Lichenoid dysplasia revisited - evidence from a review of Indian archives.

Abstract

To report on the prevalence of 'lichenoid dysplasia' (LD) in oral mucosal biopsies previously reported as oral lichen planus (OLP), oral lichenoid lesion (OLL) and oral epithelial dysplasia (OED). Based on this case series, to postulate whether features of dysplasia are present in biopsies with a diagnosis of OLP or OLL and vice versa that warrant a separate diagnostic entity of 'lichenoid dysplasia'. This retrospective, multicentre study was carried out by retrieving archival slides of cases diagnosed with OLP, OLL and OED. Diagnostic criteria for the study were based on published guidelines from seminal papers. A total of 165 cases, 70 OLP and OLL and 95 epithelial dysplasia cases, were re-examined. The diagnosis of OLPs and OLLs was first reconfirmed according to published diagnostic criteria. They were then verified for microscopic features of epithelial dysplasia. Among cases of leukoplakia diagnosed with epithelial dysplasia, we further verified for the presence of lichenoid features. A total of 70 cases of OLP and OLL were microscopically evaluated (OLP-54; OLL-16). Epithelial dysplasia was noted in 11 cases (OLP - 8 of 54; OLL - 3 of 16). Nineteen cases of OLP (19 of 54) were found to bear features of OLLs as per published diagnostic criteria. Among the OED group, 22 of the 95 cases showed lichenoid features. The study confirms lichenoid features may be found in OEDs and epithelial dysplasia may be found in OLP/OLL. We reconfirm that these microscopic features may coexist. Our findings require further discussion by a panel of experts to redefine the entity known as 'lichenoid dysplasia'. Future studies should address the concept of lichenoid dysplasia that may assist to resolve any controversies with regard to the malignant potential of OLP.