Transformation Of Oral Epithelial Dysplasia Research Articles

Artificial Intelligence Applications in Oral Cancer and Oral Dysplasia.

Oral squamous cell carcinoma (OSCC) is a highly unpredictable disease with devastating mortality rates that have not changed over the past decades, in the face of advancements in treatments and biomarkers, which have improved survival for other cancers. Delays in diagnosis are frequent, leading to more disfiguring treatments and poor outcomes for patients. The clinical challenge lies in identifying those patients at the highest risk of developing OSCC. Oral epithelial dysplasia (OED) is a precursor of OSCC with highly variable behavior across patients. There is no reliable clinical, pathological, histological, or molecular biomarker to determine individual risk in OED patients. Similarly, there are no robust biomarkers to predict treatment outcomes or mortality in OSCC patients. This review aims to highlight advancements in artificial intelligence (AI)-based methods to develop predictive biomarkers of OED transformation to OSCC or predictive biomarkers of OSCC mortality and treatment response. Biomarkers such as S100A7 demonstrate promising appraisal for the risk of malignant transformation of OED. Machine learning-enhanced multiplex immunohistochemistry workflows examine immune cell patterns and organization within the tumor immune microenvironment to generate outcome predictions in immunotherapy. Deep learning (DL) is an AI-based method using an extended neural network or related architecture with multiple "hidden" layers of simulated neurons to combine simple visual features into complex patterns. DL-based digital pathology is currently being developed to assess OED and OSCC outcomes. The integration of machine learning in epigenomics aims to examine the epigenetic modification of diseases and improve our ability to detect, classify, and predict outcomes associated with epigenetic marks. Collectively, these tools showcase promising advancements in discovery and technology, which may provide a potential solution to addressing the current limitations in predicting OED transformation and OSCC behavior, both of which are clinical challenges that must be addressed in order to improve OSCC survival.

A Deep-Learning Model to Predict Risk of Malignant Transformation in Oral Epithelial Dysplasia

A Deep-Learning Model to Predict Risk of Malignant Transformation in Oral Epithelial Dysplasia

A fully automated and explainable algorithm for predicting malignant transformation in oral epithelial dysplasia

Oral epithelial dysplasia (OED) is a premalignant histopathological diagnosis given to lesions of the oral cavity. Its grading suffers from significant inter-/intra-observer variability, and does not reliably predict malignancy progression, potentially leading to suboptimal treatment decisions. To address this, we developed an artificial intelligence (AI) algorithm, that assigns an Oral Malignant Transformation (OMT) risk score based on the Haematoxylin and Eosin (H&E) stained whole slide images (WSIs). Our AI pipeline leverages an in-house segmentation model to detect and segment both nuclei and epithelium. Subsequently, a shallow neural network utilises interpretable morphological and spatial features, emulating histological markers, to predict progression. We conducted internal cross-validation on our development cohort (Sheffield; n = 193 cases) and independent validation on two external cohorts (Birmingham and Belfast; n = 89 cases). On external validation, the proposed OMTscore achieved an AUROC = 0.75 (Recall = 0.92) in predicting OED progression, outperforming other grading systems (Binary: AUROC = 0.72, Recall = 0.85). Survival analyses showed the prognostic value of our OMTscore (C-index = 0.60, p = 0.02), compared to WHO (C-index = 0.64, p = 0.003) and binary grades (C-index = 0.65, p < 0.001). Nuclear analyses elucidated the presence of peri-epithelial and intra-epithelial lymphocytes in highly predictive patches of transforming cases (p < 0.001). This is the first study to propose a completely automated, explainable, and externally validated algorithm for predicting OED transformation. Our algorithm shows comparable-to-human-level performance, offering a promising solution to the challenges of grading OED in routine clinical practice.

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.

Expression of heat shock protein 70 in oral epithelial dysplasia and squamous cell carcinoma.

