Page 116 - FINAL COMPENDIUM 2020-2021 27.2.2022

THE CLINICAL UTILITY OF CONTEMPORARY ORAL EPITHELIAL DYSPLASIA GRADING
SYSTEMS

Sathasivam HP, Sloan P, Thomson P, Robinson M

Introduction: Clinical management of oral potentially malignant disorders relies on
accurate histopathological assessment of the presence and grade of oral epithelial
dysplasia. While adjunctive laboratory tests have provided useful prognostic information,
none are in widespread clinical use. Objective: To assess the clinical utility of two
contemporary oral epithelial dysplasia grading systems. Materials and methods: Patients
were identified from a clinical database. Oral epithelial dysplasia grading was performed
by three oral and maxillofacial pathologists blinded to clinical outcome using the WHO
2017 system and a binary classification. The primary outcome measure was the
development of oral squamous cell carcinoma, termed ‘malignant transformation’.
Results: One hundred thirty-one cases satisfied the inclusion criteria, of which 23
underwent malignant transformation. There was substantial inter-rater agreement
between the study pathologists for both grading systems, measured using kappa statistics
(κ = 0.753 – 0.784). However, there was only moderate agreement between the
consensus WHO 2017 dysplasia grade for the study against the original grade assigned by
a pool of six pathologists in the context of the clinical service (κ = 0.491). Higher grade
categories correlated with an increased risk of developing cancer using both grading
systems. Conclusion: This study demonstrates that the WHO 2017 and binary grading
systems are reproducible between calibrated pathologists and that consensus reporting
is likely to improve the consistency of grading. The WHO and binary systems were
prognostically comparable. We recommend that institutions implement consensus oral
epithelial dysplasia grading and prospectively audit the effectiveness of risk stratifying
their patients with oral potentially malignant disorders.

Published in J Oral Pathol Med. 2021; 00: 1– 8. doi:10.1111/jop.13262

Dr Hans P Sathasivam Prof. Dr Philip Sloan
Institute for Medical Research Newcastle University Biosciences Institute
National Institutes of Health Newcastle University Centre for Cancer
Ministry of Health Newcastle upon Tyne, UK
Malaysia.
Dr Max Robinson
Prof. Dr Peter Thomson Department of Cellular Pathology
Oral and Maxillofacial Surgery Newcastle University, UK
Faculty of Dentistry, The University of Hong Kong
Hong Kong, Hong Kong SAR

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