Halo nevi are usually benign. No treatment is necessary if they have a typical appearance, other than reassuring the patient that they are not a concern for skin cancer. The white skin around a halo nevus may be more prone to sunburn, so the use of sunscreen is a good idea to protect the skin. Halo nevi often disappear on their own, but it can take ten years or more.
Plural: halo nevi, halo naeviAlternate Names: halo naevus, halo moles, Grünewald nevus, Sutton naevus, leukoderma acquisita centrifugum, Perinevoid vitiligoPronunciation: HAY-loh NEE-vus • (noun)
Typical Development
The usual progression of development of a halo nevus is that a lighter ring develops around a mole. The mole itself may then become lighter in color and even fade away, leaving only the depigmented circular area. Eventually, over the course of years, the skin regains its usual color in the area.
Causes
A halo nevus appears when the body has an immune response around an existing mole. Why this happens continues to be studied. Immune cells come into the area around the nevus cells and clear out any melanocytes, leaving the area unpigmented. The cells involved are usually T-lymphocytes and some macrophages.
Antibodies to melanoma cells have been found in people with halo nevi, but it isn’t clear whether the antibodies led to the removal of the melanocytes around the mole or whether they formed after the mole cells were disrupted.
Risk of Skin Cancer
Melanoma can rarely occur in a halo nevus, but in those cases, the nevus has atypical features and the depigmented ring is not symmetric. A doctor will check any halo nevus during a skin exam for features that make it suspicious for melanoma, basal cell carcinoma and other conditions that may require treatment.
Because halo nevi can also rarely be a sign of melanoma elsewhere on the body, most dermatologists will recommend a skin exam screening to look for melanoma elsewhere (even though it may be rare).
Generally, a halo nevus does not have to be removed unless it has atypical features. Removing the nevus does not cause the halo portion to get darker. For this reason, removal can cause a noticeable scar in an area of lighter skin color.
History of Halo Nevus
This is a case where art has one of the earliest accurate depictions of a skin lesion, appearing in “The Temptation of St. Anthony,” by Matthias Grünewald, a nightmarish painting that is part of the Isenheim Altarpiece, created from 1512-1516. The lesion was named leukoderma acquisita centrifugum by Sutton in 1916.
