Many people will be looking forward to spending more time outdoors as summer beckons, so it is a good time to brush up on sun safety and minimising the risks of skin cancer
After reading this feature you should be able to:
• Reinforce sun protection measures and the role of vitamin D
• Explain about self-examination and the ABCDE checklist
• Identify those patients receiving photo- sensitising drugs (e.g. amiodarone; doxycycline) to ensure they are aware of the risks of rapid burning.
The major preventable cause of skin cancers is excessive sun exposure. Some people are at higher risk of developing skin cancers and deserve special attention. These include:
When the UV index is 3 or more, there is enough UV radiation to damage skin and sun protection measures are required. A number of apps that provide the UV index are available for smart phones.
The general advice should always be to avoid unnecessary exposure to intense UV light (i.e. between 11am and 3pm). This can mean staying in shade or covering up with a wide-brimmed hat, sunglasses and loose clothing or UV-protective swimwear. Sunbeds should be avoided at all times.
A broad spectrum sunscreen with a sun protection factor (SPF) of at least 30 (for UVB) and a star rating of 4-5 (for UVA) should be used. Sunscreens should be applied generously and reapplied every two hours if washed, rubbed or sweated off. “Not using sunscreen properly puts people at risk of developing skin cancer. Eighty to 90 per cent of all skin cancers occur on the face and neck,” says Dr Sonia Khorana, a GP with a special interest in dermatology.
Organ transplant recipients should use a high-factor (SPF 50) sunscreen on all exposed skin, including the lips, when outdoors. This is because they have a 10- to 250-fold higher risk of developing skin cancer (usually squamous cell carcinomas).
• Excessive exposure to ultraviolet (UV) light is linked to skin cancers of all types
• There are more than 16,000 new cases of malignant melanoma each year and more than 2,000 deaths; 86 per cent of malignant melanomas are preventable1
• Non-melanoma skin cancers – basal cell carcinomas (BCCs) and squamous cell carcinomas (SCCs) – account for about 90 per cent of skin cancers
While protecting the skin from unnecessary UV exposure, it is important not to overlook vitamin D requirements. Vitamin D is made in the skin by the action of sunlight (UVB) on cholesterol. From October to April there is insufficient sunlight for this to occur in the UK and vitamin D deficiency is common.
It is now known that vitamin D is not only important for bone and muscle function but also for proper functioning of the immune system. Vitamin D doses of 800-4000IU/day (depending on circumstances and needs) are recommended.2
In the context of melanoma, vitamin D deficiency is associated with poorer outcomes, while higher levels of vitamin D in the blood are linked to smaller tumours and better outcomes.3
Melanoma diagnoses fell 28 per cent from April to November 2020 during the Covid-19 pandemic compared to the previous year, which equates to an estimated 2,671 fewer diagnoses than expected.
It is thought that the drop in skin cancer cases is due to a reduced number of people seeing their GP about potential skin cancers during the pandemic. May saw the steepest drop-off in melanoma diagnoses, with just 54 per cent of the expected number of diagnoses for the month.
Estimates suggest that there were even larger drops in the number of keratinocyte cancers diagnosed. The number of BCCs and SCCs biopsied in April 2020 was just 22 and 58 per cent of the number biopsied in April 2019.
“We are becoming increasingly aware that the Covid-19 pandemic has effects far beyond those immediately infected by the virus," says Dr Zoe Venables, dermatology consultant at the Norfolk and Norwich University Hospital and dermatology clinical lead, National Cancer Registration and Analysis Service.
"Fewer cancer diagnoses are being made during the pandemic and it is of grave concern that this represents patients who are likely to present later, resulting in worse outcomes. We strongly encourage the public to do routine body checks including a full body skin check and attend their GP practice should they have any concerns.”
Early treatment of skin cancers – especially melanomas – is important. Routine self-examination of the skin should be encouraged, especially for people in the high-risk groups.
Skin should be examined from head to toe each month to check for changes and a dermatologist should be seen for a full-body skin examination at least once a year. The ABCDE checklist is recommended for identifying suspected melanomas:
Advanced melanomas, where disease has spread to the lymph nodes and beyond, cannot be treated by simple removal of the skin lesion. In recent years, the use of adjuvant immunotherapy using checkpoint inhibitors and targeted therapy (for those with BRAF mutations) has improved the outlook for patients.
Recently neo-adjuvant therapy using checkpoint inhibitors or targeted therapy was hailed as a breakthrough because it further reduced the risk of recurrence after surgery.4 Adjuvant therapy is given after surgery and neo-adjuvant therapy before surgery.
A recent study investigated the impact of consuming whole grape powder – equivalent to 2.25 cups of grapes per day – for 14 days against photodamage from UV light.5
Following grape consumption, more UV exposure was required to cause sunburn – the minimal erythema dose (MED) increased by 74.8 per cent on average, showing that grape consumption was protective.
“We saw a significant photo-protective effect and were able to identify molecular pathways by which that benefit occurs – through repair of DNA damage and down-regulation of pro-inflammatory pathways,” said Dr Craig Elmets, the principal investigator.
“Grapes may act as an edible sunscreen, offering an additional layer of protection in addition to topical sunscreen products.”