Leukoplakia is a white patch on the tongue mucosa, classified into benign white keratosis and premalignant leukoplakia based on its tendency to become malignant. The causes are as follows: white keratosis is mostly caused by external factors, primarily local mechanical, chemical, physical, and inflammatory stimuli. Premalignant leukoplakia is mainly due to intrinsic individual predispositions, which vary from person to person. Under the same conditions, some individuals are more prone to cancer. This intrinsic predisposition is associated with genetics, immunosuppression, immunodeficiency, and nutritional deficiencies such as vitamins A and E.

bubble_chart Pathological Changes

Histopathological changes of leukoplakia:

1. Epithelial simple hyperplasia refers to hyperkeratosis or parakeratosis of the surface epithelium. The granular layer is prominent, the spinous layer cells proliferate, and the epithelial rete ridges are enlarged. The connective tissue exhibits varying degrees of inflammatory cell infiltration. There is no tendency for malignant transformation, and the leukoplakia gradually thins and disappears after the removal of stimulating factors. Homogeneous leukoplakia belongs to this type of pathological change.
2. Epithelial dysplasia involves marked proliferation of the epithelium, accompanied by abnormal keratinization and atypical hyperplasia of epithelial cells, or even malignant transformation, such as changes in the polarity of basal cells. The epithelial stratification is irregular, with disordered arrangement, increased mitosis, hyperchromatic nuclei, nuclear condensation, and enlarged nucleoli. Dysplastic epithelium confined within the epidermis with an intact basement membrane can be considered carcinoma in situ, while involvement and breach of the basement membrane indicate early invasive carcinoma. Verrucous, granular, and erosive types all have a tendency for malignant transformation and require special attention during follow-up observation.

bubble_chart Clinical Manifestations

Leukoplakia on the tongue often occurs on the dorsal, ventral, or lateral surfaces of the tongue. The white patches have clear boundaries and are slightly raised above the mucosal surface, appearing milky white, grayish-white, or slightly yellowish. The lesions may have a rough or granular surface, verrucous projections, or erosions. Some reddened areas may also be scattered within the white patches.

Based on clinical manifestations, leukoplakia can be divided into four types:

1. Homogeneous leukoplakia: The lesion appears as a white patch, slightly elevated above the mucosal surface, with a somewhat rough, wrinkled-paper-like texture. It may be asymptomatic or cause a dry, rough sensation.
2. Verrucous proliferation: The white patch is thick and raised, with a verrucous surface that feels hard and rough.
3. Granular type: Small, raised white granular keratotic changes are present on a reddened mucosal surface, resembling villi.
4. Erosive type: The white patch exhibits erosions, possibly with ulcer formation, accompanied by significant pain.

bubble_chart Treatment Measures

1. Simple epithelial hyperplasia or simple leukokeratosis should involve the removal of all local irritants, and smokers should quit smoking.
2. For leukoplakia suspected of malignant transformation, such as verrucous, granular, or erosive sexually transmitted disease changes, surgical excision, cryotherapy, or CO₂ laser therapy should be performed. Patients who have undergone treatment should be regularly followed up to detect and treat any recurrence early.
3. Topical application of 0.3% tretinoin ointment for one to several weeks can lead to the regression of leukoplakia. Tretinoin inhibits epithelial keratinization. After discontinuation, the regressed lesions may recur, but tretinoin remains effective upon reuse.
4. Vitamin A and Vitamin E: Vitamin A maintains the integrity and health of epithelial tissue structure, and some believe it plays a role in preventing epithelial malignant transformation. Vitamin E has a beneficial effect on body metabolism and possesses strong antioxidant properties, which can prevent the oxidation of Vitamin A and facilitate its absorption. Vitamin A is taken orally at 250,000 U three times daily, and Vitamin E at 50 mg three times daily.