Ask the Expert: Mr Per Hall answers some of the most commonly asked questions around skin cancer and shares his insights on how to minimise your risk

Mr Per Hall, skin cancer Clinical Advisor for Skin Cancer at Check4Cancer and Consultant Plastic Surgeon, answers some of the most commonly asked questions around skin cancer and shares his insights on how to minimise your risk.

Who is most at risk of skin cancer and what are the risk factors?

Ultraviolet exposure is generally the biggest single risk factor, but some individuals may be at a greater personal risk, such as those with a family history of skin cancer. Those with a very large number of moles also have a much higher risk compared with the general population. Congenital moles (moles people are born with) are also more likely to become cancerous, particularly if they are very large, which will impact an individual’s risk.

Skin type also impacts the risk of getting skin cancer. Skin that tends to burn or freckle rather than tan, referred to as Skin Type 1 (Fitzpatrick Skin Type 1 or Celtic skin), increases skin cancer risk. Those who have been brought up in hot sunny climates particularly with skin types 1-3 (Fitzpatrick Skin Type Scale) are also more prone to developing skin cancers.

Fitzpatrick Skin Types

Risk factors for skin cancer include:

  • Previous history of a skin cancer
  • A family history of melanoma
  • A large number of moles (10 times risk if >100 moles)
  • Abnormal or irregular (dysplastic) moles
  • Born with a congenital mole
  • Freckles
  • Skin that tends to burn rather than go brown (Fitzpatrick Skin Type I)
  • A history of blistered sunburn
  • Excessive ultraviolet exposure
  • Living in a hot, sunny climate
  • Living close to the equator
  • Going on sunny holidays
  • Use of sunbeds
  • Lowered immune system

Is there a way to assess individual risk?

Check4Cancer uses a risk assessment score to help decide who should have regular skin checks. This involves a number of questions based on research by Williams et al.1

These questions take into account individual features which increase skin cancer risk e.g. mole count, freckling, hair colour, history of blistering sunburn, and personal history. Using this system, we can identify those more at risk of melanoma: a score of 28 or more is in the top 15% of the country which accounts for 50% of all melanomas. These people are therefore at the greatest risk of melanoma, and worth keeping a closer eye on.

How can you minimise your risk of skin cancer?

It is important to be vigilant and take care in the sunshine, particularly if you have fair skin (Fitzpatrick Skin Types 1 and 2). Avoid the mid-day sun, cover up where you can with clothing and use a high factor sun cream (SPF 30 or higher, minimum 4-star UVA protection2). It is also important to prevent children from getting sunburn.

What symptoms should you look out for?

Any new lesion on the skin or lesion that has changed in size, shape or colour should be examined to make sure it is benign. A lesion means any abnormal changes in the skin – any altered skin colour, new marks or changes in skin texture could be called a lesion. Risks are greater with advancing age, but some melanomas appear in relatively young people in their 20s and 30s.

Can you check yourself at home? What changes should you look out for on your moles?

You can keep an eye out for any new lesions or changes to existing moles yourself. It is worth getting someone to take some good quality pictures in natural light to check against in the future. Comparing pictures side-by-side is a good way of spotting any changes.

Checking your Skin PNG 


What should you do if you notice something unusual?

If you do notice a change in a lesion it is important to get it checked as soon as possible by your GP or a skin cancer specialist.

Can you get screening on the NHS?

Your GP can refer you to your local hospital (under the 2-week wait pathway) if they are concerned that your lesion might be melanoma. There are other skin cancers such as Squamous Cell Carcinoma which most NHS facilities try to see within 4 weeks of referral and Basal Cell Carcinomas, which are very slow-growing lesions, that are seen in a more routine fashion.

What screening does Check4Cancer offer?

SkinCheck, provided by Check4Cancer, is a fast-track skin cancer screening service for anyone who wants a specialist clinical opinion on the appearance of their skin or moles. SkinCheck helps separate out lesions that have friendly appearances from those that may be a cause for concern.

How often would you recommend having your skin checked?

It is a good idea to check your own skin every 1-2 months - set a reminder up in your diary. For those at a greater risk of developing skin cancers (described above), it is a good idea to have a formal skin check on a yearly basis.  

Why is regular screening and early detection so important?

The earlier skin cancer is detected, the better the outcome. This is particularly true for a malignant mole or melanoma. If a melanoma can be detected when it has only just started to change and is still only in the top layers of the skin then the outlook can be very good, with 97% of thin early melanomas resulting in no more problems over the next 5 years.

But, if the melanoma is diagnosed late and has grown into the deeper part of the skin, the chances of the cancer spreading to either the lymph glands or other parts of the body are greatly increased. There is then a consequent increase in the overall rate of recurrence and drop off in long term survival. 

Our eyes are the key to recognising when something is abnormal as there are no other useful tests to check for skin cancers.



1 Williams LH, Shors AR, Barlow WE, Solomon C, White E. Identifying Persons at Highest Risk of Melanoma Using Self-Assessed Risk Factors. J Clin Exp Dermatol Res. 2011;2(6):1000129. doi:10.4172/2155-9554.1000129



Mr Per Hall | Clinical Advisor for Skin Cancer at Check4Canncer 

Mr Per Hall has been a consultant plastic surgeon in Cambridge since 1995. He has been a pioneer in the early detection of skin cancer using computer imaging for over 20 years. Mr Hall and his team have had a major input in the development of SIAscopy, producing the most clinical papers on the subject. He continues to collaborate in studies aiming to help identify suspicious skin lesions at the earliest opportunity and continues to work with computer scientists on ways to improve diagnosis including the use of artificial intelligence. Mr Hall is also committed to the reconstructive surgical needs of children in developing countries and regularly trains surgeons in cleft lip and palate surgery in Ethiopia to facilitate this. Mr Hall oversees the Check4Cancer SkinCheck service.