Inter- and intra-observer variability in three grading systems for oral epithelial dysplasia

Beta-defensin index: A functional biomarker for oral cancer detection

There is an unmet clinical need for a non-invasive and cost-effective test for oral squamous cell carcinoma (OSCC) that informs clinicians when a biopsy is warranted. Human beta-defensin 3 (hBD-3), an epithelial cell-derived anti-microbial peptide, is pro-tumorigenic and overexpressed in early-stage OSCC compared to hBD-2. We validate this expression dichotomy in carcinoma in situ and OSCC lesions using immunofluorescence microscopy and flow cytometry. The proportion of hBD-3/hBD-2 levels in non-invasively collected lesional cells compared to contralateral normal cells, obtained by ELISA, generates the beta-defensin index (BDI). Proof-of-principle and blinded discovery studies demonstrate that BDI discriminates OSCC from benign lesions. A multi-center validation study shows sensitivity and specificity values of 98.2% (95% confidence interval [CI] 90.3-99.9) and 82.6% (95% CI 68.6-92.2), respectively. A proof-of-principle study shows that BDI is adaptable to a point-of-care assay using microfluidics. We propose that BDI may fulfill a major unmet need in low-socioeconomic countries where pathology services are lacking.

Potential Immunohistochemical Biomarkers for Grading Oral Dysplasia: A Literature Review

Oral cancer is a prevalent global health issue, with significant morbidity and mortality rates. Despite available preventive measures, it remains one of the most common cancers, emphasising the need for improved diagnostic and prognostic tools. This review focuses on oral potentially malignant disorders (OPMDs), precursors to oral cancer, specifically emphasising oral epithelial dysplasia (OED). The World Health Organisation (WHO) provides a three-tier grading system for OED, and recent updates have expanded the criteria to enhance diagnostic precision. In the prognostic evaluation of OED, histological grading is presently regarded as the gold standard; however, its subjectivity and unreliability in anticipating malignant transformation or recurrence pose notable limitations. The primary objective is to investigate whether specific immunohistochemical biomarkers can enhance OED grading assessment according to the WHO classification. Biomarkers exhibit significant potential for comprehensive cancer risk evaluation, early detection, diagnosis, prognosis, and treatment optimisation. Technological advancements, including sequencing and nanotechnology, have expanded detection capabilities. Some analysed biomarkers are most frequently chosen, such as p53, Ki-67, cadherins/catenins, and other proteins used to differentiate OED grades. However, further research is needed to confirm these findings and discover new potential biomarkers for precise dysplasia grading and minimally invasive assessment of the risk of malignant transformation.

Diagnosis with confidence: deep learning for reliable classification of laryngeal dysplasia

BACKGROUND

Diagnosis of head and neck (HN) squamous dysplasias and carcinomas is critical for patient care, cure, and follow-up. It can be challenging, especially for grading intraepithelial lesions. Despite recent simplification in the last WHO grading system, the inter- and intraobserver variability remains substantial, particularly for nonspecialized pathologists, exhibiting the need for new tools to support pathologists.

METHODS

In this study we investigated the potential of deep learning to assist the pathologist with automatic and reliable classification of HN lesions following the 2022 WHO classification system. We created, for the first time, a large-scale database of histological samples (>2000 slides) intended for developing an automatic diagnostic tool. We developed and trained a weakly supervised model performing classification from whole-slide images (WSI). We evaluated our model on both internal and external test sets and we defined and validated a new confidence score to assess the predictions that can be used to identify difficult cases.

RESULTS

Our model demonstrated high classification accuracy across all lesion types on both internal and external test sets (respectively average area under the curve [AUC]: 0.878 (95% confidence interval [CI]: [0.834-0.918]) and 0.886 (95% CI: [0.813-0.947])) and the confidence score allowed for accurate differentiation between reliable and uncertain predictions.

CONCLUSION

Our results demonstrate that the model, associated with confidence measurements, can help in the difficult task of classifying HN squamous lesions by limiting variability and detecting ambiguous cases, taking us one step closer to a wider adoption of AI-based assistive tools.

