
melanin (melanocytes) - the pigment that gives your
skin its color. It can also form in your eye
(intraocular melanoma) and in rare cases in internal
organs such as your intestine. But most melanomas
develop in your skin.
Although they make up the smallest percentage of
all skin cancers, melanomas cause the greatest
number of deaths. That's because they're more likely
than other skin cancers to spread to different parts
of your body (metastasize). The exact cause of all
melanomas isn't clear, but exposure to ultraviolet
(UV) radiation from sunlight or tanning lamps and
beds greatly increases the risk of developing the
Avoiding excessive sun exposure can prevent many
melanomas. And knowing the warning signs of
cancer can help ensure that malignant changes are
detected and treated before they can spread.
Melanoma can be successfully treated if it's caught
Signs and symptoms
Moles the medical term is nevi are clusters of pigmented
cells. Normal moles are generally a uniform color, such as tan, brown or
black, with a distinct border separating the mole from your surrounding
skin. They're oval or round in shape and average about one-quarter inch
(6 millimeters) in diameter the size of a pencil eraser.
Most people have between 10 and 40 moles. Many of these develop by age
20 although they may change in appearance over time and some may even
disappear as you grow older.
Sometimes you may have one or more large (more than one-half inch, or 12
millimeters, in diameter), flat moles with irregular borders and a
mixture of colors, including tan, brown, and either red or pink. Known
medically as dysplastic nevi, these moles are much more likely to become
malignant than normal moles are.
In fact, the first sign of melanoma is often a change in an existing
mole or the development of a new, unusual-looking growth on your skin.
The American Academy of Dermatology has developed an ABCD guide for
determining when a mole is a matter for concern:
A is for
Symmetrical round or oval growths are usually noncancerous (benign).
Be alert for irregular shapes, where one half is different from the
B is for
Have your doctor check moles with notched, scalloped or vaguely
C is for color.
Look for growths that have many colors or an uneven distribution of
color. Growths that have the same overall color are usually benign.
D is for
Consult your doctor if you have any growths that are larger than
one-quarter inch (6 millimeters) about the diameter of a pencil
Other suspicious changes in a mole may include:
Change in texture
for instance, becoming hard or lumpy
pigment from the mole into the surrounding skin
Oozing or bleeding
Cancerous (malignant) moles vary greatly in appearance. Some may show
all of the changes listed above, while others may have only one or two
unusual characteristics. They can also develop on almost any part of
Some melanomas develop on skin that's frequently exposed to the sun such
as your face, lips, hands and arms. You can prevent these by wearing
sunscreen and protective clothing. But the majority of melanomas occur
in less exposed areas. In men they're often found on the back. Women
tend to develop melanomas on their lower legs.
Melanomas can also develop in the spaces between your toes and on your
palms, soles, scalp or genitals. These are sometimes referred to as
hidden melanomas because they occur in places most people wouldn't think
to check. Hidden melanomas include:
This rare form of melanoma occurs under a nail, most often on your
thumb or your big toe. It's especially common in blacks and in other
people with darker skin pigment. The first indication of a subungual
melanoma is usually a brown or black discoloration that's often
mistaken for a bruise (hematoma). See your dermatologist if you
develop a nail discoloration that increases in size or that doesn't
heal after 2 months.
This relatively uncommon type of melanoma develops in the mucosal
tissue that lines the nose, mouth, esophagus, anus, urinary tract
and vagina. Mucosal melanomas are especially hard to detect because
they can easily be mistaken for other, far more common conditions. A
melanoma that develops in your esophagus, for instance, causes pain
that's similar to a sore throat. A melanoma in a woman's genital
tract usually results in itching and bleeding symptoms associated
with a yeast infection or menstrual irregularities. And symptoms of
anorectal melanoma are similar to those caused by hemorrhoids. Your
dentist is trained to spot melanomas that occur in your mouth, so
having regular dental checkups can help catch this type of cancer.
Having regular Pap tests can help spot melanomas in the vagina.
