What is the cause of skin cancer?
Causes of skin cancer
Cells involved in skin cancer
The epidermis, or top layer of the skin is where skin cancer develops. The epidermis is a thin layer that protects the skin by shedding skin cells on a regular basis. The epidermis is made up of three types of cells:
Squamous cells are the inner lining of the skin and are found just beneath the surface.
Basal cells are found underneath the squamous cells. These create new skin cells.
Melanocytes, which generate melanin, the pigment that gives skin its complexion, are found in epidermis’ bottom layer. Under the sun, the melanocytes produce more melanin to help protect the deeper layers of the skin.
The type of skin cancer and treatment options are determined by its origin.
Ultraviolet rays and other potential causes
Ultraviolet (UV) radiation, which is emitted from the sun and also found in tanning bed lights, causes more DNA damage in skin cells. However, sun exposure may not be the only cause for skin cancer that occurs on skin that is not normally exposed to sunlight. This suggests that additional variables, such as being exposed to hazardous substances or having a condition that impairs the immune system, may increase the risks of skin cancer.
Risk factors
The risk of skin cancer is increased by the presence of a number of factors, including:
1. Fair skin: Skin cancer can affect anyone, regardless of skin colour. Having less pigment (melanin) in the skin, on the other hand, provides less protection from harmful UV rays. People with blond or red hair, light-coloured eyes, freckles, or who get sunburnt easily, are considerably more likely to develop skin cancer than someone with darker skin.
2. History of sunburns: People are more likely to get skin cancer as adults if they have had one or more blistering sunburns as a child or teenager. Sunburns during adulthood are also considered as a risk factor.
3. Excessive sun exposure: People who spend a lot of time in the sun, especially is the skin is not protected by sunscreen or clothing, are at risk of developing skin cancer. Tanning, which includes exposure to tanning lamps and tanning beds, is also harmful. A tan is the skin’s injury response to excessive UV radiation.
4. Sunny or high-altitude climates: People who live in sunny, warm climates get greater sun exposure than those who live in places with colder climates. Higher altitudes, where the sunlight is the strongest, also exposes a person to greater radiation.
5. Moles: Skin cancer is more likely to develop in people who have a lot of moles or abnormal moles called dysplastic nevi. These moles, which are irregular in appearance and often larger than normal moles, are more likely to become cancerous than others. If a person has a history of abnormal moles, it is best to keep an eye on them to see if they change.
6. Precancerous skin lesions: Actinic keratoses are skin lesions that can increase the chances of developing skin cancer. Rough, scaly patches ranging in colour from brown to dark pink characterises these precancerous skin growths. They are most commonly found on the face, head, and hands of people with fair complexion and who have had their skin damaged from the sun.
7. A family history of skin cancer: Individuals have a higher risk of skin cancer if one of their parents or siblings has had the condition.
8. A personal history of skin cancer: People who have had skin cancer previously, are at risk of developing it again.
9. A weakened immune system: Skin cancer is more likely to develop in people who have compromised immune systems. This includes HIV/AIDS patients and those on immunosuppressive medications following an organ transplant.
10. Exposure to radiation: Skin cancer, particularly basal cell carcinoma, may have a higher probability in those who received radiation treatment for skin disorders such as eczema and acne.
11. Exposure to certain substances: Certain chemicals and substances, such as arsenic, are linked to an increased risk of skin cancer.
Treatment of skin cancer
The size, location, type and stage of the skin cancer will influence the treatment plan that a doctor will recommend. The healthcare team may recommend one or more of the following treatments after evaluating certain specific factors:
Cryotherapy: Cryotherapy involves freezing the growth with liquid nitrogen and then destroying the tissue as it thaws.
Excisional surgery: Excisional surgery involves removing the tumour as well as some of the healthy skin around it.
Mohs surgery: Mohs surgery involves removing the growth layer by layer and examining each layer under a microscope until no cancerous cells are evident.
Curettage and electrodessication: Cancer cells are scraped away with a long spoon-shaped blade, and the remaining cancer cells are burned with an electric needle.
Chemotherapy: To eliminate cancer cells, drugs are taken orally, administered topically, or injected using a needle or IV line.
Photodynamic therapy: Photodynamic therapy involves the employment of a laser light and medicines to kill cancer cells.
Radiation: To eliminate the cancer cells, high-powered energy beams are used.
Biological therapy: Biological treatments are intended to activate the immune system so that it can combat cancer cells.
Immunotherapy: Immunotherapy is a treatment that involves applying a cream or ointment to the skin in order to stimulate the immune system to fight cancer cells.
Protecting yourself from the sun’s harmful rays is the greatest way to avoid skin cancer. It is not always possible to prevent skin cancer. Regular skin checks, can help detect it early. It is easier to cure skin cancer if it is diagnosed and treated quickly. Other links between DNA alterations and skin cancer are being studied by scientists. A deeper knowledge and understanding of how damaged DNA causes skin cancer could lead to the development of drugs and treatments to cure and reverse or repair the damage.
Sources:
1. https://www.mayoclinic.org/diseases-conditions/skin-cancer/symptoms-causes/syc-20377605
2. https://www.cdc.gov/cancer/skin/basic_info/index.htm
3. https://www.skincancer.org/skin-cancer-information/
5. https://www.nhs.uk/conditions/melanoma-skin-cancer/causes/
6. https://my.clevelandclinic.org/health/diseases/10985-sun-exposure--skin-cancer