Challenges in the assessment of epithelial dysplasia in oral lichen planus and oral lichenoid lesion: Inter and intra-observer variability of the WHO criteria and binary system

Background

Assessment of oral epithelial dysplasia is the gold standard for investigating the risk of malignant progression. The World Health Organization (WHO) methods and the binary system have limitations. This study assess the inter- and intra-observer variability of the architectural and cytological criteria and the classification of the presence and degree of epithelial dysplasia in oral lichen planus (OLP) and oral lichenoid lesion (OLL), using both the 2017 WHO criteria and the binary system.

Material and Methods

The sample consisted of 65 biopsies from lesions classified as OLP and OLL according to the American Academy of Oral and Maxillofacial Pathology (AAOMP) criteria. The histological slides were reevaluated by two oral pathologists.

Results

The individual alterations with most inter-observer disagreement were atypical mitotic figures (43.1%), loss of cohesion between epithelial cells (38.5%) and drop shape rete ridges ridges (38.5%). Inter-observer agreement analysis did not show statistically significant agreement regarding the classification of epithelial dysplasia grade by WHO criteria, only regarding the binary system classification (k=0.257; p=0.035). Intra-observer agreement analysis by evaluator 1 showed that the classification of epithelial dysplasia grade according to both methods had statistically significant agreement (k=0.546; p=0.004, k=0.861; p<0.001). Considering evaluator 2, only the evaluation of the WHO system classification showed statistically significant agreement (k=0.593; p=0.010).

Conclusions

The evaluation of epithelial dysplasia is subjective and focal changes and inflammatory infiltrate, characteristic of OLP and OLL, can increase the degree of disagreement among evaluators. The binary system presents better inter-observer agreement, while the WHO system presents better intra-observer agreement. Key words:Oral lichen planus, oral lichenoid lesion, oral lichenoid disease, dysplasia, inter-observer variation.

DNA-ICM as an adjuvant method applied on oral cytological specimens

OBJECTIVE

This study aimed to evaluate cytology diagnosis accuracy using adjuvant methods in clinical routine for oral cancer.

STUDY DESIGN

This prospective study was conducted on 98 patients with clinically potentially malignant or malignant oral cavity lesions. One oral lesion smear was taken from each patient using a cytobrush before biopsy and stored at PreservCyt Thinprep. Samples were cytologically analyzed, and DNA ploidy measurement was performed on the same slide. The diagnostic methods' accuracy was then calculated.

RESULTS

In clinical inspection, 61 patients had suspicious lesions for malignancy, whereas 37 had potentially malignant disorders. Cytology associated with DNA image cytometry presented a sensitivity of 81.2% and specificity of 90.9%. When analyzing lesions located in high-risk sites to oral malignancies individually, cytology associated with DNA image cytometry presented a sensitivity of 88.2%, specificity of 100.0%, accuracy of 90.0%, and Kappa value of 0.77 (CI 95%: 0.48-1.00).

CONCLUSIONS

Association between cytology and DNA image cytometry is an objective and non-invasive diagnostic method that demonstrated high sensitivity and specificity in diagnosing malignant epithelial squamous cell transformation in the oral cavity.

Patterns of Major Frozen Section Interpretation Error: An In-Depth Analysis From a Complex Academic Surgical Pathology Practice

OBJECTIVES

To establish baseline error rates due to misinterpretation and to identify scenarios in which major errors were most common and potentially preventable.

METHODS

Our database was queried over a 3-year period for major discrepancies due to misinterpretation. These were stratified by histomorphologic setting, service, availability/type of prior material, and years of experience and subspecialization of the interpreting pathologist.

RESULTS

The overall discordance rate between frozen section (FS) and final diagnoses was 2.9% (199/6,910). Seventy-two errors were due to interpretation, of which 34 (47.2%) were major. Major error rates were highest on the gastrointestinal and thoracic services. Of major discrepancies, 82.4% were rendered in subdisciplines outside those of the FS pathologist. Pathologists with fewer than 10 years' experience made more errors than those with more experience (55.9% vs 23.5%, P = .006). Major error rates were greater for cases without previous material compared to those with a prior glass slide (47.1% vs 17.6%, P = .009). Common histomorphologic scenarios in which disagreements were made involved discriminating mesothelial cells from carcinoma (20.6%) and accurately recognizing squamous carcinoma/severe dysplasia (17.6%).

