Oral Dysplastic Lesions Research Articles

Bacteriome and mycobiome dysbiosis in oral mucosal dysplasia and oral cancer.

It has long been considered that the oral microbiome is tightly connected to oral health and that dysbiotic changes can be detrimental to the occurrence and progression of dysplastic oral mucosal lesions or oral cancer. Improved understanding of the concepts of microbial dysbiosis together with advances in high-throughput molecular sequencing of these pathologies have charted in greater microbiological detail the nature of their clinical state. This review discusses the bacteriome and mycobiome associated with oral mucosal lesions, oral candidiasis, and oral squamous cell carcinoma, aiming to delineate the information available to date in pursuit of advancing diagnostic and prognostic utilities for oral medicine.

Optical coherence tomography: Promising imaging technique for the diagnosis of oral mucosal diseases.

This review aims to summarize the latest application of optical coherence tomography (OCT) in oral mucosal diseases, promoting an accurate and earlier diagnosis of such disorders, which are difficult to be differentiated. References on the application of OCT in oral mucosal diseases were mainly obtained from PubMed, Embase, Web of Science and Scopus databases, using the keywords: "optical coherence tomography and 'oral mucosa/oral cancers/oral potentially malignant diseases/oral lichen planus/oral leukoplakia/oral erythroplakia/discoid lupus erythematosus/oral autoimmune bullous diseases/oral ulcers/erythema multiforme/oral mucositis'". It is found that OCT is showing a promising application potential in the early detection, diagnosis, differential diagnosis, monitoring of oral cancer and oral dysplastic lesions, as well as the delineation of tumor margins. OCT is also playing an increasingly important role in the diagnosis of oral potentially malignant disorders, oral mucosal bullous diseases, oral ulcerative diseases, erythema multiforme, and the early detection of oral mucositis. Optical coherence tomography, as a novel optical technique featured by real-time, noninvasive, dynamic and high-resolution imaging, is of great use to serve as an adjunct tool for the diagnosis, differential diagnosis, monitoring and therapy evaluation of oral mucosal diseases.

CD44-SNA1 integrated cytopathology for delineation of high grade dysplastic and neoplastic oral lesions.

The high prevalence of oral potentially-malignant disorders exhibits diverse severity and risk of malignant transformation, which mandates a Point-of-Care diagnostic tool. Low patient compliance for biopsies underscores the need for minimally-invasive diagnosis. Oral cytology, an apt method, is not clinically applicable due to a lack of definitive diagnostic criteria and subjective interpretation. The primary objective of this study was to identify and evaluate the efficacy of biomarkers for cytology-based delineation of high-risk oral lesions. A comprehensive systematic review and meta-analysis of biomarkers recognized a panel of markers (n: 10) delineating dysplastic oral lesions. In this observational cross sectional study, immunohistochemical validation (n: 131) identified a four-marker panel, CD44, Cyclin D1, SNA-1, and MAA, with the best sensitivity (>75%; AUC>0.75) in delineating benign, hyperplasia, and mild-dysplasia (Low Risk Lesions; LRL) from moderate-severe dysplasia (High Grade Dysplasia: HGD) along with cancer. Independent validation by cytology (n: 133) showed that expression of SNA-1 and CD44 significantly delineate HGD and cancer with high sensitivity (>83%). Multiplex validation in another cohort (n: 138), integrated with a machine learning model incorporating clinical parameters, further improved the sensitivity and specificity (>88%). Additionally, image automation with SNA-1 profiled data set also provided a high sensitivity (sensitivity: 86%). In the present study, cytology with a two-marker panel, detecting aberrant glycosylation and a glycoprotein, provided efficient risk stratification of oral lesions. Our study indicated that use of a two-biomarker panel (CD44/SNA-1) integrated with clinical parameters or SNA-1 with automated image analysis (Sensitivity >85%) or multiplexed two-marker panel analysis (Sensitivity: >90%) provided efficient risk stratification of oral lesions, indicating the significance of biomarker-integrated cytopathology in the development of a Point-of-care assay.

Micronuclei detection in oral cytologic smear: does it add diagnostic value?

