Skin cancer develops when damage to the DNA within skin cells causes them to grow and divide in an uncontrolled way. This damage is most commonly caused by ultraviolet (UV) radiation from sunlight or artificial sources such as sunbeds. Skin cancer is the most common form of cancer in the UK, but most cases can be treated successfully when diagnosed and treated early.
Skin cancer occurs when abnormal changes develop within skin cells, causing them to grow and multiply uncontrollably. Instead of following the normal cycle of growth and replacement, damaged cells continue dividing and may eventually form a cancerous lesion or tumour.
Skin cancer is the most common form of cancer in the UK. Each year, there are around 156,000 cases of non-melanoma skin cancer and approximately 19,000 to 20,000 cases of melanoma diagnosed across the UK. Most cases are linked to cumulative exposure to ultraviolet (UV) radiation from sunlight or sunbeds. 1
Skin cancer can affect people of all ages and skin tones. Although it most commonly develops on areas exposed to sunlight, it can occur anywhere on the body, including areas that receive little or no sun exposure.
Many skin cancers are slow growing and highly treatable when detected early. However, some forms can grow deeper into the skin, spread to nearby lymph nodes or affect other parts of the body if left untreated.
IMPORTANT: The images on this page are for illustrative purposes only. Skin cancers can vary in appearance depending on the type, location, skin tone and stage of development. Some may resemble harmless skin conditions such as moles, eczema or psoriasis. If you notice a new, changing or unusual skin lesion, seek professional assessment.
Skin cancer is the most common form of cancer in the UK. The majority of cases are non-melanoma skin cancers, primarily basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). Melanoma is less common but is generally considered more serious because it is more likely to spread if not diagnosed early.
The primary cause of skin cancer is exposure to ultraviolet (UV) radiation.
UV radiation damages the DNA within skin cells. Over time, repeated exposure can overwhelm the skin’s natural repair mechanisms, allowing abnormal cells to survive and multiply.
Sources of UV radiation include:
Other factors that may increase risk include:
Anyone can develop skin cancer. However, the risk is higher in people who:
People with darker skin tones can also develop skin cancer, although it is generally less common.
Skin cancer most often develops on areas exposed to the sun, including the face, scalp, ears, neck, arms and hands. It can also occur on areas that receive little sun exposure, such as the palms, soles of the feet, nails and genital skin, particularly in melanoma.
Basal cell carcinoma (BCC) is the most common type of skin cancer in the UK. It develops from basal cells within the lower part of the epidermis and usually grows slowly. BCC rarely spreads to other parts of the body, but it can damage surrounding skin and deeper tissues if left untreated.
Common locations: Nose, cheeks, eyelids and ears.
Common signs include:
Squamous cell carcinoma (SCC) is the second most common type of skin cancer in the UK. It develops from squamous cells within the outer layer of the skin and can grow deeper into surrounding tissues. In some cases, SCC can spread to nearby lymph nodes or other parts of the body.
Common locations: Scalp, ears, lips and the backs of the hands.
Common signs include:
Melanoma develops from melanocytes, the pigment-producing cells that give skin its colour. Although less common than BCC and SCC, melanoma is considered the most serious form of skin cancer because it is more likely to spread to other parts of the body if not detected and treated early.
Common locations: Back, legs, arms or any site where a new or changing mole develops.
Common signs include:
Less common skin cancers include:
These cancers are uncommon and usually require specialist assessment and treatment.
Bowen’s disease is the earliest form of squamous cell carcinoma (SCC), where abnormal cells are confined to the outer layer of the skin. It commonly appears on the lower legs, forearms and trunk as a persistent red, scaly patch and is usually highly treatable.
Actinic keratoses are precancerous patches caused by long-term sun exposure, most commonly affecting the face, scalp, ears and backs of the hands. While most remain harmless, a small proportion can develop into squamous cell carcinoma over time and indicate significant cumulative UV damage.
Lentigo maligna is the earliest stage of melanoma, where abnormal pigment cells are confined to the outer layer of the skin. It most commonly develops on chronically sun-exposed areas such as the face and scalp in older adults and typically appears as a slowly enlarging, irregularly pigmented patch.
Skin cancer does not always cause pain or discomfort. Possible signs include:
Changes may develop slowly over time and may not cause symptoms initially.
Seek assessment for skin changes such as:
Melanoma often appears as a new mole or a change in an existing mole. The ABCDE guide can help identify concerning features:
Specialists combine clinical assessment, dermoscopy and, where needed, biopsy and laboratory testing to assess suspicious moles and skin lesions and determine whether further investigation is required.
Key diagnostic steps:
Skin cancer screening can help identify concerning changes early and provide clear guidance on monitoring, investigation or treatment where needed.
Imaging such as ultrasound, CT, MRI or PET scans may occasionally be used when there is concern that a cancer has spread beyond the skin. This is generally reserved for selected cases of melanoma, advanced SCC or other high-risk skin cancers.
Treatment depends on the type, location, size, and stage of the cancer, as well as the patient’s overall health and preferences.
The outlook depends on the type of skin cancer and how early it is diagnosed.
Yes. People who have had skin cancer have a higher risk of recurrence or developing a new skin cancer, which is why follow-up and regular skin checks are important.
Not all skin cancers can be prevented, but the risk can be significantly reduced through good sun protection habits.
Helpful measures include:
Becoming familiar with your skin can help you recognise new or changing lesions more easily.
Any mole, patch or skin lesion that changes in size, shape, colour or texture, or fails to heal, should be assessed by a healthcare professional.
If a mole or skin lesion changes in size, shape, colour, or becomes painful, seek professional assessment promptly. Aventus Clinic offers a free online skin cancer evaluation to provide expert, personalised guidance and treatment options.
