Mole changes to check: when a mole needs a GP and what happens next

The NHS says moles are small coloured spots on the skin that most people have, usually nothing to worry about unless they change size, shape or colour. Most are round or oval with a smooth edge, can be flat or raised, may feel smooth or rough and sometimes have hair growing from them. They are usually darker on brown and black skin.

It is normal for babies to be born with moles, for new moles to appear (especially in children and teenagers), for moles to fade or disappear as you get older, and for moles to get slightly darker in pregnancy.

The NHS melanoma symptoms page explains that a new mole or a change in an existing mole may be a sign of melanoma, which can appear anywhere but is more common on skin often exposed to the sun. Rarer types can affect the eyes, soles of the feet, palms of the hands or genitals. It describes four areas to look at.

• Shape and edge: normal moles are usually round with smooth edges; melanomas are often uneven, may have two different halves and uneven edges.

• Colour: normal moles are usually one colour; melanomas often have a mix of 2 or more colours.

• Size: melanomas tend to be bigger, often more than 6mm wide, but can be smaller if diagnosed early.

• Change over time: a mole that changes size, shape or colour may be a melanoma; also look for moles that are swollen and sore, bleeding, itchy or crusty.

The NHS suggests checking your skin for unusual changes, using a mirror or asking a partner or friend to check areas you cannot see. It is helpful to look at your whole body regularly, including the scalp, soles, between the toes and under nails, so that new or changing marks stand out. Photographs taken in the same light each month give you something to compare against.

The NHS advises seeing a GP if you have a mole that has changed size, shape or colour; is painful or itchy; is inflamed, bleeding or crusty; if you have a new or unusual mark on the skin that has not gone away after a few weeks, including on the palms or soles; or if you have a dark area under a nail not caused by an injury. It stresses that finding a melanoma as early as possible can mean it is easier to treat.

At the appointment you will be asked about your health, family history, medical conditions and symptoms; tell the GP about any mole or freckle that has recently changed and about any personal or family history of skin cancer. The GP will look at the mole and other areas of skin and may ask to take a photograph to send to a dermatologist, called teledermatology.

The NHS says moles only need treating if they are a sign of melanoma. If the GP thinks it may be melanoma, you will be referred to a specialist in hospital and should get an appointment within 2 weeks. An urgent referral does not definitely mean you have cancer. The main treatment for melanoma is surgery to remove the mole.

Harmless moles are not usually treated on the NHS. You can pay a private clinic to remove a mole, but the NHS notes it may be expensive.

UV light from the sun can increase the chance of a mole becoming cancerous, and the NHS says that if you have lots of moles you need to be extra careful in the sun. It advises staying in the shade between 11am and 3pm when sunlight is strongest, covering skin with clothes, wearing a hat and sunglasses if you have moles on the face, regularly applying a high-factor sunscreen (minimum SPF30) and reapplying after swimming, and not using sunlamps or sunbeds.