Prevalence of oral potentially malignant disorders: A systematic review and meta-analysis

Adjunctive aids for the detection of oral squamous cell carcinoma and oral potentially malignant disorders: A systematic review of systematic reviews

This study presents the results of systematic reviews on adjunctive tools in screening and diagnosis of oral squamous cell carcinoma (OSCC) and oral potentially malignant disorders (OPMD) and to determine if the current literature supports their use as either an adjunctive tool or replacement of gold standard techniques. Systemic reviews and meta-analysis that evaluated adjunctive tools including chemiluminescence, tissue autofluorescence, tissue fluorescence spectroscopy, vital staining and cytology techniques were systematically examined using AMSTAR II. Twenty-seven systematic reviews were included. Five studies had a low quality of evidence, and nine studies had a critically low quality of evidence. This review found limited evidence to recommend chemiluminescence, tissue autofluorescence tools and vital staining as diagnostic tools, but only serve as clinical adjuncts to conventional oral examination. Cytology techniques and narrow-band imaging may be utilised as a non-invasive diagnostic adjunctive tool for the detection of OSCC and the malignant transformation of OPMD. In conclusion, this paper provides evidence on several types of adjunctive tools and provides recommendations on their use in clinical practice. These tools are considered useful as clinical adjuncts but there is insufficient evidence for their use as a diagnostic tool to replace gold standard conventional oral examination and surgical biopsy.

Alteration of salivary LPO, MDA, LDH, glutathione, GPx, SOD and vitamins in oral submucous fibrosis: A three-level meta-analysis study

This study aims to investigate the alteration of salivary biomarker profiling in the development of oral submucous fibrosis (OSMF) and to explore the influence of saliva in the diagnosis of OSMF. A systematic search of published articles using the PRISMA guidelines was conducted to identify relevant studies on OSMF and saliva. All eligible studies, including case-control, cross-sectional studies, cohort, and pilot studies, contained the evaluation of salivary biomarker profiling in patients with OSMF. Salivary biomarker data from 28 selected articles were categorized into nine groups, and their mean values were determined. A three-step meta-analysis was performed by grouping salivary biomarker profiling into more heterogeneous categories based on OSMF classification, considering functional, histological, and clinical grading. The salivary biomarker profiling analysis revealed significant alterations in all markers, indicating their efficacy in OSMF diagnosis. Subgroup analyses highlighted significant associations in oxidative stress and protein with increased mean values, particularly emphasizing lipid peroxidase (LPO), malondialdehyde (MDA), and lactate dehydrogenase (LDH). Conversely, decreased mean values were observed in glutathione, glutathione peroxidase (GPx), superoxide dismutase (SOD), and vitamins. Notably, OSMF grading analysis demonstrated a significant difference in weighted effect sizes for histological grading, particularly in stage IV. The study underscores the alteration of specific salivary biomarkers, particularly those associated with LPO, MDA, LDH, glutathione, GPx, SOD, and vitamins, in diagnosing and grading OSMF.

Cancer Precursor Syndromes and Their Detection in the Head and Neck

This article explores the multifaceted landscape of oral cancer precursor syndromes. Hereditary disorders like dyskeratosis congenita and Fanconi anemia increase the risk of malignancy. Oral potentially malignant disorders, notably leukoplakia, are discussed as precursors influenced by genetic and immunologic facets. Molecular insights delve into genetic mutations, allelic imbalances, and immune modulation as key players in precancerous progression, suggesting potential therapeutic targets. The article navigates the controversial terrain of management strategies of leukoplakia, encompassing surgical resection, chemoprevention, and immune modulation, while emphasizing the ongoing challenges in developing effective, evidence-based preventive approaches.

Treatment outcomes of oral leukoplakia on the irradiated or nonirradiated mucosa among survivors of head and neck cancer in the papulation where practice of betel nut chewing and cigarette smoking are widespread

BACKGROUND

Radiotherapy (RT) has numerous effects on the oral mucosa, primarily genetic alterations and changes in the microenvironment. The characteristics of oral leukoplakia (OL) may differ between patients who have received previous head and neck cancer (HNC) treatment with radiation therapy and those who have not. Due to a lack of data on this scenario, we aimed to investigate the surgical outcomes of OL by comparing these two patient groups.

METHODS

This retrospective cohort study enrolled a total of 224 OL lesions in 124 patients who underwent carbon dioxide laser (CO2 laser) surgery from July 2002 to Aug 2021. All patients had received previous treatments for HNC, with 59 patients undergoing only surgical approach, 65 patients undergoing RT, and 46 patients undergoing concurrent chemotherapy during RT. The analysis was performed on a per-lesion basis, not a per-capita basis. We investigated the associations of clinicopathological characteristics and treatment outcomes of OL lesions that developed from irradiated or nonirradiated oral mucosa.

RESULTS

The median follow-up time was 5.87 years. Postoperative recurrence of OL occurred in 30 patients. Malignant transformation occurred in 17 patients with the incidence rate 4.19% annually and 13.7% cumulatively. The average time for OL transforming into squamous cell carcinoma was 3.27 ± 3.26 years (median 1.82, range 0.11 - 11.90). In univariate analysis, non-homogeneous morphology (P = 0.042), moderate to high-grade dysplasia (P = 0.041), and nonirradiated oral mucosa (P = 0.0047) were predictors for malignant transformation. However, in the Cox proportional hazard model, only nonirradiated oral mucosa remained an independent prognostic factor related to postoperative malignant transformation of OL (P = 0.031, HR 5.08, CI95 1.16 - 22.25).

CONCLUSION

In the population whose OL is strongly aetiologically linked to environmental carcinogens such as betel nut and tobacco, OL lesions that develop on previously irradiated oral mucosa have a lower risk for postoperative malignant transformation compared to those that develop on nonirradiated mucosa. This finding highlights the potential impacts of radiation on OL. Further research is needed to confirm this observation and elucidate the underlying mechanism.

Imiquimod for the treatment of oral leukoplakia: A two-center retrospective study

OBJECTIVES

We aimed to assess the effectiveness of the use of topical imiquimod for the management of oral leukoplakia (OL).

METHODS

This was a retrospective study. Medical chart reviews were conducted to identify patients with biopsy-proven OL treated with topical 5% imiquimod. Data included OL characteristics, histopathological diagnosis, treatment outcome, and adverse events (AEs). Treatment response was assessed by measuring the percentage reduction in the size of OL lesions.

RESULTS

33 patients (51.5% females; median age: 65 years) with 38 lesions were included. OLs were either localized (23.7%) or multifocal lesions (76.3%), with the majority on the gingiva (86.8%). Pretreatment histopathological diagnoses were dysplasia in 84.2% and nonreactive hyperkeratosis in 15.8%. Most regimens consisted of 60-minute applications, 5-days-a-week, for 6 weeks. At the end of treatment, 81.6% of 38 lesions showed a reduction in size with 68.4% exhibiting ≥50% reduction in size, and 42.1% exhibiting complete resolution. Application site reactions were the most common with pain/soreness/sensitivity occurring in 86.8%. Fatigue was the most frequently reported systemic AE (28.9%).

CONCLUSION

Two-thirds of OL lesions had ≥50% reduction in size. Most AEs were temporary and resolved upon treatment discontinuation. Prospective studies are needed to further assess Imiquimod's effectiveness in OL management.

The value of regular follow-up of oral leukoplakia for early detection of malignant transformation

OBJECTIVES

Evaluate whether regular follow-up of oral leukoplakia (OL) resulted in early detection of malignant transformation (MT).

