Clinicopathological Evaluation of Oral Leukoplakia: A Single-Center Study of 676 Cases in Japan

Objectives To analyze the clinical and histopathological characteristics of oral leukoplakia (OL) in the Japanese population and investigate the prevalence and risk factors for epithelial dysplasia (ED) and carcinoma within lesions. Study Design Data, including age, sex, lesion site, and histopathological features, of 676 cases diagnosed with OL over the previous 10 years were analyzed. Dysplasia and carcinoma prevalence were determined. Results In male patients, the most affected site was the gingiva (42.7%), whereas in females, it was the tongue (47.6%). Moreover, ED was more prevalent in males (41.9%), whereas epithelial hyperplasia was more common in females (44.7%). A significant difference was observed between affected sites with regard to the presence of dysplasia. The ED rates by site were 64.6% and 33.7% for the tongue and gingiva, respectively (P<0.05). The squamous cell carcinoma rates by site were 23.4%, 5.4 %, and 3.4% for the tongue, buccal mucosa, and gingiva, respectively (P<0.05). Logistic regression analysis revealed a higher prevalence of dysplasia in males than it did in females and that the risk for both dysplasia and carcinoma was highest in the tongue. Conclusions Dysplasia is common in OL cases, often showing carcinoma. Early biopsy and interventions are key in OL management.