Skin cancer is the uncontrolled growth of abnormal 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 carcinoma is the most common. Melanoma is less common, but more dangerous.
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:
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:
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.
Skin cancers may have many different appearances. They can be small, shiny, 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 articles on specific skin cancers for more information.
Here are some features to look for:
Use a mirror or have someone help you look on your back, shoulders, and other hard-to-see areas.
Different types of skin cancer require different treatment approaches. Surgical removal of the cancer is very common.
See the specific type of skin cancer for information:
For additional resources, see cancer support group.
The outlook depends on a number of factors, including the type of cancer and how quickly it was diagnosed. Basal cell carcinoma and squamous cell carcinoma rarely spread to other parts of the body. However, melanoma is more likely to spread. See the specific skin cancer articles for additional information.
Any suspicious mole, sore, or skin growth should be looked at by a physician immediately. You should take seriously any changes in a mole or any sudden growth on the skin.
Minimizing sun exposure is the best way to prevent skin damage, including many types of skin cancer:
Cancer - skin