METHOD

Two hundred and twenty-two consecutive patients with OL (147 females, 75 males); median follow-up period of 64 months (range: 12-300). Three groups were distinguished: group A (n = 92) follow-up at the hospital; group B (n = 84) follow-up by their dentist; group C (n = 46) lost to follow-up.

RESULTS

OLs in group B compared to group A, were smaller in size (<2 cm; p < 0.001), showed more hyperkeratosis (p < 0.001) and less moderate/severe dysplasia (p < 0.001). MT occurred in 45 (20%) patients: 32 (35%) in group A, five (6%) in group B and eight (17%) in group C. There was no significant difference in clinical tumour size between group A (median: 15 mm, range: 1-40) and group B (median: 10 mm, range: 3-25; p = 0.496). Tumour size was smaller for patients in groups A and B (median: 10 mm, range 1-40) compared to group C (median: 33 mm, range: 3-100; p = 0.003). There was a positive correlation between tumour size and interval between the last visit in all patients (p = 0.022).

CONCLUSION

Regular follow-up of OL resulted in early detection of MT. If properly selected, follow-up of OL performed by the dentist seems feasible.

The mechanism of IL-13 targeting IL-13Rα2 in regulating oral mucosal FBs through PI3K/AKT/mTOR

OBJECTIVE

The objective of this investigation was to examine the presence of interleukin (IL)-13 and its receptor IL-13Rα2 in the tissues of oral submucous fibrosis (OSF), investigate their biological functions, and explore the underlying mechanisms involved in the development of OSF.

MATERIALS AND METHODS

The expression of IL-13 and IL-13Rα2 in the oral mucosa of patients with OSF and normal individuals was determined through immunohistochemistry and reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Primary fibroblasts (FBs) were extracted through enzymatic digestion and then cultured. Immunofluorescence was employed to identify the FB cultures and the location of IL-13Rα2. The effects of IL-13/IL-13Rα2/PI3K/AKT/mTOR on the migration, proliferation, and secretion of fiber-related proteins of FBs were explored via the wound healing assay, CCK-8 assay, EDU assay, and RT-qPCR. The impact of IL-13Rα2 silencing and PI3K/AKT inhibition on the effect of IL-13 on FBs was analyzed by RT-qPCR and Western blotting.

RESULTS

IL-13 and IL-13Rα2 were highly expressed in OSF. Primary FBs were successfully extracted and cultured. IL-13Rα2 was found to be localized in myofibroblasts. IL-13 promoted the proliferation, migration, and secretion of fibril-associated proteins in FBs. The proliferation, migration, and secretion of fibril-associated proteins of FBs were decreased following IL-13Rα2 silencing and inhibition of the PI3K/AKT/mTOR pathway.

CONCLUSION

IL-13 may promote the proliferation, migration, and secretion of fiber-related proteins of FBs through the PI3K/AKT/mTOR pathway by targeting IL-13Rα2.

Oral Pre-malignancy: An Update on Novel Therapeutic Approaches

PURPOSE OF REVIEW

This review aims to provide a comprehensive overview of the current advances in managing and preventing progression of oral potentially malignant disorders (OPMDs), focusing on their histological and clinicopathological features, and management.

RECENT FINDINGS

Recent studies, including a multicenter cross-sectional study, have identified oral leukoplakia as the most prevalent form of OPMD, comprising over half of the cases examined. Advances in histological grading, specifically the World Health Organization's three-tier system (mild, moderate, and severe dysplasia), have significantly enhanced the accuracy of risk assessment for malignant transformation. Additionally, treatments such as surgical interventions, photodynamic therapy, and chemopreventive and molecularly targeted agents are being evaluated for their safety and efficacy as well as, immune checkpoint inhibitors being evaluated as potential preventive strategies to halt the progression of OPMDs. The management of OPMDs remains challenging due to the lack of standardized screening protocols and varied clinical management approaches. Despite this, recent advancements in diagnostic grading and therapeutic interventions provide a framework for improved treatment outcomes. Continued research into the molecular and cellular mechanisms driving development and progression of OPMDs and innovative treatment trials are essential to optimize strategies that prevent malignant progression and thereby reduce the global health burden of oral cancer.

Advancements in diagnosing oral potentially malignant disorders: leveraging Vision transformers for multi-class detection

OBJECTIVES

Diagnosing oral potentially malignant disorders (OPMD) is critical to prevent oral cancer. This study aims to automatically detect and classify the most common pre-malignant oral lesions, such as leukoplakia and oral lichen planus (OLP), and distinguish them from oral squamous cell carcinomas (OSCC) and healthy oral mucosa on clinical photographs using vision transformers.

METHODS

4,161 photographs of healthy mucosa, leukoplakia, OLP, and OSCC were included. Findings were annotated pixel-wise and reviewed by three clinicians. The photographs were divided into 3,337 for training and validation and 824 for testing. The training and validation images were further divided into five folds with stratification. A Mask R-CNN with a Swin Transformer was trained five times with cross-validation, and the held-out test split was used to evaluate the model performance. The precision, F1-score, sensitivity, specificity, and accuracy were calculated. The area under the receiver operating characteristics curve (AUC) and the confusion matrix of the most effective model were presented.

RESULTS

The detection of OSCC with the employed model yielded an F1 of 0.852 and AUC of 0.974. The detection of OLP had an F1 of 0.825 and AUC of 0.948. For leukoplakia the F1 was 0.796 and the AUC was 0.938.

CONCLUSIONS

OSCC were effectively detected with the employed model, whereas the detection of OLP and leukoplakia was moderately effective.

CLINICAL RELEVANCE

Oral cancer is often detected in advanced stages. The demonstrated technology may support the detection and observation of OPMD to lower the disease burden and identify malignant oral cavity lesions earlier.

Prediction of the short-term efficacy and recurrence of photodynamic therapy in the treatment of oral leukoplakia based on deep learning

BACKGROUND

The treatment of oral leukoplakia (OLK) with aminolaevulinic acid photodynamic therapy (ALA-PDT) is widespread. Nonetheless, there is variation in efficacy. Therefore, this study constructed a model for predicting the short-term efficacy and recurrence of OLK after ALA-PDT.

METHODS

The short-term efficacy and recurrence of ALA-PDT were calculated by statistical analysis, and the relevant influencing factors were analyzed by Logistic regression and COX regression model. Finally, prediction models for total response (TR) rate, complete response (CR) rate and recurrence in OLK patients after ALA-PDT treatment were established. Features from pathology sections were extracted using deep learning autoencoder and combined with clinical variables to improve prediction performance of the model.

RESULTS

The logistic regression analysis showed that the non-homogeneous (OR: 4.911, P: 0.023) OLK and lesions with moderate to severe epithelial dysplasia (OR: 4.288, P: 0.042) had better short-term efficacy. The area under receiver operating characteristic curve (AUC) of CR, TR and recurrence predict models after the ALA-PDT treatment of OLK patients is 0.872, 0.718, and 0.564, respectively. Feature extraction revealed an association between inflammatory cell infiltration in the lamina propria and recurrence after PDT. Combining clinical variables and deep learning improved the performance of recurrence model by more than 30 %.

CONCLUSIONS

ALA-PDT has excellent short-term efficacy in the management of OLK but the recurrence rate was high. Prediction model based on clinicopathological characteristics has excellent predictive effect for short-term efficacy but limited effect for recurrence. The use of deep learning and pathology images greatly improves predictive value of the models.