BackgroundScreening and early diagnosis of oral squamous cell carcinoma (OSCC) are directly associated with increased survival rate and improved prognosis. Noninvasive diagnostic tools have been implemented in the early detection as toluidine blue staining, optical imaging, and oral cytology. This study aimed to assess and compare the presence of micronuclei (MN) in oral exfoliative cytology of healthy controls, subjects exposed to high-risk factors for oral cancer, subjects with oral potentially malignant lesions (OPMLs), and those with malignant oral lesions.Subjects and methodsA total number of 92 subjects were divided into 46 healthy controls with no oral mucosal lesions (23 with no evidence of cancer risk factors and 23 with cancer risk factors), 23 with OPMLs and 23 with oral malignant lesions. All the 92 participants were subjected to cytological sampling for detection of MN. The final diagnosis of the oral lesions was confirmed by the histopathological picture and compared to the cytological results.ResultsThe results showed that the diagnostic accuracy of MN was higher in OPMLs group (95.2%). The sensitivity of MN test in malignant group was much lower (52.2%); however, all the cytological criteria of malignancy were markedly detected as compared to the OPMLs group.ConclusionsConventional oral cytology supported by MN is highly beneficial as adjunctive tool in the screening for early detection of dysplastic oral lesions.

Study of Expression of p63 and Ki-67 in Normal, Dysplastic, and Malignant Lesions of Oral Mucosa

Background: The oral cavity is the most common site of cancer in the Indian subcontinent contributing to one-third of all cancers. The prognosis of oral dysplasia and malignant lesions can be predicted by both clinicopathological parameters and molecular markers. Aims and Objectives: The present study was undertaken to examine and compare the expression profile of cell cycle regulatory proteins p63 and Ki-67 in normal dysplastic and malignant lesions of oral mucosa and its correlation with prognosis. Settings and Design: This was a retrospective case–control study in a tertiary referral center. Materials and Methods: We evaluated and compared the expression profile of antigens p63 and Ki-67 on 60 cases of histologically proven oral dysplastic and malignant lesions oral squamous cell carcinoma (OSCC – 35 cases), oral epithelial dysplasia (OED – 15 cases), and 10 cases of benign and inflammatory oral lesions. Statistical Analysis: Mean and standard deviation were calculated and ANOVA statistical test was used to compare the data. Results: The mean labeling index of p63 and KI-67 was higher in OSCC than OED and minimum in inflammatory (controls) groups. Conclusion: p63 expression had a positive correlation with Ki-67 expression. Thus, p63 and Ki-67 may be a marker for tumorigenesis and tumor cell proliferation.

Inflammatory Cells Can Alter the Levels of H3K9ac and γH2AX in Dysplastic Cells and Favor Tumor Phenotype.

Oral potentially malignant disorders (OPMD) are clinical presentations that carry an increased risk of cancer development. Currently, epithelial dysplasia grade is based on architectural and cytological epithelial changes and is used to predict the malignant transformation of these lesions. However, predicting which OPMD will progress to a malignant tumor is very challenging. Inflammatory infiltrates can favor cancer development, and recent studies suggest that this association with OPMD lesions may be related to the etiology and/or aggressive clinical behavior of these lesions. Epigenetic changes such as histone modifications may mediate chronic inflammation and also favor tumor cells in immune resistance and evasion. This study aimed to evaluate the relationship between histone acetylation (H3K9ac) and DNA damage in the context of dysplastic lesions with prominent chronic inflammation. Immunofluorescence of "low-risk" and "high-risk" OPMD lesions (n = 24) and inflammatory fibrous hyperplasia (n = 10) as the control group was performed to assess histone acetylation levels and DNA damage through the phosphorylation of H2AX (γH2AX). Cell co-culture assays with PBMCs and oral keratinocyte cell lines (NOK-SI, DOK, and SCC-25) were performed to assess proliferation, adhesion, migration, and epithelial-mesenchymal transition (EMT). Oral dysplastic lesions showed a hypoacetylation of H3K9 and low levels of γH2AX compared to control. The contact of dysplastic oral keratinocytes with PBMCs favored EMT and the loss of cell-cell adhesion. On the other hand, p27 levels increased and cyclin E decreased in DOK, indicating cell cycle arrest. We conclude that the presence of chronic inflammation associated to dysplastic lesions is capable of promoting epigenetic alterations, which in turn can favor the process of malignant transformation.

