Histologic lichenoid features in oral dysplasia and squamous cell carcinoma

Oral epithelial dysplasia with lymphocytic immune response: clinicopathological characterisation of 44 cases

AIMS

Oral epithelial dysplasia (OED) often exhibits a lymphocytic/lichenoid immune response (LIR), imparting histological resemblance to lichenoid mucositis and rendering diagnosis challenging. The clinical appearances of OED and lichenoid inflammatory processes are generally divergent, presenting as well-demarcated hyperkeratotic plaques and diffuse white and/or red mucosal change with variably prominent Wickham striae, respectively. To date, clinicopathological characterisation of OED with LIR, including clinical/gross appearance, has not been depicted.

METHODS AND RESULTS

Cases of solitary OED with LIR for which a clinical photograph was available were identified in the authors' institutional files. Clinical and histological features were documented. In 44 identified cases, dysplasia was mild (19 of 44, 43.2%), moderate (19 of 44, 43.2%) and severe (six of 44, 13.6%). Clinically/grossly, all 44 cases (100.0%), presented as well-demarcated hyperkeratotic plaques lacking diffuse white-and-red mucosal change or Wickham striae. Histologically, OED with LIR exhibited numerous 'lichenoid' features beyond the lymphocytic band in the superficial lamina propria, including: leucocyte transmigration (38 of 44, 86.4%), spongiosis (37 of 44, 84.1%), Civatte/colloid bodies (36 of 44, 81.8%), basal cell degeneration (29 of 45, 65.9%), sawtooth rete ridges (11 of 44, 25.0%) and subepithelial clefting (7 of 44, 15.9%).

CONCLUSIONS

Virtually any lichenoid histological feature may be seen in OED with LIR, representing a significant diagnostic pitfall. The typical clinical appearance of OED with LIR is of a well-demarcated hyperkeratotic plaque, characteristic of keratinising dysplasia and devoid of lichenoid features. This suggests that pathologist access to clinical photographs during diagnostic interpretation of biopsied white lesions, which represents opportunity to perform gross examination of the disease process, may reduce interobserver variability and improve diagnostic accuracy in this challenging differential diagnosis.

Immunophenotypic and Gene Expression Analyses of the Inflammatory Microenvironment in High-Grade Oral Epithelial Dysplasia and Oral Lichen Planus

BACKGROUND

Oral lichen planus (OLP) and oral epithelial dysplasia (OED) present diagnostic challenges due to clinical and histologic overlap. This study explores the immune microenvironment in OED, hypothesizing that immune signatures could aid in diagnostic differentiation and predict malignant transformation.

METHODS

Tissue samples from OED and OLP cases were analyzed using immunofluorescence/immunohistochemistry (IF/IHC) for CD4, CD8, CD163/STAT1, and PD-1/PDL-1 expression. RNA-sequencing was performed on the samples, and data was subjected to CIBERSORTx analysis for immune cell composition. Gene Ontology analysis on the immune differentially expressed genes was also conducted.

RESULTS

In OED, CD8 + T-cells infiltrated dysplastic epithelium, correlating with dysplasia severity. CD4 + lymphocytes increased in the basal layer. STAT1/CD163 + macrophages correlated with CD4 + intraepithelial distribution. PD-1/PDL-1 expression varied. IF/IHC analysis revealed differential immune cell composition between OED and OLP. RNA-sequencing identified upregulated genes associated with cytotoxic response and immunosurveillance in OED. Downregulated genes were linked to signaling, immune cell recruitment, and tumor suppression.

CONCLUSIONS

The immune microenvironment distinguishes OED and OLP, suggesting diagnostic potential. Upregulated genes indicate cytotoxic immune response in OED. Downregulation of TRADD, CX3CL1, and ILI24 implies dysregulation in TNFR1 signaling, immune recruitment, and tumor suppression. This study contributes to the foundation for understanding immune interactions in OED and OLP, offering insights into future objective diagnostic avenues.

Demystifying oral epithelial dysplasia: a histological guide

Oral epithelial dysplasia is a histologically diagnosed potentially premalignant disorder of the oral mucosa, which carries a risk of malignant transformation to squamous cell carcinoma. The diagnosis and grading of oral epithelial dysplasia is challenging, with cases often referred to specialist oral and maxillofacial pathology centres for second opinion. Even still there is poor inter-examiner and intra-examiner agreement in a diagnosis. There are a total of 28 features of oral epithelial dysplasia listed in the 5th edition of World Health Organization classification of tumours of the head and neck. Each of these features is poorly defined and subjective in its interpretation. Moreover, how these features contribute to dysplasia grading and risk stratification is even less well defined. This article discusses each of the features of oral epithelial dysplasia with examples and provides an overview of the common mimics, including the normal histological features of the oral mucosa which may mimic atypia. This article also highlights the paucity of evidence defining these features while offering suggested definitions. Ideally, these definitions will be refined, and the most important features identified to simplify the diagnosis of oral epithelial dysplasia. Digital whole slide images of the figures in this paper can be found at: https://www.pathogenesis.co.uk/r/demystifying-dysplasia-histology-dataset.

