Skin cancer is when cancer cells grow in the skin.

The two most common kinds of skin cancer are:

  • Basal cell carcinoma —This is the most common type of skin cancer. Basal cell carcinoma develops in the outermost layer of skin. This cancer usually grows slowly and does not spread to other tissues in the body.
  • Squamous cell carcinoma —This cancer develops in the uppermost layer of skin cells. Squamous cell carcinoma usually grows slowly. However, in some cases it can grow fast and spread to other tissues in the body. If treated early this type of cancer is rarely fatal. However, the cancer can be fatal if it spreads beyond the skin.

Basal Cell Carcinoma
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It is important that skin cancers be found and treated early. If left untreated, they can quickly invade and destroy nearby tissue.

Cancer occurs when skin cells in the body divide without control or order. When cells keep dividing uncontrollably when new cells are not needed, a mass of tissue forms. This is called a growth or tumor. Unlike benign tumors, malignant tumors can invade nearby tissues and spread to other parts of the body.