Recommendations for preventing keratinocyte cancer:

Solar radiation is the major environmental cause of all skin cancers. The current policy for daily sunscreen use is: people living in Australia should apply sunscreen to the face/head/neck and all parts of the body not covered by clothing on all days when the ultraviolet (UV) index is forecast to reach 3 or higher, irrespective of their anticipated activities (Whiteman et al. 2019). Attention must be given to occupational and incidental sun exposure, in addition to recreational sun exposure.

Effective strategies for skin cancer prevention (to be used during sun protection times when the UV index is 3 or above) include:

• wearing long-sleeved clothing
• wearing a broad-brimmed hat
• applying a broad-spectrum sunscreen with a SPF of 30 or higher
• wearing sunglasses
• seeking shade
• avoiding getting sunburnt, especially to the point of blistering and skin peeling because multiple episodes have been shown to increase the risk of developing keratinocyte cancer
• protecting children from sunburn and long-term overexposure to the sun – this reduces their risk of developing skin cancer later in life
• not using solariums
• stopping smoking – epidemiological studies consistently report higher rates of SCC among current smokers but not former smokers; no consistent trends with duration or dosage of smoking were found (Dusingize et al. 2017).

People should be encouraged to use a combination of sun protection measures during sun protection times to avoid relying on one form of sun protection, and as an adjunct to minimising UV exposure. People should also be encouraged to download the free SunSmart app.

‘Nicotinamide may be a useful chemo-preventive adjunct to sun protection and sunscreen use in high risk, immune-competent individuals with a history of multiple keratinocyte cancers. It should not be recommended for lower-risk individuals without a history of skin cancer’ (Cancer Council Australia Keratinocyte Cancers Guideline Working Party 2019).