The skin

The skin has many purposes. It:

  • protects the body from injury and infection
  • helps to control body temperature
  • helps to control fluid loss
  • gets rid of waste substances through the sweat glands.

The skin is divided into two main layers. The outer layer is the epidermis and the layer underneath is the dermis. Below these is a deeper layer of fatty tissue.

The epidermis contains three types of cells. Most of the epidermis is filled with cells known as squamous cells. At the base of the squamous cells are rounder cells called basal cells. In between the basal cells are other cells called melanocytes. Melanocytes produce the pigment melanin. It is this pigment that gives skin its colour.

The structure of the skin
The structure of the skin

View a large version

Read a description of this image

Back to Understanding skin cancer

What is cancer?

There are more than 200 different kinds of cancer, each with its own name and treatment.

Types of skin cancer

The two most common types of skin cancer are basal cell carcinoma and squamous cell carcinoma.

Why do cancers come back?

Sometimes, tiny cancer cells are left behind after cancer treatment. These can divide to form a new tumour.