Clinicohistological Characteristics of Patients with Oral Lichenoid Mucositis: A Retrospective Study for Dental Hospital Records

Oral lichenoid mucositis (OLM) of the oral mucosa is a histological diagnosis mainly characterised by a band of inflammatory infiltrate in lamina propria and basal cell degeneration. These features describe oral lichen planus or oral lichenoid reaction. However, it could be seen in oral dysplasia. The study aimed to assess the demographics and clinicohistological characteristics of patients with OLM and their relevance to dysplastic changes in the oral mucosa. This was a cross-sectional and retrospective study of archived and electronic records of individuals with histological confirmation of OLM at King Saud University Medical City, Saudi Arabia. The descriptive and correlation assessments were used to describe the demographics and clinicohistological characteristics and their associations, respectively [p < 0.05]. The analysis included 140 records of patients with histological confirmation of OLM with a mean age of 47 (±13), and 57% (n = 81) were females. Notably, 40% of patients had at least one medical condition, mainly diabetes mellitus, 74% were asymptomatic, and 52% had lesions in the buccal mucosa. Dysplasia was seen in 18 (12%) of the 140 reviewed records. Regarding the associations between study variables, dysplastic changes were associated with the male gender [p = 0.024] and were of no significance with increased age [p = 0.594]. Moreover, having oral symptoms was associated with older age [p < 0.001], medical history of diabetes [p = 0.0132] and hypertension [p < 0.001]. The present study findings could help indicate the individuals with histologically confirmed OLM who suffer the most from the clinical disease and have an increased risk of dysplastic changes. Therefore, symptomatic management and long-term follow-up can be planned accordingly.

Direct immunofluorescence cannot be used solely to differentiate among oral lichen planus, oral lichenoid lesion, and oral epithelial dysplasia

Background/purpose

Some red and white lesions may have similar manifestations, making them difficult to be diagnosed. A direct immunofluorescence (DIF) assay can assist in making a final diagnosis of oral lichen planus (OLP). The aim of this study was to evaluate and compare the DIF profile in patients who had the clinical presentations of OLP and were histopathologically diagnosed with OLP, OLL (oral lichenoid lesion), or OED (oral epithelial dysplasia).

Materials and methods

The data were obtained from the medical records of 136 patients with the clinical presentations of OLP. Demographic information, histopathological diagnosis, malignant transformation, and DIF results were collected and analyzed.

Results

In this study, 117 patients (86.0%) were DIF-positive, while 19 patients (14.0%) were DIF-negative. The highest DIF-positivity rate was in the OLP group (88.9%) followed by the OLL (83.7%), and the OED groups (81%). There were no significant differences in DIF-positivity rate, type of immunoreactants, location, or interpretation among these groups. Shaggy fibrinogen at the basement membrane zone (BMZ) was the most common DIF pattern in all groups.

Conclusion

The DIF assay alone cannot be regarded as sufficient evidence for OLP, OLL, and OED differentiation. A histopathological examination is required to determine the presence of epithelial dysplasia or malignancy. To diagnose dysplastic lesions with the clinical manifestations of OLP, careful clinicopathologic correlation is mandatory. Due to the lack of scientific evidence to identify the primary pathology and the ongoing malignancy risk of epithelial dysplasia, meticulous long-term follow-up plays a crucial role in patient management.

A digital score of peri-epithelial lymphocytic activity predicts malignant transformation in oral epithelial dysplasia

Oral squamous cell carcinoma (OSCC) is amongst the most common cancers, with more than 377,000 new cases worldwide each year. OSCC prognosis remains poor, related to cancer presentation at a late stage, indicating the need for early detection to improve patient prognosis. OSCC is often preceded by a premalignant state known as oral epithelial dysplasia (OED), which is diagnosed and graded using subjective histological criteria leading to variability and prognostic unreliability. In this work, we propose a deep learning approach for the development of prognostic models for malignant transformation and their association with clinical outcomes in histology whole slide images (WSIs) of OED tissue sections. We train a weakly supervised method on OED cases (n = 137) with malignant transformation (n = 50) and mean malignant transformation time of 6.51 years (±5.35 SD). Stratified five-fold cross-validation achieved an average area under the receiver-operator characteristic curve (AUROC) of 0.78 for predicting malignant transformation in OED. Hotspot analysis revealed various features of nuclei in the epithelium and peri-epithelial tissue to be significant prognostic factors for malignant transformation, including the count of peri-epithelial lymphocytes (PELs) (p < 0.05), epithelial layer nuclei count (NC) (p < 0.05), and basal layer NC (p < 0.05). Progression-free survival (PFS) using the epithelial layer NC (p < 0.05, C-index = 0.73), basal layer NC (p < 0.05, C-index = 0.70), and PELs count (p < 0.05, C-index = 0.73) all showed association of these features with a high risk of malignant transformation in our univariate analysis. Our work shows the application of deep learning for the prognostication and prediction of PFS of OED for the first time and offers potential to aid patient management. Further evaluation and testing on multi-centre data is required for validation and translation to clinical practice. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Histopathological findings of oral epithelial dysplasias and their relation to malignant transformation

OBJECTIVES

Oral squamous cell carcinomas (OSCCs) are often diagnosed late. This study aimed to determine how frequently oral epithelial dysplasia (OED) transforms to OSCC and to identify histological features that could influence the rate of malignant transformation.

