STEP 1: Prevention and early detection
This step outlines recommendations for the prevention and early detection of keratinocyte cancer.
Evidence shows that not smoking, avoiding or limiting alcohol intake, eating a healthy diet, maintaining a healthy body weight, being physically active, being sun smart and avoiding exposure to oncoviruses or carcinogens may help reduce cancer risk (Cancer Council Australia 2018).
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).
The risk factors for developing keratinocyte cancer include the following.
Environmental and exogenous risk factors:
- chronic sun exposure
- multiple solar keratoses
- solarium use
- intensive UV exposure in childhood and adolescence – this is a stronger causative factor for developing BCC, whereas SCC is associated with chronic sun exposure over decades (Leiter & Garbe 2008); sun exposure in adulthood, however, is an important risk factor for both SCC and BCC (Iannacone et al. 2012).
- past exposure to arsenic.
Personal risk factors:
- some rare genetic conditions predisposing to skin cancer
- skin types I and II (these have a higher risk of sunburn)
- a history of blistering sunburn
- increasing age
- a previous diagnosis of melanoma or BCC/SCC (up to 60 per cent grow another within three years)
- solar keratoses.
Lifestyle risk factors:
- outdoor occupations
- recreational sun exposure.
Medical risk factors
- UVA and psoralen (PUVA) treatment for psoriasis
- immunosuppression (e.g. post transplantation, chronic lymphomas and leukaemias)
- previous radiotherapy
- some photosensitising medications (e.g. methotrexate and voriconazole).
There is no evidence that population-based screening for keratinocyte cancer is effective in reducing morbidity or mortality, and it is not recommended.
The patient’s first point of contact for detecting keratinocyte cancer early should be their general practitioner.
Management of all patients should include:
- education about skin awareness and encouragement of regular self-examination
- education about skin cancer prevention for the person at risk and their family
- education about average, increased and high-risk patient factors.
For most patients, screening is opportunistic, unless patients are in a high-risk category, whereby six to 12-monthly reviews with an adequately trained and experienced clinician is warranted. High-risk patients include those with:
- a history of keratinocyte cancer – up to 60 per cent of patients will develop another primary keratinocyte cancer within three years
- a previous melanoma
- immunosuppression (e.g. post-transplant)
- certain genetic syndromes (e.g. Gorlin’s syndrome)
- past exposure to arsenic.
Total body skin examination of patients should be practised by a practitioner with adequate training and experience (Cancer Council Australia Keratinocyte Cancers Guideline Working Party 2019). An agreed scope of practice in keratinocyte cancers (SCCs/BCCs) is required of practitioners undertaking screening or treatment of these cancers.
Skin cancer clinics are accessible without a Medicare Benefits Schedule (MBS) referral in Australia, and are generally staffed by general practitioners with a special interest in skin cancers. Documented evidence of the practitioner’s further experience and training in skin cancers should be available.
Refer to The Red Book for further primary care specific information.
