Correlation between WHO and Modified WHO Classification Systems in the Histopathologic Diagnosis of Oral Lichen...

Area of Science:

• Oral pathology
• Autoimmune diseases
• Histopathology

Background:

• Oral lichen planus (OLP) is a common chronic autoimmune condition.
• Accurate histopathological classification is crucial for OLP diagnosis and management.
• Existing WHO and modified WHO (Mod.WHO) classification systems require comparative analysis.

Purpose of the Study:

• To correlate the histopathological criteria of the WHO and Mod.WHO classification systems for OLP.
• To evaluate the intraobserver and interobserver reliability of these classification systems.
• To determine the diagnostic utility of each system in identifying OLP lesions.

Main Methods:

• A cross-sectional study involving 64 OLP lesion slides.
• Individual (intraobserver) and group (interobserver) histopathological evaluation by three pathologists.
• Comparison of WHO and Mod.WHO criteria using Cohen's kappa coefficient (κ) for statistical analysis.

Main Results:

• The Mod.WHO method identified significantly more OLP cases (41) than the WHO method (8).
• Intraobserver reproducibility was generally low (κ values ranging from 0.062 to 0.181).
• Interobserver reproducibility was also poor (κ = 0.148), indicating no significant correlation between the systems. WHO criteria were more sensitive, while Mod.WHO criteria were more specific.

Conclusions:

• The Mod.WHO classification demonstrates higher specificity for histopathological diagnosis of OLP.
• Mod.WHO criteria appear more valuable for OLP diagnosis, particularly when integrated with clinical findings.
• Further refinement or standardized application of Mod.WHO criteria may enhance diagnostic accuracy.