MATERIALS AND METHODS

The study was a retrospective analysis of OED over 29 years at the Institute of Dentistry, University of Turku, Finland. OEDs with co-existing carcinomas were excluded from the data (5.8%). OED patients who developed carcinoma were identified from the Finnish Cancer Registry database.

RESULTS

Altogether 681 OED patients had a mean age of 59.0 years, and the male:female ratio was 0.67. Of all OED samples, 21.8% were on the tongue, followed by lining mucosa (21.3%), lip (5.3%), and masticatory mucosa (4.85%). In addition, 46.7% had no location cited. The prevalence of mild dysplasia was 62.4%, moderate dysplasia 29.1%, and severe dysplasia 3.2%. Of the patients, 94.7% had an additional histological diagnosis alongside OED. Candidiasis, lichenoid inflammation, and ulcer were found in 18.2%, 0.0%, and 22.7% of severe dysplasias, in 12.1%, 12.2%, and 22.7% of moderate dysplasias, and in 6.6%, 12.2%, and 15.8% of mild dysplasias, respectively. An additional histopathological diagnosis did not increase the risk for OED to transform to OSCC. In a mean time of 5.2 (range 0.7-29.0) years, 7.5% of OED patients developed OSCC.

CONCLUSIONS

Location on the tongue and the more severe OED grades increased the risk of malignant transformation of OED. These patients may benefit from an intensified follow-up schedule to ensure early diagnosis of OSCC.

Characterization of initial/early histologic features of proliferative leukoplakia and correlation with malignant transformation: a multicenter study

The aim of this multicenter retrospective study is to characterize the histopathologic features of initial/early biopsies of proliferative leukoplakia (PL; also known as proliferative verrucous leukoplakia), and to analyze the correlation between histopathologic features and malignant transformation (MT). Patients with a clinical diagnosis of PL who have at least one biopsy and one follow-up visit were included in this study. Initial/early biopsy specimens were reviewed. The biopsies were evaluated for the presence of squamous cell carcinoma (SCCa), oral epithelial dysplasia (OED), and atypical verrucous hyperplasia (AVH). Cases that lacked unequivocal features of dysplasia were termed "hyperkeratosis/parakeratosis not reactive (HkNR)". Pearson chi-square test and Wilcoxon test were used for statistical analysis. There were 86 early/initial biopsies from 59 patients; 74.6% were females. Most of the cases had a smooth/homogenous (34.8%) or fissured appearance (32.6%), and only 13.0% had a verrucous appearance. The most common biopsy site was the gingiva/alveolar mucosa (40.8%) and buccal mucosa (25.0%). The most common histologic diagnosis was OED (53.5%) followed by HkNR (31.4%). Of note, two-thirds of HkNR cases showed only hyperkeratosis and epithelial atrophy. A lymphocytic band was seen in 34.8% of OED cases and 29.6% of HkNR cases, mostly associated with epithelial atrophy. Twenty-eight patients (47.5%) developed carcinoma and 28.9% of early/initial biopsy sites underwent MT. The mortality rate was 11.9%. Our findings show that one-third of cases of PL do not show OED with most exhibiting hyperkeratosis and epithelial atrophy, but MT nevertheless occurred at such sites in 3.7% of cases.

Oral Epithelial Dysplasia: A Review of Diagnostic Criteria for Anatomic Pathologists

Oral epithelial dysplasia (OED) represents a spectrum of histologic changes in the oral cavity mucosa that has the potential to transform into oral squamous cell carcinoma. Predicting the risk of malignant transformation is predominantly based on clinicopathologic correlation, histologic examination and grading. OED often poses a diagnostic challenge, primarily due to its histologic mimics and a large number of terminologies used in the literature. The grading system for OED is also fraught with significant interobserver variability. This review summarizes the essential clinical and histopathologic features of OED and its mimics. Practical preanalytical, analytical, and postanalytical considerations for anatomic pathologists are discussed to improve the diagnostic accuracy and increase the reproducibility in the grading of OED.

Oral epithelial dysplasia: Recognition, grading and clinical significance

Histopathological grading of epithelial dysplasia remains the principal laboratory method for assessing the risk of malignant transformation in oral potentially malignant disorders (OPMDs). Current views on the molecular pathogenesis and histological interpretation of the features of epithelial dysplasia are described, and the use of grading systems for epithelial dysplasia is discussed. Changes to the current 2017 WHO criteria for diagnosis are proposed with emphasis on the architectural features of epithelial dysplasia. The predictive values of three-grade and binary systems are summarised, and categories of epithelial dysplasia are reviewed, including lichenoid and verrucous lesions, keratosis of unknown significance, HPV-associated dysplasia, differentiated and basaloid epithelial dysplasia. The implications of finding epithelial dysplasia in an oral biopsy for clinical management are discussed from the pathologists' viewpoint.