CONCLUSIONS

To improve performance and decrease future misdiagnoses, monitoring discordances should be a continuous component of surgical pathology quality assurance programs.

A Deep Learning Onion Peeling Approach to Measure Oral Epithelium Layer Number

Head and neck squamous cell carcinoma (HNSCC), specifically in the oral cavity (oral squamous cell carcinoma, OSCC), is a common, complex cancer that significantly affects patients' quality of life. Early diagnosis typically improves prognoses yet relies on pathologist examination of histology images that exhibit high inter- and intra-observer variation. The advent of deep learning has automated this analysis, notably with object segmentation. However, techniques for automated oral dysplasia diagnosis have been limited to shape or cell stain information, without addressing the diagnostic potential in counting the number of cell layers in the oral epithelium. Our study attempts to address this gap by combining the existing U-Net and HD-Staining architectures for segmenting the oral epithelium and introducing a novel algorithm that we call Onion Peeling for counting the epithelium layer number. Experimental results show a close correlation between our algorithmic and expert manual layer counts, demonstrating the feasibility of automated layer counting. We also show the clinical relevance of oral epithelial layer number to grading oral dysplasia severity through survival analysis. Overall, our study shows that automated counting of oral epithelium layers can represent a potential addition to the digital pathology toolbox. Model generalizability and accuracy could be improved further with a larger training dataset.

Proceedings of the North American Society of Head and Neck Pathology Companion Meeting, New Orleans, LA, March 12, 2023: Oral Cavity Dysplasia: Why Does Histologic Grading Continue to be Contentious?

Head and neck squamous cell carcinoma (HNSCC) is the world's 6th most common malignancy. Oral cavity SCC (OCSCC) represents approximately one third of the HNSCC cases diagnosed annually in the United States. Despite therapeutic advances, OCSCC is frequently lethal, with a modest 5-year survival. Because OCSCC is often preceded by premalignant lesions, it is an ideal disease for screening initiatives. The conventional visual and tactile exam (CVTE), coupled with a tissue biopsy, remains the gold standard. However, CVTE alone cannot reliably differentiate between reactive/inflammatory and dysplastic lesions. Further, the histologic diagnosis of dysplasia is subjective in nature and a highly imperfect predictor of malignant transformation. This prognostic uncertainty creates a significant clinical management dilemma-watchful waiting with increased patient psychological and economic burdens versus unnecessary aggressive treatment. As such, the development and validation of novel diagnostic platforms such as Artificial Intelligence (AI) and prognostic molecular biomarkers may help address these critical unmet clinical needs.

Combination of Binary System with Ki67 Immunohistochemical Staining: a Reliable Grading Method for Oral Epithelial Dysplasia

Statement of the Problem

Oral epithelial dysplasia (OED) is a common potentially malignant lesion of oral cavity that should be managed to prevent likely malignant transformation.

Purpose

Here, we present a combination of binary grading system with complementary immunohistochemical (IHC) staining for Ki67 biomarker to provide a reproducible OED grading system.

Materials and Method

In this cross-sectional study, seventy out of one hundred OED specimens, which were accompanied by IHC stained microscopic slides for Ki67 antigen were evaluated by four independent oral pathologists. Both three-tier and binary grading systems based on WHO microscopic criteria were employed , blindly in a four-step method with at least two-week interval between each observation. Intra- and inter-observational reliability was assessed using Kappa statistical analysis.

Results

OED diagnosis based on binary system showed significant intra-observer reliability comparing to three-tier system without biomarker. Moreover, OED diagnosis based on binary system using Ki67 biomarker showed significant inter-observer reliability comparing to diagnosis in three tier system and based on binary system without Ki67 biomarker showed significant inter-observer reliability comparing to diagnosis based on three-tier system without Ki67.

