COMMON LESIONS OF THE ORAL CAVITY

oralcavitykapak

ORAL LEUKOPLAKIA

Gülsüm Akkaya

Adıyaman University, Faculty of Dentistry, Department of Oral and Maxillofacial Radiology, Adıyaman, Türkiye

Akkaya G. Oral Leukoplakia. In: Çakır B editor. Common Lesions of the Oral Cavity. 1st ed. Ankara: Türkiye Klinikleri; 2025. p.31-39.

ABSTRACT

Oral leukoplakia (OL) is a condition characterized by white plaques observed in the oral mucosa that cannot be clinically or histopathologically associated with any disease and carry a risk of malignancy. It has a prevalence of 0.1% to 5% in the population and is observed equally in both genders. OL is most commonly seen in individuals over the age of 40 and is associated with risk factors such as smoking, alcohol consumption, betel nut chewing dietary habits, human papillomavirus (HPV) types 16 and 18, and genetic predisposition.

OL appears as homogeneous or non-homogeneous plaques that cannot be removed by scraping. Ho- mogeneous lesions, which constitute the majority of cases, are typically thin and smooth. In contrast, non-homogeneous lesions (e.g., speckled or verrucous types) have a higher risk of malignancy. Lesions are commonly found on the cheeks, lips, and floor of the mouth, but they can also occur on the dorsal surface of the tongue and the palate. Lesions on the tongue and the floor of the mouth are more prone to malignant transformation.

The white appearance of OL results from structural changes in the epithelial tissue, including increased keratin production (hyperkeratosis), epithelial thickening, and reduced visibility of underlying blood vessels. These changes enhance light reflection, giving the lesions their characteristic white color.

Histopathological evaluation is critical for assessing the malignancy risk of OL. Lesions are classified into low- and high-risk groups based on the presence of epithelial dysplasia. High-risk lesions and proliferative verrucous leukoplakia (PVL) have a greater likelihood of malignant transformation. Ad- vanced diagnostic methods, including biomarker analysis and non-invasive imaging techniques, can be used to more effectively evaluate transformation risks.

Treatment primarily involves addressing causative factors. For advanced lesions, surgical excision, cryotherapy, laser ablation, or other non-invasive methods are preferred. Antiviral or immunomodula- tory treatments may be applied for HPV-related cases. Although chemoprevention shows promise, it remains controversial due to concerns over balancing efficacy and toxicity.

Early diagnosis, regular follow-up, and advancements in diagnostic and therapeutic approaches are crucial for reducing the malignant potential of OL and improving prognosis. Lifelong follow-up is essential for cases with a high risk of malignancy.

Keywords: Mouth diseases; Leukoplakia; Oral leukoplakia; Squamous cell carcinoma; Differential diagnosis

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