|
General Information About Melanoma
| Key Points for This Section
|  |
Melanoma is a disease in which malignant (cancer) cells form in
the skin cells called melanocytes (cells that color the skin).
Melanocytes are found
throughout the lower part of the epidermis. They produce
melanin, the
pigment that gives skin its natural
color. When skin is exposed to the sun, melanocytes produce more pigment,
causing the skin to tan, or darken.
The skin is the body’s largest organ. It protects against heat,
sunlight, injury, and infection. The
skin has 2 main layers: the epidermis (upper or outer layer) and the
dermis (lower or inner layer).
When melanoma starts in
the skin, the disease is called cutaneous melanoma. This PDQ summary is about
cutaneous (skin) melanoma. Melanoma may also occur in the eye and is called
intraocular or ocular melanoma. (Refer to the PDQ summary on
Intraocular (Eye) Melanoma
Treatment for more information.)
There are 3 types of skin cancer:
Melanoma is more aggressive than basal cell skin cancer or squamous
cell skin cancer. (Refer to the PDQ summary on
Skin Cancer Treatment
for more information on basal cell and squamous cell skin cancer.)
Melanoma can occur anywhere on the body.
In men,
melanoma is often found on the trunk (the area from the shoulders to the hips)
or the head and neck. In women, melanoma often develops on the arms and legs.
Melanoma usually occurs in adults, but it is sometimes found in children and
adolescents.
Unusual moles, exposure to sunlight, and health history can
affect the risk of developing melanoma.
Risk factors include the
following:
- Unusual moles.
- Exposure to natural sunlight, including sunburns during
childhood.
- Exposure to artificial ultraviolet light (tanning
booth).
- Family or personal history of melanoma.
- Red or blond hair.
- White or light-colored skin and freckles.
- Blue eyes.
Possible signs of melanoma include a change in the appearance
of a mole or pigmented area.
These and other symptoms may be caused by melanoma or by other
conditions. A doctor should be consulted if any of the following problems
occur:
- A mole that:
- changes in size, shape, or color.
- has irregular edges or borders.
- is more than 1 color.
- is asymmetrical (if the mole is divided in half, the 2
halves are different in size or shape).
- itches.
- oozes, bleeds, or is ulcerated (a hole forms in the skin when the top layer of cells breaks down and the underlying tissue shows through).
- Change in pigmented (colored) skin.
- Satellite moles (new moles that grow near an existing
mole).
Tests that examine the skin are used to detect (find) and
diagnose melanoma.
If a mole or pigmented area of the skin changes or looks abnormal,
the following tests and procedures can help detect and diagnose
melanoma:
- Skin examination: A doctor or nurse examines the skin to look
for moles, birthmarks, or other pigmented areas that look abnormal in color,
size, shape, or texture.
- Biopsy: A
local excision is done to remove as
much of the suspicious mole or lesion as possible. A pathologist then looks at the
tissue under a microscope to check
for cancer cells. Because melanoma can be hard to diagnose, patients should consider having their biopsy sample checked by a second pathologist.
Suspicious areas should not be shaved off or
cauterized (destroyed with a hot
instrument, an electrical current, or a caustic substance).
Certain factors affect prognosis (chance of recovery) and treatment options.
The prognosis (chance of recovery) and treatment options depend on
the following: - The stage of melanoma (whether cancer is
found in the outer layer of skin only, or has spread to the
lymph nodes or to other places in
the body).
- Whether there was bleeding or ulceration at the
primary site.
- The location and size
of the tumor.
- The patient’s
general health.
Although many people are successfully treated, melanoma can
recur (come back).
 Back to Top
Next Section > |