Abnormal p53 Immunohistochemical Patterns Shed Light on the Aggressiveness of Oral Epithelial Dysplasia

The diagnosis of oral epithelial dysplasia is based on the degree of architectural and cytologic atypia in the squamous epithelium. The conventional grading system of mild, moderate, and severe dysplasia is considered by many the gold standard in predicting the risk of malignant transformation. Unfortunately, some low-grade lesions, with or without dysplasia, progress to squamous cell carcinoma (SCC) in short periods. As a result, we are proposing a new approach to characterize oral dysplastic lesions that will help identify lesions at high risk for malignant transformation. We included a total of 203 cases of oral epithelial dysplasia, proliferative verrucous leukoplakia, lichenoid, and commonly observed mucosal reactive lesions to evaluate their p53 immunohistochemical (IHC) staining patterns. We identified 4 wild-type patterns, including scattered basal, patchy basal/parabasal, null-like/basal sparing, mid-epithelial/basal sparing, and 3 abnormal p53 patterns, including overexpression basal/parabasal only, overexpression basal/parabasal to diffuse, and null. All cases of lichenoid and reactive lesions exhibited scattered basal or patchy basal/parabasal patterns, whereas human papillomavirus-associated oral epithelial dysplasia demonstrated null-like/basal sparing or mid-epithelial/basal sparing patterns. Of the oral epithelial dysplasia cases, 42.5% (51/120) demonstrated an abnormal p53 IHC pattern. p53 abnormal oral epithelial dysplasia was significantly more likely to progress to invasive SCC when compared to p53 wild-type oral epithelial dysplasia (21.6% vs 0%, P < .0001). Furthermore, p53 abnormal oral epithelial dysplasia was more likely to have dyskeratosis and/or acantholysis (98.0% vs 43.5%, P < .0001). We propose the term p53 abnormal oral epithelial dysplasia to highlight the importance of utilizing p53 IHC stain to recognize lesions that are at high risk of progression to invasive disease, irrespective of the histologic grade, and propose that these lesions should not be graded using the conventional grading system to avoid delayed management.

Intracellular calprotectin (S100A8/A9) facilitates DNA damage responses and promotes apoptosis in head and neck squamous cell carcinoma

ObjectivesIn head and neck squamous cell carcinoma (HNSCC), poor prognosis and low survival rates are associated with downregulated calprotectin. Calprotectin (S100A8/A9) inhibits cancer cell migration and invasion and facilitates G2/M cell cycle arrest. We investigated whether S100A8/A9 regulates DNA damage responses (DDR) and apoptosis in HNSCC after chemoradiation. Materials and methodsHuman HNSCC cases in TCGA were analyzed for relationships between S100A8/A9 and expression of apoptosis-related genes. Next, S100A8/A9-expressing and non-expressing carcinoma lines (two different lineages) were exposed to genotoxic agents and assessed for 53BP1 and γH2AX expression and percent of viable/dead cells. Finally, S100A8/A9-wild-type and S100A8/A9null C57BL/6j mice were treated with 4-NQO to induce oral dysplastic and carcinomatous lesions, which were compared for levels of 53BP1. ResultsIn S100A8/A9-high HNSCC tumors, apoptosis-related caspase family member genes were upregulated, whereas genes limiting apoptosis were significantly downregulated based on TCGA analyses. After X-irradiation or camptothecin treatment, S100A8/A9-expressing carcinoma cells (i.e., TR146 and KB-S100A8/A9) showed significantly higher 53BP1 and γH2AX expression, DNA fragmentation, proportions of dead cells, and greater sensitivity to cisplatin than wild-type KB or TR146-S100A8/A9-KD cells. Interestingly, KB-S100A8/A9Δ113-114 cells showed similar 53BP1 and γH2AX levels to S100A8/A9-negative KB and KB-EGFP cells. After 4-NQO treatment, 53BP1 expression in oral lesions was significantly greater in calprotectin+/+ than S100A8/A9null mice. ConclusionsIn HNSCC cells, intracellular calprotectin is strongly suggested to potentiate DDR and promote apoptosis in response to genotoxic agents. Hence, patients with S100A8/A9-high HNSCC may encounter more favorable outcomes because more tumor cells enter apoptosis with increased sensitivity to chemoradiation therapy.

