Skin cancer

Alternative Names

Cancer – skin

Definition of Skin cancer

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.

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:


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.


Different types of skin cancer require different treatment approaches. Surgical removal of the cancer is very common.

Expectations (prognosis)

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.


Jonathan Kantor, MD, North Florida Dermatology Associates, Jacksonville, FL. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc. – 8/12/2009

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ADAM Medical Encyclopedia

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