What is melanoma?

Melanoma is a cancer that usually starts in the skin. There are other types of skin cancer known as non-melanoma skin cancers. These include basal cell carcinoma (rodent ulcer) and squamous cell carcinoma.

Melanoma can start in a mole or in normal-looking skin. About half of all melanomas start in normal-looking skin.

The number of people developing melanoma is rising. Each year, about 14,500 people in the UK are diagnosed with melanoma. In the UK, melanoma is slightly more common in women than in men. It is one of the most common cancers in people aged 15 to 34. But, like most cancers, it is more common in older people.

People with dark skin are much less likely than people with fair skin to get melanoma. This is because their skin has more natural protection.

How melanoma develops

Melanoma develops from melanocytes that start to grow and divide more quickly than usual. In melanoma, the melanocytes also start to spread into the surrounding surface layers of skin. When they grow out of control, they usually look like a dark spot or an unusual-looking mole on your skin.

It is important to find and treat melanoma as early as possible. If a melanoma is not removed, the cells can grow down deeper into the layers of the skin. These layers contain tiny blood vessels and lymphatic vessels. If the melanoma cells get into the blood or lymphatic vessels, they can travel to other parts of the body.

Early-stage or thin melanomas are unlikely to spread into the blood or lymphatic vessels. They are usually cured with surgery.

We have more information about the different stages of melanoma.

Back to Understanding melanoma

Cancer and cell types

Cancers are grouped into types. Types of cancer often behave and respond to treatments in different ways.

How is it treated?

There are five main types of cancer treatment. You may receive one, or a combination of treatments, depending on your cancer type.

The skin

The skin is divided into two main layers - the outer layer (epidermis), and a layer underneath (dermis).

Why do cancers come back?

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