Symptoms of this type of melanoma, which may develop in the lining
of your eyelids (conjunctiva) or the pigmented coating within your
eyeball (choroid), include a scratchy feeling under your eyelid or a
dark spot in your vision. The number of white American men with
conjunctival melanoma have increased greatly over the past 30 years,
most likely as a result of sun exposure. This increase emphasizes
the importance of wearing dark glasses when you're spending time in
Most melanomas occur in more conspicuous places. The most common
spreading melanoma (SSM).
Approximately two-thirds of all melanomas are of this type. An SSM
usually first appears as a flat or slightly raised mark that's dark
with variegated colors and an irregular border. It occurs most often
on the legs in women and on the back and upper arms in men. It can
also occur on the soles or palms, especially in people of African or
Asian descent. Initially, an SSM spreads through the top layer of
skin (epidermis). If it's not caught and treated at this stage, it
eventually begins to grow into the underlying layers of skin the
dermis and fatty layer and may then spread to other parts of your
The most aggressive of all melanomas, NM usually appears as a small,
round bump (nodule) with a smooth border. Most NMs are black,
although some may be brown, blue, gray or even red in color. Because
this type of cancer spreads so rapidly, it's often quite advanced by
the time it's diagnosed.
Acral-lentiginous melanoma (ALM).
The most common skin cancer in people with deeper skin color, such
as blacks and Asians, ALM usually develops on the palms, soles or
nails. It's normally brown or black with irregular borders. Because
ALM is often mistaken for a minor problem, such as a bruise or
blister, it may have penetrated deep into the underlying layers of
skin before it's diagnosed.
The least threatening form of melanoma, LMM tends to develop on the
nose or cheeks of older adults. The lesions are flat and range in
size from 1.2 inches to 2.4 inches (3 centimeters to 6 centimeters)
or more. They tend to be tan, brown or black and generally don't
spread to other parts of the body. Instead, they're likely to spread
in the epidermis for months or even years before spreading to the
deeper layers of skin.
Sometimes people mistake seborrheic keratoses for skin cancer.
Seborrheic keratoses are waxy yellow, brown or black growths that look
as if they've been pasted on your skin. What causes them is unknown, but
they tend to occur in fair-skinned people older than 40. The growths
aren't cancerous, but you may want them removed for cosmetic reasons.
Although it's common to think of skin in cosmetic terms how soft,
smooth or resilient it is your skin is your body's largest organ and
performs a number of essential functions, including protecting you from
temperature extremes, injury and infection.
Your skin consists of three layers the epidermis, dermis and subcutis.
The epidermis, the topmost layer, is as thin as a pencil line. It
provides a protective layer of skin cells that your body continually
sheds. Squamous cells lie just below the outer surface. Basal cells,
which produce new skin cells, are at the bottom of the epidermis. The
epidermis also contains cells called melanocytes, which produce melanin
the pigment that gives skin its normal color. When you're in the sun,
these cells produce more melanin, which helps protect the deeper layers
of skin. The extra melanin is what produces the darker color of a "tan."
Normally, skin cells within the epidermis develop in a controlled and
orderly way. In general, healthy new cells push older cells toward the
skin's surface, where they die and eventually are sloughed off. This
process is controlled by DNA the genetic material that contains the
instructions for every chemical process in your body. But when DNA is
damaged, changes occur in these instructions. One result is that new
cells may begin to grow out of control and eventually form a mass of
Just what damages DNA in skin cells and how this leads to melanoma is
under study. Cancer is a complex disease that often results from a
combination of factors rather than from a single cause. Still, excessive
exposure to ultraviolet (UV) radiation is a leading factor in the
development of melanoma.
