Leukoedema

The causes are unknown. It is very common in the black population (90% of individuals) and rarer in the white population. It is considered a variation of the normal anatomy of the oral mucosa. Leukoedema is always bilateral and gives the oral mucosa a characteristic wrinkled appearance.

A peculiarity of leukoedema that allows its differential diagnosis is that it disappears when the cheek is stretched outwards and reappears after release (diascopic phenomenon). Leukoedema does not require any treatment.

What is leukoedema

Leukoedema is the anatomic variant of the oral mucosa that has a clinical appearance similar to potentially malignant white lesions such as leukoplakia and lichen planus. Other lesions that closely resemble leukoedema are fluffy white nevus and cheek bite.

Leukoedema is a harmless white lesion of the oral cavity that mimics a premalignant lesion, especially when associated with smoking.

It presents with a diffuse, grayish-white, milky opalescent appearance of the mucosa, usually occurring bilaterally on the buccal mucosa. The surface of the area is folded, creating a wrinkled, white-veined lesion. Apart from the appearance, the lesion is completely asymptomatic.

Causes of leukoedema

Leukoedema is characterized by variable intracellular edema of the superficial half of the epithelium.

The vacuolated cells are large and often have a pyknotic nuclear appearance. They may extend into the basal layer and cluster in inverted wedge-shaped regions separated by normal spinous epithelial cells. Parakeratosis is common, but is not pronounced unless there has been chronic trauma.

Intracellular edema is characteristic of other oral lesions, many of which can be found in the buccal mucosa:

• Keratosis due to tobacco use.
• Frictional keratosis (chronic cheek-bite keratosis).
• White fluffy nevus.
• Witkop's disease.

Identification of etiologic habits will help establish a final diagnosis for tobacco keratosis and friction keratosis.

Microscopically, these usually have a more pronounced superficial keratosis and have chronic inflammatory cells scattered in the underlying stroma.

Since both leukoedema and white fluffy nevus have innocuous beginnings in childhood and adolescence, it may be impossible to distinguish between them, except by clinical "stretch test". By performing this test the nevus will still be visible when the affected mucosa is stretched, whereas leukoedema will disappear.

Although the etiology is unknown, it has been suggested that leukoedema develops in areas of local irritation. All indications are that neither vascular nor hormonal factors are related to the development of leukoedema.

Smoking and chewing tobacco (and cannabis) is a risk factor for the development of the lesion and increases the whiteness and size, most cases are so subtle that they are not even formally diagnosed.

Symptoms of leukoedema

Leukoedema can be easily diagnosed by observing the clinical features. The buccal mucosal stretch test is very helpful in its diagnosis. Some patients may show fine grooves or folds crossing the macula in a lace-like fashion.

This mucosal change may begin as early as 3-5 years of age, but is usually not noticeable until adolescence. By the end of adolescence, 50% of black children have altered mucosa.

The opalescent macule is usually not well demarcated from the surrounding mucosa and is occasionally seen on the soft palate and buccal floor. When the cheeks are stretched outward, the leukoedema usually disappears. This helps to differentiate this lesion from others of similar appearance that could be premalignant, such as leukoplakia.

Treatment of leukoedema

No treatment is necessary for leukoedema. It has no malignant potential, unlike leukoplakia, and does not change significantly after 25-30 years of age of the patient.

If the affected individual stops using tobacco, the lesion is likely to be less pronounced.