Mildly dysplastic oral lesions with optically-detectable abnormalities share genetic similarities with severely dysplastic lesions

ObjectiveOptical imaging studies of oral premalignant lesions have shown that optical markers, including loss of autofluorescence and altered morphology of epithelial cell nuclei, are predictive of high-grade pathology. While these optical markers are consistently positive in lesions with moderate/severe dysplasia or cancer, they are positive only in a subset of lesions with mild dysplasia. This study compared the gene expression profiles of lesions with mild dysplasia (stratified by optical marker status) to lesions with severe dysplasia and without dysplasia. Materials and methodsForty oral lesions imaged in patients undergoing oral surgery were analyzed: nine without dysplasia, nine with severe dysplasia, and 22 with mild dysplasia. Samples were submitted for high throughput gene expression analysis. ResultsThe analysis revealed 116 genes differentially expressed among sites without dysplasia and sites with severe dysplasia; 50 were correlated with an optical marker quantifying altered nuclear morphology. Ten of 11 sites with mild dysplasia and positive optical markers (91%) had gene expression similar to sites with severe dysplasia. Nine of 11 sites with mild dysplasia and negative optical markers (82%) had similar gene expression as sites without dysplasia. ConclusionThis study suggests that optical imaging may help identify patients with mild dysplasia who require more intensive clinical follow-up. If validated, this would represent a significant advance in patient care for patients with oral premalignant lesions.

Clinical and Histologic Features Associated With Malignant Transformation of Oral Cavity Dysplasia Managed at a Single North American Institution

Reports characterizing clinical and histologic features associated with a higher risk for development of malignant lesions in the background of an oral potentially malignant disorder have largely reflected East Asian populations. Long-term studies among the North American population are rare. To evaluate risk of malignant transformation (MT) of oral dysplastic lesions by investigating the demographic, social, clinical, and histologic factors that may be associated with an increased rate as well as a decreased time to MT. This was a retrospective cohort study with medical record review at a single institution from January 1, 2000, to December 31, 2019, with follow-up for 20 years. Patients were excluded if they were younger than 18 years, the first biopsy diagnosis showed cancer, biopsies were never performed, biopsies were taken from sites outside of the oral cavity, there was no additional follow-up after the first visit, or the biopsy specimen was not characterized on the spectrum of dysplasia. Diagnosis of leukoplakia of oral mucosa, unspecified lesions of oral mucosa, or other disturbances of oral epithelium. Main outcome measures included MT rate and time to MT as well as demographic, social, clinical, physical, and histologic features associated with MT. Thirty-eight of 264 lesions (14%) in 241 patients (132 men and 109 women; mean [SD] age, 64 [13] years) underwent MT. Of the 38 lesions that underwent MT, 19 (50%) underwent transformation by 424 days, 28 (75%) by 870 days, and 34 (90%) by 1600 days. Nodularity, friability, and mass effect were more commonly observed in malignant lesions (nodularity: 42.9% vs 10.0%; difference, 32.9%; OR, 6.72; 95% CI, 3.03-14.89; friability: 42.9% vs 12.8%; difference, 30.1%; OR, 5.11; 95% CI, 1.66-15.69; mass effect: 54.2% vs 10.4%; difference, 43.8%; OR, 10.16; 95% CI, 4.12-25.09). Men were less likely than women to have multiple lesions in the oral cavity (OR, 0.40; 95% CI, 0.22-0.74). Having multiple abnormal sites was associated with higher percentage of MT (OR, 3.38; 95% CI, 1.63-7.01). In this cohort study, nodularity and mass effect were associated with lesions that may push, displace, or invade surrounding tissue, and these were more likely to be present in oral dysplastic lesions that ultimately progressed to cancer. There may be less utility in continuing surveillance beyond 5 years.

Evaluation of Efficacy of Foldscope - A Paper Microscope to be Used as a Chairside Diagnostic Tool in Oral Dysplastic Lesions: A Comparative Study.