A rural teledentistry care experience: a geriatric approach to assessing oral health status and treatment needs in older adults from a Mapuche community in Chile

Background

Limited attention has been given to oral health challenges faced by older Indigenous populations, especially in rural settings, where disparities exist. This study aims to assess oral health in a rural Mapuche community in southern Chile, utilizing geriatric technology support, and exploring the connection between geriatric health and oral well-being to fill a gap in this context.

Methods

A cross-sectional study was conducted involving 76 independent older adults from a rural Mapuche community who required dental care. Assessments were in a remote care setting gathering extensive data including comprehensive geriatric assessments, medical and dental conditions using a geriatric teledentistry platform (TEGO®). Statistical analysis involved descriptive analysis, logistic regression, and both multiple correspondence analysis and k-means cluster analysis.

Results

The sample comprised individuals with limited formal education and a high degree of vulnerability. Geriatric assessments unveiled cognitive deterioration, frailty, depression risk, and multimorbidity. A distribution of the DMFT index, number of remaining teeth, number of occluding pairs, number of teeth with restorative needs and other relevant clinical findings was conducted based on sociodemographic, and medical-geriatric-dental characteristics, and additionally, a Multinomial Logistic Regression Analysis of Dentition Variables in Relation to Geriatric Assessments was performed. The dental burden was substantial, with an average DMFT index of 25.96 (SD 4.38), high prevalence of non-functional dentition (89.3%), periodontal disease (83%), xerostomia (63.2%) and oral mucosal lesions (31.5%). Age, lower education, depression, daily medication number and sugary consumption frequency were associated with a decreased average number of teeth (p < 0.05). Multiple correspondence analysis and k-means cluster analysis identified 4 clusters, with the edentulous and functional dentition groups being the most distinct.

Conclusion

This study uncovers a substantial dental burden and intricate medical-geriatric conditions interlinked among Indigenous older adults in a rural Chilean Mapuche community. The implementation of a geriatric technological ecosystem in the community enabled the resolution of less complex oral health issues and facilitated remote consultations with specialists, reducing the necessity for travel to health centers. This underscores the need for innovative dental public health initiatives to address health disparities and improve the overall well-being of older Indigenous adults.

Feasibility, Reliability, and Effectiveness of Oral cancer screening in South Asia and Southeast Asian countries: A systematic review and Meta-analysis

OBJECTIVES

The incidence of oral cancer is significantly high in South Asia and Southeast Asia. Organized screening is an effective approach to early detection. The aim of this systematic review and meta-analysis was to evaluate the reliability, diagnostic accuracy, and effectiveness of visual oral screening by community health workers (CHWs) in identifying oral cancer/oral potentially malignant disorders (OPMDs) in this region.

MATERIALS AND METHODS

We conducted a bibliographic search in PubMed, Scopus, the gray literature of Google Scholar, ProQuest dissertations, and additional manual searches. Twelve articles were included for qualitative synthesis and six for meta-analysis. Pooled sensitivity, specificity, diagnostic odds ratio (DOR), and forest plot analysis were performed.

RESULTS

Meta-analysis showed CHWs identified 8% (n = 6365) as suspicious and 92% (n = 74,140) as normal. The diagnostic accuracy of visual oral screening by CHWs showed a sensitivity of 75% (CI: 74-76) and specificity of 97% (CI: 97-97) in the detection of OPMDs/oral cancer. Forest plots were obtained using a random effects model (DOR: 24.52 (CI: 22.65-26.55)) and SAUC: 0.96 (SE = 0.05).

CONCLUSIONS

Oral visual examination by trained CHWs can be utilized for community screenings to detect oral cancer early. This approach can be used in primary healthcare to triage patients for further referral and management.

Clinical aspects of oral cancer and potentially malignant disorders in South and Southeast Asia

BACKGROUND

Oral cancer and Oral Potentially Malignant Disorders (OPMD) are major health problems in South and Southeast Asia.

AIMS

To describe and discuss the clinical aspects of Oral Cancer and OPMD in South and Southeast Asia.

MATERIALS AND METHODS

Literature review of concepts and data over the last four decades.

DISCUSSION

Asian countries account for about two-thirds of new cases of oral cancer (OC) globally, with the highest burden in the South and Southeast Asian countries, including Pakistan and India. Habits, dietary patterns, socioeconomic status, and access to routine dental care play a crucial role in defining the demographics and clinical presentation of OC in these regions and significantly influence the morbidity and mortality of the disease. This region sees the use of different types of tobacco with or without areca nut (AN), such as pan masala, gutka, gul, snuff, mawa, and mishri. Tobacco use is high among men in Sri Lanka, Myanmar, Maldives, Bangladesh, Nepal, India and Bhutan. Areca nut is the fourth most common addictive substance globally and is frequently used in South and Southeast Asian countries, including Southeast China, Hainan Island, India, Taiwan, and the Pacific Islands, and immigrants from these regions in Africa, Europe, and North America. The use of these products results in mucosal alterations with varied clinical presentation of Oral Potentially Malignant Disorders (OPMDs) and OC. We discuss here the different types of OPMD and OC, the diagnostic aids and their relevance in clinical practice, and factors that influence their prognosis.

Clinicopathological evaluation of oral leukoplakia: a single-center study of 676 cases in Japan

OBJECTIVES

To analyze the clinical and histopathological characteristics of oral leukoplakia (OL) in the Japanese population and investigate the prevalence and risk factors for epithelial dysplasia (ED) and carcinoma within lesions.

STUDY DESIGN

Data, including age, sex, lesion site, and histopathological features, of 676 cases diagnosed with OL over the previous 10 years were analyzed. Dysplasia and carcinoma prevalence were determined.

RESULTS

In male patients, the most affected site was the gingiva (42.7%), whereas in females, it was the tongue (47.6%). Moreover, ED was more prevalent in males (41.9%), whereas epithelial hyperplasia was more common in females (44.7%). A significant difference was observed between affected sites with regard to the presence of dysplasia. The ED rates by site were 64.6% and 33.7% for the tongue and gingiva, respectively (P < 0.05). The squamous cell carcinoma rates by site were 23.4%, 5.4%, and 3.4% for the tongue, buccal mucosa, and gingiva, respectively (P < 0.05). Logistic regression analysis revealed a higher prevalence of dysplasia in males than it did in females and that the risk for both dysplasia and carcinoma was highest in the tongue.

CONCLUSIONS

Dysplasia is common in OL cases, often showing carcinoma. Early biopsy and interventions are key in OL management.

Precursor Lesions, Overdiagnosis, and Oral Cancer: A Critical Review

Despite the profession placing great emphasis on oral potentially malignant disorders (OPMDs) as a gateway for early recognition and consequently better outcomes for oral cancer, the death rates for lip and oral cavity cancer have remained stagnant for three decades. Evidence shows that only a small fraction of oral cancers are in fact preceded by OPMDs, and that most OPMDs have an annual transformation rate of less than 1%. As OPMDs encompass a very heterogeneous group of oral conditions, it could be argued that only patients with oral mucosal diseases bearing a substantial risk of malignant transformation warrant close surveillance and treatment, these include proliferative leukoplakia, erythroplakia, non-homogeneous leukoplakia, as well as diseases presenting with severe dysplasia at biopsy. In this narrative review, I discuss the intricate epidemiology of the malignancies that we colloquially refer to as oral cancer, explore the limitations of focusing on OPMDs to reduce the incidence and mortality of oral cavity cancer, and argue that a may-be cancer label represents overdiagnosis for most OPMDs.

