Leukoplakia remains one of the most frequently encountered precancerous lesions in dental practice and oral medicine. Although many lesions remain benign, a considerable proportion may undergo malignant transformation into oral squamous cell carcinoma. Conventional clinical examination provides limited information regarding the biological behavior of the lesion. Histopathological evaluation of epithelial dysplasia remains the gold standard for diagnosis; however, it does not always accurately predict disease progression. Recent advances in molecular pathology have identified several biomarkers associated with cell proliferation, apoptosis, genetic instability, and tumor development. The integration of molecular and morphological assessment may improve risk stratification, guide clinical management, and contribute to the prevention of oral cancer.
The aim of this study was to investigate the diagnostic and prognostic value of molecular and morphological markers in oral leukoplakia and to assess their usefulness in predicting destructive and proliferative changes of the oral mucosa that may precede malignant transformation.
The study included 70 patients diagnosed with oral leukoplakia and 25 healthy individuals serving as controls. Clinical examination and biopsy specimens were obtained from all patients. Histopathological evaluation was performed to determine the degree of epithelial hyperkeratosis, acanthosis, cellular atypia, and epithelial dysplasia. Immunohistochemical analysis was conducted using biomarkers associated with cell proliferation and carcinogenesis, including Ki-67, p53, Cyclin D1, Bcl-2, and E-cadherin. Statistical analysis was used to assess correlations between molecular marker expression and morphological alterations observed in tissue samples.
Histological examination demonstrated varying degrees of epithelial dysplasia among patients with leukoplakia. Increased expression of Ki-67 and Cyclin D1 was observed in lesions exhibiting pronounced proliferative activity. Elevated p53 expression was associated with genetic instability and increased risk of malignant transformation. Reduced E-cadherin expression indicated disruption of epithelial cell adhesion and greater invasive potential. Increased Bcl-2 activity suggested suppression of programmed cell death in advanced lesions. Significant correlations were identified between the severity of dysplastic changes and molecular marker expression levels. Combined evaluation of molecular and morphological criteria improved the sensitivity and specificity of early diagnosis compared with routine histopathological examination alone.
Molecular and morphological markers are valuable tools for the diagnosis and prediction of oral mucosal changes in leukoplakia. The combined assessment of histopathological features and molecular biomarkers allows more accurate identification of high-risk lesions and improves the prediction of malignant transformation. Incorporating these markers into routine diagnostic protocols may contribute to earlier intervention, individualized treatment planning, and improved prevention of oral squamous cell carcinoma.
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