Skin cancer affects three different types of skin cells and each type of skin cancer, and the stage of progression, determines the likely prognosis of the skin disease.
Squamous cell skin cancer involves the thin flat cells found at the surface of the skin and is one of the most common forms of skin cancer but is often treatable.
Basal cell skin cancer is found in the cells lying beneath the squamous cells and, as such, a little deeper into the body and with a slightly higher degree of risk of going unnoticed for longer.
Melanoma is both less common and more deadly than the other types of skin cancer and occurs in the melanocytes some of which are found in seemingly unlikely places such as the eyes, vagina, mouth, and under the fingernails.
Skin Cancer Rates
In the US each year more than 70,000 people are diagnosed with melanoma and there are nearly 10,000 deaths from this type of skin cancer alone. In the UK the number of cases falls closer to the 7000 mark and there are around 6000 cases in Canada.
Cases of squamous cell carcinoma and basal cell carcinoma (known collectively as nonmelanoma skin cancer) in the US average more than 1million each year but there are less than a thousand deaths associated with the condition. In the UK there are around 100,000 cases of nonmelanoma skin cancer each year and usually less than 500 deaths from this form of cancer.
Skin Cancer Causes
In the UK there is a peculiar correlation between skin cancer and affluence with one set of statistics from the early to mid nineties showing nearly double the incidence of melanoma in richer areas of Scotland than in more deprived areas.
Explanations offered for such startling differences include access to holidays abroad (with stronger sunshine) as well as the possibility that those with higher incomes seek medical attention more frequently and are therefore diagnosed more often than less affluent patients.
The gap does appear to be narrowing which suggests that the overseas holiday connection played a significant role in the difference. This highlights the major contribution of ultraviolet radiation to skin cancer development and the likely importance of effective sunscreen use.
Other contributors to skin cancer include genetic disorders, smoking, and exposure to carcinogens such as some chemicals found in toiletries or cleaning products.
Skin Cancer Diagnosis
A qualified dermatologist will most often be enlisted to help determine if a skin abnormality is likely to be cancerous. A patient with more than fifty moles or with moles that are large, unusually coloured or textured, and which have an irregular border may be biopsied to test for skin cancer.
Unusual blemishes, skin sores that do not heal, and skin spots that bleed or ooze, or are pruritic (itchy) may also warrant further investigation to check for cancer. A new diagnostic tool called MelaFind has recently been approved for use in the US and Europe to assess the likely need for skin biopsy in cases of melanoma but not for other types of skin cancer.
Skin Cancer Treatment
The treatment of skin cancer depends largely on the type, the location, the stage of the cancer, and the health of the patient in general. Many skin cancers can be removed completely during biopsy as they are localised, requiring no further surgery or treatment.
Other cancers that have spread may require further surgery including a skin graft and treatment with chemotherapy, radiation therapy, or biologic agents to enlist the help of the body’s own immune system to fight skin cancer naturally.