Eosinophils in Oral Disease: A Narrative Review

The prevalence of diseases characterised by eosinophilia is on the rise, emphasising the importance of understanding the role of eosinophils in these conditions. Eosinophils are a subset of granulocytes that contribute to the body's defence against bacterial, viral, and parasitic infections, but they are also implicated in haemostatic processes, including immunoregulation and allergic reactions. They contain cytoplasmic granules which can be selectively mobilised and secrete specific proteins, including chemokines, cytokines, enzymes, extracellular matrix, and growth factors. There are multiple biological and emerging functions of these specialised immune cells, including cancer surveillance, tissue remodelling and development. Several oral diseases, including oral cancer, are associated with either tissue or blood eosinophilia; however, their exact mechanism of action in the pathogenesis of these diseases remains unclear. This review presents a comprehensive synopsis of the most recent literature for both clinicians and scientists in relation to eosinophils and oral diseases and reveals a significant knowledge gap in this area of research.

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.

Improving detection of oral lesions: Eye tracking insights from a randomized controlled trial comparing standardized to conventional approach

BACKGROUND

Early detection of oral cancer (OC) or its precursors is the most effective measure to improve outcome. The reasons for missing them on conventional oral examination (COE) or possible countermeasures are still unclear.

METHODS

In this randomized controlled trial, we investigated the effects of standardized oral examination (SOE) compared to COE. 49 dentists, specialists, and dental students wearing an eye tracker had to detect 10 simulated oral lesions drawn into a volunteer's oral cavity.

RESULTS

SOE had a higher detection rate at 85.4% sensitivity compared to 78.8% in the control (p = 0.017) due to higher completeness (p < 0.001). Detection rate correlated with examination duration (p = 0.002).

CONCLUSIONS

A standardized approach can improve systematics and thereby detection rates in oral examinations. It should take at least 5 min. Perceptual and cognitive errors and improper technique cause oral lesions to be missed. Its wide implementation could be an additional strategy to enhance early detection of OC.

Immunohistochemical Expression of Epidermal Growth Factor Receptor (EGFR) in Oral Squamous Cell Carcinoma and Oral Potentially Malignant Disorders

BACKGROUND

Increased epidermal growth factor receptor (EGFR) expression has been implicated in several tumors and is associated with increased tumor advancement as well as a potential drug target. The objective of the study was to compare the immunohistochemical expression of EGFR in oral squamous cell carcinoma (OSCC) with oral potentially malignant disorders (OPMDs) and their demographic and pathologic parameters.

METHODS

This study was a comparative cross-sectional analytical study. It was conducted at the Department of Pathology, Peshawar Medical College, Riphah International University, Islamabad, Pakistan, from March 2021 to February 2022. The sample size was calculated through G Power. Thirty-eight cases of oral squamous cell carcinoma and 38 cases of oral potentially malignant disorders (OPMDs) were included in the study. Statistical analysis was performed using the Statistical Package for Social Sciences version 20.0. χ 2 tests and Fisher exact tests were applied to compare categorical variables.

RESULTS

Mean age of OSCC was 61.6±13.9, with age range from 26 to 90 years. The male-to-female ratio for OSCC was 2.16:1. Buccal mucosa was the most common site involved (34.2%). The most common histologic type was well-differentiated OSCC (71.05%) followed by poorly differentiated (16%) and moderately differentiated (13.15%). The mean age of OPMDs cases was 59.16 ± 10.81 with a male-to-female ratio of 1:1.2. Buccal mucosa was the common site (55.3%), followed by the tongue (18.4%). The OPMDs with dysplasia were 55.2%, and without dysplasia were 44.8%. A total of 55.7% of cases of OSCC showed positive EGFR expression as compared with 36.9% OPMDs cases. A higher number of low-grade OSCC cases showed increased EGFR positivity (59.3%) as compared with high grade (45.45%). EGFR positivity in OPMD cases without dysplasia was 41.2% as compared with cases with dysplasia (33.3%). The EGFR expression in OPMD cases was higher in the ≤50 age group ( P =0.001) and in females ( P =0.032), which was statistically significant.

CONCLUSIONS

EGFR expression by Immunohistochemistry may not be a helpful prognostic marker to determine the risk of OPMDs progressing to higher grades of dysplasia or invasive cancer. However, further studies relating this tumor marker to stage, lymph node metastasis, hematogenous metastasis, survival outcomes, and treatment response may give useful information regarding the utility of this marker.

Podoplanin could be a predictive biomarker of the risk of patients with oral leukoplakia to develop oral cancer: A systematic review and meta-analysis

OBJECTIVES

The aim of this study is to identify and analyze the existing literature on the utility of podoplanin to predict the risk of malignancy development (MD) in patients previously diagnosed with oral leukoplakia (OL).

METHODS

A systematic review and meta-analysis (SRMA) was performed though a search strategy using several electronic databases and a combination of keywords related to podoplanin and MD of OL, until 15 May, 2022 (PROSPERO CRD42022329326). Evaluation of the risk of bias (ROB) was performed using the Quality in Prognosis Studies Tool. The meta-analyses were estimated using fixed-effect models.

RESULTS

From 421 articles, 6 studies were finally included, that enrolled 546 patients with OL, of whom 125 presented with an oral cancer during follow-up (32 to 90 months). Some limitations regarding the ROB were identified mostly related to small sample sizes, short follow-up times, lack of information on covariables in the included studies and lack of accuracy (including sensitivity and specificity). Meta-analysis of 6 studies reveal that high expression of podoplanin carries a pooled hazard ratio (HR) of 3.72 (95% CI, 2.40-5.76; p < 0.00001) for MD without statistical heterogeneity (I2  = 0%, p = 0.53).

CONCLUSION

The results of this SRMA support the role of podoplanin immunohistochemical expression as a potential predictive biomarker to assess the risk of malignancy development in oral leukoplakia.

Oral cancer and oral potentially malignant disorders in patients with Fanconi anemia - A systematic review

The purpose of the present study was to perform a systematic review focusing on oral squamous cell carcinoma (OSCC) and oral potentially malignant disorders (OPMD) in Fanconi anemia (FA) individuals. Electronic searches were undertaken in five databases supplemented by manual scrutiny and gray literature. Case reports and/or cases series were included. The searches yielded 55 studies describing 112 cases of OSCC (n = 107) and/or OPMD (n = 5) in FA individuals. The mean age at diagnosis of OSCC/OPMD was 27.1 (±9.6) years, and females (51.8 %) were slightly more affected. Ulcer (n = 37) or mass (n = 25) were described as clinical presentations for OSCC and OPMD. White lesions (n = 4) were the most common manifestation in OPMD. Tongue (47.2 %) was the most frequent location. Sixty-one (54.5 %) individuals underwent HSCT. Surgical resection (n = 75) was the main treatment adopted. The estimated rate of OPMD malignant transformation was 1.8 % and recurrences following OSCC excision occurred in 26.8 % of individuals. Overall, at 60 months of follow-up, the probability of survival fell to 25.5 % and at 64 months the probability of recurrence increased to 63.2 %. The present data support the need for strict surveillance of patients with FA, even in the absence of OPMD, for early OSCC detection and reduction of mortality.

