Anaplastic nevus is a congenital limited self-pigmentation. The etiology of the disease is unknown. Congenital onset, clinical manifestations: onset shortly after birth, one-sided, limited or systematically distributed depigmented white spots that do not enlarge. It persists throughout life. Clinical manifestations Can occur in any race, male or female. The white spots may expand proportionally with the development of the body. The pigmentation in the depigmented area does not regenerate, so it cannot disappear naturally. The lesions are usually found on the trunk, lower abdomen, proximal extremities, and the face and neck can also be involved. The lesions are often distributed along the nerve segments, and the extremities are mostly in strips or bands, while the trunk may be square. The depigmented spots may be scattered and distant from each other. The damage is pale white limited hypopigmented spots of different sizes, the depigmentation is not complete, not as obvious as vitiligo, the boundary is blurred and irregular, sometimes the edge is serrated, almost no pigmentation halo around, which sometimes can be mixed with light brown corn to lentil freckle-like spots, but no excessive pigmentation phenomenon. Hair pigmentation may be reduced in the depigmented area, especially in the pubic hair and eyebrows. If the damage occurs in the trigeminal region, neurological symptoms and epilepsy may be associated.