Conclusion

Here, we found that application of IHC staining for Ki67 biomarker in binary system might provide a more reliable grading method for oral pathologist form different educational background.

Classification of cytological samples from oral potentially malignant lesions through Raman spectroscopy: A pilot study

The potential of Raman microspectroscopy of exfoliated cells has been demonstrated for oral cancer diagnosis. In this study, brush biopsies were collected from the buccal mucosa/tongue of healthy donors (n = 31) and from oral mucosal dysplastic lesions (n = 31 patients). Raman spectra were acquired and subjected to partial least squares-discriminant analysis (PLS-DA). The patient samples could be differentiated from healthy donor samples with 96% sensitivity and 95% specificity. Furthermore, PLS-DA models were developed based on cytopathological and histopathological assessment. Low and high grade dysplasia could be discriminated with 64% sensitivity and 65% specificity based on cytopathological assessment, while 81% sensitivity and 86% specificity could be achieved when histopathological assessment was within six months of the brush biopsy sampling. Therefore, this explorative study has successfully demonstrated that Raman spectroscopy may have a role in monitoring patients with dysplasia and may reduce the need for multiple biopsies.

Oral Epithelial Dysplasia Grading Systems: A Systematic Review & Meta-Analysis

This systematic review and meta-analysis aims to provide a robust qualitative and quantitative analysis of the different systems used to assess the grade of oral epithelial dysplasia (OED). This study was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-analyzes (PRISMA) statement. Six electronic databases were searched for primary research published over the past four decades. Overall quality and level of evidence were based on the Johns Hopkins Research Evidence Appraisal Tool, while evidence of heterogeneity was determined by the Q-statistic and I^{^2} statistic. Evidence of publication bias was determined using Egger's regression and the Rank correlation tests. A total of 170 records were identified. Only 9 primary research articles were included in the qualitative systematic review. Four studies (4/9) were included in the final quantitative meta-analysis. The grading systems analyzed included the WHO, binary, Ljubljana, Smith and Pindborg, Brothwell, and the oral intraepithelial neoplasia. The results demonstrate the binary system to be superior to the WHO system in grading OED, by providing better inter-observer agreement, however, the substantial error among the inter-observer κ values analyzed indicates the significance of this finding to be of minimal impact. Lack of reliable reproducibility of the grading systems and lack of common effect size (heterogeneity analysis) were noted.

Identification of specific clinical risk factors associated with the malignant transformation of oral epithelial dysplasia

BACKGROUND

Factors that increase the risk of malignant transformation of oral epithelial dysplasia (OED) are not completely elucidated.

METHODS

A retrospective chart review was performed assessing risk factors for transformation of OED, and cancer staging for transformed cases at Sunnybrook Health Sciences Centre.

RESULTS

Two-hundred four patients were diagnosed with OED, and 16.7% (34) underwent malignant transformation. Risk factors associated with transformation included: heavy tobacco smoking, excessive EtOH consumption, non-homogenous leukoplakia, size >200 mm² , moderate dysplasia or greater than moderate, progression of dysplasia grades, and immunosuppression. Transformed cases followed for a dysplastic lesion were associated with a stage-I cancer diagnosis, and cancer cases with no prior biopsy were associated with a stage-IV diagnosis.

CONCLUSIONS

In addition to commonly cited risk factors, immunosuppression was associated with malignant transformation, including the use of topical steroids. Analyzing risk factors can help clinicians define risk of progression in patients with OED.

Binary and WHO dysplasia grading systems for the prediction of malignant transformation of oral leukoplakia and erythroplakia: a systematic review and meta-analysis

OBJECTIVES

The aim of this systematic review was to examine the evidence of the binary histologic grading system capacity for predicting malignant transformation and to compare it with that of the WHO systems.

MATERIAL AND METHODS

A systematic review was conducted, using PubMed, EMBASE, LILACS, Web of Science, Scopus, and LIVIVO databases without any language or timeframe restrictions. Studies were included if they compared the binary and the WHO histologic grading systems in the prediction of malignant transformation of oral epithelial dysplasia (OED).