Introduction:Precancerous lesion of the oral mucosa consists of a group of diseases which sometimes resemble each other leaving the clinician in a diagnostic dilemma. Etiology of these diseases varies geographically with most frequently being tobacco use, alcohol drinking, chewing of betel quid containing areca nut, and solar rays. The long-standing practice of these lifestyle habits causes an alteration in the mucosal barrier level leading to malignant transformation. Earlier, the diagnosis of malignant transformation was confirmed using biopsy, but the advent of exfoliative cytology showed that histological features of a cell undergoing transformation are distinctive during early stages. Early diagnosis can be lifesaving, along with chairside adjunct tools that can facilitate the clinician for better diagnosis and use it as an explanatory tool for patients.Aim:The aim of this study was to test the efficacy of foldscope as a chairside diagnostic tool to detect dysplastic changes in potentially malignant lesions affecting the oral cavity.Materials and Methods:This was a cross-sectional comparative study of a total of 54 individuals clinically diagnosed with oral premalignant lesions. Exfoliative cytological smears were taken and observed under light microscope and foldscope. After Papanicolaou stain, it was subjected to cytomorphometric analysis.Results:Cytological changes in potentially malignant lesions detected using foldscope were appreciable and found to be a mirror image of the routine light microscope.Conclusion:Morphological parameters assessed by foldscope proved to be employed in routine practice as well as in the mass screening of oral lesions.

Machine-Learning Assisted Discrimination of Precancerous and Cancerous from Healthy Oral Tissue Based on Multispectral Autofluorescence Lifetime Imaging Endoscopy.

Simple SummaryComplete resection of dysplastic and malignant tissue improves overall survival and delays cancer recurrence in oral cancer patients; however, intraoperative surgical margin assessment is limited to visual inspection and palpation, making it difficult to achieve total resection. There is currently no tool capable of providing real-time, accurate, and continuous margin-assessment guidance during oral cancer resection surgery. Multispectral autofluorescence lifetime imaging (maFLIM) is a label-free imaging modality that enables quantifying a plurality of metabolic and compositional autofluorescence biomarkers of oral dysplasia and cancer. We have developed and validated a machine-learning assisted computer aided detection (CAD) system for automated discrimination of dysplastic and cancerous from healthy oral tissue based on in vivo widefield maFLIM endoscopy data. This CAD system can be potentially embedded into maFLIM endoscopes to enable continuous in situ detection of positive margins during oral cancer resection surgery, thus facilitating maximal tumor resection and improving surgical outcomes for oral cancer patients.Multispectral autofluorescence lifetime imaging (maFLIM) can be used to clinically image a plurality of metabolic and biochemical autofluorescence biomarkers of oral epithelial dysplasia and cancer. This study tested the hypothesis that maFLIM-derived autofluorescence biomarkers can be used in machine-learning (ML) models to discriminate dysplastic and cancerous from healthy oral tissue. Clinical widefield maFLIM endoscopy imaging of cancerous and dysplastic oral lesions was performed at two clinical centers. Endoscopic maFLIM images from 34 patients acquired at one of the clinical centers were used to optimize ML models for automated discrimination of dysplastic and cancerous from healthy oral tissue. A computer-aided detection system was developed and applied to a set of endoscopic maFLIM images from 23 patients acquired at the other clinical center, and its performance was quantified in terms of the area under the receiver operating characteristic curve (ROC-AUC). Discrimination of dysplastic and cancerous from healthy oral tissue was achieved with an ROC-AUC of 0.81. This study demonstrates the capabilities of widefield maFLIM endoscopy to clinically image autofluorescence biomarkers that can be used in ML models to discriminate dysplastic and cancerous from healthy oral tissue. Widefield maFLIM endoscopy thus holds potential for automated in situ detection of oral dysplasia and cancer.

Accuracy of autofluorescence and chemiluminescence in the diagnosis of oral Dysplasia and Carcinoma: A systematic review and Meta-analysis

ObjectivesTo define the accuracy of autofluorescence-based (AF) and chemiluminescence-based (CL) systems in the diagnosis of oral dysplastic and malignant lesions in addition to the Conventional Oral Examination (COE). Materials and MethodsThe study was performed according to the PRISMA-DTA guidelines. ResultsA total of 2631 oral cavity lesions (AF, n = 2076; CL, n = 555) from 26 studies (AF = 17; CL = 9) was used for calculation of diagnostic accuracy parameters.The overall pooled sensitivity and specificity of the AF were 81.3% (95% CI: 74.3% − 87.5%) and 52.1% (95% CI: 36.9% − 67.1%), respectively. Cumulative diagnostic odds ratio (DOR) was 5.44 (95% CI: 2.29 – 10.56) with a significant heterogeneity between studies (I2 = 80.7%, 95% CI: 70.0% − 86.7%; p < .05).The overall pooled sensitivity and specificity for the CL were 84.9% (95% CI: 66.7% − 96.7%) and 51.8% (95% CI: 37.3% − 65.9%), respectively. The overall pooled DOR was 8.59 (95% CI: 2.11 – 22.38) with a significant heterogeneity between studies (I2 = 65.4%, 95% CI: 29.6% − 83.0%; p < .05). ConclusionsAF and CL present a high sensitivity in the diagnosis of dysplastic and malignant oral cavity lesions, demonstrating that diagnostic biopsies may be avoided in case of a negative test result. Both tests have a low specificity, and the reduction of the false positive rate compared to the COE alone remains poor.

