Skip to main content
<p>With the days growing longer and the temperatures rising, Hoosiers will spend more time outdoors this spring and summer.</p>

IU Simon Cancer Center Dermatologist Offers Skin Cancer Protection Tips

And May, which is Skin Cancer Detection and Prevention Month — is a good time to refresh memories about protection from the sun.


Lawrence A. Mark, M.D., Ph.D., an assistant professor of dermatology at the Indiana University School of Medicine and a researcher with the Indiana University Melvin and Bren Simon Cancer Center, said, “You can’t see the sun’s harmful rays, you can’t feel them, but they can harm you.”

 Because of that, Dr. Mark recommends these tips for protection against the sun:


  • Apply sunscreen with an SPF of at least 30. Dr. Mark explained SPF this way: If your skin begins to redden after being in the sun for one minute, you could expect to be in the sun for 30 minutes while wearing an SPF of 30 before you see the same amount of reddening.  


  • Wear appropriate clothing, such as a wide brim hat, long-sleeved shirt, and long pants.


  • The suns rays are strongest from 10 a.m. to 3 p.m. or so. Limit long periods of time outdoors during these hours.


According to the American Cancer Society (ACS), most of the more than one million cases of skin cancer diagnosed yearly in the United States are considered to be sun-related.

 Basal cell carcinoma and squamous cell carcinoma are the most common forms of skin cancer. Melanoma is the deadliest form of skin cancer, and it can appear suddenly on any part of the body or develop from a mole. Melanoma caused about 8,110 of the 10,850 deaths due to skin cancer in 2007, according to the ACS.

 What should you look for?

 Dr. Mark tells patients to watch for what he calls the “ugly duckling” sign. “If you have a spot that just doesn’t look like any other, it is best to have a doctor examine it, just to be on the safe side,” he said.

Dr. Mark and his colleagues use the ABCD’s to evaluate melanoma:

  •  A, asymmetry: half of a mole or birthmark does not match the other half.


  • B, border: edges are irregular, ragged, notched, or blurred.


  • C, color: the color isn’t the same all over but may have differing shades of brown or black, sometimes with patches of red, white or blue


  • D, diameter: the area is larger than six millimeters (about the size of a pencil eraser) or is growing larger



Pay attention to your body and talk with your physician about any changes you notice. If detected and treated early, these cancers have a greater than 95 percent cure rate.