Heat shock proteins (HSPs) are overexpressed in a variety of human malignancies. They are involved in tumor cell proliferation, differentiation, invasion, metastasis, death, and immune system detection. HSP 70 has been shown to resist cytotoxicity in cancer cells and even enhance tumor development through an immune escape mechanism, suggesting that HSP70 may play a role in carcinogenesis. The aim of our study was to evaluate the role of HSP70 as a predictive marker for malignant transformation in oral epithelial dysplasia. Thirty samples of epithelial dysplasia (10 mild dysplasia, 10 moderate dysplasia, and 10 severe dysplasia/carcinoma-in-situ cases), 10 samples of well-differentiated oral squamous cell carcinoma (OSCC), and 10 samples of normal oral mucosa were routinely processed, formalin-fixed, paraffin-embedded, and immunohistochemically examined for HSP70 expressions. To determine the statistical difference between two groups, a one-way analysis of variance (ANOVA) and the Mann-Whitney test were used. HSP70 expression was high but not homogenous in normal mucosa. Dysplasia showed an initial drop, and the expression increased with increasing degrees of dysplasia. There was no statistically significant difference across various types of epithelial dysplasia. From dysplasias to well-differentiated carcinoma, HSP70 exhibited a considerable rise. Overexpression of HSP70 in clinically suspicious and histologically established epithelial dysplasia may suggest a likelihood of transformation to well-differentiated OSCC and may have a prognostic value. However, more studies with a bigger sample size are needed to prove HSP70's role as a predictor.

Association between human papillomavirus and oral cancer: a literature review.

HPV plays a vital role in the development of cervical cancers and oropharyngeal cancers, but it is controversial whether HPV is involved in oral cancer development and to what extent. In this review, the clinical characteristics, diagnosis, treatment, and prognosis of HPV-positive oral cancers are summarized, and the mechanisms of HPV-related oral cancer development are discussed. HPV DNA positivity rates are 20-30% in oral squamous cell carcinoma (OSCC), and HPV16 is the most common high-risk HPV. E6/E7 mRNA positivity rates are 2-6% in OSCC. Detection of both high-risk HPV DNA and E6/E7 mRNA is recommended to determine the presence of active HPV, in agreement with high-risk HPV infection in OSCC. Surgical treatment is the first-line therapy for HPV-positive and -negative oral cancer, but there is no unified view about the prognosis of HPV-positive OSCC patients. HPV16 may play a vital role in malignant transformation in oral epithelial dysplasia, and a model of synergistic carcinogenic impact of HPV and tobacco smoking is predicted. Additionally, it is hypothesized that there are different HPV-associated oral cancers, such as integrated HPV DNA-positive OSCC with stable E6/E7 expression and episomal HPV DNA-positive OSCC. In summary, the role of HPV in oral carcinogenesis seems to be limited because of the low E6/E7 positivity in OSCCs; however, episomal HPV DNA may play a vital role in the malignant transformation of HPV-positive oral premalignant lesions. Further investigation is required to promote new insights into the role of episomal HPV DNA in oral carcinogenesis.

A study of RNA m6A demethylases in oral epithelial dysplasia and oral squamous cell carcinoma.

N6-Methyladenosine (m6A) modification is involved in the tumorigenesis of various cancers. However, the roles of RNA m6A demethylases, fat mass and obesity-associated protein (FTO), and AlkB homolog 5 (ALKBH5) in oral epithelial dysplasia (OED) and oral squamous cell carcinoma (OSCC) remain unclear. This study focuses on FTO and ALKBH5 expression by using immunohistochemistry. Twenty specimens each of OED, OSCC, and normal oral mucosa (NOM) were included. The expression pattern, the number of positive cells, the cell-staining intensity, and the histochemical scoring (H-score) were examined and analyzed. In all the OED and OSCC specimens, FTO and ALKBH5 were mainly expressed with moderate to strong staining intensity in the nuclei of the abnormal epithelial cells, respectively. Regarding the NOM, both RNA demethylases showed mild cell staining intensity and was present in 50-60% of the specimens. Interestingly, the percentage of cell positivity, the cell-staining intensity, and the H-score of the FTO and ALKBH5 in NOM, OED, and OSCC were increased, respectively (p<0.001). There was also a positive correlation between the FTO and ALKBH5 expressions in OSCC (r=0.62, p=0.003), but not in the NOM and OED. These results suggest a possible prognostic role of FTO and ALKBH5 expression in the malignant transformation of OED and tumor progression. Further studies are needed to elucidate the mechanisms underlying the roles of FTO and ALKBH5 in carcinogenesis.

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.

Immunohistochemical expression of putative cancer stem cell markers aldehyde dehydrogenase 1, SOX2, CD44 and OCT4 in different grades of oral epithelial dysplasia.

