Halo naevi

Halo naevi, also known as leukoderma acquisitum centrifugum. Halo nevi are common benign skin lesions that represent melanocytic nevi in which an inflammatory infiltrate develops, resulting in a zone of depigmentation surrounding the nevus. They appear as one or more uniformly colored, evenly shaped, round or oval nevi centrally with even peripheral margins of hypopigmentation. The central nevus may be tan, pink, or brown.

The size of the halo is variable but is normally of uniform radial distance from the central nevus. Halo nevi are usually seen in young people. Halo nevi are found most commonly in children. The average age of beginning is 15 years. All races are liable to the development of these lesions. A familial tendency for halo nevi has been reported. The mole portion tends to flatten and may disappear completely. The white area may stay if the mole disappears, or the normal skin color may return.

Halo nevi are sometimes seen in people with vitiligo. As many as 50% of affected individuals have more than one halo nevus. Halo nevi may arise in patients with malignant melanoma. Atypical moles are more common on people with halo nevi. Atypical moles are thought to have an increased risk of turning cancerous. Removal of a halo nevus is unnecessary.

If the nevus itself has uncharacteristic features, a traditional excision in which the mole part of a halo nevus may be impassive by shave or excision. Halo nevi are considered safe and self-limiting and are not treated. Sunscreen should be applied to all the skin during summer to avert sunburn. The white skin of a halo naevus will burn particularly easily in the sun because it is missing protective melanin pigment.