A recent Nature Outlook, supplement to Nature Magazine, was devoted to melanoma. Melanoma is the deadliest form of skin cancer, and incidence of melanoma is increasing throughout the world. This supplement has several articles on the latest research as well as myths and facts about melanoma. I have incorporated the links to the various articles (available without a subscription) as answers to common questions on skin cancer and sun protection.
Which country has the highest incidence of melanoma in the world?
Australia has high solar ultraviolet levels, lots of beaches, and a large number of fair-skinned people. Melanoma rates were on the rise until the 1990s when the incidence of melanoma plateaued. According to “Prevention: Lessons from a Sunburnt Country,” the reason why melanoma rates plateaued in Australia and are decreasing among young people is: 1) An aggressive ad campaign was started in the late 1980s raising awareness of the dangers of sun bathing; 2) Melanoma had become so common that most people knew at least one person with it; 3) Now, more adolescents do not prefer a tan compared to those who do.
Have scientists made sunblock in a pill form?
Not one that has been FDA approved
While some supplements claim to fight sun damage, they are not FDA approved, which means there is no way to know how well they work and if they are effective in preventing sun damage. Supplements have looser regulations compared to sunscreen lotion, which is considered both a cosmetic and a drug. Sunblock (in lotion form) is still the best way to prevent sun damage.
Scientists have been working on a pill that contains antioxidants since sun damage is often caused by free radicals and antioxidants destroy free radicals. The trouble is getting the antioxidants from the digestive system to the skin. For more information, see “Protection: The Sunscreen Pill.”
Side Note: The FDA has not approved a new sunblock ingredient in twelve years even though other countries have incorporated newer ingredients into their sunblock (lotions). See “Perspective: Protect the USA from UVA” for one perspective on why the U.S. has lagged in approving new ingredients.
What about the spray-on sunblock? Does it work just as well as the rub-on lotion?
Spray-on sunblock uses FDA approved ingredients; however, according to a dermatologist I talked to, the spray-on sunblock does not work as well as the kind that you rub onto your skin. It is better to rub the sunblock into your skin for best sun protection, and people tend to not use enough sunblock when they use the spray. Also, sunblock, while it can prevent sun damage, is still not as effective as wearing a hat and protective clothing.
What are the stages of melanoma and what do they mean?
Melanoma is only one of several types of skin cancer, but it gets a lot of attention because it is the most deadly. It starts in cells called melanocytes (the cells that make melanin), usually in a mole, and is often directly related to UVA/UVB exposure as well as genetics.
Nature’s “The Cancer that Rises with the Sun” has an excellent graphic explaining the four stages of melanoma.
Briefly they are:
- Stage 0: Melanoma cells are only on the top layer of skin.
- Stage 1: Melanoma may be 2mm thick, has not spread to lymph nodes or anywhere else, and can be removed with surgery.
- Stage 2: Melanoma may be up to 4mm thick, has not spread to lymph nodes or anywhere else, and can usually be removed with surgery.
- Stage 3: Melanoma cells have spread deeper into the skin, lymph vessels, or nearby lymph glands. Can be removed with surgery, but often returns.
- Stage 4: Melanoma has spread to other parts of the body, and treatment and survival depends on where it has spread.
Is a diagnosis of stage 4 melanoma a death sentence?
It used to be, but now the survival rate is much higher. Since 2011, the FDA has approved seven new treatments for melanoma and there are others in clinical trials. Many of these are based on immunotherapy. See “Drug Development: A Chance of Survival” for a good overview of where we are in melanoma treatment research.
Can people with darker skin get melanoma?
While skin cancer is less common in people who have higher levels of melanin (pigmentation), when melanoma does occur in those who are naturally darker skinned, it is often more deadly and not always due to sun exposure. Also, keep in mind that the risk factors are related to levels of melanin, not man-made racial distinctions. There are people from all races and countries that naturally have more or less melanin. Those with less are at a higher risk.
Bob Marley is one famous example of someone with darker skin who died from melanoma that began in his big toe and eventually caused a brain tumor. Furthermore, he is an example of how melanoma is not a cancer of old age. He was diagnosed at age 32 and died at age 36. See “Skin Colour: No Hiding in the Dark” for info on melanin and melanoma.
The lesser of two evils: Avoid the sun to protect against melanoma or get some sun for vitamin D to stave off osteoporosis?
Vitamin D is related to bone health, and may be related to other health factors, although more research is needed in this area. The best way to get vitamin D is from sun exposure, but sun exposure increases one’s risk of skin cancer. One option is to avoid the sun and take vitamin D supplements. Another option is to get some sun exposure during non-peak hours, such as early morning or late evening. “Prevention: Lessons from a Sunburnt Country” has more information on this partway through the article.