White sponge nevus

Overview
White sponge nevus, also known as Cannon's disease or Hereditary leukokeratosis of mucosa, appears to follow a hereditary pattern as an autosomal dominant trait. Although it is congenital in most cases, it can occur in childhood or adolescence.

Pathophysiology
It is caused by a mutation of the keratin 4 and keratin 13 genes.



Presentation
It presents in the mouth, most frequently as a thick bilateral white plaque with a spongy texture, usually on the buccal mucosa, but sometimes on the labial mucosa, alveolar ridge or floor of the mouth. The gingival margin and dorsum of the tongue are almost never affected.

Although this condition is perfectly benign, it is often mistaken for leukoplakia. There is no treatment, but because there are no serious clinical complications, the prognosis is excellent.