After a hot summer when people spent more time outdoors than usual because of lockdown, it is time to assess the damage caused by over-exposure to sunshine, writes Steve Titmarsh... 
 

While it has definite benefits, too much exposure to the sun can result in skin damage, with associated health implications. UV radiation is responsible for a lot of the damage done to our skin – from wrinkles to discoloration and cancer. 

For most of the conditions discussed here, reducing sun exposure can help prevent or at least lessen their impact, so sunscreens are advisable year-round. 

In some individuals sun exposure can cause a variable increase in melanin resulting in an uneven skin tone.1 This can manifest as freckles, age spots or melasma, for example. Age spots (solar lentigines) are usually seen on the face, forearms and the back of hands. They appear in middle age as flat, evenly brown coloured and can be quite large.2 Unlike age spots, freckles can fade during the winter and are usually less than 3mm wide.3  

Actinic (solar) keratosis are scaly spots that develop as a result of UVB damage to the skin. They are most commonly seen on the face and backs of hands. They are also seen on the upper body, arms and legs as well as the tops of the feet. They can appear singly or in groups, appearing as:4

- a flat or thickened papule or plaque

- white or yellow; scaly, warty or horny surface

- skin coloured, red or pigmented. 

They can be tender or asymptomatic. They should be checked by a GP when noticed for the first time.4 Cream containing diclofenac, 5-fluorouracil, salicylic acid or imiquimod may be prescribed. If they are unsightly or uncomfortable they are usually removed.5  
Wrinkles are a feature of ageing skin and can result from sun exposure, although genetics and other environmental factors also play their part.

Moisturisers, used regularly, can help as can using non-soap skin cleansers. Some cosmetics claim to be anti-ageing: they contain ingredients such as topical retinoids, vitamin C, alpha hydroxy acids, polypeptides and various plant extracts. Topical retinoids are regarded as having the best evidence of effect.5

As a more radical solution, chemical peels can even out skin pigmentation and texture.5  

Too much melanin? 
Melasma is caused by over-production of melanin. Also known as chloasma, it commonly affects adult women. Characteristic features consist of flat, brown or greyish patches of bilateral hyperpigmentation on the face, typically occurring on the forehead, cheeks, nose and upper lips.6,7,8 Oral contraceptives, hormone replacement therapy and UV radiation exposure are thought to be risk factors.7 

Diagnosis is based on appearance, with treatment focussing mainly on improving appearance as there is no cure. As well as avoiding known triggers, treatments include azelaic acid cream (15–20 per cent) as a monotherapy or in combination with a topical retinoid.9 The Primary Care Dermatology Society (PCDS) also recommend oral tranexamic acid.8,10  

Dermatologists may offer chemical peels containing glycolic acid or trichloroacetic acid. Skin lightening creams containing hydroquinone 2–4 per cent prevent melanin production by inhibiting conversion of dopa in the skin. Skin irritation is a potential side-effect of hydroquinone creams.7,11

Retinoid and steroid creams have similar effects. Cosmetics are also promoted to conceal the appearance of melasma. Avoiding or reducing sun exposure and using sunscreen with a high SPF remains the mainstay of self-care advice.  

Skin cancers 
There are two main types of skin cancer: melanoma and non-melanoma. 

Melanoma is the fifth most common cancer in the UK, usually appearing in or near a mole and most often on the trunk or legs.12,13,14 Features include minor changes in size, shape or colour of the mole, itchiness or tingling, or the appearance of a dark area on the skin. People who burn easily or tan poorly are at a higher risk.15 Regular use of a sunbed use also increases susceptibility.  

Surgical removal is the main treatment. Almost 9 out of 10 people diagnosed with melanoma survive for 10 years or more.13 Therefore, the ABCDE system of monthly self-surveillance is important to detect lesions at an earlier stage for diagnosis and treatment.15 This involves looking for:

• Asymmetry to check if the two halves of the area are different in shape 
• Border edges of the area may be irregular, blurred and show notches 
• Colour may be uneven - different shades of black, brown and pink may be seen 
• Diameter, as most melanomas are at least 6mm in size and keep growing 
• Evolution to monitor rapid changes in a pre-existing mole. 

Customers should be encouraged to regularly check moles, spots, dark and/or scaly patches: any of these changes should prompt medical referral for further investigation. 