The hypothesized existence of cancer stem cells (CSC) and its markers aldehyde dehydrogenase 1 (ALDH1), CD44, SOX2 and OCT4 in oral dysplastic tissues provides the potential for a more reliable assessment of malignant transformation of oral epithelial dysplasia (OED). Thus, the present study is intended to evaluate the immunohistochemical expression of four different CSC markers ALDH1, CD44, SOX2 and OCT4 in different grades of OED and to investigate the co-expression of these putative stem cell markers in OED. A total of 35 samples of varying grades of OED which included 7 mild, 11 moderate and 17 severe dysplasia samples and 10 samples of normal oral mucosa without dysplasia were used. Four sections each from all 45 samples were stained with ALDH1, CD44, SOX2 and OCT4, respectively, by immunohistochemistry. The acquired data were analyzed and evaluated using the Chi-square test and unpaired t-test and the P < 0.05 was taken significant. ALDH1 and SOX2 expression percentages showed statistically significant differences among study groups (P < 0.05). Statistical comparison of percentage expression of CD44 and OCT4 between OED and normal was nonsignificant (P > 0.05). Co-expression of all four markers was found in 15 cases of OED with none of the normal cases showing co-expression. The expression of CSC markers in OED and normal mucosa differs significantly with co-expression of all four markers located only in dysplastic tissues. Until now, no single protein marker has been able to unequivocally identify the CSCs. Thus, a panel of putative CSC markers will help in identifying the patients with high risk for malignant transformation in OED.

Prediction of malignant transformation in oral epithelial dysplasia using machine learning

A machine learning algorithm (MLA) has been applied to a Fourier transform infrared spectroscopy (FTIR) dataset previously analysed with a principal component analysis (PCA) linear discriminant analysis (LDA) model. This comparison has confirmed the robustness of FTIR as a prognostic tool for oral epithelial dysplasia (OED). The MLA is able to predict malignancy with a sensitivity of 84 ± 3% and a specificity of 79 ± 3%. It provides key wavenumbers that will be important for the development of devices that can be used for improved prognosis of OED.

Naturally-Occurring Bioactives in Oral Cancer: Preclinical and Clinical Studies, Bottlenecks and Future Directions.

Oral cancer (OC) is the eighth most common cancer, particularly prevalent in developing countries. Current treatment includes a multidisciplinary approach, involving chemo, radio, and immunotherapy and surgery, which depends on cancer stage and location. As a result of the side effects of currently available drugs, there has been an increasing interest in the search for naturally-occurring bioactives for treating all types of cancer, including OC. Thus, this comprehensive review aims to give a holistic view on OC incidence and impact, while highlights the preclinical and clinical studies related to the use of medicinal plants for OC prevention and the recent developments in bioactive synthetic analogs towards OC management. Chemoprophylactic therapies connect the use of natural and/or synthetic molecules to suppress, inhibit or revert the transformation of oral epithelial dysplasia (DOK) into oral squamous cell carcinoma (OSCC). Novel searches have underlined the promising role of plant extracts and phytochemical compounds, such as curcumin, green tea extract, resveratrol, isothiocyanates, lycopene or genistein against this malignancy. However, poor bioavailability and lack of in vivo and clinical studies and complex pharmacokinetic profiles limit their huge potential of application. However, recent nanotechnological and related advances have shown to be promising in improving the bioavailability, absorption and efficacy of such compounds.

Malignant transformation of oral epithelial dysplasia in Southwest Finland

Oral epithelial dysplasia (OED) is considered a risk for oral squamous cell carcinoma (OSCC). A meta-analysis estimated a mean malignant transformation rate of 12.1% (95% CI 8.1–17.9). The main target of this study was to define how many OED patients develop OSCC in the hospital district of Southwest Finland. A total of 571 patients diagnosed with OED were identified. Their potential subsequent diagnosis of OSCC was derived from the Finnish Cancer Registry. The risk of OSCC development in OED patients was compared with that of the general population without OED. During a mean follow-up of 5.5 (range 0.1–29.0) years 10.9% of OED patients developed OSCC. OED patients had a 44.7-fold higher risk (95% CI 34.4–56.7) of developing OSCC than the general population. The risk was at its highest within two years of OED diagnosis. OED patients in Southwest Finland have a significantly increased risk of developing OSCC relative to the general population, especially within the first two years of dysplasia diagnosis.

