Skin cancer is almost always caused by damage sustained by skin cells due to excessive ultraviolet (UV) exposure. This process takes place over many years. I use a piggy bank as metaphor when I explain UV exposure to patients:

Every time in your life – from the day you were born, essentially - that you are exposed to UV rays, you deposit UV damage into your piggy bank. This accumulates over time, and at some stage (for some unfortunate patients as early as 16) you earn interest on the savings in the form of wrinkles, hyperpigmentation and DNA damage to your skin cells that multiply as cancerous cells, rather than benign skin cells. But this is a piggy bank with a difference – even if you take out all the money (i.e. stay out of the sun and wear extensive UV protection), you continue to earn interest on the initial deposits you made – so the damaging effects continue for the rest of your life.  

The skin cancer you suffer from today is the result of over-exposure to UV rays when you were young. It is for this reason that people like air force pilots and avid sportsmen are often riddled with skin cancers as they grow older.  Just one excessive UV exposure in a lifetime could result in a skin cancer.

Medical grade sun protection, with a minimum of an SPF50, will not only help to prevent skin ageing, but also plays a crucial role in preventing skin cancer.

Excess UV exposure is not the only cause of skin cancer, however, and many industrial compounds can cause skin cancer. Genetic factors also play a role, and although patients with darker skins are less likely to get skin cancer, because they have more of the pigment melanin that protects us against skin cancer, they are not excluded from it – the famous reggae star Bob Marley died from malignant melanoma, for instance.  

As with any cancer, early detection is essential – not only does this mean that the cancer can be removed less invasively, it also means less scarring, and a lower risk of spreading to other areas.

If you have had some, or a lot of sun exposure in your life, you should visit a dermatologist for a full body examination. If you have a lot of moles, mole mapping is an excellent way in which to document your moles. In this way, over time, one could determine whether they progress towards something more sinister.  

Self-examination and examination by a life partner for areas like the back, scalp and buttocks are important. It is also important to look in the ear, behind the ear, and between your toes and under your feet (Bob Marley’s malignant melanoma was on the sole of his foot). The ABC’s of skin cancer are useful: look for Asymmetrical lesions, with irregular Borders, different Colors in the same lesion, with a Diameter of more than the back of a pencil, or which have increased in size.  

Non-healing areas anywhere on the body or areas that bleed every now and then, or peel continuously or are ulcerating, are all potential skin cancers – if your body has not healed a little wound in 30 days, please have it seen to. A chronic ulcer must have an origin or reason for being there – and often, it is skin cancer that has been ignored.

If you are unsure whether a lesion is cancerous or not, contact your dermatologist or general practitioner first. They are best equipped to evaluate and conservatively treat potential skin cancers, or to perform a biopsy to determine if a lesion is cancerous or not.  If, after an attempt to treat the lesion conservatively, the lesion re-occurs, it is best to perform a biopsy, or to do a formal excision.

Patients offer many reasons why they don’t use sun protection – from cosmetic reasons (make up does not stay on, skin looks oily etc.), to functional reasons (the sunblock runs into my eyes), or they fear developing a Vitamin D deficiency.  Other patients don’t use sun protection, because they are “never” in the sun.

Incidental sun damage is inevitable in South Africa: hanging up washing outside, sitting in the garden for a braai, chatting to friends in the parking lot at school or at the shopping mall, driving in your car – you are continuously exposed to the sun, and ten minutes’ unprotected exposure is enough to cause DNA damage. Artificial lights, computer screens, tablets and cell phones also radiate skin cancer-inducing rays.

The alternative to non-protection with an SPF50 is coping with a scar where the skin cancer was removed, or wrinkles.