Spring is here again with its beautiful colors and promise of new beginnings. However, on some days, it feels like we are in the middle of a sweltering summer heat storm with temperatures reaching as high as 98ºF! After spending a month on a dermatology rotation evaluating people for skin cancer and participating in procedures to excise these lesions, I am now very aware of the potential damage, sometimes even life-threatening, that harmful sunrays can cause. I strongly believe that we need to be more proactive at taking better care of ourselves and reducing our risks of developing skin cancer. The piece below was previously featured in our May 2009 edition. However, I hope it serves to re-equip you with the information needed to make good skin care decisions.
Skin cancer
Like many other skin-related diseases, skin cancer can be categorized into two main groups: melanoma and non-melanoma. In 2007, there were approximately 59, 940 cases of melanomas reported in the U.S. compared to over 1 million non-melanomas. Most of these cases were due to exposure to harmful ultraviolet (UV) radiation in sunlight. Each year, 10,850 people die from skin cancer and of this total more than 8,110 would have had melanomas, making it the most serious type of skin cancer.
Melanomas
As the name suggests, it originates from cells in the skin called melanocytes that produce the pigment melanin. Melanin has two functions: it gives the skin its color and protects the deeper sections from the harmful UV radiation in sunlight. Melanocytes increase their production of melanin depending on the duration of their exposure to sunlight which results in tanning. However, when overexposed, they can be stimulated to grow abnormally and become cancerous. Doctors can tell melanomas apart from the natural spots and moles on our bodies by looking out for four basic characteristics: asymmetry, border, color and diameter. This underscores the importance of frequently examining your skin, taking note of the spots and moles you have, and reporting changes immediately to your physician who will be able to determine if further examination is warranted. Although they can occur anywhere, melanomas tend to appear on the upper body, between the shoulders and hips and sometimes on the head and neck in men but mainly on the lower legs in women. In dark-skinned people, melanomas hide under the fingernails or toenails and on the palms of the hands and soles of the feet.
Non-melanomas
There are several types of cancers that fall under this category but the two most common ones are basal cell and squamous cell cancers.
Basal cells are the most common (~ 1million yearly) form of skin cancers affecting mainly people with fair skin, blond or red hair and blue, green or gray eyes. There are generally five distinguishing characteristics that doctors use to help identify this type of cancer: 1) a persistent non-healing bleeding sore; 2) a reddish patch on the face, shoulders, chest, arms or legs that sometimes crusts, itches or hurts; 3) a shiny, pearly bump or mole-like structure that can be pink, red, brown or black; 4) a pink scaly growth with elevated borders and a red indented center that sometimes bleeds and 5) a shiny scar-like area with poorly defined borders.
Squamous cell cancers are the next most common (~250,000 cases yearly) occurring in the upper layer of the skin’s epidermis. Also a result of excessive sun exposure, squamous cancers tend to show up on parts of the body that are left exposed for long periods such as the rim of the ears, lower lip, scalp (especially in bald people) and the arms and legs. However, sometimes they can be found around the genitalia. Interestingly, African-Americans are also at a high risk for squamous cell cancers. Scientists have found that people who use sun-tanning beds are 2.5 times more likely to develop this form of cancer than those who do not. When detected early and removed, they are usually curable.
Prevention
The American Cancer Society makes the following recommendations for preventing skin cancer1:
- Avoid the sun between 10 a.m. and 4 p.m.
- Seek shade: Look for shade, especially in the middle of the day when the sun’s rays are strongest.
- Slip on a shirt: Cover up with protective clothing to guard as much skin as possible when you are out in the sun. Choose comfortable clothes made of tightly woven fabrics that you cannot see through when held up to a light.
- Slop on sunscreen: Use sunscreen and lip balm with a sun protection factor (SPF) of 15 or higher. Follow these practices to protect your skin even on cloudy or overcast days. UV rays travel through clouds.
- Slap on a hat: Cover your head with a wide-brimmed hat, shading your face, ears, and neck. If you choose a baseball cap, remember to protect your ears and neck with sunscreen.
- Wrap on sunglasses: Wear sunglasses with 99% to 100% UV absorption to provide optimal protection for the eyes and the surrounding skin.
- Avoid other sources of UV light. Tanning beds and sun lamps are dangerous because they can damage your skin.
Choosing Sunscreens
Sunscreens provide some but not 100% protection form UV light so it is important to follow the other recommendations listed above. However, they have been proven to be quite effective when used regularly and properly. It is important to read all labels of products that advertise themselves as sun-protectors since some contain far fewer levels of SPFs than recommended by the Food & Drug Administration (FDA). SPF stands for Sun Protection Factor and it is rated on a number system based on how much protection against UVB (a type of UV radiation) a product offers. The higher the SPF number the better, but an ideal figure is 15. SPFs can be found in lotions, creams, lip balms and some make-up.
When applying sunscreen, it is important to apply generous amounts to sun-exposed regions according to instructions outlined on the product and to reapply frequently especially after swimming or perspiring. Check the product for an expiration date and discontinue use if this has passed. And also be aware that some products can cause allergic reactions to people with sensitive skin so speak with your doctor if you have had problems in the past. For reasons discussed above, it is very important that people of color use sunscreen frequently to avoid skin cancer. It should be viewed as an added layer of protection to that of the natural melanin which provides the dark, rich complexion.
Resources:
1) American Cancer Society. http://www.cancer.org/docroot/PED/content/ped_7_1_What_You_Need_To_Know_About_Skin_Cancer.asp?sitearea=&level=
2) Melanoma.com
3) The Skin Cancer Foundation. www.skincancer.org
4) Fig 1 from : http://media.smays.com/livinghealthypodcast/skincancer.jpg