UV radiation is a wavelength of sunlight in a range too short for the
human eye to see. Commercial tanning lamps and tanning beds also produce
UV radiation. UV light is divided into three wavelength bands
ultraviolet A (UVA), ultraviolet B (UVB) and ultraviolet C (UVC). Only
UVA and UVB rays reach the earth UVC radiation is completely absorbed
by atmospheric ozone, a naturally occurring substance that filters UV
At one time scientists believed that only UVB rays played a role in the
development of melanoma. And UVB light does cause harmful changes in
skin cell DNA, including the development of oncogenes a type of gene
that can turn a normal cell into a malignant one. But UVA light may also
damage melanocytes. People who visit commercial tanning salons are
especially at risk because tanning lamps and beds mainly produce UVA
Even so, UVB light remains a major concern, especially because of the
ongoing depletion of atmospheric ozone, which normally screens the earth
from some UVB radiation. In the past two decades, ozone levels have, primarily from widespread use of chlorofluorocarbons
(CFCs) synthetic chemicals commonly used as refrigerants, solvents and
foam-blowing agents. Less ozone means that more UVB radiation reaches
Scientists are divided on just how much ozone depletion has contributed
to the rise in skin cancer. They cite other factors, such as an increase
in outdoor activities and sunbathing, as well as a trend toward skimpier
clothing. Yet ozone depletion remains a serious concern.
In addition, the amount of UVB light reaching the earth varies
considerably from one geographic region to another. Rays are strongest
closer to the equator and at high altitudes.
But no matter where you live, your skin absorbs UV radiation whenever
you're outdoors unless you wear protective clothing and sunscreen.
What's more, exposure to occasional periods of intense sunlight puts you
at greater risk of melanoma than spending long hours in the sun. An
initial high dose of UV radiation will severely damage melanocytes, but
not destroy them. When these damaged cells are subjected to further
intense bouts of UVA light, they have little capacity to repair their
DNA and so are more likely to become malignant.
Chronic sun exposure doesn't explain all melanomas. Other factors that
may lead to melanoma include:
A small percentage of people who develop melanoma have a family
history of the disease. Having a parent, child or sibling with
melanoma greatly increases your risk. Damage to the tumor suppressor
gene, p16, appears to play a role in inherited melanomas.
In addition, some
families are affected by a condition called familial atypical
multiple mole and melanoma (FAMMM) syndrome. The hallmarks of FAMMM
include a history of melanoma in one or more close relatives and
having more than 50 moles some of which are atypical. People with
this syndrome have an extremely high risk of developing melanoma.
For that reason, screening for signs of skin cancer is crucial.
Check with your doctor about getting a screening exam every 4 to 6
In general, your risk of developing melanoma increases with age. But
younger people can also develop skin cancer, and melanoma is, in
fact, one of the most common cancers in people under 30.
Complicating matters further, the age at which melanomas tend to
develop appears to be different for men and women. In general, women
have a higher rate of melanoma than men do until age 40. After age
40, the rate for men rises dramatically. Researchers don't yet know
the reason for the disparity, although they believe hormonal factors
may play a role. After age 60, the melanoma rate for women once
again increases. Overall, however, men have a greater lifetime risk
of melanoma than women do.
The American Cancer Society has identified several substances that
may contribute to melanoma, including coal, tar, the pitch used in
road paving, the wood preservative creosote, arsenic compounds in
pesticides and radium.
As with other types of cancer, it's likely that many melanomas result
from a combination of environmental and genetic factors.
Factors that may increase your risk of skin cancer include:
Having less pigment (melanin) in your skin means you have less
protection from damaging UV radiation. If you have blond or red
hair, light-colored eyes and you freckle or sunburn easily, you're
more likely to develop melanoma than someone with a darker
complexion. Fair-skinned people of Northern European ancestry are
particularly at risk. Queensland, Australia, has the highest skin
cancer rate in the world because it has unusually high levels of UV
radiation and because most of its inhabitants are of English or
A history of
Every time you burn your skin, you increase your risk of developing
skin cancer. People who have had one or more severe, blistering
sunburns as a child or teenager are at increased risk of skin cancer
as an adult. For that reason, it's particularly important to protect
children from the sun, not just with sunscreen but also with a hat,
protective clothing and dark glasses. Although sunburns in adulthood
are also a risk factor, the greatest damage seems to occur before
you're 18. Infants are at greatest risk because the melanin in their
skin isn't fully developed.
Exposure to UV radiation is the leading cause of all skin cancers,
including melanoma. Many experts believe that the greatest damage
may occur before age 18. For that reason, it's especially important
to make sure children wear sunscreen or protective clothing when
Living in a sunny climate exposes you to more UV radiation than does
living in a cool, cloudy climate. Skin cancer
is far more common in Arizona than in Minnesota. If you live at a
high elevation, where the sun is stronger, you're also exposed to
more UV radiation.