Dysplasia in oral lichen planus: relevance, controversies and challenges. A position paper

Background

Patients with oral lichen planus (OLP) have an increased risk of oral cancer. For this reason, OLP is classified as an oral potentially malignant disorder. However, the precise personal (or individual) risk is unknown. Recent meta-analytical studies have reported that dysplastic OLP may transform to cancer in around 6% of cases, while the rate of transformation is lower (<1.5%) in non-dysplastic cases. The presence of epithelial dysplasia has emerged as the most powerful indicator for assessing cancer risk in oral potentially malignant disorders in routine practice. However, the general acceptance of epithelial dysplasia as an accompanying histologic feature in OLP is subject to great controversy. Many pathologists consider the presence of dysplasia as a criterion to exclude OLP when routinely reporting on this disease. This practice, widespread among oral pathology professionals, has resulted in the underestimation of the potential for malignancy of OLP.

Material and Methods

A review of the literature was carried out in order to critically analyze the relevance, controversies and challenges encountered across the diagnosis of epithelial dysplasia in OLP.

Results

12 studies have been published examining dysplastic changes in OLP, reporting Figures ranging from 0.54% to 25% of cases with dysplasia in the first diagnostic biopsy. The diagnosis of dysplasia in the OLP poses an additional difficulty due to the fact that the affected oral epithelium per se develops changes related to autoimmune aggression. Among the most frequent histological features of OLP that develops dysplasia are basal cell hyperplasia with basaloid appearance, loss of basal cells polarity, cellular and nuclear pleomorphism and irregular stratification.

Conclusions

Epithelial dysplasia should not be considered an exclusion criterion for OLP; its evaluation requires experienced pathologists in this field.

Key words:Oral lichen planus, epithelial dysplasia, oral cancer.

Gingival Leukoplakia: Hyperkeratosis with Epithelial Atrophy Is A Frequent Histopathologic Finding

White lesions on the gingiva and palatal mucosa may represent reactive keratoses, including specific diseases such as benign alveolar ridge keratosis, or nonreactive keratoses, such as true leukoplakia, the latter being associated with a high recurrence rate at this site. The aim of this study is to determine the histopathologic features of gingival keratoses. Hyperkeratotic lesions from the gingiva, palatal mucosa, and alveolar ridge mucosa were available for evaluation after excluding specific keratotic lesions such as candidiasis. There were 321 biopsies from 296 patients and approximately half of the cases (159/321, 49.5%) were reactive keratoses. The rest of the 162 biopsies from 149 patients (76 females; 51.0%) represented true leukoaplakias. The most common location was the gingiva (73.2%) followed by the palatal mucosa (17.0%). Hyperkeratosis/parakeratosis not reactive (HkNR) represented 43.8% of cases; 45.7% were dysplasia or carcinoma, and the rest were not readily classifiable as reactive or non-reactive keratoses. Histopathologic features commonly noted in the HkNR lesions include sharp demarcation (72.7%), corrugated surface (53.5%), and epithelial atrophy (48.1%). A lymphocytic band was noted in 8.5% of the cases, mostly associated with epithelial atrophy (5/6 cases). Seven patients with 17 biopsies from noncontiguous sites likely had proliferative leukoplakia; the most common location was the gingiva (88.2%) and the most common diagnosis was HkNR (52.9%). HkNR is a common histopathologic diagnosis for leukoplakias on the gingiva, and these lesions frequently exhibit thick hyperkeratosis, epithelial atrophy and a lymphocytic band at the interface.

Observer agreement in the diagnosis of oral lichen planus using the proposed criteria of the American Academy of Oral and Maxillofacial Pathology

BACKGROUND

Oral lichen planus (OLP) is a common chronic inflammatory condition with an undefined malignant transformation potential. There have been many attempts at providing a specific definition of OLP without conclusive outcomes. A new set of diagnostic criteria was proposed in 2016 by the American Academy of Oral and Maxillofacial Pathology (AAOMP) in an endeavour to resolve this issue, and this has not yet been evaluated. This study aimed to assess the utility of AAOMP proposed criteria for the diagnosis of OLP.

METHODS

Five pathologists blindly assessed a cohort of 215 digital whole slide images (WSI) obtained from haematoxylin and eosin-stained microscopic slides. Forty-six WSI were included twice to assess the intra-observer agreement. Included cases were diagnosed clinically as either OLP or oral lichenoid reaction. Each pathologist was asked to utilize the AAOMP histopathological criteria while assessing slides. The variations in diagnoses were assessed by unweighted kappa statistics.

RESULTS

The level of intra-observer agreement was very good (0.801 to 0.899). The level of inter-observer agreement among the observers varied from good (0.658) to very good (0.842) when the responses were categorized as evident/compatible OLP versus no OLP and was good (0.62 to 0.725) when the responses were categorized as evident OLP, versus compatible OLP, versus no OLP. The clinico-pathological correlation was 87.6%.

CONCLUSION

A reliable level of agreement can be achieved by pathologists for the diagnosis of OLP using the AAOMP criteria for differentiation between lichenoid and other conditions. There are still limitations in discriminating OLP from oral lichenoid lesions microscopically.

Oral Potentially Malignant Disorders (OPMD): What is the clinical utility of dysplasia grade?

INTRODUCTION

Oral epithelial dysplasia is considered a potential histologic precursor of subsequent squamous cell cancer. As standard clinical practice, pathologists grade dysplasia to assess risk for progression to malignancy. Except for the most advanced grade, severe dysplasia, dysplasia grading has failed to correlate well with the risk to develop invasive cancer. The questions of what process dysplasia grading best represents and what clinical utility dysplasia grading may have are explored.