RESULTS

The capacity of the WHO and binary grading systems to predict malignant transformation ranged from 16 to 80% and from 5 to 80%, respectively. The pooled malignant transformation rate of lesions classified as severe dysplasia or carcinoma in situ by the WHO grading was 40% (95% confidence interval (CI), 0.02-0.87; I² = 92%; P = 0.00), while the corresponding value for lesions classified as high-risk by the binary grading system was 31% (95% CI, 0.00-0.84; I² = 97%; P = 0.00). Overall, there was no significant difference in prognostication accuracy between the WHO and the binary systems (odds ratio = 2.02; 95% CI, 0.88-4.64).

CONCLUSIONS

Although some studies suggest that the binary system is associated with lower inter-rater variability when grading OED, the evidence remains inconclusive on whether this system is superior to that of the WHO at predicting malignant transformation.

CLINICAL RELEVANCE

The reproducibility of the binary system has the potential to be better for prognostic purposes. However, there is no high-quality evidence to confirm if this advantage may assist clinicians in decision-making.

Rapid Validation of Whole-Slide Imaging for Primary Histopathology Diagnosis

OBJECTIVES

The ongoing global severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic necessitates adaptations in the practice of surgical pathology at scale. Primary diagnosis by whole-slide imaging (WSI) is a key component that would aid departments in providing uninterrupted histopathology diagnosis and maintaining revenue streams from disruption. We sought to perform rapid validation of the use of WSI in primary diagnosis meeting recommendations of the College of American Pathologists guidelines.

METHODS

Glass slides from clinically reported cases from 5 participating pathologists with a preset washout period were digitally scanned and reviewed in settings identical to typical reporting. Cases were classified as concordant or with minor or major disagreement with the original diagnosis. Randomized subsampling was performed, and mean concordance rates were calculated.

RESULTS

In total, 171 cases were included and distributed equally among participants. For the group as a whole, the mean concordance rate in sampled cases (n = 90) was 83.6% counting all discrepancies and 94.6% counting only major disagreements. The mean pathologist concordance rate in sampled cases (n = 18) ranged from 90.49% to 97%.

CONCLUSIONS

We describe a novel double-blinded method for rapid validation of WSI for primary diagnosis. Our findings highlight the occurrence of a range of diagnostic reproducibility when deploying digital methods.

Grading of Oral Leukoplakia: Can It be Improvised Using Immunohistochemical Markers p63 and CD31

Introduction

Oral squamous cell carcinoma is usually preceded by potentially malignant disorders (PMDs), the most common being oral leukoplakia. A conservative management protocol is followed for milder dysplastic cases, while severe dysplastic lesions are surgically excised. Several classification systems have been developed based mainly on histopathological features with a lot of inter-observer variations. The present study was done to assess the use of immunohistochemical (IHC) markers in grading leukoplakic lesions in addition to histopathological grading.

Aims and Objectives

To grade leukoplakia using different grading systems and assess if IHC markers can aid in categorizing leukoplakia.

Materials and Methods

Thirty-five cases of leukoplakia were graded using Ljubljana, 2005 World Health Organization (WHO), and Binary System followed by IHC staining with p63 and CD31.

Results and Statistics

Variation was noted in 12 cases while using WHO, 11 using Ljubljana, and 7 using Binary System and was significant on Cohen-Kappa statistics, with the least significant variation noted on Binary System. p63 staining assisted to group doubtful cases and even identify variation in cases graded positively on histopathology. In total, 17 cases stained one-third (mild/low), while 15 cases stained one-half or more (higher grade) epithelial thickness. A weak correlation was observed between all grading systems and p63 on Kendall's Tau-b analysis and the weak correlation was significant for the WHO and binary grading systems. Analyzing p63 and CD31 using Kruskal-Wallis test, an increase in mean vessel density (MVD) was noted for mild/moderate cases but decreased for severe cases.

Conclusion

Addressing histological categorization of PMDs assisted by IHC markers to understand the biological behavior of the tissues is currently essential with studies on more markers to assist in the management protocol.

