Does Sunscreen Prevent Malignant Melanoma?

Does sunscreen prevent malignant melanoma? The short answer is not necessarily. Two reasons why:

1. People slather it on and then bake in the sun twice as long they should.

2. Some sunscreens are not broad-spectrum. In other words they protect against UVB rays but not UVA rays, which may also cause skin cancer — including malignant melanoma, which can be deadly.

Last year the FDA issued new sunscreen guidelines for manufacturers.

  • In order to claim that a sunscreen protects against skin cancer, it must be at least SPF-15 and must protect against UVB and UVA. If the claim can’t be made, a warning must be added to the label: “This product has not been shown to prevent skin cancer or premature skin aging.”
  • No sunscreen is really waterproof so only the term water-resistant can be used and only if studies prove that the product retains its value after being exposed to water.
  • The term sunblock can no longer be used, because no sunscreen can completely block the sun.

Even if you choose the right kind of sunscreen, you also have to use common sense. Here are some recommendations from the American Board of Family Medicine:

How to use sunscreen

  1. Don’t put on sunscreen and then stay in the sun so long you get a sunburn.
  2. If your skin starts to get red or feel uncomfortable, don’t just reapply sunscreen, cover up or get in the shade.
  3. Wear protective clothing, a hat, and sunglasses along with sunscreen.

The goal isn’t to avoid getting any sun exposure at all — in fact, sunlight is an important source of Vitamin D. The recommendation is that we get from five to 30 minutes of sun exposure between 10 am and 3 pm at least twice a week to our face, arms, or back.

What you want to avoid is sunburn because sunburns increase your risk of developing malignant melanoma.

Did you know malignant melanoma is now the most common cancer among people 25 to 29 years old? The Mayo Clinic just published research that showed the incidence of malignant melanoma has increased more than sixfold in the past 40 years. Multiple studies have shown a strong connection between sunburns during childhood and adolescence and malignant melanoma.

Dr. Frederick Aronson, a cancer specialist at Maine Center for Cancer Medicine in Scarborough says, “Most of the ultraviolet radiation that causes melanoma is delivered to the individual at risk before age 20. There are migration studies that show if you grow up in a high sun region and move to a lower sun region in your 20s, your melanoma risk is as if you lived in the high sun region all your life and vice versa. If you live in a low sun region and move to a high sun region in your 20s your melanoma risk remains relatively low.”

The National Cancer Institute lists a number of melanoma risk factors we should be aware of:

Malignant melanoma risk factors related to sunlight

  • Fair-skinned with blue or green eyes, or red or blond hair
  • Live in a sunny climate or at a high altitude
  • High exposure to strong sunlight
  • Have had one or more blistering sunburns during childhood
  • Use tanning beds

Non-sunlight related risk factors

  • Close relatives with a history of melanoma
  • Come in contact with cancer-causing chemicals such as arsenic, coal tar, and creosote
  • Certain types of moles (atypical dysplastic) or multiple birthmarks
  • Weakened immune system due to disease or medication

Mike Cushman and granddaughter Keira

Mike Cushman, who lives in South Portland, was diagnosed with advanced malignant melanoma in 2010. He has a story to share about the importance of catching it early. “I had a suspicious mole on the back of my head under my hair,” he recently described to me. “My daughter spotted it and suggested my doctor check it out. The biopsy came back benign. Late July I felt a lump in that same area. In early August it was removed for biopsy and came back malignant melanoma. I cannot trace the melanoma to my family. I seem to be the only one. As a child growing up in the 50s and 60s I probably had my share of sunburns.”

Surgery is the most effective treatment for malignant melanoma. Depending on a variety of factors, chemotherapy, radiation therapy, and immunotherapy are also used to treat melanoma. Each comes with some serious side effects. Several promising new treatments are now being studied in clinical trials, including a targeted therapy that has offered a great deal of hope to Mike. The treatment targets a mutated gene found in about half the people diagnosed with metastatic malignant melanoma.

“I am on a GlaxoSmithKline Phase 1 Clinical Trial BRF113220. It is a combination of a Braf and MEK protein inhibitor. It is a targeted therapy. I have a Braf mutation in the cancer cells, which allowed me to be a candidate for a trial. I am doing very well. I have been on this treatment for 15 months. My CT-Scans continue to show stable tumor size and no new tumors. That is always good news.”

Dr. Aronson says targeted therapies are hopefully, “the future of cancer treatment in the universe, where we don’t rely on the immune system to fight the cancer, but we identify a mutation in the cancer cell that is driving the cancer cell to proliferate and survive and cause trouble in your body. We specifically design in the laboratory a small molecule that can target that particular mutant process and cripple it. Because it’s specific to the tumor cell the side effects from the treatment are much less.”

The new approach to treating cancer holds a great deal of promise, but the real keys to treating malignant melanoma are preventing it in the first place and learning how to identify it as early as possible. The first signs are often changes in an existing mole, but it can also show up as a new mole.

Signs of melanoma in a mole

  • Asymmetrical shape — one half doesn’t match the other
  • Borders are irregular — ragged or blurry edges or pigment that spreads into surrounding skin
  • Color is not even — usually shades of brown, black, and tan, but sometimes white gray, red, pink or blue
  • Diameter — usually bigger than a pea, but can start tiny and get bigger
  • Evolving appearance — a change that happens in just weeks or months.

What malignant melanoma might look like

Courtesy National Cancer Institute

Courtesy National Cancer Institute.

Mike says at his age he chooses not to dwell on sunburns he got when he was younger. “I cannot go back and undo the past. What I would have done differently is talk to my doctor about follow up care with a dermatologist. I am very thankful that my daughter brought to my attention the suspicious mole on the back of my head. My two daughters now have a family history of melanoma and they see a dermatologist at regular intervals. Believe me, I ask them if they have been going to their appointments.”

Mike recently wrote an essay about his cancer experience for My Generation Magazine.

If you’ve been meaning to get screened for any suspicious moles or are worried about one in particular, you’re in luck because three FREE SKIN SCREENINGS are being held in southern Maine in May from 6:00 pm to 8:00 pm:

Wednesday, May 16
Maine Medical Center Cancer Institute
100 Campus Drive

Monday, May 21
SMMC Saco Health Center
13 Industrial Park Road

Tuesday, May 22
Mercy Oncology-Hematology Center
Fore River Medical Building
195 Fore River Parkway, Suite 360

You need an appointment. Call 1-877-831-2129 to schedule. Space is limited and patients who have never been screened by a dermatologist will be given priority.

If you have an extra five minutes take a look at this video about melanoma. I thought it was pretty clever.