Skin cancer can be divided into two main groups:
Malignant melanoma and
Non-melanoma skin cancer.
Malignant melanoma is the rarest, but most serious form. It affects the pigment-producing cells (melanocytes) found in the skin and can appear as a new mole, or arise from an existing mole on the skin. Malignant melanoma has the potential to spread to other sites or organs within the body but is curable if treated early. Each year about 235 females and 150 males are diagnosed with malignant melanoma in Ireland.
Non-melanoma skin cancers (Basal cell carcinoma and squamous cell carcinoma)
Non-melanoma skin cancers are far more common but less dangerous than malignant melanoma and rarely fatal. Basal cell carcinoma and squamous cell carcinoma frequently appear on sun-exposed skin after many years of exposure. This exposure also causes premature ageing of the skin. Non-malignant skin cancers are easily treated by minor surgery. If left, non-melanoma skin cancers will grow and disfigure – therefore early treatment is recommended. Each year about 7,500 people are diagnosed with non-melanomatous skin cancers in Ireland with 3445 in females, 3889 in males.
Basal cell carcinomas
Squamous cell carcinomas
Solar keratoses (actinic)
Solar keratoses develop on skin which has been damaged by long term sun exposure. Usually many are present and can appear as hard, scaly lumps. Some become unsightly as they slowly grow larger. The skin underneath solar keratoses can vary in colour from a normal fleshy shade to pink or red. Sometimes these skin lesions can become itchy. Common sites are the face, backs of hands, forearms, ears, scalp and neck. Solar keratoses are not skin cancers. However, a very small percentage can develop into a skin cancer in later life. Some specialists regard solar keratoses as precursors to skin cancer, therefore it is important to seek medical advice on treatment.
– Solar keratoses appear as hard scaly lumps on the skin. They may crust but do not heal.
– Solar keratoses can be rough, scaly irregular patches which are easily felt but not clearly seen.
– Often they are not troublesome in anyway but do not heal.
– Some are very troublesome, if present on the lips or nose as they tend to bleed spontaneously.
Solar keratoses are most frequently treated by freezing using Liquid Nitrogen (Cryotherapy) or by applying a treatment cream. Some larger lesions may be removed by minor surgery under local anaesthesia. Treatment is usually carried out on an out-patient basis with the minimum disruption to your daily routine. All treatments aim to cure. The most appropriate treatment depends on the size, site and number of solar keratoses. Solar keratoses seldom recur following treatment but others may develop over the years.
Who is most at risk of developing skin cancer?.
People with very fair skin are most at risk of developing skin cancer. Those who cannot develop a tan are most at risk of malignant melanoma, but everyone is at risk of being sunburnt, especially indoor employees, children and babies. Malignant melanoma is more common in females. Non-melanoma skin cancers are most frequently seen in older age groups and outdoor workers who have a continuous all-year tan. The incidence of skin cancer is rapidly rising in the young adult population.
Are skin cancers treatable?
Both malignant melanoma and non-melanoma skin cancers are curable if treated in the early stages. A minor surgical procedure is all that is usually required to remove cancers of the skin. Regular inspection of skin and moles at home helps in recognising any abnormal skin lesions or changing moles. Change in size, shape and colour of a mole are the early warning signs of malignant melanoma, the most dangerous form of these skin cancer, because it can quickly metastasise to other parts of the body. However, if is detected soon after if first develops, it is curable by simple surgical excision. In Ireland, over 375 cases of melanoma are reported each year and up to 60 Irish people will die of this disease.
The most common form of skin cancer in Ireland is basal cell carcinoma BCC, of which over 3,500 new cases are reported each year. These numbers are almost halfed between male and female and the incidence shows a small increase over the past six years. This cancer very rarely spreads to other organs but if left undetected, will continue to grow slowly, and may invade the underlying tissues. Again, this tumour is curable by surgery or radiotherapy. The third type of skin cancer is squamous cell carcinoma SCC, which often develops from a solar keratosis or sunspot. If it is not treated early, it may spread to other parts of the body, but is again curable before that occurs by either surgery or radiotherapy. About 600 females and 1,000 males develop squamous cell carcinoma in Ireland each year. The other cancers include those of baso-squamous (mixed) carcinomas and other morphologies.
Sunshine is the single most important causative factor for all skin cancers.
Ultra-violet rays contained in sunshine are known to be harmful and can cause skin cancers. The increase in skin cancers in Ireland has been linked with the desire to have a tan, with repeated sunburn, fair skin types and genetic factors, such as number of moles.