Having just one dysplastic mole doubles your risk of melanoma.
Having 10 or more increases your risk 12 times. But it's not only
atypical moles that make you more susceptible to melanoma having
more than 50 ordinary moles also increases your risk.
A family or
personal history of skin cancer.
If a close relative, such as a parent, child or sibling, has had
melanoma, you have a greater chance of developing it too. And if
you've had melanoma once, you're more likely to develop it again.
People with weakened immune systems are at greater risk of many
diseases, including skin cancer. This includes people who have
undergone an organ transplant, have certain cancers or HIV/AIDS, or
are taking medications that suppress the immune system.
Exposure to environmental chemicals, including some herbicides,
increases your risk of melanoma.
People with xeroderma pigmentosum, which causes an extreme
sensitivity to sunlight, have a greatly increased risk of developing
Screening and diagnosis
The American Cancer Society (ACS) recommends skin examinations every 3
years for adults between the ages of 20 and 40 and yearly exams for
everyone older than 40. These screening exams involve a head to toe
inspection of your skin by someone qualified to diagnose skin cancer
such as a dermatologist or nurse specialist. If you have risk factors
for skin cancer fair skin, a history of severe sunburns, one or more
dysplastic moles, or a family history of melanoma talk to your doctor
about more frequent screenings. Some doctors believe that all close
family members of a person with melanoma also should be screened.
In addition, the ACS recommends monthly self-exams for everyone older
than 18. This helps you learn the moles, freckles and other skin marks
that are normal for you, so you can notice any unusual changes. It's
best to do this standing in front of a full-length mirror while using a
hand-held mirror to inspect hard to see areas. Be sure to check the
fronts, backs and sides of your arms and legs; your groin, scalp and
fingernails; and your soles and the spaces between your toes.
If you notice a new skin growth, a change in an existing mole or a sore
that doesn't heal in 2 weeks, see your doctor. He or she may suspect
cancer by simply looking at your skin, but the only way to accurately
diagnose melanoma is with a biopsy. In this procedure, your doctor or
dermatologist removes all or part of the suspicious mole or growth, and
a pathologist analyzes the sample. Sometimes more than one pathologist
may examine the tissue to determine whether cancer is present.
If your mole is small, your doctor is likely to perform an excisional
biopsy such as a punch biopsy or an elliptical excision. In this
procedure, the entire mole or growth is removed, along with a small
border of normal-appearing skin. On the other hand, your doctor might
use an incisional biopsy for large moles, or for those on your hands or
face, where scars are more obvious. In that case, only the most
irregular part of a mole or growth is taken for laboratory analysis.
you receive a diagnosis of melanoma, the next step is to determine the
extent, or stage, of the cancer. Melanoma is staged using these
A pathologist determines the thickness and depth of a melanoma by
carefully examining it under a microscope. The depth of a cancerous
lesion is the most important factor in deciding on a treatment plan.
In general, the deeper the tumor, the more serious the disease.
It's also important to determine whether melanoma cells have invaded
your lymph nodes. To do so, your surgeon may use a procedure known
as a sentinel node biopsy. Until recently, surgeons would remove as
many lymph nodes as possible to verify that the nodes didn't contain
cancer cells. But this greatly increased the risk of lymphedema
severe swelling of the involved area and other side effects.
That's why a procedure was developed that focuses on finding the
sentinel nodes the first nodes to receive the drainage from
malignant tumors and therefore the first to develop cancer. If a
sentinel node is removed, examined and found to be healthy, the
chance of finding cancer in any of the remaining nodes is small and
no other nodes need to be removed. This spares you the risks of more
Melanoma is staged using the numbers 0 through IV:
This melanoma is also called in situ (in one place) melanoma.
At this stage, the cancer is confined to the epidermis and hasn't
begun to spread. Finding and treating a cancerous tumor at this
stage offers the best chance for a full recovery.
