Moles are small, colored (pigmented) marks on the skin. They have no known purpose. Many moles appear before age 30. But they also often increase as people age. Moles most often aren't cancer (benign) and are harmless. But some moles become cancer (malignant). That's why you need to watch the moles on your body. And tell your doctor about any that concern you.

Moles are a type of pigmented mark. Freckles are another type of pigmented mark. They're often sprinkled across the bridge of the nose, the cheeks, and the arms. Moles can appear on any part of the body. There are many types, sizes, and shapes of moles. Most moles are solid brown. In most cases they are flat or dome-shaped, smooth, and have well-defined edges.

Most moles are benign and don't need treatment. You can have moles removed if you don't like the way they look or feel. But moles may become a problem if they appear after you are 30. Or if they change in certain ways. These moles may turn into melanoma, a type of skin cancer. Melanoma rates have increased quickly over recent decades. It's often curable if caught early. But this disease can be life-threatening, especially when not diagnosed early. Your risk for melanoma is higher if you:

• Have a lot of moles
• Have had more lifetime exposure to the sun or skin that burns easily
• Have had severe blistering sunburns
• Use tanning beds and sunlamps
• Have a personal or family history of skin cancer

To manage your risk, it's smart to check your moles for changes. Also ask your doctor to do a complete skin exam when you have a physical exam. To do this, you first need to learn where your moles are. Then check your moles each month.

You can check many of your moles each month. You can do this right after you shower and before you get dressed. Check your body from head to toe. Be sure to check hard-to-see places. These include your back, neck, buttocks, between your toes, and the bottom of your feet. You can check these areas by using mirrors or by asking someone you trust to help. Then make a list of your moles. If you find any new moles or changes in your moles, call your doctor. To check your moles, you may need:

• A full-length mirror and a hand mirror
• A stool or chair to sit on while you check your feet

If you have a lot of moles, take digital photos of them. Make sure to take photos both up close and from a distance. These can help you see if any moles change over time.

See your doctor if your moles hurt, itch, ooze, bleed, thicken, become crusty, or show other changes. Also call your doctor if your moles show any of these signs of melanoma:

• A change in size, shape, color, or height
• The sides don't match (asymmetry)
• Ragged, notched, or blurred borders
• Different colors in the same mole
• Size is larger than 5 mm or 6 mm in diameter (the size of a pencil eraser)
• Different look than the other moles around it
• It starts to itch
• It bleeds or oozes