What is Skin Cancer?
Skin cancer is an abnormal growth of skin cells in the skin. The most common affected layer of the skin affected by skin cancer is the top layer – the epidermis. This superficial top layer of skin is more susceptible to the damaging effects of ultraviolet radiation causing a mutation in the cells DNA. The mutation makes the skin cells start to grow uncontrollably, forming eventually the accumulation of cancer cells that appear in the skin.
The type of skin cancer that develops depends on what kind of cell in the skin has been affected and started the mutation. The epidermis contains three main types of cells:
- The most superficial surface of the skin is made up of densely packed cells, known as squamous cells.
- At the bottom of the epidermis is a layer called the basal layer, made up of predominantly basal cells. These basal cells divide and turn into squamous cells that migrate towards the skin surface.
- In the basal cell layer are also pigmented cells called melanocytes – they produce the pigment melanin which protects squamous cells against too much sun. The melanin in our skin provides a darker color.