Skin cancer symptoms: what to look for and when to see a GP

Cancer Research UK explains that there are two main types: non-melanoma skin cancer and melanoma. Non-melanoma skin cancer includes basal cell carcinoma and squamous cell carcinoma, together with other rare types, while melanoma develops from skin cells called melanocytes. The NHS says non-melanoma skin cancer can usually be effectively treated, and that melanoma is the more serious type.

The British Association of Dermatologists adds that non-melanoma skin cancer accounts for 90% of all skin cancers, and that basal cell carcinoma is the most common. Because the group is broad, appearance varies, which is why the safest rule is to have anything new, changing or persistent checked rather than trying to identify the type yourself.

The NHS says the main symptom is a growth or unusual patch on the skin. Any part can be affected, but it is most common in areas exposed to the sun: the head, face and ears, neck and shoulders, back, hands and lower legs. The growths or patches vary in colour, size and texture. Some are raised and smooth with clear edges, others are bumpier, rough or crusty, and some begin as a flat discoloured patch. They can be purple, brown or red, may be darker on brown or black skin, and sometimes look crusty and feel rough or itchy.

Cancer Research UK lists a sore that does not heal, and an area of skin that looks unusual, red, itchy, bleeds or scabs for more than 4 weeks. The NHS advice is to see a GP if a growth is getting bigger or has changed colour or texture, or if a growth or area of skin hurts, itches, bleeds, crusts or scabs for more than 4 weeks. Finding non-melanoma skin cancer early can mean it is easier to treat.

• A growth or patch that is getting bigger.

• Raised, smooth growth with clear edges, or a rough, crusty one.

• A sore that does not heal.

• Skin that hurts, itches, bleeds, crusts or scabs for more than 4 weeks.

A new mole or a change in an existing mole may be a sign of melanoma, according to the NHS. Melanomas can appear anywhere on the body but are more common on areas often exposed to the sun, and rarer types can affect the eyes, soles of the feet, palms or genitals. The NHS suggests checking your skin with a mirror or asking a partner or friend to check areas you cannot see.

Normal moles are usually round with smooth edges, one colour and small, often about the size of a pencil end or smaller. Melanomas are often an uneven shape, with two different halves and uneven edges, a mix of two or more colours, and bigger, often more than 6mm wide, though they can be smaller when diagnosed early. A mole that changes in size, shape or colour may be a melanoma, as may one that is swollen and sore, bleeding, itchy or crusty.

See a GP if you have a mole that has changed size, shape or colour; a mole that is painful or itchy; a mole that is inflamed, bleeding or crusty; a new or unusual mark that has not gone away after a few weeks, including on the palms or soles; or a dark area under a nail not caused by an injury.

The NHS says the GP may ask about your health, your symptoms and how much time you spend in the sun, and will want to know if the area has changed recently and whether you or your family have had skin cancer. The GP looks at the area and may ask to take a photograph to send to a dermatologist, which is called teledermatology for moles. If the GP thinks the symptoms could be cancer you may get an urgent referral for tests or to see a specialist in hospital; the NHS stresses this does not definitely mean you have cancer.

The specialist checks your skin and asks about changes you have noticed, and may use a magnifying device to look at the skin more closely. They may recommend cutting out a small area of affected skin and sending it to a laboratory, which is called an excision biopsy. The NHS says non-melanoma biopsy results should arrive within 2 to 4 weeks and that you can contact the hospital or GP if you are worried about waiting. If skin cancer is found, further tests such as scans or lymph gland checks are only needed in some cases: basal cell carcinoma rarely spreads, so more tests are needed only if it is very large, while squamous cell carcinoma sometimes spreads.

For non-melanoma skin cancer the NHS says surgery is the main treatment, especially if found early, with radiotherapy, targeted medicines, photodynamic therapy and chemotherapy sometimes used. Surgery may involve cutting out the cancer with some surrounding healthy skin, or freezing the affected skin (cryosurgery); a skin graft may be needed if a large area is removed. Radiotherapy may be used if the cancer covers a large area, is difficult to reach surgically or the person is too unwell for surgery. A chemotherapy cream is sometimes used for cancers affecting only the top layer of skin, usually once or twice a day for 3 to 4 weeks.

You will have regular check-ups during and after treatment, and the NHS says you do not need to wait for your next check-up if you are worried about symptoms or side effects. The care team includes a clinical nurse specialist as your main contact. Melanoma treatment depends on stage and is planned by a specialist team.

Ultraviolet (UV) light, from the sun and from sunbeds, is the most common cause of non-melanoma skin cancer. The NHS lists higher risk for people with pale skin that burns easily, red or fair hair, blue or green eyes, many freckles or moles, a lot of past sun exposure or sunburn, heavy sunbed use, or a personal or family history of skin cancer. If you have brown or black skin you have a lower chance of non-melanoma skin cancer but can still get it.

The NHS advice is to stay out of the sun during the hottest part of the day (11am to 3pm in the UK), keep arms and legs covered, wear a wide-brimmed hat and UV-protective sunglasses, use sunscreen with SPF of at least 30 and at least 4-star UVA protection and reapply it regularly, and protect babies and children whose skin is much more sensitive.

Via the NHS, a suspicious skin lesion is assessed by a GP, then referred urgently to dermatology if cancer is suspected. The British Association of Dermatologists notes that the NHS aims for a specialist appointment within 2 weeks of an urgent referral, which may be in person or by clinical photographs.

Private dermatologists and plastic surgeons can see people quickly, examine lesions with a dermatoscope and remove lesions with a biopsy sent for NHS-standard pathology. Private mole mapping services exist, but any suspicious lesion should still be removed and examined by a pathologist, and any cancer diagnosis should be managed by a multidisciplinary team.