Oral Potentially Malignant Disorders and Oral Cancer in Saudi Arabia: An Epidemiological Review of the Literature

Background: Oral potentially malignant disorders (OPMDs) are a group of chronic oral mucosal diseases associated with an increased risk of malignant transformation. Multiple studies have investigated the prevalence of these conditions in multiple regions; however, there are limited data about the prevalence of OPMDs in the Kingdom of Saudi Arabia (KSA). This paper aims to review the prevalence of OPMDs in the KSA, to ensure better understanding of the population risk and propose a more standardised approach to the diagnosis and management of this group across the KSA. In addition, this review will discuss the prevalence of oral cancer in the KSA, considering independent risk factors for oral cancer development. Methods: Electronic databases including PubMed, Medline, Medscape, ScienceDirect, StatPearls, BMC Oral Health and the Cochrane Library were searched with the keywords "Oral Potentially Malignant Disorders"; "Saudi Arabia"; and "Oral Cancer". Identified articles were reviewed independently by 2 reviewers against defined inclusion and exclusion criteria. Results: 16 studies were included in this review. The prevalence of OPMDs in KSA varies significantly depending on age, gender, social habits, background disease and dental status. Conclusions: This review highlights the need for up-to-date data on the prevalence, distribution, and characteristics of OPMDs in KSA. The diverse prevalence rates and distinct characteristics of various OPMDs emphasise the necessity for targeted preventive measures. As the data on OPMDs in KSA remains limited, future research efforts should prioritise the establishment of comprehensive epidemiological studies to inform effective public health interventions in this region.

State of the Art in the Diagnosis and Assessment of Oral Malignant and Potentially Malignant Disorders: Present Insights and Future Outlook-An Overview

Oral Potentially Malignant Disorder (OPMD) is a significant concern for clinicians due to the risk of malignant transformation. Oral Squamous Cell Carcinoma (OSCC) is a common type of cancer with a low survival rate, causing over 200,000 new cases globally each year. Despite advancements in diagnosis and treatment, the five-year survival rate for OSCC patients remains under 50%. Early diagnosis can greatly improve the chances of survival. Therefore, understanding the development and transformation of OSCC and developing new diagnostic methods is crucial. The field of oral medicine has been advanced by technological and molecular innovations, leading to the integration of new medical technologies into dental practice. This study aims to outline the potential role of non-invasive imaging techniques and molecular signatures for the early detection of Oral Malignant and Potentially Malignant Disorders.

Salivary Biomarkers for Oral Cancer Detection: An Exploratory Systematic Review

Different efforts have been made to find better and less invasive methods for the diagnosis and prediction of oral cancer, such as the study of saliva as a source of biomarkers. The aim of this study was to perform a scoping review about salivary molecules that have been assessed as possible biomarkers for the diagnosis of oral squamous cell carcinoma (OSCC). A search was conducted using EBSCO, PubMed (MEDLINE), Scopus, and Web of Science. The research question was as follows: which molecules present in saliva have utility to be used as biomarkers for the early detection of oral cancer? Sixty-two studies were included. Over 100 molecules were assessed. Most of the markers were oriented towards the early diagnosis of OSCC and were classified based on their ability for detecting OSCC and oral potentially malignant disorders (OPMDs), OSCC outcome prediction, and the prediction of the malignant transformation of OPMDs. TNF-α, IL-1β, IL-6 IL-8, LDH, and MMP-9 were the most studied, with almost all studies reporting high sensitivity and specificity values. TNF-α, IL-1β, IL-6 IL-8, LDH, and MMP-9 are the most promising salivary biomarkers. However, more studies with larger cohorts are needed before translating the use of these biomarkers to clinical settings.

Barriers to early diagnosis and management of oral cancer in Latin America and the Caribbean

OBJECTIVE

This study aimed to explore perceived barriers to early diagnosis and management of oral cancer, as well as potential pathways for improvement in Latin America and the Caribbean (LAC).

METHODS

This cross-sectional study used a self-administered online questionnaire created via the Research Electronic Data Capture platform. The survey was distributed to health professionals trained in Oral Medicine, Oral Pathology, Oral and Maxillofacial Surgery, and Dentists with clinical and academic expertise in oral potentially malignant disorder (OPMD) and oral cancer. Data obtained were systematically organized and analyzed descriptively using Microsoft Excel.

RESULTS

Twenty-three professionals from 21 LAC countries participated. Major barriers included the limited implementation of OPMD and oral cancer control plans (17.4%), low compulsory reporting for OPMD (8.7%) and oral cancer (34.8%), unclear referral pathways for OPMD (34.8%) and oral cancer (43.5%), and a shortage of trained professionals (8.7%). Participants endorsed the utility of online education (100%) and telemedicine (91.3%).

CONCLUSION

The survey highlights major perceived barriers to early diagnosis and management of OPMD and oral cancer in LAC, as well as potential avenues for improvement.

The onset and progression of oral potentially malignant disorders in Fanconi anemia patients: Highlighting early detection of oral cancer

In 2020, Fanconi anemia (FA) was classified as a syndrome with insufficient epidemiological evidence in the oral potentially malignant disorder (OPMD) group by the WHO Collaborating Centre. The paucity of case reports on FA-associated OPMD limits evidence-based management, and such cases have not been analyzed collectively in detail. Hence, the objective of this short communication is to summarize the evidence on the onset and progression of OPMD in FA patients, so as to better understand the natural history of oral cancer development in patients affected by FA. A total of 11 eligible papers containing 1332 FA patients are involved in onset and progression of OPMD in FA patients. Of these, 186 (14.0%) were diagnosed with OPMD. With available data from 4 follow-up studies, 30 (41.1%) of 73 FA patients compatible with OPMD further developed into OSCC at young age (10-30 years old). The evidence on FA with malignant potential comprise clinical epidemiology, oral cytology abnormalities, DNA aneuploidy, loss of autofluorescence, loss of heterozygosity, high-risk human papillomavirus infection, DNA mutations in saliva and plasma samples. Collectively, these can consummate the evidence on FA as a syndrome that may potentiate cancer development in oral cavity mentioned by the WHO. Importantly, it highlights close surveillance is instrumental for FA patients with OPMD to early detect oral cancer.

[Oral cavity cancer: A distinct entity]

Oral Squamous cell carcinoma represent the 17th most frequent cancer in the world. The main risk factors are alcohol and tobacco consumption but dietary, familial, genetic, or oral diseases may be involved in oral carcinogenesis. Diagnosis is made on biopsy, but detection remains late, leading to a poor prognosis. New technologies could reduce these delays, notably Artificial Intelligence and the quantitative evaluation of salivary biological markers. Currently, management of oral cancer consists in surgery, which can be mutilating despite possible reconstructions. In the future, immunotherapies could become a therapeutic alternative and the immune microenvironment could constitute a source of prognostic markers.

Oral erythroplakia and oral erythroplakia-like oral squamous cell carcinoma - what's the difference?

BACKGROUND

Oral erythroplakia (OE) is a rare oral potentially malignant disorder, that has a high rate of malignant transformation. The definition of OE still lacks uniformity. In particular, lesions that look clinically like erythroplakias, but are histopathologically diagnosed as squamous cell carcinomas are still sometimes called erythroplakias. The purpose of this study is to present demographic and clinicopathologic features of a series of OEs and clinically oral erythroplakia -like squamous cell carcinomas (OELSCC), to study their differences and to discuss the definition of OE.

METHODS

A multicenter retrospective case series of OEs and OELSCCs. Descriptive statistics were used to analyze the data.

