Moles are clusters of melanocytes in your skin—that is, a concentrated collection of the cells that produce pigment. They can be flat or raised; round or oval; tan, brown, black or pink. Most are benign (not cancerous), but some aren’t. You should see a doctor if a mole has a sudden change in appearance, irregular coloring or borders, or a diameter larger than six millimeters.
READ MORE: Guide to Common Skin Spots