Validation of a Point-of-Care Optical Coherence Tomography Device with Machine Learning Algorithm for Detection of Oral Potentially Malignant and Malignant Lesions.

Simple SummaryEarly detection is crucial towards improving survival in patients diagnosed with oral cancer. Non-invasive strategies equivalent to histology diagnosis are extremely valuable in oral cancer screening and early detection in resource-constrained settings. Optical coherence tomography (OCT), an optical biopsy technique enables real-time imaging with periodic surveillance and capability to image architectural features of the tissues. We report that while OCT system delineates oral pre-cancer and cancer with more than 90% sensitivity, integration, with artificial neural network-based analysis efficiently identifies high-risk, oral pre-cancer (83%). This study provides evidence that the robust, low-cost system was effective as a point-of-care device in resource-constrained settings. The high accuracy and portability signify widespread clinical application in oral cancer screening and/or surveillance.Non-invasive strategies that can identify oral malignant and dysplastic oral potentially-malignant lesions (OPML) are necessary in cancer screening and long-term surveillance. Optical coherence tomography (OCT) can be a rapid, real time and non-invasive imaging method for frequent patient surveillance. Here, we report the validation of a portable, robust OCT device in 232 patients (lesions: 347) in different clinical settings. The device deployed with algorithm-based automated diagnosis, showed efficacy in delineation of oral benign and normal (n = 151), OPML (n = 121), and malignant lesions (n = 75) in community and tertiary care settings. This study showed that OCT images analyzed by automated image processing algorithm could distinguish the dysplastic-OPML and malignant lesions with a sensitivity of 95% and 93%, respectively. Furthermore, we explored the ability of multiple (n = 14) artificial neural network (ANN) based feature extraction techniques for delineation high grade-OPML (moderate/severe dysplasia). The support vector machine (SVM) model built over ANN, delineated high-grade dysplasia with sensitivity of 83%, which in turn, can be employed to triage patients for tertiary care. The study provides evidence towards the utility of the robust and low-cost OCT instrument as a point-of-care device in resource-constrained settings and the potential clinical application of device in screening and surveillance of oral cancer.

PD-L1 EXPRESSION IN ORAL DYSPLASIA: A PILOT STUDY

<h3>Background</h3> Immune checkpoint inhibitor therapy has a recognized role in oral squamous cell carcinoma (OSCC). Assessment of programmed death-ligand 1 (PD-L1) expression by immunohistochemistry by a trained histopathologist is the current standard method of stratifying patients for immunotherapy. However, to date, limited work has been undertaken on PD-L1 expression in oral dysplastic lesions (ODLs). <h3>Methods and Objective</h3> The principal aims of this study were to assess the expression of PD-L1 in ODL and OSCC using a clinically validated, companion diagnostic antibody (Dako 22C3 PharmDx) and to construct a comprehensive clinicopathologic database of OSCC and ODL. PD-L1 immunohistochemistry was assessed using the combined positive score (CPS) method by a trained histopathologist. In select cases, CD3 and CD8 expression were also assessed in lymphocytes. Statistical analysis was performed using Fisher exact and Pearson chi-square tests. <h3>Results</h3> The majority of OSCC cases tested were positive for PD-L1 using the CPS method (63%; 19/30). PD-L1 expression had a positive association with lymph node metastasis but this was not statistically significant (<i>P</i> > .05). In contrast, a smaller proportion of ODLs were positive for PD-L1 (20%; 4/20), all of which were severely dysplastic. Interestingly, PD-L1 in ODL expression was associated with the presence of a dense chronic inflammatory cell infiltrate. <h3>Conclusions</h3> Evaluating PD-L1 expression using CPS could identify patients with OSCC who may respond to immune checkpoint inhibitors. We have observed PD-L1 expression in a small number of severe ODLs, the significance of which is uncertain at present. Replication in larger patient cohorts is recommended for validation.

