Malignant Transformation of Oral Leukoplakia in a Well-Defined Cohort of 162 Patients With a Long-Term Follow-Up

Objectives: oral leukoplakia is a potentially malignant disorder of the oral mucosa. The aim of this retrospective study was to find possible factors that predict malignant transformation of oral leukoplakia in a well-defined cohort of patients with long-term follow-up. All oral leukoplakia were staged according to a clinicopathological classification and staging system.

Methods: this study consisted of 162 patients. The size, presence and degree of epithelial dysplasia were noted according to the oral leukoplakia staging system. Initial management consisted of observation, surgical excision or CO2 laser vaporization. The mean follow-up was 64.8 months (SD=49.4 range 12-219 months).

Results: in 27/162 patients (16.7%) malignant transformation occurred between 15 and 187 months (mean 67.9 months) after the first visit, therefore the annual malignant transformation rate was 3.1%. A stage IV lesion (p=0.004), the presence of dysplasia (p=0.017) and non-homogenous oral leukoplakia (p=0.001) showed to be statistically significant predictors of malignant transformation.

Conclusion: a stage IV lesion, the presence of dysplasia and non-homogenous oral leukoplakia showed to be significant predictors of malignant transformation of oral leukoplakia.