(A last THANK YOU to Dr. Martin for sharing his extensive experience with us!)
Summer vacation is still in full force for college students and that means more time in the sun. From a doctor’s point of view, do be careful. Why? Melanoma accounts for 5 % of skin cancers but causes nearly 80% of the skin cancer mortality. It’s more common in women than in men, and is increasing 3% annually in women between 15 and 39. It’s very aggressive, but, for most people, can be prevented. If caught early enough, before it has spread, it’s curable.
There are risk factors for melanoma. The strongest are a previous melanoma, a family history of melanoma or a family history of multiple benign or atypical moles. Other risk factors are sun sensitivity, immunosuppression and exposure to UV radiation. Many of the genetic mutations predisposing someone to melanoma have been identified. But for most of these, the genetic abnormality needs an environmental trigger, such as UV light, that ultimately leads to melanoma.
Ultraviolet light damage induces the production of the pigment, melanin by stimulating the production of a hormone (melanocyte stimulating hormone) that causes a melanocyte (a melanin producing cell in the epidermis) to produce melanin that protects the skin against UV light. This is reaction results in a tan. Some light-skinned, redheaded people genetically lack this protective response of producing melanin and higher rates of melanoma (one of the many different known mutations that can predispose someone to melanoma)
Does this tanning response to UV light reduce the risk of skin cancer? In theory, melanin does reduce the damage caused by UV light; this is why dark -skinned people , although still at risk, are less likely to get skin cancer. BUT, while more melanin is produced in response to damaging UV light, the UV light can cause mutations in the DNA that can lead to melanoma. The effects of UV light on the DNA are dose dependent and the type of sun exposure seems to be important. Sunburns and intense, intermittent exposure seem to be worse than low-grade, chronic exposure.
Tanning booths (a multi-billion dollar industry!) are carcinogenic. The relative risk of melanoma is about two fold. The booths emit more UVA that still damages the skin without burning it. Because you don’t burn so much, you are deceived into thinking that the UV light exposure is ok. It’s not. All the aging and carcinogenic effects of UV light exposure are in tanning booths. Stay out of them!
What does a melanoma look like?
If you have a new mole or a mole that looks worrisome, you should see a dermatologist right away (remember, if caught early, a melanoma can be cured).
Early signs of melanoma are summarized by the mnemonic “ABCDE”
▪ Borders (irregular)
▪ Color (variegated), and
▪ Diameter (greater than 6 mm (0.24 in), about the size of a pencil eraser)
▪ Evolving over time
What should you do this summer to reduce your risk?
-Avoid direct sun from 10 to 4
-Wear protective clothes including sunglasses and a hat
-Buy a GOOD sunscreen (for ratings see: http://breakingnews.ewg.org/2011sunscreen/)
-Use a broad spectrum sun screen of SPF 15 or more and use plenty of it (1-2 ounces for face, arms and legs)
-Apply the sunscreen at least 30 minutes before going outside
-Reapply the sunscreen every 2 hours
-Sun screens deteriorate in the bottle and last about 2 years.
-Some medicine like Retin A and some birth control pills increase photosensitivy. Check your medicines (www.melanomacenter.org/prevention/medications.html).
The Doctor Behind the Medicine:
Dr. Martin went to medical school at UCSF. He has now retired from his long and brilliant career as an anesthesiologist, now playing guitar and making bread on his spare time. Dr. Martin and three associates have started a delicious commercial wine, MC4. For those who are 21 and older, I advise you to check out MC4-- cheers!