INCORPORATION OF DIFFERENTIATED DYSPLASIA IMPROVES PREDICTION OF ORAL LEUKOPLAKIA AT INCREASED RISK OF MALIGNANT PROGRESSION

<h3>Background</h3> Oral leukoplakia is the most common oral potentially malignant disorder with a transformation rate into oral squamous cell carcinoma (SCC) of 1%-3% annually. The World Health Organization (WHO) defined dysplasia as an important histologic marker for malignant transformation risk assessment, but it is not sufficiently accurate to personalize treatment and surveillance. Differentiated dysplasia, known from differentiated vulvar intraepithelial neoplasia, is hitherto not used in oral dysplasia grading. <h3>Objective</h3> We hypothesized that assessing differentiated dysplasia besides WHO-defined (classic) dysplasia will improve oral leukoplakia malignant transformation risk assessment. <h3>Methods</h3> We investigated a retrospective cohort consisting of 84 oral leukoplakia patients for dysplasia and the expression of CK13 and CK17, known to be dysregulated in dysplastic vulvar mucosa. <h3>Results</h3> In dysplastic oral lesions, differentiated dysplasia is as common as classic dysplasia. In 25 of 84 patients (30%), SCC of the upper aerodigestive tract developed during follow-up. Considering only classic dysplasia, 11 of 56 patients (20%) with nondysplastic lesions experienced progression. With the incorporation of differentiated dysplasia, only 2 of 30 (7%) patients with nondysplastic lesions progressed. Risk of progression increased from a hazard ratio of 3.26 (<i>P</i> = .002) when only classic dysplasia was considered to 7.43 (<i>P</i> = .001) when classic and differentiated dysplasia were combined. Loss of CK13 combined with presence of dysplasia is associated with greater risk of malignant progression (<i>P</i> = .006). <h3>Conclusions</h3> This study demonstrates that differentiated dysplasia should be recognized as a separate type of dysplasia and that its distinction from classic dysplasia is of significance, since it is a strong (co)prognostic histopathological marker for oral malignant transformation. In oral lesions without dysplasia and retained CK13 staining, the risk for progression is very low.

HUMAN PAPILLOMAVIRUS (HPV)-ASSOCIATED ORAL INTRAEPITHELIAL NEOPLASIA: A CASE REPORT

<h3>Background</h3> Human papillomavirus (HPV)-associated oral intraepithelial neoplasia is a subset of oral dysplastic lesions with the presence of transcriptionally active high-risk oncogenic HPV subtypes 16 and 18. There is limited evidence in the literature regarding the potential rate of transformation of this entity to oral squamous cell carcinoma. <h3>Case Report</h3> A 51-year-old male patient with a heavy smoking (35 pack-year) and alcohol consumption (6 standard drinks a day) history presented with widespread oral leukoplakia. Initial biopsies demonstrated the following:SiteHistopathology findings1.Floor of mouthKeratosis with moderate to focally severe epithelial dysplasia2.Left lower lipActinic keratosis with mild to moderate epithelial atypiaSubsequent mapping biopsies (sites 3, 4) and wide local excision (site 5) demonstrated:3.Left ventral tongueHPV-associated intraepithelial neoplasia4.Lower lipcarcinoma in situ5.Right anterior ventral tongue/floor of mouthHPV-associated intraepithelial neoplasia, with excision margins free of dysplasia <h3>Investigations</h3> For sites 3 and 5, immunoperoxidase stains demonstrated diffuse, positive p16 staining of dysplastic epithelium and HPV-16 in situ hybridization showed positive nuclear staining. Both sites demonstrated hyperkeratosis, basal cell hyperplasia, increased numbers of mitoses (including suprabasal), and interspersed apoptotic cells. <h3>Follow-Up</h3> Wide local excision of the anterior ventral tongue and floor of mouth demonstrated HPV-associated intraepithelial neoplasia with involved margins (p16 and HPV-16-ISH positive). The lower lip vermilionectomy showed carcinoma in situ with clear margins. There is ongoing 3 monthly mucosal surveillance. <h3>Discussion</h3> Further studies are required to evaluate the behavior and prognosis of this subset of HPV-related oral dysplastic lesions.