Prediction of malignant transformation in oral epithelial dysplasia using infrared absorbance spectra.

Oral epithelial dysplasia (OED) is a histopathologically-defined, potentially premalignant condition of the oral cavity. The rate of transformation to frank carcinoma is relatively low (12% within 2 years) and prediction based on histopathological grade is unreliable, leading to both over- and under-treatment. Alternative approaches include infrared (IR) spectroscopy, which is able to classify cancerous and non-cancerous tissue in a number of cancers, including oral. The aim of this study was to explore the capability of FTIR (Fourier-transform IR) microscopy and machine learning as a means of predicting malignant transformation of OED. Supervised, retrospective analysis of longitudinally-collected OED biopsy samples from 17 patients with high risk OED lesions: 10 lesions transformed and 7 did not over a follow-up period of more than 3 years. FTIR spectra were collected from routine, unstained histopathological sections and machine learning used to predict malignant transformation, irrespective of OED classification. PCA-LDA (principal component analysis followed by linear discriminant analysis) provided evidence that the subsequent transforming status of these 17 lesions could be predicted from FTIR data with a sensitivity of 79 ± 5% and a specificity of 76 ± 5%. Six key wavenumbers were identified as most important in this classification. Although this pilot study used a small cohort, the strict inclusion criteria and classification based on known outcome, rather than OED grade, make this a novel study in the field of FTIR in oral cancer and support the clinical potential of this technology in the surveillance of OED.

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

Factors that increase the risk of malignant transformation of oral epithelial dysplasia (OED) are not completely elucidated. A retrospective chart review was performed assessing risk factors for transformation of OED, and cancer staging for transformed cases at Sunnybrook Health Sciences Centre. 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. 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.

Loss of FANCD2 and related proteins may predict malignant transformation in oral epithelial dysplasia

Predicting malignant transformation (MT) in oral epithelial dysplasia (OED) is challenging. The higher rate of MT reported in nonsmokers suggests an endogenous etiology in oncogenesis. We hypothesize that loss of FANCD2 and associated proteins could influence genomic instability and MT in the absence of environmental carcinogens. Longitudinal archival samples were obtained from 40 individuals with OED: from diagnosis to the most recent review in 23 patients with stable OED or until excision of the squamous cell carcinoma in 17 patients with unstable OED undergoing MT. Histopathological reassessment, immunohistochemistry for FANCD2, and Western blotting for phosphorylation/monoubiquitylation status of ATR, CHK1, FANCD2, and FANCG were undertaken on each tissue sample. Decreased expression of FANCD2 was observed in the diagnostic biopsies of OED lesions that later underwent MT. Combining the FANCD2 expression scores with histologic grading more accurately predicted MT (P=.005) than histology alone, and it correctly predicted MT in 10 of 17 initial biopsies. Significantly reduced expression of total FANCD2, pFANCD2, pATR, pCHK-1, and pFANCG was observed in unstable OED. There is preliminary evidence that defects in the DNA damage sensing/signaling/repair cascade are associated with MT in OED. Loss of expression of FANCD2 protein in association with a higher histologic grade of dysplasia offered better prediction of MT than clinicopathologic parameters alone.

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

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. 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). 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). 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. 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.

Risk Factors Associated with Malignant Transformation of Oral Epithelial Dysplasia: A Retrospective Review