These cancers are invasive tumors that have the ability to spread to
other areas. A stage I cancer is small and well localized and has a
very successful treatment rate. But the higher the stage number, the
lower the chances of a full recovery. By stage IV, the cancer has
spread beyond your skin to other organs, such as your lungs, liver
and bone. Although it may not be possible to eliminate the cancer at
this stage, treatment with radiation or biological or experimental
therapies may help alleviate symptoms the cancer is causing.
The best treatment for you depends on the stage of cancer you have and
your age, overall health and personal preferences. But in most cases,
the standard treatment for melanomas that haven't spread beyond the skin
is surgery to remove the cancer.
When melanoma has spread to another part of your body, options may
include surgery, chemotherapy, radiation therapy, biological therapy,
experimental therapy or a combination. It's important to understand the
different treatments and their potential risks and side effects. Don't
be afraid to discuss any questions you may have with your treatment
team. You may also want to consider seeking a second opinion, especially
from doctors who specialize in treating melanoma. In some cases, after
weighing your options you may choose not to treat the melanoma itself
but rather to try to relieve any symptoms the cancer may cause.
Treating early-stage melanomas
The best treatment for early-stage melanomas is surgical removal (simple
excision). Very thin melanomas may have been entirely removed during the
biopsy and require no further treatment. Otherwise, surgery involves
your doctor excising the cancer as well as a small border of normal skin
and a layer of tissue beneath the skin. In almost every case this
eliminates the cancer.
At one time, surgery for more invasive early-stage tumors involved
cutting out the cancer along with a large border of normal skin (wide
local excision). This usually meant having a skin graft a procedure in
which skin from another part of the body is used to replace the skin
that's removed. But taking smaller amounts of normal skin in some cases
of invasive melanomas may be just as effective in treating cancer and
may eliminate the need for skin grafts.
Even so, you may be concerned about scarring. It may help to know that
in many cases, the scar is a small line about 1 to 2 inches long that
fades with time. If you need a skin graft, however, the scar will be
larger and more noticeable.
Treating melanomas that have spread beyond the skin
Unfortunately, it's usually not possible to cure melanomas that have
spread beyond the skin. But surgically removing a metastatic
melanoma can often provide relief of symptoms sometimes for years.
Whether this is an option for you depends on where the cancer is
located and how severe it is, as well as on your own wishes and
This form of treatment uses drugs to destroy cancer cells. Two or
more drugs are often given in combination and may be administered
intravenously, in pill form or both usually for 4 to 6 months.
Although not as effective in treating melanoma as some other types
of cancer, chemotherapy can help relieve symptoms in people with
advanced metastatic melanoma.
generally a systemic therapy, which means that it can affect cancer
cells throughout your body. But chemotherapy also affects healthy
cells especially fast-growing cells in your digestive tract, hair
and bone marrow. This can cause side effects such as nausea,
vomiting and fatigue. Not everyone has these side effects, however,
and there are now better ways to manage them if you do.
studying different ways to administer chemotherapy medications in an
attempt to reduce their effect on healthy cells. One method under
investigation is limb perfusion. It's used for melanomas on the arm
or leg. In this procedure, the blood flow to the limb being treated
is temporarily stopped with a tourniquet. High doses of chemotherapy
drugs are then injected directly into the melanoma. Because most of
the drugs stay in the limb, they're less likely to affect other
parts of the body.
This treatment uses high-energy X-rays to kill cancer cells. It's
sometimes used to help relieve symptoms of melanoma that has spread
to another organ. Fatigue is a common side effect of radiation
therapy, but your energy usually returns once the treatment is
This form of treatment is designed to help your immune system fight
disease. It involves the use of biologic response modifiers (BRMs)
substances your body normally produces in response to infection.
BRMs such as interleukin-2 and interferon are now produced in
laboratories for use in treating cancer and other diseases. Side
effects include symptoms similar to those of the flu, such as
chills, fever, nausea, vomiting and diarrhea. Often, these symptoms
are so severe you need to be hospitalized. For that reason,
researchers are searching for forms of immunotherapy that not only
are more effective but also cause fewer side effects.
