Oral leukoplakia

What is oral leukoplakia?

Oral leukoplakia describes a white patch or plaque of the oral mucosa that cannot be characterised clinically or pathologically as any other disease.

What causes oral leukoplakia?

Oral leukoplakia may later prove to be due to one of the following conditions:

• Carcinoma in situ of the oral cavity (intraepithelial carcinoma) 
• Nicotine stomatitis
• Candidiasis
• Oral lichen planus
• Frictional keratoses
• Habitual cheek or lip biting
• Lupus erythematosus.

In children, the differential diagnosis includes dyskeratosis congenita and hidrotic ectodermal dysplasia. 

Who gets oral leukoplakia?

There is a strong association with tobacco smoking (leukoplakia is six times more common in smokers than non-smokers) and alcohol intake (independent of drinking pattern or beverage type). It is also associated with betel quid chewing and oral submucous fibrosis. 

How is the diagnosis made?

• Biopsy of clinically suspected oral leukoplakia is mandatory to: exclude recognised diseases, and to assess for the absence or presence and grade of dysplasia.
• It is appropriate to wait two weeks after the first presentation to assess clinical response to initial treatment, e.g. for candida, change in tooth brushing habit, cessation of smoking, etc
• The biopsy may be incisional or excisional, single or multiple and may be done under local or general anaesthetic depending on site, the number of biopsies required and type of biopsy.
• Biopsies should be taken from either a symptomatic area or if asymptomatic then from red or indurated areas.
• The presence of dysplasia, carcinoma-in-situ and invasive carcinoma cannot always be predicted clinically.

The histopathology of oral leukoplakia is not always diagnostic. Epithelial changes range from atrophy (thinned) to hyperplasia (thickened), and it may show hyperkeratosis. Dysplasia (atypical changes) may be mild, moderate, severe, carcinoma in situ or invasive carcinoma. The pathology report must comment on the absence or presence of dysplasia and the severity.

What is the treatment of oral leukoplakia?

The treatment of oral leukoplakia depends on its cause.