Leukoplakia and oral lichen planus (OLP) are common diseases manifesting as white lesions that are considered potentially malignant disorders (PMD). Epithelial dysplasia may be an early sign of potency for the future transformation into oral squamous cell carcinoma (OSCC). A routine biopsy and close observation are recommended for persistent white oral lesions. As frictional keratosis may mimic oral leukoplakia, the question arises:Is there a need for a biopsy of persistent white lesion of traumatic origin?

Material and methods:
Data from 643 oral tissue biopsies were retrospectively analyzed. A total of 176 (27.37%) results with provisional diagnosis of leukoplakia (36 cases), OLP (77 cases) and frictional keratosis (63 cases) were selected. Retrospective data collected included age, gender, smoking status, provisional and histopathological diagnosis. The data was analyzed to assess the prevalence of epithelial dysplasia and OSCC in terms of age, gender and smoking status.

Five (2.84%) cases of OSSC were reported, all of them were graded as G1; four cases of OSCC were found in clinically defined leukoplakia lesions; one case of OSCC (1.3%) was found in OLP biopsy; epithelial dysplasia was reported in 5 lesions (2.84%) provisionally diagnosed as OLP (3 cases), and leukoplakia in 2 cases. No dysplasia or OSCC were found in the lesions diagnosed as frictional keratosis.

Epithelial dysplasia and OSCC may be found in leukoplakia or OLP lesions not initially suspected of any malignancy. In some cases, clinical features are not sufficient to diagnose a lesion without histopathology. Frictional keratosis is easily identified by clinicians, and may not require a biopsy in every case. Clinical and histopathological evaluation of the white lesions still needs improvement

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