June 2024
Skin cancer is the out-of-control growth of abnormal cells in the outermost layer of your skin, the epidermis. Damage to cells in the epidermis can cause mutations in their growth leading to rapid multiplication and formation of malignant tumors. The main types of skin cancer are basal cell carcinoma, squamous cell carcinoma, and melanoma.
The two primary causes of skin cancer are ultraviolet radiation (UV rays) from sunlight and tanning beds, which emit 12% more UV radiation than sunlight. UV rays from the sun come in two types, UVA and UVB. UVA rays are more abundant in sunlight and less cancer-causing than UVB rays. UVA rays are associated with skin aging while inflammation and UVB rays are more likely to cause the skin to burn.
Basal cell carcinoma (BCC) is the uncontrolled growth from the epidermis. These cancers often develop on sun-exposed areas of skin, especially the scalp, face, shoulders, and back. BCC is the most common type of skin cancer, causing about 3.5 million cases per year in the US.
Squamous cell carcinoma (SCC) is caused by the uncontrolled growth of a specific type of epidermal cell called a squamous cell. Like BCC, SCC is common on sun-exposed areas and is the second most common skin cancer.
Melanoma is a skin cancer that develops from cells called melanocytes. Melanocytes produce the pigment melanin, which gives skin its color. Melanomas often look like moles and appear anywhere on the body, even areas not exposed to sun. They occur most often in individuals who have had sunburns and can be triggered using tanning beds. The Melanoma Research Alliance states that the lifetime risk of developing melanoma varies across skin tones/ethnicities (White: 1 in 40, Black: 1 in 1000, Hispanic: 1 in 200). Melanoma is the most dangerous type of skin cancer but is curable when treated early. An acronym to assist with screening for melanoma is the ABCDE rule. This stands for Asymmetry, Border, Color, Diameter, and Evolving. It can be more difficult to spot abnormal skin growth if you have dark skin, so watch for any growths that change, grow, itch, or bleed.
Skin cancer prevention
Getting sunburned can increase the risk of skin cancer but it is not the single, more severe events that increase your risk as much as the cumulative effects of daily exposure. Each time you run errands, walk the dog, or take a drive without sun protection you add to the damage that can lead to dark spots, wrinkles, leathery skin, and skin cancer. No single method of sun protection will give you all the coverage you need, so healthcare practitioners recommend a few strategies to prevent UV damage.
Clothing with built-in UV protection is one method. Look for the UPF on the label, which stands for ultraviolet protection factor. The number indicates the amount of UV radiation that will reach your skin through that fabric. For example, a UPF 50 fabric will allow just 1/50th of the original UV light. Lightweight fabrics with breathability, long sleeves, and pants, regardless of UPF, will help protect your skin. Wearing a hat with a brim of at least 3 inches will protect your face, ears, eyes, and neck and UV-blocking sunglasses will protect your eyes. Any remaining exposed skin should have sunscreen applied, including your hands, and don’t forget to reapply after handwashing.
Another strategy is to choose shade during the peak hours of sun intensity, between 10:00 a.m. and 4:00 p.m. Walk on the shady side of the street or sit under an umbrella, awning-covered porch, or tree. Consider the sunlight passing through the tree leaves or reflecting off water, sand, glass, or concrete, and use adequate sunscreen for protection.
There are many types of sunscreens, but the SPF (sun protection factor) is the most important element. SPF ratings represent how long it would take for skin to become reddened when using a particular sunscreen, compared to when using no sunscreen. For example, an SPF 15 sunscreen, applied as directed, would protect you from sunburn for 15 times longer than no sunscreen. Broad-spectrum sunscreens contain ingredients that protect the skin from UVA and UVB radiation. Sunscreens are not waterproof but will indicate a water-resistance period, usually 60-80 minutes. Sunlight reflecting off water can increase your risk of burning, so reapply sunscreen regularly during water sports. It is vital to apply sunscreen appropriately: applying liberally, having someone assist you to avoid missing hard-to-reach spots, and reapplying as directed. Use a broad-spectrum sunscreen with a minimum SPF rating of 15. When outdoors for an extended period consider SPF 30 or greater. Children under six months should be screened from sun exposure rather than using sunscreen. Sunscreen is safe for children over six months. Hats, sunglasses, and stroller awnings can help protect your child from sunburn.
The Skin Cancer Foundation recommends that adults do monthly skin self-exams and see a dermatologist annually or more frequently based on their skin health. Have a partner or family member assist you or use a hand-held mirror to examine your skin. At Block Island Health Services, we can help with a skin examination, perform skin biopsies, and refer you to a dermatologist if needed. Additional information about skin cancer is also available in our waiting room for your convenience.
– Laurie Anderson, APRN-C, CDOE