How UV rays cause skin cancer
Figure 1 (Bowen, 2013)
Figure 2 (WiseGEEK.com, n.d)
Skin peeling due to sunburn
Figure 3 (womenshealth, 2014)
Freckles due to sun exposure
What is skin cancer
Skin cancer is the most common form of cancer among men and women, for every cancer diagnosis skin cancer counts for 50% of those. 90% of all skin cancer is caused by sun exposure. The sun gives off UV rays, these rays come in 3 main forms UVA,UVB and UVC. UVA rays age skin cells and damage DNA. They are linked to long term skin damage such as wrinkles. Tanning beds give off massive amounts of these rays and they increase skin cancer risk. UVB rays are a bit more powerful than UVA rays. They can damage skin cells directly and are the main cause of sunburns and are thought to cause most skin cancers. UVC rays are more powerful than any other types but the earths atmosphere blocks them from reaching us and they are not in sunlight (American Cancer Society, 2017). All these types of rays have different wavelengths and strengths.
They cause different types of cancer. The cancer almost always starts off as Melanoma, this is the most dangerous form of the cancer but can almost always be cured if it is spotted early. However, these cancerous growths grow under UV damaged skin and if it is not found early they mutate and form tumours. These tumours appear in the pigment producing melanocytes in the basal layer of the epidermis The most common of these types is Melanoma, this most often develops from a mole. A way to look for this is if your getting new moles appearing on your skin or if a mole is growing or changing colour or shape. If this is the case go to your doctor and get the mole checked. If you noticed the mole changing early then the cancer will be in an early stage and the doctor will refer you to a dermatologist and they will be able to extract it. The other main types of non-melanoma cancers are Basal cell cancers (BCC) and squamous cell cancers (SCC). They are named after the areas of skin they occur in. BCC cancers are the most common type of non-melanoma cancer, about 75% of non-melanoma cancers are BCC. They develop mostly in areas of skin exposed to the sun including parts of the face such as the nose, forehead and cheeks. Also, on your back or lower legs. It is most often diagnosed in people who are middle or old age. Your doctor might also call your basal cell carcinoma a rodent ulcer. There's a number of different subtypes, each can look and behave differently. These include:
About a half of BCCs are the nodular type. It's very rare for basal cell skin cancer to spread to another part of the body to form a secondary cancer. It's possible to have more than one basal cell cancer at any one time and having had one does increase your risk of getting another. (Cancer Research UK, 2016). SCC is generally faster growing than basal cell cancers. About 20 out of every 100 cases (20%) of skin cancers are SCC. They begin in cells called keratinocytes, found in the epidermis layer of the skin. Most SCCs develop in areas that have been exposed to the sun. These areas include parts of the head, neck, and on the back of your hands and forearms. They can also develop in scars, areas of skin that have been burnt in the past, or that have been ulcerated for a long time. SCCs don't often spread. If they do, it's most often to the deeper layers of the skin. They can spread to nearby lymph nodes and other organs causing secondary cancers, but this is unusual.(Cancer Research UK, 2017) Overall skin cancer is a horrible disease that is still haunting almost everywhere on the planet.
Figure 4 (cancer research UK, 2016)
Figure 5 (cancer research UK, 2016)
Prevention and Treatment
- Seek the shade, especially between 10 AM and 4 PM.
- Do not burn.
- Avoid tanning and UV tanning beds.
- Cover up with clothing, including a broad-brimmed hat and UV-blocking sunglasses.
- Use a broad spectrum (UVA/UVB) sunscreen with an SPF of 15 or higher every day. For extended outdoor activity, use a water-resistant, broad spectrum (UVA/UVB) sunscreen with an SPF of 30 or higher.
- Apply 1 ounce (2 tablespoons) of sunscreen to your entire body 30 minutes before going outside. Reapply every two hours or immediately after swimming or excessive sweating.
- Keep newborns out of the sun. Sunscreens should be used on babies over the age of six months.
- Examine your skin head-to-toe every month.
- See your physician every year for a professional skin exam. (Skin Cancer Foundation, 2015)