The Evolution and Clinical Utility of Oral Epithelial Dysplasia Grading Systems: A Narrative Review

Histological grading of oral epithelial dysplasia (OED) is the gold standard for predicting malignant transformation in potentially malignant disorders. However, traditional grading systems suffer from subjectivity and poor diagnostic reproducibility, complicating patient management. This narrative review evaluates the clinical utility of current and emerging OED grading systems.

We reviewed recent literature (2019-2026) comparing the traditional World Health Organization (WHO) classifications against binary grading, histopathological feature-specific models (two-point and six-point systems), diagnostic biomarkers, and clinical risk factors.

The WHO system frequently demonstrates poor-to-fair interobserver agreement. Conversely, binary and six-point grading systems provide superior reproducibility. While these models effectively stratify malignant transformation risk, their clinical utility is limited by tissue sampling errors, such as "skip areas." Furthermore, immunohistochemical biomarkers (Keratin 13 and 17) show promise as diagnostic adjuncts to assist in identifying high-risk variants like differentiated dysplasia.

While the WHO system remains the gold standard, its subjectivity complicates clinical decisions. Adopting objective binary and feature-specific models offers superior clinical utility for risk stratification. Clear numerical cutoffs alongside expanded morphological features and biomarkers may influence the accuracy of predicting malignant transformation, inform clinical decision-making regarding surgical versus conservative surveillance, and optimize patient management when integrated with clinicopathological findings.