What are Atypical Nevi

Onset: begin to appear during early childhood. The characteristic features of atypical moles are present at the time of puberty. Unlike common acquired melanocytic nevi, which stop appearing after age 30, atypical nevi continue to appear well into adulthood.
Size: ranging from 6 mm-15 mm in diameter.
Border: irregularly outlined, indistinct, and fades imperceptibly into the surrounding skin.
Color: variegated with a haphazard mixture of pink, tan, brown, and black.
Surface: irregular, often with a central or eccentric papule surrounded by a prominent macular component.
Site: anywhere in the skin but occur most commonly on the trunk and upper extremities. Affected persons often have nevi in sun-protected areas, such as the scalp, groin, buttocks, the breasts in women, and the palms and soles.
Progression: increased risk of melanoma, most often the superficial spreading type.