Definitions:
Birthmark - skin marking present at birth that ranges in color from brown or black to bluish or blue-gray. Birthmarks include cafe-au-lait spots, moles, and mongolian spots. (See also red birthmarks.)

Skin cancer - the uncontrolled growth of skin cells. If left unchecked, these cancer cells can spread from the skin into other tissues and organs. There are different types of skin cancer. Basal cell carncinoma is the most common. Melanoma is less common, but more dangerous.

Red birthmarks - colored, vascular (blood vessel) skin markings that develop before or shortly after birth.

Sunburn - occurs when skin is burned by exposure to the sun or other ultraviolet light.

Sunburn first aid - Sunburn is from over-exposure to the harmful ultraviolet rays of the sun. While the symptoms are usually temporary (such as red skin that is painful to the touch), the skin damage is often permanent and can have serious long-term health effects, including skin cancer.

                                                                                                                                 Return to Top

Causes, incidence, and risk factors:
The outer layer of skin, the epidermis, is made up of different types of cells. Skin cancers are classified by the types of epidermal cells involved:

Basal cell carcinoma develops from abnormal growth of the cells in the lowest layer of the epidermis and is the most common type of skin cancer.
Squamous cell carcinoma involves changes in the squamous cells, found in the middle layer of the epidermis.
Melanoma occurs in the melanocytes (cells that produce pigment) and is less common than squamous or basal cell carcinoma -- but more dangerous. It is the leading cause of death from skin disease.
Skin cancers are sometimes classified as either melanoma or nonmelanoma. Basal cell carcinoma and squamous cell carcinoma are the most common nonmelanoma skin cancers. Other nonmelanoma skin cancers are Kaposi's sarcoma, Merkel cell carcinoma, and cutaneous lymphoma.


Skin cancer is the most common form of cancer in the Unites States. Known risk factors for skin cancer include the following:

Complexion - Skin cancers are more common in people with light-colored skin, hair, and eyes.
Genetics - Having a family history of melanoma increases the risk of developing this cancer.
Age - Nonmelanoma skin cancers are more common after age 40.
Sun exposure and sunburn - Most skin cancers occur on areas of the skin that are regularly exposed to sunlight or other ultraviolet radiation. This is considered the primary cause of all skin cancers.
Skin cancer can develop in anyone, not only people with these risk factors. Young, healthy people -- even those with with dark skin, hair, and eyes -- can develop skin cancer.

Symptoms:
Skin cancers may have many different appearances. They can be small, shiny, or waxy, scaly and rough, firm and red, crusty or bleeding, or have other features. Therefore, anything suspicious should be looked at by a physician. See the individual articles on specific skin cancers for more information.

Here are some features to look for:

Asymmetry: one half of the abnormal skin area is different than the other half
Borders: irregular borders
Color: varies from one area to another with shades of tan, brown, or black (sometimes white, red, blue)
Diameter: usually (but not always) larger than 6mm in size (diameter of a pencil eraser)
Use a mirror or have someone help you look on your back, shoulders, and other hard-to-see areas.

Treatment:
Different types of skin cancer require different treatment approaches. Three specific types of skin cancer are:

• Basal cell carcinoma - the most common form of skin cancer caused mainly by chronic exposure to sunlight.
• Squamous cell carcinoma - the second most common form of skin cancer caused mainly by sun exposure, but also occurs where skin has suffered certain kinds of injury: burns, scars, long-standing sores, sites previously exposed to X-rays or certain chemicals (such as arsenic and petroleum by-products).
• Melanoma - the most serious form of skin cancer but if diagnosed while it's still limited to the outermost skin layer, it is almost 100% curable. Melanoma is a malignant tumor that originates in melanocytes, the cells which produce the pigment melanin that colors our skin, hair, and eyes and is heavily concentrated in most moles.

Discuss treatments options with your physician for each type of skin cancer.

Support Groups
The following organizations are good resources for information on cancer:

Expectations (prognosis):
The outlook depends on a number of factors, including the type of cancer and how quickly it was diagnosed. See the specific skin cancer articles for additional information.

Calling your health care provider:
Any suspicious mole, sore, or skin growth should be looked at by a physician immediately. Take any changes in a mole or sudden growth of a skin lesion seriously.

Prevention:
Minimizing sun exposure is the best way to prevent skin damage, including many types of skin cancer:

Protect your skin from the sun when you can -- wear protective clothing such as hats, long-sleeved shirts, long skirts, or pants.
Try to avoid exposure during midday, when the sun is most intense.
Use sunscreen with an SPF of at least 15. Apply sunscreen at least one-half hour before sun exposure, and reapply frequently.
Apply sunscreen during winter months as well.