Key takeaways
- Most cases of skin cancer are caused by too much ultraviolet (UV) radiation from the sun and sunbeds
- You have a higher risk of skin cancer if you have white skin, are older, have been sunburnt in the past and if you use sunbeds
- Melanoma is the most serious form of skin cancer, and is most treatable when caught early
- Checking for new or different moles every month can help you catch melanoma early
Too much sun exposure can cause skin cancer by damaging the DNA in our cells. Melanoma is the most serious type of skin cancer, and survival rates are limited if it goes untreated. If you are over 50 or at risk of skin cancer, it’s important to check your skin for new and changing moles, at least monthly. In this article, Perci’s lead cancer nurse specialist Rachel Rawson explains the link between the sun and cancer risk, takes you step-by-step through a mole-checking technique, and introduces mole mapping.
What causes skin cancer?
The majority of skin cancers are caused by too much UV radiation from the sun and sunbeds. UVA and UVB are the two main types of sun rays, and both cause skin cancer by damaging the DNA in your skin cells.
What is melanoma?
Melanoma is the most serious type of skin cancer and is the 5th most common cancer in the UK, accounting for 4% of all new cancer cases. When melanoma is found and removed in its early stages, more than 90% of people will survive long term. However, if the melanoma has already reached an advanced stage it is less easy to treat and fewer people will survive.
What is non-melanoma skin cancer?
Non-melanoma skin cancer is a common type of cancer that starts in the top layer of skin. The main types are basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). Non-melanoma skin cancer can often be easily treated.
The main risk factors for non-melanoma skin cancer are age, a history of sunburn and sunbed use. White people have a higher risk of skin cancer.
Age:
The older you are, the more likely you are to develop non-melanoma skin cancer. But skin cancers can develop in younger people too.
History of sunburn:
This increases your risk of skin cancer. The risk is especially high if you were sunburnt several times during your childhood. People who work outside such as farm workers, gardeners and building site workers are also at an increased risk of non-melanoma skin cancer.
White skin:
Skin cancer is more common in people with white skin. This is because they have less of the protective pigment called melanin. People with black skin are less likely to get skin cancer but are still at risk.
Sunbeds:
These produce ultraviolet light which damages the skin. Research has shown that using a sunbed causes melanoma. There is now evidence to say that sunbeds might also increase the risk of non-melanoma skin cancer.
What to do if you’re concerned
Checking your skin on a monthly basis will help you to notice if there are any changes to existing moles, freckles or a previously normal patch of skin. The earlier a melanoma is found, the easier it is to treat, so it’s important to see your GP as soon as possible if you notice a change.
What are you looking for when you check for moles?
When checking your skin for moles, you are looking for moles that are asymmetric (the two halves won’t match), that have irregular borders, many colours and a diameter bigger than 6mm (bigger than a pencil). Remember this with the ABCD rule:
Asymmetric
Borders
Colours
Diameter (as well as ‘different’ and ‘dark’)
It’s also helpful to remember the ‘ugly duckling sign’, which refers to a mole that looks different to those around it. An ugly duckling may be a single large dark mole in amongst a sea of smaller lighter moles, or it could be a single small light mole in amongst a sea of large dark moles. The point is that it’s different from the rest.
The letters E, F and G are used to help you detect ‘nodular melanomas’. These different types of melanomas are typically:
Elevated
Firm and
Growing
How to check your skin for moles
With a little practice you can check your whole body for moles. Look methodically, zone by zone, in the following nine steps. You’ll need a full-length mirror and a hand mirror.
- General scan: first, simply look at your skin in the mirror.
- Hands: Look at them back and front.
- Arms: Raise the arms to look under armpits and at the backs of the arms, then drop them. Twist arms inwards and then outwards, looking at all of the skin.
- Upper body: Look across neck, upper shoulders, chest and tummy
- Legs: Look at upper legs, areas around knees, lower legs and then feet, including the soles of the feet and spaces between toes.
- Back: Turn your back to the mirror slightly and look over your shoulder at the upper, middle and lower back, and the backs of the legs.
- Face: Stand close to the mirror and look at the upper face and forehead, pulling the hair back, followed by the middle of the face from cheek to cheek, then the lower face, including jawline, lower mouth and lips
- Ears: Place a handheld mirror behind your ear, folding the ear back to look at the upper, middle and lower areas.
- Head: Still using the mirror, look at the top of the head, parting the hair systematically to look at all areas of the scalp. Run your hand through your scalp to feel for new lumps.
A partner or friend can help check areas that are difficult to see on your own, including the back, scalp and feet. This resource is also helpful, and you can print and record what you find.
What is digital mole-mapping?
Digital mole mapping is a safe, non-invasive screening service that may be offered to patients at risk of, or concerned about skin cancer. It uses a specialist digital photo documentation system to map the moles on a person’s entire body. The photographs produced can then be compared, to identify changing or new moles over time, and detect melanoma at an early stage when treatment is most effective. If you have any concerns, speak to your GP about mole mapping.
Perci’s Cancer Nurse Specialists are available if you want to discuss your risk of skin cancer, and can help you make a plan to stay safe in the sun.
While we have ensured that every article is medically reviewed and approved, information presented here is not intended to be a substitute for professional medical advice, diagnosis, or treatment. If you have any questions or concerns, please talk to one of our healthcare professionals or your primary healthcare team.
References:
‘Check your skin today,’ DermNet, July 2021, https://dermnetnz.org/topics/check-your-skin-today
‘Digital mole mapping,’ University Hospital Southampton, april 2023, https://www.uhs.nhs.uk/Media/UHS-website-2019/Patientinformation/Skin/Digital-mole-mapping-2938-PIL.pdf