RESULTS

11 cases of OEs and 9 cases of OELSCCs were identified. The mean age of the OE patients was 71 years and 72.7% were female, while the mean age of the OELSCC patients was 69 years, and all were female. 9% of the OE and 22% of the OELSCC patients had smoked or were current smokers. 72.7% of the OEs and 55.5% of OELSCCs were uniformly red lesions. 63.6% of the OE and 22% of the OELSCC patients had a previous diagnosis of oral lichenoid disease (OLD). The malignant transformation rate of OE was 9% in a mean of 73 months.

CONCLUSIONS

OE and OELSCC may arise de novo or in association with OLD. Tobacco and alcohol use were not prevalent in the present cases. The clinical features of OEs and OELSCC are similar, but symptoms, uneven surface and ulceration may be more common in OELSCCs than in OEs. Clinical recognition of OE is important since it may mimic other, more innocuous red lesions of the oral mucosa. The diagnosis of OE requires biopsy and preferably an excision. Clarification of the definition of OE would aid in clinical diagnostics.

The role of differentiated dysplasia in the prediction of malignant transformation of oral leukoplakia

OBJECTIVE

Oral leukoplakia is the most common oral potentially malignant disorder. Malignant transformation of oral leukoplakia occurs at an annual rate of 1%-7%. WHO-defined classic epithelial dysplasia is an important predictor of malignant transformation of oral leukoplakia, but we have previously shown in a proof of concept study that prediction improves by incorporation of an architectural pattern of dysplasia, also coined as differentiated dysplasia. We aimed to analyze this finding in a larger cohort of patients.

METHOD

For this retrospective study 176 oral leukoplakia patients were included. Biopsies for all patients were assessed for the presence of dysplasia and analyzed for cytokeratin 13 and 17 expression. Moreover, the inter-observer agreement for the diagnosis of differentiated dysplasia was determined.

RESULTS

In total, 33 of 176 patients developed oral squamous cell carcinoma during follow-up. Presence of classic epithelial dysplasia increased cancer risk two-fold (HR = 2.18, p = 0.026). Lesions without classic epithelial dysplasia could be further risk-stratified by the presence of differentiated dysplasia (HR = 7.36, p < 0.001). Combined classic epithelial and differentiated dysplasia imparted a seven-fold increased risk of malignant transformation (7.34, p = 0.001). Inter-observer agreement for the diagnosis of dysplasia, including differentiated dysplasia, was moderate (κ = 0.56, p < 0.001).

DISCUSSION

This study emphasizes the importance of the recognition of the architectural pattern of differentiated dysplasia as a separate entity for risk prediction of malignant transformation of oral leukoplakia. Presence of any pattern of dysplasia results in accurate prediction of malignant transformation risk of oral leukoplakia.

Aging and oral squamous cell carcinoma development: the role of cellular senescence

The gradual accumulation and inadequate renewal of senescent cells over time drive organismal aging. Senescent cells undergo altered gene expression and release inflammatory mediators collectively termed the senescence-associated secretory phenotype (SASP), which significantly contributes to a spectrum of age-related disorders, including cancer. In the context of carcinogenesis, the SASP produced by senescent cells has been implicated in the promotion of epithelial cancers, including oral squamous cell carcinoma (OSCC), the most common form of oral cancer. Senescent cells within the tumor microenvironment release factors that amplify the growth and invasiveness of neighboring cancer cells. Senotherapeutics, including senolytics and senomorphics, emerge as promising modalities to target senescent cells and their associated inflammatory factors, thereby opening novel avenues for augmenting the efficacy of cancer treatments. Here, we review the general aspects of cellular senescence, focusing on the relation between senescence-related inflammation with cancer development. We also analyze the available evidence linking cellular senescence with OSCC, highlighting possible clinical applications.

Importance of the vaporization margin during CO2 laser treatment of oral leukoplakia: A survival study

OBJECTIVES

The main purpose of this study was to assess the response of oral leukoplakia to CO2 laser vaporization treatment, as well as determining possible factors that may affect recurrence of lesions.

MATERIALS AND METHODS

A retrospective study was conducted, in which the medical records of patients who had been clinically and histologically diagnosed with oral leukoplakia and treated with CO2 laser between 1996 and 2019 at the Oral Medicine Teaching Unit of the Faculty of Dentistry of the University of Santiago de Compostela were reviewed.

RESULTS

Fifty-eight patients were included: 36 female and 22 male subjects, with a mean age of 63.7 years old (SD ±13.1). The average follow-up time was 57.5 months (SD ±57.9). A relapse rate of 52.6% was determined. Of all the studied variables, the margin was the only one for which a statistically significant association with recurrence of lesions was demonstrated (p < 0.05).

CONCLUSION

The vaporization of lesions using CO2 laser with a safety margin of at least 3 mm from the clinical limits of OL is a key factor in preventing recurrence.

Streptococcus mitis and Prevotella melaninogenica Influence Gene Expression Changes in Oral Mucosal Lesions in Periodontitis Patients

Oral microbiome disruptions in periodontitis are related to the chronic inflammatory reactions that could in turn lead to the development of multiple oral diseases. The objective of the study was to assess the frequencies of Streptococcus mitis, Prevotella melaninogenica, and Prevotella intermedia in oral benign lesions, oral potentially malignant disorders (OPMDs), and oral squamous cell carcinomas (OSCCs) and investigate the impact of these bacteria on the expression patterns of the selected (potential) target genes (PI3CA/AKT2/mTOR, DUSP16/MAPK14, and COX2). After sample collection (25 benign lesions, 30 OPMDs, and 35 OSCCs) and DNA/RNA extraction, quantitative real-time polymerase chain reaction (qPCR) was performed to detect bacterial presence and assess relative gene expression levels in different lesion groups. Prevotella melaninogenica was the most prevalent of the three analyzed bacteria, with the frequency being 60% in benign lesions, 87% in OPMDs (p = 0.024), and 77% in OSCC. The OPMD tissues in which Prevotella melaninogenica was present exhibited a higher expression level of AKT2 (p = 0.042). Significantly lower expression of DUSP16 was observed in OSCC tissues containing Streptococcus mitis (p = 0.011). The obtained results indicate a substantial contribution of P. melaninogenica and Str. mitis in the pathogenesis of oral mucosal lesions, possibly via AKT2 upregulation and DUSP16 downregulation.

Oral squamous cell carcinomas: state of the field and emerging directions

Oral squamous cell carcinoma (OSCC) develops on the mucosal epithelium of the oral cavity. It accounts for approximately 90% of oral malignancies and impairs appearance, pronunciation, swallowing, and flavor perception. In 2020, 377,713 OSCC cases were reported globally. According to the Global Cancer Observatory (GCO), the incidence of OSCC will rise by approximately 40% by 2040, accompanied by a growth in mortality. Persistent exposure to various risk factors, including tobacco, alcohol, betel quid (BQ), and human papillomavirus (HPV), will lead to the development of oral potentially malignant disorders (OPMDs), which are oral mucosal lesions with an increased risk of developing into OSCC. Complex and multifactorial, the oncogenesis process involves genetic alteration, epigenetic modification, and a dysregulated tumor microenvironment. Although various therapeutic interventions, such as chemotherapy, radiation, immunotherapy, and nanomedicine, have been proposed to prevent or treat OSCC and OPMDs, understanding the mechanism of malignancies will facilitate the identification of therapeutic and prognostic factors, thereby improving the efficacy of treatment for OSCC patients. This review summarizes the mechanisms involved in OSCC. Moreover, the current therapeutic interventions and prognostic methods for OSCC and OPMDs are discussed to facilitate comprehension and provide several prospective outlooks for the fields.