Detection of deletions in 1q25, 1p36 and 1pTEL and chromosome 17 aneuploidy in oral epithelial dysplasia and oral squamous cell carcinoma by fluorescence in situ hybridization (FISH)

OBJECTIVE

To identify chromosome deletions in 1q25, 1p36 and 1pTEL, and chromosome 17 ploidy status in oral epithelial dysplasia (OED) and oral squamous cell carcinoma (OSCC).

MATERIAL AND METHODS

Samples from 57 OED and 63 OSCC were selected. FISH was performed using centromeric probes 17 and n LSIR 1p36/LSI 1q25 Dual Color Probe.

RESULTS

In OED, deletions were found only in 1pTEL region (29.8%). In OSCC, there was a higher frequency of deletion in 1pTEL (79.4%), followed by 1p36 (73.0%), and 1q25 (20.6%). Advanced TNM clinical stages (III/IV) showed all the deletions studied; at early clinical stages (I/II) of OSCC, deletions were observed only in 1pTEL. The frequency of deletion in 1p36 was 17.0 times higher in OSCC at advanced clinical stages (PR: 17.00). The median number of cell nuclei with chromosome 17 aneuploidy was higher in OSCC than in OED (P < 0.001). Early clinical stages of OSCC showed lower median number nuclei with aneuploidy when compared to advanced tumors (P < 0.05). Tumors harboring deletions in 1p36, 1q25 and 1pTEL revealed higher median numbers of trisomic/polysomic nuclei when compared to lesions exhibiting no abnormalities in chromosome 1 (P < 0.05).

CONCLUSION

A higher prevalence of chromosomal abnormalities was found in OSCC than in OED, while in OSCC, higher abnormalities were present in lesions with higher TNM staging. 1pTEL deletion and monosomy of chromosome 17 are possible markers for progression of OED to OSCC. 1p36 deletion and trisomy/polysomy of chromosome 17 could be markers of worse prognosis of OSCC.

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.

Comparison of the whole slide imaging and conventional light microscopy in the grading of oral epithelial dysplasia: a multi-institutional study

Background

Whole Slide Imaging (WSI) is an alternative method to light microscopy (LM). However, few studies have compared the diagnostic agreement between WSI and LM, especially to grade oral epithelial dysplasia (OED). The purpose of this study was to evaluate the variability in grading OED by the World Health Organization grading system, using WSI and conventional LM, and to investigate whether the access to clinical information, and psychologic or physical states of the pathologists could interfere with the diagnosis.

Material and Methods

eleven experienced pathologists from seven Brazilian universities independently evaluated twenty-five OED cases. The analyses were performed in duplicate for each method, with an interval of at least 30 days, and the time consumed in each analysis was measured. Physical and psychologic states were evaluated by blood pressure levels, heart rate and two questionnaires: State-Trait Anxiety Inventory and Perceived Stress Scale. Clinical information was provided after the second evaluation using WSI and the pathologist could change their diagnostic decision or not.

Results

LM showed a higher inter-examiner agreement (k=0.53) than WSI (k=0.45) and a smaller time consumed by the pathologists (mean of 65.53 seconds compared to 91.02 seconds in WSI). In the first analysis using conventional microscopy, there was a positive correlation between kappa values and anxiety (r=0.47, p=0.02), and stress (r=0.64, p<0.01), and an inverse correlation with heart rate (r=-0.48, p=0.02). In the digital analysis, there was also a positive correlation between kappa values and anxiety (r=0.75, p<0.001). After clinical information was given, there was a slight change in 11.3% of the cases, and a great discrepancy in 1.1% of the cases, mainly increasing the OED grade.

Conclusions

both microscopy systems had similar results, although LM had slightly higher kappa values, and WSI was more time consuming.

Key words:Pathology, microscopy, diagnosis, leukoplakia oral, anxiety.

