Solar Keratoses

Our skin is our largest organ. It is our first line of defence against damaging sunlight, unsafe chemicals, extreme temperatures, harmful bacteria and other bugs we encounter every minute of every day. Each Australian adult has an average 3.6 kilograms and two square metres of skin, yet recent research reveals most Australians don’t even know that their skin is an organ.1

Many people over the age of 40 lived in the pre‐SLIP SLOP SLAP era, enjoying time in the strong Australian sunshine with minimal protection without being aware of the dangers. Despite Australia’s harsh climate and very high life‐time prevalence of sun burn, over one third of Australian’s aged 40+ believe they are not at risk of sun damage because they avoid the sun and use sun protection.1 In fact, everyone is at risk.

Two in three Australians will be diagnosed with a form of non‐melanoma skin cancer before the age of 70.2 Yet despite this, only three in ten Australians 40+ get annual skin checks.1 It seems many don’t know how important a role their skin plays in keeping their bodies healthy and looking well. However, warning signs can precede the development of skin cancers and in particular the development of squamous cell carcinoma. The presence of solar keratoses on the skin is often considered to be a potential precursor for the development of this form of cancer.

Solar (actinic) keratoses, sometimes referred to as sun spots, is an early stage in the development of invasive squamous cell carcinoma (SCC). SKs appear as a result of prolonged and repeated sun exposure. The typical solar keratoses lesion is a dry, scaly, skin-coloured, reddish-brown or yellowish-black lesion. The onset of solar keratoses is subtle and therefore often passes unnoticed for some time before diagnosis. Solar keratoses lesions are usually found on chronically sun-exposed sites of the head and neck and the dorsum of the hands and forearms.

Due to the fact that solar keratoses occurs as multiple lesions instead of just single lesions the development of the term 'field cancerisation' has been employed. Therefore, many clinicians believe that treatment should be applied to a field of solar keratoses in order to treat the complete area including the sub clinical lesions.

Non visible, non-palpable lesions (sub-clinical lesions) are estimated to occur up to 10 times more often than visible solar keratoses lesions. If left untreated, solar keratoses can progress into thickened lesions and subsequently may develop into invasive SCC. SCC is the second leading cause of skin cancer deaths in the US. Many patients who have an solar keratoses lesion will often have multiple lesions and further lesions may become clinically evident in the future. However, as always, prevention is better than cure. Therefore it is recommended that all Australians should check their skin regularly. Indeed learn techniques to ensure that they are able to detect changes to their skin and hence seek professional advice before any changes develop into more serious problems.

Know Your Own Skin (KYOS) is a health campaign designed to do just that – help Australians get to know their own skin. The campaign will provide Australians with useful information, advice and tools to help them better understand and take care of their own skin, in order to monitor sun damage and seek medical treatment as appropriate.


  1. Kantar Health 2010. Australians over 40 and their skin. 
  2. Staples M et al. Non‐melanoma skin cancer in Australia: the 2002 national survey and trends since 1985. Medical Journal of Australia 2006; 184: 6‐10.