AREAS COVERED

This narrative review is based on PubMed search with emphasis on papers since 2010. Epithelial dysplasia as a precursor lesion of cancer and dysplasia grading as a risk assessment tool for progression to cancer are discussed. The close clinical association of dysplasia with known carcinogens, alcohol, and tobacco products is presented.

EXPERT OPINION

Oral epithelial dysplasia is often, associated with prolonged exposure to tobacco and alcohol products. With reduction of carcinogen exposure, dysplasia is known to regress in some cases. It is proposed that histologic dysplasia grade together with macroscopic images of dysplastic clinical lesions be used as an educational tool to incentivize patients to reduce their known carcinogen exposure. This strategy has the potential to reduce lesion progression thereby reducing the disease burden of oral cancer.

Proliferative Verrucous Leukoplakia: An Expert Consensus Guideline for Standardized Assessment and Reporting

The many diverse terms used to describe the wide spectrum of changes seen in proliferative verrucous leukoplakia (PVL) have resulted in disparate clinical management. The objective of this study was to produce an expert consensus guideline for standardized assessment and reporting by pathologists diagnosing PVL related lesions. 299 biopsies from 84 PVL patients from six institutions were selected from patients who had multifocal oral leukoplakic lesions identified over several years (a minimum follow-up period of 36 months). The lesions demonstrated the spectrum of histologic features described in PVL, and in some cases, patients developed oral cavity squamous cell carcinoma (SCC). An expert working group of oral and maxillofacial and head and neck pathologists reviewed microscopic features in a rigorous fashion, in combination with review of clinical photographs when available. The working group then selected 43 single slide biopsy cases for whole slide digital imaging (WSI) review by members of the consensus conference. The digital images were then reviewed in two surveys separated by a washout period of at least 90 days. Five non-PVL histologic mimics were included as controls. Cases were re-evaluated during a consensus conference with 19 members reporting on the cases. The best inter-observer diagnostic agreement relative to PVL lesions were classified as "corrugated ortho(para)hyperkeratotic lesion, not reactive" and "SCC" (chi-square p = 0.015). There was less than moderate agreement (kappa < 0.60) for lesions in the "Bulky hyperkeratotic epithelial proliferation, not reactive" category. There was ≥ moderate agreement (> 0.41 kappa) for 35 of 48 cases. This expert consensus guideline has been developed with support and endorsement from the leadership of the American Academy of Oral and Maxillofacial Pathology and the North American Society of Head and Neck Pathologists to recommend the use of standardized histopathologic criteria and descriptive terminology to indicate three categories of lesions within PVL: (1) "corrugated ortho(para)hyperkeratotic lesion, not reactive;" (2) "bulky hyperkeratotic epithelial proliferation, not reactive;" and (3) "suspicious for," or "squamous cell carcinoma." Classification of PVL lesions based on a combination of clinical findings and these histologic descriptive categories is encouraged in order to standardize reporting, aid in future research and potentially guide clinical management.

Lichenoid proliferative leukoplakia, lichenoid lesions with evolution to proliferative leukoplakia or a continuum of the same precancerous condition? A revised hypothesis

BACKGROUND

Multiple white plaques of the oral mucosa are usually associated with potentially malignant disorders such as oral lichen planus, oral lichenoid lesions and proliferative verrucous leukoplakia. Previous studies in the current literature describe a potential clinical overlap in these entities. The aim of this study is to review clinicopathological and evolutive features of these Oral Potentially Malignant Disorders highlighting the dynamic changes of diagnoses.

DISCUSSION

It was previously hypothesized that a subset of patients with oral lichen planus or oral lichenoid diagnosis, could develop multiple white plaques during the natural history of the disease, fulfilling diagnostic criteria for proliferative verrucous leukoplakia. Consequently, these entities could, under certain conditions, obey a continuum of the same precancerous condition in the context of the field cancerization theory, increasing the risk of malignant transformation. Nevertheless, there is limited scientific evidence concerning this issue.

CONCLUSION

Further studies are needed to understand the biological and evolutive features of the link between these oral potentially malignant disorders. Regardless of its diagnosis, these patients with multifocal white lesions must be carefully monitored to detect early malignant transformation.

Architectural Alterations in Oral Epithelial Dysplasia are Similar in Unifocal and Proliferative Leukoplakia

The current WHO histopathologic criteria for oral epithelial dysplasia (ED) are based on architectural and cytologic alterations, and do not address other histopathologic features of ED. Here we propose new diagnostic criteria including architectural, organizational, and cytologic features for oral ED. Cases of unifocal leukoplakia (UL) and proliferative leukoplakia (PL) with clinical photographs and follow-up information were identified. Only cases that showed minimal cytologic atypia or mild ED were used to demonstrate critical architectural changes as defined in this study. Eight biopsies from eight UL patients and 34 biopsies from four PL patients were included. The biopsies showed (a) corrugated, verrucous or papillary architecture, (b) hyperkeratosis with epithelial atrophy, (c) bulky squamous epithelial proliferation, and (d) demarcated hyperkeratosis and "skip" segments. The architectural alterations defined here are as important as the currently used criteria for the diagnosis of ED. Clinicopathologic correlation when diagnosing oral ED is also of the utmost importance in accurate diagnosis.

