A harmless mole caused by a disorder of pigment-forming skin cells.

A melanocytic nevus is a harmless mole. It might also be called a skin lesion. This type of mole is caused by a disorder involving melanocytes, cells that produce a pigment called melanin.

Melanocytic nevi can be rough, flat, or raised. They can exist at birth or appear later. Rarely, melanocytic nevi can become cancerous.

Most melanocytic nevi don't need treatment. You might talk with a doctor who specializes in skin conditions, also called a dermatologist, if you notice suspicious changes in a mole.