A mole is a benign cluster of pigment-producing cells (melanocytes) that grows in or just under the skin. Most people carry a number of moles by adulthood, and most are acquired — they appear gradually through childhood, adolescence, and the twenties rather than being present at birth. A smaller number are congenital, present from birth, and are typically followed rather than removed unless they are large or change.
Moles are removed for two distinct reasons, and the reason shapes how the removal is approached. A cosmetic or mechanical reason — a raised mole on the face that the patient wants gone, or one that repeatedly catches on a razor, collar, or strap — is planned as an elective procedure once the lesion has been examined and looks typical. A medical reason — a mole that has changed in size, shape, colour, or texture, or one that looks atypical on examination — is planned as a diagnostic excision, where the point of the procedure is a tissue answer rather than only an appearance change. Both routes start with the same clinical examination.