Expression of Ki-67, p53, α-SMA and COX-2 in lichen planus and related lesions: A pilot study

Background

Researchers have struggled to understand the natural history of lesions presenting with both lichenoid features and epithelial dysplasia. Thus the present study was designed to differentiate between OLP, OLP with dysplasia, epithelial dysplasia and epithelial dysplasia with lichenoid features based on the expressions of ki-67, p53, COX-2, and α-SMA.

Materials and methods

Formalin-fixed paraffin-embedded archival specimens of OLP, OLP with dysplasia, epithelial dysplasia and epithelial dysplasia with lichenoid features were subjected to immunohistochemical staining with ki-67, p53, COX-2, and α-SMA.

Results

Ki-67 exhibited strong positivity in 100% (6/6) of epithelial dysplasia cases, 71.4% (5/7) of lichenoid dysplasia cases, 57.1% (4/7) of OLP cases and 60% (3/5) of OLP with dysplasia cases. Strong p53 staining was evident in more cases of lichenoid dysplasia [42.8% (3/7)], while moderate staining was more frequent in OLP cases [42.8% (3/7)] and OLP with dysplasia cases [42.8% (3/7)] and mild intensity was more frequent in epithelial dysplasia cases [50% (3/6)] followed by lichenoid dysplasia cases [42.8% (3/7)], OLP cases [28.5 (2/7)] and OLP with dysplasia cases [40% (2/5)]. COX-2 strong positivity was more frequent in cases of epithelial dysplasia cases [57.1% (4/7)] and OLP [50% (3/6)]. Strong α- SMA staining was noted more frequently in lichenoid dysplasia cases [71.4 (5/7)], followed by OLP cases [42.8% (3/7)] and OLP with dysplasia cases [60% (3/5)].

Conclusions

Ki-67, p53, α-SMA and COX-2 expression do not differentiate between OLP, LP with dysplasia and epithelial dysplasia with lichenoid features.

Oral Epithelial Dysplasia and Premalignancy

Leukoplakia and erythroplakia are two entities under the moniker of "oral potentially malignant disorders" that are highly associated with the presence of oral epithelial dysplasia (OED) at first biopsy, while lesions of submucous fibrosis develop OED after being present for years. Importantly, traumatic/frictional keratoses are often mistaken clinically for leukoplakia and it is important for the pathologist to recognize and report them as such. The features of OED have been well-described and other architectural features will be discussed here, in particular verrucous and papillary architecture, bulky epithelial proliferation and epithelial atrophy. Proliferative leukoplakia, verrucous or otherwise, often show only hyperkeratosis in early lesions, with development of OED occurring over time, and squamous cell carcinoma developing in the majority of cases over time. The concept of hyperkeratosis without features of OED and that is not reactive, is likely a precursor to the dysplastic phenotype. Many cases of leukoplakia exhibiting OED are associated with a band of lymphocytes at the interface and these should not be mistaken for oral lichen planus.

Ulcerated Lesions of the Oral Mucosa: Clinical and Histologic Review

Ulcerated lesions of the oral cavity have many underlying etiologic factors, most commonly infection, immune related, traumatic, or neoplastic. A detailed patient history is critical in assessing ulcerative oral lesions and should include a complete medical and medication history; whether an inciting or triggering trauma, condition, or medication can be identified; the length of time the lesion has been present; the frequency of episodes in recurrent cases; the presence or absence of pain; and the growth of the lesion over time. For multiple or recurrent lesions the presence or history of ulcers on the skin, genital areas, or eyes should be evaluated along with any accompanying systemic symptoms such as fever, arthritis, or other signs of underlying systemic disease. Biopsy may be indicated in many ulcerative lesions of the oral cavity although some are more suitable for clinical diagnosis. Neoplastic ulcerated lesions are notorious in the oral cavity for their ability to mimic benign ulcerative lesions, highlighting the essential nature of biopsy to establish a diagnosis in cases that are not clinically identifiable or do not respond as expected to treatment. Adjunctive tests may be required for final diagnosis of some ulcerated lesions especially autoimmune lesions. Laboratory tests or evaluation to rule out systemic disease may be also required for recurrent or severe ulcerations especially when accompanied by other symptoms. This discussion will describe the clinical and histopathologic characteristics of a variety of ulcerated lesions found in the oral cavity.

Relationship of infiltrating intraepithelial T lymphocytes in the diagnosis of oral lichen planus versus oral epithelial dysplasia: a pilot study

OBJECTIVE

The aim of this study was to identify the type and distribution of CD4+ and CD8+ T lymphocytes in oral mucosal specimens to potentially distinguish between underlying alterations or patterns in oral epithelial dysplasia and oral lichen planus.

STUDY DESIGN

This pilot study included 10 archived tissue samples that were received at the University of North Carolina Oral and Maxillofacial Pathology Laboratory and were diagnosed as oral lichen planus and moderate to severe epithelial dysplasia. Dual staining with CD4 and CD8 antibodies was carried out on each case. Slides were scanned in the Aperio ScanScope FL (Leica Biosystems, Wetzlar, Germany) and archived. Histomorphometric analysis was performed to detect inflammatory cells expressing CD4 and CD8 biomarkers in the epithelial and connective tissue regions.