MAGE-A expression in oral and laryngeal leukoplakia predicts malignant transformation

Leukoplakia is a potential precursor of oral as well as laryngeal squamous cell carcinoma. Risk assessment of malignant transformation based on the grade of dysplasia of leukoplakia often does not lead to reliable results. However, oral squamous cell carcinoma, laryngeal squamous cell carcinoma, and leukoplakia express single or multiple members of the melanoma-associated antigens A (MAGE-A) family, while MAGE-A are absent in healthy mucosal tissue. The present study aimed at determining if there is an association between the expression of MAGE-A in leukoplakia and malignant transformation to oral or laryngeal squamous cell carcinoma. Paraffin-embedded tissues of 205 oral and laryngeal leukoplakia, 90 corresponding tumors, and 40 healthy oral mucosal samples were included in the study. The grade of dysplasia of the leukoplakia samples was determined histopathologically. The leukoplakia samples were divided into lesions that transformed to oral and laryngeal squamous cell carcinoma (n = 91) and lesions that did not (n = 114) during a 5 years follow-up. The expression of MAGE-A3/6 and MAGE-A4 was analyzed by real-time RT-PCR. The expression of MAGE-A 1-4, 6, and 12 was determined by immunohistochemistry. A total of 59.3% of the transforming leukoplakia expressed at least one of the examined antigens as opposed to an expression rate of 3.5% of all non-transforming leukoplakia. There was no MAGE-A expression in healthy oral mucosa. The risk of malignant transformation was statistically significantly associated with MAGE-A expression in immunohistochemistry (p < 0.001) and real-time RT-PCR (MAGE-A3/6, p = 0.001; MAGE-A4, p = 0.002) analyses. There was no significant association between MAGE-A expression and the grade of dysplasia ("low-grade", D0/D1; "high-grade", D2/D3) in immunohistochemistry (p = 0.412) and real-time RT-PCR (MAGE-A3/6, p = 0.667; MAGE-A4, p = 0.756). It seems that the analysis of the MAGE-A expression profile may support the identification of leukoplakia at risk for malignant transformation. Therefore, efforts should be made to establish this analysis as a routine procedure in addition to conventional histopathology.

Inter-observer Variability in the Diagnosis of Proliferative Verrucous Leukoplakia: Clinical Implications for Oral and Maxillofacial Surgeon Understanding: A Collaborative Pilot Study

The use of diverse terminology may lead to inconsistent diagnosis and subsequent mistreatment of lesions within the proliferative verrucous leukoplakia (PVL) spectrum. The objectives of this study were: (a) to measure inter-observer variability between a variety of pathologists diagnosing PVL lesions; and (b) to evaluate the impact of diverse terminologies on understanding, interpretation, and subsequent treatment planning by oral and maxillofacial surgeons (OMFS). Six oral pathologists (OP) and six head and neck pathologists (HNP) reviewed 40 digitally scanned slides of PVL-type lesions. Inter-observer agreement on diagnoses was evaluated by Fleiss' kappa analysis. The most commonly used diagnostic terminologies were sent to ten OMFS to evaluate their resulting interpretations and potential follow-up treatment approaches. The overall means of the surgeons' responses were compared by Student t test. There was poor inter-observer agreement between pathologists on the diagnosis of PVL lesions (κ = 0.270), although there was good agreement (κ = 0.650) when diagnosing frankly malignant lesions. The lowest agreement was in diagnosing verrucous hyperplasia (VH) with/without dysplasia, atypical epithelial proliferation (AEP), and verrucous carcinoma (VC). The OMFS showed the lowest agreement on identical categories of non-malignant diagnoses, specifically VH and AEP. This study demonstrates a lack of standardized terminology and diagnostic criteria for the spectrum of PVL lesions. We recommend adopting standardized criteria and terminology, proposed and established by an expert panel white paper, to assist pathologists and clinicians in uniformly diagnosing and managing PVL spectrum lesions.

Inter-and intra-observer agreement on the judgment of toluidine blue staining for screening of oral potentially malignant disorders and oral cancer

OBJECTIVE

Toluidine blue staining (TBS) is used for screening of oral potentially malignant disorders (OPMDs) and oral cancer. Nevertheless, the judgment of TBS is based on the observer's personal experience and largely considered subjective. The aim of this study was to evaluate the inter- and intra-observer agreement on the judgment of TBS for screening of OPMDs and oral cancer.

