Now that spring is here and the outside is calling, it is important to protect your skin from harmful ultraviolet (UV) rays. Skin cancer is the most common cancer in the United States.

There are three types of skin cancer: 

• Basal cell carcinoma
• Squamous cell carcinoma
• Melanoma

Each type is named after the cells the cancer develops in. Our skin is made up of two layers:  the epidermis, the outer layer, and the inner dermis layer. Melanoma starts in the melanocytes, which are found in the deepest layer of the epidermis.

People who burn easily or tan poorly are much more likely to develop skin cancer. Those that also have a large number of abnormal moles may have a higher risk of developing melanoma.

You can reduce your risk of all skin cancer by:

• Staying out of the sun from 11 a.m. to 3 p.m., when UV rays are the strongest
• Wearing long sleeves and hats to protect your skin
• Using sunscreen

It is best to use sunscreen that is water-resistant, has a SPF of at least 15 or higher, and offers broad-spectrum protection from both UVA and UVB rays. Sunscreen should be applied 20 minutes before UV exposure and reapplied every two hours.

Everyone should do a skin self exam once a year on their birthday to check for abnormal moles and lesions. You should look for the ABCDs of melanoma detection: 

• Asymmetry
  The mole has one half that does not look like the other.
• Border
  The mole is irregularly shaped.
• Color
  The mole’s color changes form one area to the next.
• Diameter
  Look for moles larger than six mm.

By checking each year you can keep track of how your moles change over time. If you see any changes or the mole itches or bleeds, you should visit a dermatologist to have it examined.

Cancer Information Service
Holden Comprehensive Cancer Center
UI Hospitals and Clinics
200 Hawkins Drive, 4802 JPP
Iowa City, Iowa 52242
Toll-free: 1-800-237-1225
cancer-information@uiowa.edu