RESULTS

No differences were found in the amount and ratio of CD4+/CD8+ lymphocytes among the 3 groups analyzed; however, the intraepithelial CD8+ lymphocyte distribution was strikingly different between lichen planus and moderate to severe epithelial dysplasia.

CONCLUSIONS

The localization of CD8+ cells can be potentially useful as an adjunctive diagnostic procedure to distinguish oral epithelial dysplasia from other inflammatory entities, such as lichen planus.

Lichenoid Characteristics in Premalignant Verrucous Lesions and Verrucous Carcinoma of the Oral Cavity

Verrucous hyperkeratosis (VH), verrucous carcinoma (VC) and the relentless, truly pre-malignant variant proliferative verrucous leukoplakia often exhibit lichenoid histologic features that may create a diagnostic dilemma for pathologists. This study aims to evaluate and categorize the frequency and the histopathologic patterns of lichenoid features seen in these lesions. Following IRB approval, cases of VH and VC from 1994 to 2014 were retrieved from the archives of UF Oral Pathology Biopsy Service. A panel of 4 board-certified oral and maxillofacial pathologists reviewed and scored the presence or absence of 5 lichenoid features: band-like infiltrate (BLI), saw tooth rete ridges (STRR), interface stomatitis (IS), civatte bodies (CB), and basement membrane degeneration (BMD). Cases not fulfilling the stringent selection criteria were excluded. A total of 70 cases of VH and 56 cases of VC were included. Approximately 25% of both VH and VC cases exhibited 3 or more lichenoid features. By Chi square testing, BLI (p = 0.000), IS (p = 0.005), and CB (p = 0.026) were significantly more common in VC than VH. Gingival lesions had significantly less frequent BLI (p = 0.004) and IS (p = 0.024) versus other sites. However, STRR was significantly more common in VH than VC (p = 0.000) in the gingiva. (p = 0.002). Statistical analysis revealed that the only significant valid association was the increased presence of band-like infiltrate in VC over VH (p = 0.001). Lichenoid features are common in both VH and VC and may represent a nonspecific inflammatory response to the dysplasia or malignancy rather than concomitant lichenoid disease. This could lead to significant under diagnoses of these premalignant or potentially malignant lesions by pathologists.

Oral epithelial dysplasia, atypical verrucous lesions and oral potentially malignant disorders: focus on histopathology

The term oral potentially malignant disorders (OPMDs) describes a recognizable group of mucosal diseases that have a risk of progressing to squamous cell carcinoma. Oral leukoplakia, the most common OPMD, has a 1% prevalence and reported malignant transformation rates of 2% to 5%. Other OPMDs include erythroplakia, erythroleukoplakia, submucous fibrosis, lesions of reverse smokers, and inherited genetic disorders, such as Fanconi anemia. The histopathologic assessment of OPMDs is an area of subjectivity, and oral epithelial dysplasia (OED) is fraught with both interrater variability and intrarater variability. Both architectural and cytologic changes are utilized when developing criteria for grading OED. However, the concept of atypical verrucous lesions, particularly as it pertains to proliferative verrucous leukoplakia, suffers from lack of histopathologic diagnostic criteria. Histopathologic mimics of OPMDs, including reactive/regenerative epithelium, frictional keratosis, and infection, can result in patient mismanagement. This review will focus specifically on the histologic features of OED, including human papillomavirus-associated dysplasia, as well as the histologic features of atypical verrucous keratoses/hyperplasia, particularly those that arise in the setting of proliferative verrucous leukoplakia along with OPMD mimics.

Oral lichenoid lesions: distinguishing the benign from the deadly

Oral lichen planus is a chronic inflammatory disease of unknown etiology or pathogenesis with varied disease severity that waxes and wanes over a long period of time. Although a common oral mucosal disease, accurate diagnosis is often challenging due to the overlapping clinical and histopathological features of oral lichen planus and other mucosal diseases. Other immune-mediated mucocutaneous diseases can exhibit lichenoid features including mucous membrane pemphigoid, chronic graft-versus-host disease, and discoid lupus erythematosus. Reactive changes to dental materials or to systemic medications can mimic oral lichen planus both clinically and histologically. In these situations the clinical presentation can be useful, as oral lichen planus presents as a multifocal process and is usually symmetrical and bilateral. Dysplasia of the oral cavity can exhibit a lichenoid histology, which may mask the potentially premalignant features. Proliferative verrucous leukoplakia, an unusual clinical disease, can often mimic oral lichen planus clinically, requiring careful correlation of the clinical and pathologic features.

Autoimmune Disease Manifestations in the Oral Cavity

Immune-related disorders of the oral cavity may occur as primary disease process, secondary to systemic disease or neoplasm, or as a reaction to medications and other agents. The entities represented within this group may vary significantly by severity, clinical presentation, microscopic presentation, and special testing results. The selected immune-related conditions of the oral cavity in this article are categorized and presented by their prototypical tissue reaction patterns: vesiculobullous, including acantholytic and subepithelial separation; psoriasiform; spongiotic; and lichenoid reaction patterns.