A Comparative Study on Presence of Candida Albicans in Oral Squamous Cell Carcinoma, Oral Dysplastic Lesions and Normal Oral Mucosa

Introduction: Candida Albicans, has been suggested as a possible etiologic factor in the development of leukoplakia and oral squamous cell carcinoma. The aim of this study was to evaluate and compare the presence of Candida Albicans in samples with histopathological diagnosis of squamous cell carcinoma and dysplasia with healthy oral mucosa. Materials and Methods: This retrospective descriptive-analytical study was carried out on 30 samples in three groups (10 samples per group) with histopathological diagnosis of squamous cell carcinoma, epithelial dysplasia, and healthy mucosa. To identify Candida, used special PAS staining and a 400X optical microscope. The results of study analyzed with Fisher exact test with the 0.05 level of significance. Results: In the group diagnose with squamous cell carcinoma, Candida Albicans was present in 90% of the samples. In the other two groups with epithelial dysplasia and normal epithelium, positive PAS staining of candida was observed in 50% and 60 % samples respectively. A significant statistical difference between the group of squamous cell carcinoma and the other two groups was observed in terms of amount of Candida Albicans present in the samples. (p value &lt; 0.05), however there was no such significant between the group with epithelial dysplasia samples and the one with normal epithelium samples (p value &gt; 0.05). Discussion and conclusion. According to the results of present study and the results of previous studies, it can be concluded that Candida Albicans probably plays a role not as an etiological factor but as a factor leading to epithelial malignancies. We recommend more studies to be carried out on this topic.

Occurrence of oral neoplasms and dysplastic lesions: retrospective study of a pathology service over a 19-years period

INTRODUCTION: The epidemiological survey of the maxillofacial pathologies is of fundamental importance to prevention and treatment of these lesions. OBJECTIVE: The aim of the present study was to collect and analyze histopathological reports of biopsies sent to the Pathology Department, School of Dentistry from EBMSP. METHODS: A retrospective study of biopsies realized from 2001 to 2019 was conducted and the diagnoses of oral neoplasms and epithelial dysplasias were collected and analyzed. Data related to sex and age of the patients, location of the lesions, and clinical and histopathological diagnosis were recovered. RESULTS: From the total of 3.068 biopsies received in this period, the oral neoplasms corresponded to 7,31% of this total. Patients of the female sex (55,3%) and individuals between 25 and 64 years of age (60,3%) were most affected by neoplasms. The most common diagnosis among benign neoplasms was the ameloblastoma (20,3%) and the squamous cells carcinoma (67,2%) was the most frequent diagnosis in the group of malignant neoplasms. The anatomical location most affected by the neoplasms was the jaw (36,7%). The epithelial dysplasias corresponded to 3,8% of the sample, with a higher occurrence in the male sex (50,8%) and the age group between 25 and 64 years (61%); the anatomical location most affected was the palate (22,8%), and the mild epithelial dysplasia (68,6%) was the most common diagnosis. CONCLUSION: The present study highlights the importance of the epidemiological surveys to prevention and treatment of the maxillofacial lesions and emphasizes the necessity of the appropriate filling out of biopsies files.

Diagnostic accuracy of colposcopic examination in patients with oral dysplastic lesions

Colposcopy is a direct microscopic method and is the gold standard tool to detect early cervical dysplastic lesions. In the past, many attempts have been made to use gynecologic methods to examine the oral mucosa. The aim of this study was to detect the diagnostic accuracy of oral colposcopy in diagnosing oral dysplastic lesions in comparison with microscopic evaluation based on biopsy and compare Reid's Colposcopic Index (RCI) and the Swede scoring system in diagnosing oral dysplastic lesions. Twenty-five patients who presented for diagnosis of oral leukoplakia to the Oral Medicine and Periodontology Department, Faculty of Dentistry, Cairo University (Cairo, Egypt) and met the selection criteria were recruited in this study. Each patient was subjected to colposcopic examination, followed by biopsy to confirm the results of colposcopy. The sensitivity and specificity of oral colposcopy were calculated after colposcopic assessment by using the Swede scoring system and the RCI. The diagnostic accuracy of oral colposcopy with use of the Swede scoring system was superior to that of oral colposcopy with the use of the RCI. Colposcopic examination using the Swede scoring system is very specific for diagnosing oral epithelial dysplasia and for using the "see-and-treat" method, whereas the RCI is a very sensitive screening method for the diagnosis of oral epithelial dysplasia in oral potentially malignant disorders.