MATERIALS AND METHODS

Two hundred randomly ordered TBS images of OPMDs and oral cancer were judged twice independently by four clinicians and four graduated students majored in oral medicine, with an interval of 3 months. Inter- and intra-observer agreement was evaluated by the Cohen's kappa (κ) coefficient. The correlation between κ-value and individual experience was assessed by Spearman's correlation coefficient.

RESULTS

For the two sets of observation, good overall inter-observer agreement was found in the study (κ = 0.620 and 0.667). Sub-group analysis yielded good inter-observer agreement both for clinicians (κ = 0.613 and 0.611) and students (κ = 0.610 and 0.665). Pairwise inter-observer agreement was presented to be moderate to excellent between clinician and clinician (κ = 0.41~0.87, 0.43~0.81), moderate to excellent between student and student (κ = 0.43~0.71, 0.53~0.82), and poor to excellent between clinician and student (κ = 0.25~0.81, 0.35~0.87). Good to excellent intra-observer agreement (κ = 0.69~0.85) was presented for eight observers. However, no correlation was illustrated between years of experience and inter- or intra-observer agreement.

CONCLUSION

Judgment of TBS has a good overall inter-observer agreement and good to excellent intra-observer agreement, which guarantees its utilization and popularity in detecting OPMDs and oral cancer.

CLINICAL RELEVANCE

To our knowledge, this is the first study to investigate the inter- and intra-observer agreement of TBS judgment. The present results revealed a good inter-observer agreement and good to excellent intra-observer agreement, which provide a beneficial supplement to the knowledge of TBS technique.

Recent Changes of Classification for Squamous Intraepithelial Lesions of the Head and Neck

CONTEXT

- Interpretation of atypical squamous lesions of the head and neck has always been a nettlesome task for pathologists. Moreover, many different grading systems for squamous intraepithelial lesions have been proposed in past decades. The recent World Health Organization 2017 classification presents 2 types of 2-tier systems for laryngeal and oral precursor lesions.

OBJECTIVE

- To review the recent changes in classification and the clinical significance for squamous intraepithelial lesions of the head and neck.

DATA SOURCES

- Personal experience and data from the literature.

CONCLUSIONS

- The 2-tier grading system for laryngeal dysplasia, presented by World Health Organization in 2017, is expected to improve diagnostic reproducibility and clinical implication. However, the diagnostic criteria for low-grade dysplasia do not distinguish it clearly from basal cell hyperplasia. The World Health Organization 2017 classification of oral epithelial dysplasia remains unclear, and complicated and variable grading systems still make head and neck intraepithelial lesions difficult to interpret.

Intraoral Potentially Malignant Disorders in a Brazilian Oral Pathology Service: Epidemiological, Clinical, and Histopathological Findings

The aim of this study was to investigate the characteristics of individuals with intraoral potentially malignant disorders (IOPMD) in an oral pathology service in Brazil. Cases were screened based on clinical diagnosis of leukoplakia (LKP), erythroleukoplakia (ELKP), and erythroplakia (EP). Clinical data and information regarding associated factors were gathered from biopsy reports. Histological diagnoses were collected from histopathological records. Among 208 IOPMD cases, 84.13% involved LKP; 11.1%, ELKP; and 4.8%, EP. The most affected sites were the gingiva and buccal mucosa. Histologically, epithelial dysplasia was present in 66.8% of the lesions, acanthosis and hyperkeratosis without epithelial dysplasia were present in 27.9%, and squamous cell carcinoma was present in 2.9%. Most patients were males, fair-skinned, with mean age of 53.4 years. Chronic smokers represented 73% of subjects, of which 30% also consumed alcohol. Smokers and drinkers were mostly males (p < 0.001). EP and ELKP represented histologically more severe degrees of epithelial dysplasia than LKP (p < 0.001). In conclusion, individuals with IOPMD were more frequently fair-skinned men in the sixth decade of life, with smoking habit. Special attention is required to clinical diagnoses of ELKP and EP since the prevalence of severe epithelial dysplasia, in situ carcinoma, and squamous cell carcinoma is higher than in LKP.