The global prevalence of oral leukoplakia: a systematic review and meta-analysis from 1996 to 2022

BACKGROUND

Oral leukoplakia(OLK) is a common oral potentially malignant disorder. The global prevalence of solely OLK was published in 2003, while the prevalence varied among different studies. In recent years, large-scale summary and definition-related analyses obtain insufficient attention. This study aimed to perform a systematic review of prevalence studies of oral leukoplakia and assess predisposing factors of its occurrence.

METHODS

The search terms ("Oral leukoplakia" OR OLK OR leukoplakia) AND (prevalence OR incidence OR epidemiology) were searched in databases (Pubmed, Embase, Scopus, and Web of Science) for OLK studies published from January 1996 until December 2022. The estimated prevalence calculation and risk of bias analysis used STATA 16.0.

RESULTS

We obtained 69 studies, including 1,263,028 participants, from 28 countries, and 6 continents. The prevalence was 1.39%, varying from 0.12 to 33.33%. The overall pooled estimated prevalence of OLK was 2.23% for population-based studies, 1.36% for clinic-based population studies, and 9.10% for specific populations. The pooled prevalence in different continents ranged from 0.33 to 11.74% with a statistical difference in the population-based calculation. The estimated prevalence of OLK was higher in males than in females. Those who smoked and consumed alcohol had a higher prevalence than those who did not.

CONCLUSION

Combining data from 69 published studies, the prevalence of OLK was determined as 1.39% and the pooling estimated global prevalence was 3.41%. The prevalence was relatively consistent and stable across different continents and different definitions. A higher pooled estimated prevalence was found among males, those aged over 60 years old, smokers, and alcohol consumers. The results from the included studies in this systematic review revealed that the prevalence was relatively consistent and stable across various definitions and continents, which may help in developing global treatment and prevention strategies for oral leukoplakia.

Clinical and Psychosocial Impact of Communication about Oral Potentially Malignant Disorders: A Scoping Review

Delivering bad news has been widely studied in cancer, thus, this scoping review aims to identify the available evidence concerning the communication of oral potentially malignant disorders (OPMDs) and their clinical and psychosocial impacts. A search was performed using electronic databases (Medline/PubMed, Scopus, Embase, and Web of Science) and one grey literature database (Google Scholar). Studies focused on communicating the diagnosis of OPMDs and the patients' perceptions were included. Study selection and data extraction were performed by two authors in a two-phase process. Five publications were included in the qualitative analysis. Differences regarding the study design, population, OPMDs assessed, and outcomes of professional-patient communication were found in each study. Protocols for OPMD communication have not yet been reported and there is a need to standardize strategies as communication skills may provide better clinical outcomes for patients diagnosed with potentially malignant disorders. Although future studies are needed, a brief list recommending the aspects that must be communicated is proposed.

Knockdown of PGC1α suppresses dysplastic oral keratinocytes proliferation through reprogramming energy metabolism

Oral potentially malignant disorders (OPMDs) are precursors of oral squamous cell carcinoma (OSCC). Deregulated cellular energy metabolism is a critical hallmark of cancer cells. Peroxisome proliferator-activated receptor-gamma coactivator-1 alpha (PGC1α) plays vital role in mitochondrial energy metabolism. However, the molecular mechanism of PGC1α on OPMDs progression is less unclear. Therefore, we investigated the effects of knockdown PGC1α on human dysplastic oral keratinocytes (DOKs) comprehensively, including cell proliferation, cell cycle, apoptosis, xenograft tumor, mitochondrial DNA (mtDNA), mitochondrial electron transport chain complexes (ETC), reactive oxygen species (ROS), oxygen consumption rate (OCR), extracellular acidification rate (ECAR), and glucose uptake. We found that knockdown PGC1α significantly inhibited the proliferation of DOKs in vitro and tumor growth in vivo, induced S-phase arrest, and suppressed PI3K/Akt signaling pathway without affecting cell apoptosis. Mechanistically, downregulated of PGC1α decreased mtDNA, ETC, and OCR, while enhancing ROS, glucose uptake, ECAR, and glycolysis by regulating lactate dehydrogenase A (LDHA). Moreover, SR18292 (an inhibitor of PGC1α) induced oxidative phosphorylation dysfunction of DOKs and declined DOK xenograft tumor progression. Thus, our work suggests that PGC1α plays a crucial role in cell proliferation by reprograming energy metabolism and interfering with energy metabolism, acting as a potential therapeutic target for OPMDs.

Polymorphonuclear myeloid-derived suppressor cells and phosphatidylinositol-3 kinase gamma are critical to tobacco-mimicking oral carcinogenesis in mice

BACKGROUND

Oral squamous cell carcinoma (OSCC) is a devastating disease most often associated with tobacco consumption that induces a field of mutations from which a tumor arises. Identification of ways to prevent the emergence of cancer in high-risk patients is an ultimate goal for combatting all types of cancer, including OSCC.

METHODS

Our study employs a mouse model of tongue carcinogenesis induced by tobacco carcinogen mimetic, 4-nitroquinoline 1-oxide (4NQO), to establish tongue dysplasia and OSCC. We use conventional histology, immunohistochemistry, multispectral imaging, mass cytometry, novel cell lines, pharmaceutical inhibition of PI3Kγ, T-cell suppression assays and mouse transplant models in our functional experimentation.

RESULTS

In our study, we identify Ly6G+ granulocytes as the most abundant immune cell type in a model of tongue carcinogenesis induced by tobacco carcinogen mimetic 4NQO. Targeting Ly6G+ granulocytes with a pharmacologic inhibitor of PI3Kγ, an isoform of PI3K exclusively expressed by myeloid cells, resulted in reduced tongue dysplasia severity, and reduced rates of OSCC. Importantly, we performed functional assays with the Ly6G+ granulocytes induced in cell line models of 4NQO carcinogenesis to demonstrate that these granulocytes have increased polymorphonuclear myeloid-derived suppressor cells (PMN-MDSC) activity against T-cell proliferation and these PMN-MDSCs play a functional role in promoting tumor formation by inhibiting tumor regression in a PI3Kγ-dependent manner.

CONCLUSIONS

Overall, our data suggest that recruitment of PMN-MDSCs to sites of dysplasia is critical to immune suppression of CD8 T cells, thereby permitting malignancy, and PI3Kγ inhibitors are one mechanism to reduce PMN-MDSC recruitment, immunosuppression and tumorigenesis in OSCC.

Pan-American prevalence of smokeless tobacco use and association with oral potentially malignant disorders and head and neck cancer: a systematic review and meta-analysis

OBJECTIVES

To determine the prevalence of smokeless tobacco (SLT) use and its association with oral potentially malignant disorders (OPMDs) and head and neck cancer (HNC) in the Pan-American Health Organization (PAHO) region.

STUDY DESIGN

A literature search was conducted across 9 databases and other sources. The eligibility criteria were pediatric (0-18 years old) and adult (19 years and older) populations consuming any type of SLT. Meta-analysis was performed to determine the prevalence of SLT and the association between its use and OPMDs/HNC in the PAHO region; the Grading of Recommendations Assessment, Development, and Evaluation tool was used to verify the certainty of evidence.