Long-term skin care involves reducing sun exposure, use of high protection SPF30 or more and monitoring of changes in skin appearance. Awareness of the Miiskin app16 should be shared with customers to help them monitor changes in skin moles and detect the appearance of new ones.  

Basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) are categorised as non-melanoma skin cancers (NMSC). UK data for 2015–17 show that 410 new cases were diagnosed each day with almost half (47 per cent) occurring in people aged 75 years and older.14  

BCC is the most common type of skin cancer and it is mostly found on the face ears and neck. Common risk factors include age, pale skin, long-term exposure, intensity of the sun, regular use of sunbeds and skin burning.  

People often present with a scab that bleeds or does not heal completely or a new lump on the skin. Visual appearance may include a scaly, red flat mark, others may have a pearl-like rim around a central crater. As these are slow-growing tumours and highly curable, prompt medical referral is essential.9,14  

SCC is the second most common type of NMSC. It usually occurs on exposed areas like the scalp, ears, neck and back of the hands. The visual appearance of SCC is variable with people noting a spot or sore that has not healed for four weeks or more, or they may notice spots that have become itchy, crusty, bleed and/or scab over. Skin ulceration may occur.9,13

In addition to the risk factors previously mentioned, people with immunosuppression, albinism and xeroderma pigmentosum are at a higher risk of developing SCC. 

Surgery is the most common treatment to excise the BCC or SCC.9 Radiotherapy is an alternative treatment if surgery is not suitable.9,17,18  

Additional reporting by Kumud Titmarsh. 

References

1. Primary Care Dermatology Society. Lentigo www.pcds.org.uk/clinical-guidance/lentigo (accessed November 2020).

2. DermNet NZ. Brown spots and freckles https://dermnetnz.org/topics/brown-spots-and-freckles (accessed November 2020).

3. DermNet NZ. Actinic keratosis https://dermnetnz.org/topics/actinic-keratosis (accessed November 2020).

4. NHS.uk Actinic keratoses (solar keratoses) www.nhs.uk/conditions/actinic-keratoses (accessed November 2020).

5. DermNet NZ. Facial lines and wrinkles https://dermnetnz.org/topics/facial-lines-and-wrinkles (accessed November 2020).

6. Mayo Clinic. Sun damage www.mayoclinic.org/healthy-lifestyle/adult-health/multimedia/sun-damage/sls-20076973 (accessed November 2020).

7. British Association of Dermatologists. Melasma www.skinhealthinfo.org.uk/condition/melasma (accessed November 2020).

8. Primary Care Dermatology Society. Melasma chloasma www.pcds.org.uk/clinical-guidance/melasma-syn.-chloasma1 (accessed November 2020).

9. British Association of Dermatologists. Melasma www.bad.org.uk/shared/get-file.ashx?id=169&itemtype=document (accessed November 2020).

10. Ali FR. Oral tranexamic acid for the treatment of melasma. Clinical and Experimental Dermatology https://onlinelibrary.wiley.com/doi/10.1111/ced.13831 (accessed November 2020).

11. Harding M, Huins H. Melasma (chloasma) https://patient.info/doctor/melasma-chloasma-pro#nav-1 (accessed November 2020).

12. British Skin Foundation. www.britishskinfoundation.org.uk/what-is-skin-cancer (accessed November 2020).

13. Cancerresearch UK. Melanoma skin cancer incidence www.cancerresearchuk.org/health-professional/cancer-statistics/statistics-by-cancer-type/melanoma-skin-cancer#heading-Zero (accessed November 2020).

14. Cancerresearch UK. Non melanoma skin cancer incidence statistics www.cancerresearchuk.org/health-professional/cancer-statistics/statistics-by-cancer-type/non-melanoma-skin-cancer/incidence (accessed November 2020).

15. British Association of Dermatologists. Melanoma in situ www.skinhealthinfo.org.uk/condition/melanoma-in-situ (accessed November 2020).

16. Miiskin app https://miiskin.com/ (accessed November 2020).

17. National Institute for Health and Care Excellence (NICE). Improving Outcomes for people with skin tumours including melanoma. London: NICE, 2006.

18. National Institute for Health and Care Excellence (NICE). Improving Outcomes for people with skin tumours including melanoma (update). London: NICE, 2010.