Issues related to diagnosing oral lichen planus among oral pathologists in South India: A pilot survey

AIM

In the present study, we simulated clinical scenarios by explicitly describing the history and clinical and histological features of hypothetical patients presenting with oral lichen planus (OLP), oral lichenoid lesion, and epithelial dysplasia in a self-designed questionnaire. By doing so, we aimed to elicit a diagnosis from oral pathologists and trainees, analyze their responses, appraise issues, and propose solutions regarding the diagnosis of OLP.

METHODS

The questionnaire was distributed to 100 oral pathologists and trainees in South India. Six questions were designed to assess awareness of the diagnostic aspects of OLP. Ten questions were hypothetical clinical scenarios (HCS) devised to evaluate respondents' knowledge of diagnostic guidelines and the criteria used by the respondents to render a diagnosis.

RESULTS

There were 60 of 100 responses to the questionnaire. More than half the respondents were aware of the World Health Organization and modified guidelines of OLP. We observed considerable variations in diagnoses for the HCS.

CONCLUSIONS

Our study illustrates the ambiguity in rendering an accurate diagnosis, despite adequate guidelines. Based on the responses for the HCS, we hypothesized that changes in the distribution (unilateral or bilateral) and clinical characteristic of OLP, and habits of patients, have a significant bearing on the clinical and final diagnoses of the lesion.

Diagnosis of oral lichen planus: a position paper of the American Academy of Oral and Maxillofacial Pathology

Despite being one of the most common oral mucosal diseases and recognized as early as 1866, oral lichen planus (OLP) is still a disease without a clear etiology or pathogenesis, and with uncertain premalignant potential. More research is urgently needed; however, the research material must be based on an accurate diagnosis. Accurate identification of OLP is often challenging, mandating inclusion of clinico-pathological correlation in the diagnostic process. This article summarizes current knowledge regarding OLP, discusses the challenges of making an accurate diagnosis, and proposes a new set of diagnostic criteria upon which to base future research studies. A checklist is also recommended for clinicians to provide specific information to pathologists when submitting biopsy material. The diagnostic process of OLP requires continued clinical follow-up after initial biopsy, because OLP mimics can manifest, necessitating an additional biopsy for direct immunofluorescence study and/or histopathological evaluation in order to reach a final diagnosis.

The onset risk of carcinoma in patients continuing tacrolimus topical treatment for oral lichen planus: a case report

Oral lichen planus is a chronic inflammatory mucocutaneous disease. Topical use of steroids and other immuno-modulating therapies have been tried for this intractable condition. Nowadays, tacrolimus ointment is used more commonly as a choice for treatment. However, a number of discussions have taken place after tacrolimus was reported to be carcinogenic. This report describes a patient who applied tacrolimus ointment to the lower lip after being diagnosed with oral lichen planus in 2008, and whose lesion developed squamous cell carcinoma in 2010. Since the relationship between tacrolimus and cancer development has been reported in only a few cases, including this case report, the clinician must be careful selecting tacrolimus as a second-line treatment for oral lichen planus.

[Evaluation of the clinical efficacy of a new composition of tizol with triamcinolon in complex treatment of patients with erosive ulcerous form of lichen planus of the oral mucosa]

The most significant of the primary stages of complex therapy of oral lichen planus (OLP), among causal and pathogenetic therapy is a local conservative treatment. The aim of the study was to evaluate the clinical efficacy of the local use of the new compositions TIZOL with triamcinolon in complex therapy of erosive-ulcerous forms OLP oral mucosa. The study was performed with 47 patients with lichen planus in age from 24 to 70 years with erosive-ulcerous form OLP whose diagnosis was confirmed histologically. The first group included 25 patients in the complex treatment of locally applied composition TIZOL with triamcinolon. The second group of 22 people, who in the complex treatment applied locally 0.5% prednisone ointment. The high efficiency of topical TIZOL with a highly topical steroid in the complex therapy of erosive-ulcerous forms OLP, which was confirmed by the positive clinical dynamics in all patients (100%) and high self-esteem of patients (84% positive ratings), reduced life complete epithelialization of erosions.

Clinical characteristics of lichen and dysplasia vs lichen planus cases and dysplasia cases

OBJECTIVES

To compare the clinical characteristics of lichen planus with dysplasia (LD) cases with oral dysplasia (DYS), and LP/lichenoid reaction (LP/LR).

METHODS

Patients treated at the Department of Oral Medicine with a histological diagnosis were included. Patient information (age, gender, ethnicity, smoking habits, and medical status) and parameters of oral manifestation (lesions' distribution, site, and type) were compared.

RESULTS

Two hundred and thirty five patients were included. 54% were never smokers and 25% were current smokers. The LD group (n = 79) had more bilateral cases when compared to the DYS group (n = 30), 70% to 40.7%, respectively (P = 0.008), and a lower average age [56-62, respectively (P = 0.043)]. All other parameters were similar. When compared to LR patients, the LD group had a higher percentage of men [41.8-27.9%, respectively (P = 0.08)] while all other parameters were similar.

CONCLUSIONS

As clinical characteristics of LD are more similar to the LP and LR group than to dysplasia, these findings may indicate that LD should be considered as part of the lichen planus disorder spectrum rather than a separate entity, although further analysis of larger groups is warranted. These results support the need for clinical follow-up among patients diagnosed with lichenoid changes.