Moles (nevi) are a common type of skin growth. They often appear as small, dark brown spots and are caused by clusters of pigment-forming cells (melanocytes). Most people have 10 to 40 moles that appear during childhood and adolescence and may change in appearance or fade over time.
Most moles are harmless. Rarely, they become cancerous. Being aware of changes in your moles and other pigmented patches is important to detecting skin cancer, especially malignant melanoma.
The typical mole is a small brown spot. But moles come in different colors, shapes and sizes:
Color and texture. Moles can be brown, tan, black, blue, red or pink. They can be smooth, wrinkled, flat or raised. They may have hair growing from them.
Shape. Most moles are oval or round.
Size. Moles are usually less than 1/4 inch (about 6 millimeters) in diameter — the size of a pencil eraser. Those present at birth (congenital nevi) can be bigger than usual, covering part of the face, torso or a limb.
Moles can develop anywhere on your body, including your scalp, armpits, under your nails, and between your fingers and toes. Most people have 10 to 40 moles. Many of these develop by age 50. Moles may change or fade away over time. With hormonal changes in adolescence and pregnancy, they may become darker and larger.
Clusters of brown spots around the eyes, cheeks and nose are sometimes called flesh moles, but they are actually dermatoses papulosa nigra — a type of seborrheic keratosis, not clusters of pigment-forming cells (nevi). Dermatoses papulosa nigra are more common among Black women. Flesh moles don’t carry a risk of melanoma, but they can be treated if you consider them a cosmetic concern.
Unusual moles that may indicate melanoma (refer to skin cancer melanoma protocol on the website)