The most heartening news about melanoma is that many cases of skin
cancer can be prevented simply by following these precautions:
Avoid the sun
between 10 a.m. and 3 p.m.
Because the sun's rays are strongest during this period, try to
schedule outdoor activities for other times of the day, even in
winter or when the sky is cloudy. You absorb UV radiation
year-round, and clouds offer little protection from damaging rays.
summer and winter.
Sunscreens don't filter out all harmful UV radiation, especially the
radiation that can lead to melanoma. But they play a major role in
an overall sun protection program. Be sure to use a broad-spectrum
sunscreen with a sun protection factor (SPF) of at least 15 when you
go outside, summer and winter. Broad-spectrum products provide
protection against both UVA and UVB radiation. Use sunscreen on all
exposed skin, including your lips, the tips of your ears, and the
backs of your hands and neck. You need to use about an ounce of
sunscreen to adequately cover your entire body.
For the most
protection, apply sunscreen 30 minutes before sun exposure and
reapply it every 2 hours throughout the day. Also be sure to reapply
it after swimming or exercising. Apply sunscreen to young children
before they go outdoors, and teach older children and teens how to
use sunscreen to protect themselves. Keep sunscreen in your car as
well as with your gardening tools and sports and camping gear to
remind yourself and your family to use it.
Be an educated
Most sunscreens provide physical protection, chemical protection or
a combination of both. Knowing the difference can help you select
the best product for you and your family.
sunscreens contain ingredients such as titanium dioxide. These form
an opaque film that reflects UV rays before they can penetrate your
skin. Chemical sunscreens, on the other hand, absorb sunlight before
it can cause any damage. Combination products do a little of both.
Even if you know
what to look for, sunscreen labels can be confusing, and sometimes
actually misleading. That's why the Food and Drug Administration has
instituted new labeling guidelines. Among the changes is the
elimination of the terms sun block (no product actually
"blocks" UV rays), all-day (no sunscreen lasts all day) and
waterproof (all sunscreens wash off in water to some extent
the new term is water-resistant). Sunscreens claiming an SPF
higher than 30 are now labeled 30+, rather than 45 or 60, because
tests show little difference among products with SPF factors over
30. Finally, make sure any product you use actually contains
sunscreen many tanning oils and lotions don't. Products that don't
contain sunscreen are required by law to clearly indicate that on
Sunscreens don't provide complete protection from UV rays. That's
why it's a good idea to also wear dark, tightly woven clothing that
covers your arms and legs, and a broad-brimmed hat, which provides
more protection than a baseball cap or visor. Some companies also
design photoprotective clothing. Your dermatologist can recommend an
appropriate brand. Don't forget sunglasses. Look for those that
block out both UVA and UVB rays.
beds and tan-accelerating agents.
Tanning beds emit UVA rays, which may be as dangerous as UVB rays,
especially since UVA light penetrates deeper into your skin and
causes precancerous skin lesions.
Be aware of
Some common prescription and over-the-counter drugs including
antibiotics; certain cholesterol, high blood pressure and diabetes
medications; birth control pills; nonsteroidal anti-inflammatories
such as ibuprofen (Advil, Motrin, others); and the acne medicine isotretinoin (Accutane) can make your skin more sensitive to
sunlight. Ask your doctor or pharmacist about the side effects of
any medications you take. If they increase your sensitivity to
sunlight, be sure to take extra precautions.
See your doctor for a complete skin exam every year if you're older
than 40, or more often if you're at high risk of developing
Check your skin
regularly and report changes to your doctor.
Examine your skin often for new skin growths or changes in existing
moles, freckles, bumps and birthmarks. With the help of mirrors,
check your face, neck, ears and scalp. Examine your chest and trunk,
and the tops and undersides of your arms and hands. Examine both the
front and back of your legs, and your feet, including the soles and
the spaces between your toes. Also check your genital area,
including between your buttocks.
high blood pressure
Complementary and alternative medicine
Alternative medicine refers to therapies that may be used instead of
conventional treatments. Complementary or integrative medicine, on the
other hand, usually means therapies used in conjunction with traditional
treatments. These distinctions aren't firm, however, and the boundaries
between types of therapies are constantly changing.