Is your sunscreen keeping you sun safe?

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Dana-Farber experts offer tips for protection from the sun

Stephen Hodi, MD, recommends checking your sunscreen bottle for an expiration date.

As the weather grows warmer, people's thoughts turn to outdoor activities and enjoying the sun. Dana-Farber Cancer Institute physicians and nurses encourage people to avoid the dangers of overexposure to the sun when they are outside, whether they are spending a day at the beach or a few hours working in their yard.

Sunscreen is an important first line of protection against sun exposure, but experts warn that some of the ingredients can lose their effectiveness over time. Bottles that have been sitting on the shelf for more than a year may not provide adequate protection.

"Remember to look at the expiration date on the bottle of sun block," explained Stephen Hodi, MD, clinical director of the Melanoma Program at Dana-Farber. "In general, if your sunscreen does not have an expiration date, we recommend that you change your bottle of sun block yearly."

Prevention and early detection are critical to reducing the dangers of skin cancer and melanoma.

"Warm weather is a great motivator for people to get outside and reap the health benefits of being more active," said Hodi.

"At the same time, it is important that people protect themselves from the sun and make themselves aware of the signs and symptoms of skin cancer and melanoma to greatly reduce their risk of developing these preventable but dangerous diseases."

Along with replacing sunscreen yearly, here are other sun safety tips to remember:

The American Cancer Society estimates that more than one million Americans are diagnosed with basal cell or squamous cell cancers each year, and more than 60,000 will be diagnosed with melanoma, the most serious form of skin cancer. Melanoma accounts for more than 8,400 cancer deaths in the United States each year.

Melanoma can be hereditary; people with family members who have had melanoma are at a higher risk of developing the disease. Certain types of moles, excessive sun exposure and sunburns can also increase a person's risk of developing not only melanoma but other skin cancers as well.

Skin cancers present a range of symptoms. Basal cell carcinomas usually appear as flat, firm, pale areas or as small, raised, pink or red waxy areas. Squamous cell cancer may appear as lumps with rough surfaces or as flat, red patches that grow slowly. Melanoma symptoms include changes on the skin, including new spots or moles or existing spots or moles that change in shape, size and color.

Recognizing changes on the skin is key for early detection and treatment of skin cancers. The American Cancer Society recommends using the ABCD rule to help determine when a skin or mole change should be seen by a physician:

People who experience any of these symptoms should notify their physician immediately. Some skin cancers can be treated in a physician's office; malignant melanoma may involve more complex care, including surgery and radiation therapy.

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  • Apply a sun block with a rating of SPF 30 or higher;
  • Reapply sun block every two hours, and immediately after swimming or heavy perspiration;
  • Provide additional protection by wearing a broad rimmed hat, sunglasses, long-sleeved shirts and pants; and
  • Avoid excessive exposure to the sun, especially during the peak hours of 10 a.m. to 4 p.m.
  • A for asymmetry: one half is differently shaped than the other
  • B for border irregularity: jagged or blurred edges
  • C for color: the pigmentation may not be consistent
  • D for diameter: moles greater than six millimeters (the size of a pencil eraser)

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