Malignant melanoma is associated with frequent high intensity sun exposure. Whereas non-melanoma skin cancers are caused by long-term exposure to low intensity sunshine. The amount of sun exposure during childhood and frequency of sunburn are now believed to increase the risk of developing skin cancers in adult life. It is therefore most important to protect all children from intense sunshine. Hats, T-shirts and sunscreens are recommended at home, at school and on holiday.
Providing protection against the sun
Sunscreens are vital whenever exposed to strong sunlight, at home as well as abroad. Always reapply sunscreens after water sports, games or exercise. Children play outdoors during the hottest part of the day whilst at school, therefore it is wise to apply an SPF 15+ to your children before they go to school. Emulsions such as Anthelios XL contain aluminium hydroxide and can be used with infants and with highly intolerant skin. ROC make a rnumber of products in the MINESOL(TM) range, including mineral sunblock cream SPF 40, which is recommended for babies in case of inevitable exposure. This particular 100% mineral screen cream has a pleasant and almost invisible texture. During sunny periods liberal sunscreen application should become a daily routine each morning before dressing or 15 minutes before going out in the sun. Heatwaves in Ireland are not uncommon, therefore sunscreens are useful in handbags and first-aid boxes. It is important to apply sunscreens as recommended by the manufacturer. Most sunscreens identify a sun protection factor (SPF) which can range from SPF – SPF60+. The SPF is calculated by each manufacturer for their own particular product so it is important to remember that SPF may differ between brands of sunscreen. All sun protection factors are based on how long it takes for unprotected skin to burn (average length of time = 10 minutes). For example, if you use SPF 15+ the protection offered would last approximately 2-3 hours i.e. (10 minutes X 15 =150 minutes). The SPF is a rough guide only, therefore care and attention should be given to skin type, the strength of the rays or sunshine, time of day, season and latitude from the equator. Many products including Antherpos or Uvistat Lip screen or MINESOL(TM) Sun stick SPF 20 offer lip protection especially in people who are prone to recurrent herpes labialitis.
Sunbeds and solariums
Ultraviolet radiation (UVA rays) emitted from sunbeds and solariums is now known to have harmful effects on skin. Suncreams and Lotions such as Uvistat contain chemical agents and titanium dioxide and are UVA protectants. Excessive use of sunbeds can cause rapid ageing of the skin, long term damage and increase the risk of skin cancer. There is no such thing as a safe tan. Many people today use sunbeds to develop or maintain a tan. Some people believe that a suntan from a sunbed is a safe tan. Skin specialists say a tan is a sign of skin damage and advise everyone to avoid the use of sunbeds and solariums. This is especially important for the very fair skinned and persons under the age of sixteen. Likewise, persons with skin cancer or those with a family history of skin cancer should never use sunbeds or solariums.
NMS cancer statistics for Ireland
* Average of 7334 new cases per year, 1994-96: 3445 in females, 3889 in males.
* Average of 40 deaths per year: 10 in females, 30 in males.
* Age-standardised incidence rates about 48% higher in males than females.
* By far the most common type of cancer in both females and males.
* Recorded incidence rates higher in Republic of Ireland (RoI) than in Northern Ireland (NI), by about 16% for females and 26% for males, but this possibly reflects differences in registration practice.
On average each year, 3445 new cases of malignant non-melanoma skin cancer (NMS) were registered in females, 3889 in males, in Ireland as a whole. NMS cases (primarily squamous cell and basal cell carcinomas) were by far the most common category of cancer in both females and males (29% of all malignant cancer cases).
European-age-standardised rates were significantly higher among males than females, by about 48%. On average, females were estimated to have a 1-in-12 chance of developing these cancers by age 74, males a 1-in-8 chance. Median age at diagnosis was 72 years for females and 70 years for males. In the period 1994-96 only 10 deaths among females and 30 deaths among males were attributed to non-melanoma skin cancer each year. This represents about 1 death for every 200 incident cases, reflecting the fact that these cancers are rarely fatal. Reported mortality rates (EASRs) were significantly higher in males than females, by about 370% (95% confidence limits 200-645%), but inaccurate certification of causes of death may possibly contribute. On average, females were estimated to have a 1-in-6600 chance, males a 1-in-1600 chance, of dying from these cancers by age 74.
Comparison of incidence rates within Ireland
Recorded incidence rates of non-melanoma skin cancer (NMS) were significantly higher in RoI than in NI for both males and females. However, these differences may possibly reflect, in part, higher case ascertainment (completeness of registration) in RoI than NI, as a result of a more targeted effort to collate all NMS cases in RoI. Involvement of other factors cannot be excluded however.