Oral epithelial dysplasia (OED) is regarded as a potentially premalignant lesion; however, there is no general consensus on the malignant transformation rate or the associated risk factors.1 The purpose of this study is to report on the malignant transformation rate of OED in a tertiary care center and perform an analysis of potential clinical and histologic risk factors to better predict which lesions will transform. A retrospective chart review was performed for all patients with a diagnosis of OED at Sunnybrook Health Sciences Centre in Toronto, ON, Canada, between 2015 and 2018. Each case was assessed for malignant transformation, as well as potential risk factors. An array of statistical analyses was performed to determine the association of a multitude of clinical and histologic risk factors on outcomes. Of the 201 patients who presented with OED, 17% (34) transformed into oral squamous cell carcinoma with an average time to transformation of 33.4 months (range: 1-149 months). Seven cases had no dysplasia (hyperkeratosis) at the initial biopsy, and 12 showed only mild dysplasia. The most common site of transformation was the ventrolateral tongue (41%), followed by the buccal mucosa (29%). No significant difference was noted in malignant transformation between genders (18 male and 16 female). Risk factors were divided into 2 broad categories: lesion-specific factors (clinical appearance, location, multifocality, degree of dysplasia, and molecular characteristics) and patient-specific factors (smoking, alcohol consumption, smokeless tobacco/betel-quid use, and immunodeficiency). Beyond the well-described risk factors including smoking and alcohol and betel-quid use2, our results show both local and systemic factors that are associated with progression. We emphasize the importance of risk factor analysis in patients with a histologic diagnosis of low-grade dysplasia as close surveillance in these cases is otherwise less emphasized. It is important to understand that risk factors are dynamic, and if a patient’s risk profile changes, closer follow-up may be warranted for lesions with minimal or no dysplasia.

Evaluation of glucose transporter-1 expression in oral epithelial dysplasia and oral squamous cell carcinoma: An immunohistochemical study

Introduction:Oral squamous cell carcinoma (OSCC) is the most common malignancy of oral cavity and is commonly preceded by oral potentially malignant disorders. Glucose transporter-1 (GLUT-1) protein expression is upregulated in malignant cells that show increased glucose uptake. Alterations in GLUT-1 expression have been reported in several potentially malignant and malignant lesions.Aims and Objectives:The aims and objectives of this study were to analyze and assess the role of GLUT-1 immunomarker in oral epithelial dysplasia (OED) and OSCC, to demonstrate and analyze the presence, location and intensity of GLUT-1 immunomarker in low-risk and high-risk OEDs and in different grades of OSCC and to correlate the expression of GLUT-1 immunomarker between normal oral mucosa (NOM), OED and different grades of OSCC.Materials and Methodology:A total of ninety paraffin-embedded tissue blocks, 15 each of NOM; low-risk and high-risk OED and well, moderately and poorly differentiated OSCC were stained with the immunomarker GLUT-1.Results and Observation:GLUT-1 immunoexpression was statistically significant in terms of number of positive cells, staining intensity, IRS score and level of staining within the epithelium and also within the cell between NOM, OED and OSCC.Conclusion:Increased GLUT-1 expression has a consistent role in the malignant transformation of OED and aggressiveness of OSCC.

Evaluation of outcomes of oral epithelial dysplasia at the Leeds Dental Institute

Introduction: This study examines the role of several clinicopathological factors, in particular, appearance, size, smoking history and dysplastic grade implicated in the risk of malignant transformation of oral epithelial dysplasia (OED). It further examines factors that have less well-established foundations in predicting OED malignant transformation such as age, gender and alcohol history.

Eosinophils: An imperative histopathological prognostic indicator for oral squamous cell carcinoma.

Background:Inflammation in tumor microenvironment assists in both promotion and growth of tumor. Tumor-associated tissue eosinophilia (TATE) is the term used when eosinophils are observed in a tumor tissue with inflammatory infiltrate. Although carcinogenesis with inflammation is one of the important hallmarks, the exact role of eosinophils remains unclear. Various studies on oral squamous cell carcinoma (OSCC) that focused on eosinophils reported both favorable and unfavorable prognosis in cancer tissue, because of which the exact function of eosinophils still remains uncertain.Aims and Objectives:The present study aims at identifying the role of TATE in OSCC and in malignant transformation of oral epithelial dysplasia (OED).Materials and Methods:The study includes 70 samples that divided into two groups, of which 50 histopathologically proven cases of different grades of OSCC and 20 cases of OED (oral leukoplakia). Congo red stain was used to stain the tissue sections. Each slide was viewed under high power in 10 consecutive microscopic fields for counting of eosinophils.Results:Statistical analysis of values obtained was done using ANOVA, unpaired t-test and Mann–Whitney test. The results were statistically significant (P < 0.05) with a mean total eosinophil count of 2.12 in OED and 4.31 in OSCC.Conclusion:The present study showed higher eosinophil counts in OSCC when compared to dysplasia which should prompt for a thorough evaluation of tumor front for invasiveness. Therefore, tissue eosinophil count may be used as an adjunct to predict the malignant transformation of dysplastic lesions to OSCC.