RESULTS

Fifty-nine studies from 6 PAHO countries were included, of which 51 were also subjected to quantitative analysis. The pooled SLT prevalence of use was 15% (95%CI: 11.93-18.69) overall, 17% (95%CI: 13.25-22.65) in adults, and 11% (95%CI: 8.54-14.78) in the pediatric population. The highest reported SLT prevalence of use was 33.4% (95%CI: 27.17-39.93) in Venezuela. HNC was positively associated with SLT use (OR = 1.98, 95%CI: 1.54-2.55), with a moderate certainty of evidence. Among OPMDs, only leukoplakia reported a positive association with SLT use (OR = 8.38; 95%CI: 1.05-67.25). However, the quality of the evidence was very low.

CONCLUSION

A high consumption of SLT use, chewing tobacco and snuff, is reported among the adult population residing in the PAHO region with a positive association with the development of oral leukoplakia and HNC.

Photodynamic therapy (PDT) for oral leukoplakia: a systematic review and meta-analysis of single-arm studies examining efficacy and subgroup analyses

OBJECTIVE

This study aims to evaluate the efficacy of photodynamic therapy (PDT) in the treatment of oral leukoplakia and explore the subgroup factors that may influence its effectiveness.

METHODS

A systematic search was conducted in PubMed, Embase, the Cochrane Library, and Web of Science databases to identify relevant studies. Meta-analysis was performed using Stata15.0 software. Cochran's Q test and I2 statistics were used to evaluate heterogeneity, egger's test was used to evaluate publication bias.

RESULTS

The analysis of 17 studies included in this study suggests that PDT may be effective in achieving complete response (CR) [ES = 0.50, 95%CI: (0.33,0.66)], partial response (PR) [ES = 0.42, 95%CI: (0.27,0.56)], no response (NR) [ES = 0.19, 95%CI: (0.11,0.27)]in patients with oral leukoplakia. The recurrence rate was also evaluated [ES = 0.13, 95%CI: (0.08,0.18)]. Subgroup analysis showed that various factors such as light source, wavelength, medium, duration of application, clinical and pathological diagnosis classification influenced efficacy of PDT. The lesion areas of the leukoplakia after treatment were reduced by 1.97cm2 compared with those before treatment.

CONCLUSION

Our findings show that PDT is a viable treatment for oral leukoplakia. However, the effectiveness of the therapy may depend on several factors, as suggested by our subgroup analyses. (Registration no. CRD42023399848 in Prospero, 26/02/2023).

Predictive value of CDKN2A/p16INK4a expression in the malignant transformation of oral potentially malignant disorders: Systematic review and meta-analysis

BACKGROUND

Management of oral potentially malignant disorders (OPMDs) is still challenging. Despite the diagnostic ascertainment by bioptic examination, this method is poorly informative of the prognosis and subsequent malignant transformation. Prognosis is based on histological findings by grading of dysplasia. Immunohistochemical expression of p16INK4a has been investigated in different studies, with controversial results. In this scenario, we systematically revised the current evidence about p16INK4a immunohistochemical expression and the risk of malignization of OPMDs.

MATERIAL AND METHODS

After a proper set of keywords combination, 5 databases were accessed and screened to select eligible studies. The protocol was previously registered on PROSPERO (Protocol ID: CRD42022355931). Data were obtained directly from the primary studies as a measure to determine the relationship between CDKN2A/P16INK4a expression and the malignant transformation of OPMDs. Heterogeneity and publication bias were investigated by different tools, such as Cochran's Q test, Galbraith plot and Egger and Begg Mazumdar's rank tests.

RESULTS

Meta-analysis revealed a twofold increased risk to malignant development (RR = 2.01, 95% CI = 1.36-2.96 - I2 = 0%). Subgroup analysis did not highlight any relevant heterogeneity. Galbraith plot showed that no individual study could be considered as an important outlier.

CONCLUSION

Pooled analysis showed that p16INK4a assessment may arise adjunct tool to dysplasia grading, leading to an optimized determination of the potential progression to cancer of OPMDs. The p16INK4a overexpression analysis by immunohistochemistry techniques has a multitude of virtues that may facilitate its incorporation in the day-to-day prognostic study of OPMDs.

Acquisition and annotation in high resolution in vivo digital biopsy by confocal microscopy for diagnosis in oral precancer and cancer

Introduction

Scanned fibre endomicroscopes are full point-scanning confocal microscopes with submicron lateral resolution with an optical slice thickness thin enough to isolate individual cell layers, allow active positioning of the optical slice in the z-axis and collection of megapixel images. Here we present descriptive findings and a brief atlas of an acquisition and annotation protocol high resolution in vivo capture of oral mucosal pathology including oral squamous cell carcinoma and dysplasia using a fluorescence scanned fibre endomicroscope with 3 topical fluorescent imaging agents: fluorescein, acriflavine and PARPi-FL.

Methods

Digital biopsy was successfully performed via an acquisition protocol in seventy-one patients presenting for investigation of oral mucosal abnormalities using a miniaturized, handheld scanned fibre endoscope. Multiple imaging agents were utilized and multiple time points sampled. Fifty-nine patients had a matched histopathology correlating in location with imaging. The images were annotated back to macrographic location using a purpose-built software, MouthMap™.

Results

Acquisition and annotation of cellular level resolved images was demonstrated with all 3 topical agents. Descriptive observations between clinically or histologically normal oral mucosa showed regular intranuclear distance, a regular nuclear profile and fluorescent homogeneity. This was dependent on the intraoral location and type of epithelium being observed. Key features of malignancy were a loss of intranuclear distance, disordered nuclear clustering and irregular nuclear fluorescence intensity and size. Perinuclear fluorescent granules were seen in the absence of irregular nuclear features in lichenoid inflammation.

Discussion

High resolution oral biopsy allows for painless and rapid capture of multiple mucosal sites, resulting in more data points to increase diagnostic precision. High resolution digital micrographs can be easily compared serially across multiple time points utilizing an annotation software. In the present study we have demonstrated realization of a high-resolution digital biopsy protocol of the oral mucosa for utility in the diagnosis of oral cancer and precancer..

Management of oral leukoplakia with an 808-nm high-power diode laser: a single-center experience

PURPOSE

High-power diode laser emerges as a promising approach to the treatment of oral leukoplakia (OL); however, its short- and long-term effects have been barely explored. This study evaluated the postoperative endpoints and the recurrence rate of high-power diode laser treatment in a well-defined series of patients with OL.

METHODS

A prospective analysis was performed on 22 individuals comprising 31 OL. The lesions were irradiated using the following protocol: Indium-Gallium-Arsenide diode laser, 808 nm, continuous-wave mode, 1.5-2.0 W, 780.0 ± 225.1 J, and 477.1 ± 131.8 s. Postoperative pain was assessed with a visual analog scale at three endpoints. Clinical follow-up was performed on all patients and the Kaplan-Meier test was used to analyze the probability of recurrence.

RESULTS

The series consisted mostly of women (72.7%) with a mean age of 62.8 years. A single laser session was performed in 77.4% of cases. The median score on the scale that assessed pain on the 1st, 14th and 42nd postoperative day was 4, 1, and 0, respectively. The mean follow-up period per lesion was 28.6 months (range: 2-53 months). A complete response was observed in 93.5% of OL cases, while 6.5% had recurrence. The probability of recurrence at 39 months was 6.7%. No patient experienced malignant transformation.

CONCLUSION

High-power diode laser for the treatment of OL is safe and effective during the trans- and postoperative period. These findings represent an alternative approach to the management of OL, mainly because a low recurrence rate was observed.

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.

Biomarkers of malignant transformation in oral leukoplakia: from bench to bedside

Oral leukoplakia is a common precursor lesion of oral squamous cell carcinoma, which indicates a high potential of malignancy. The malignant transformation of oral leukoplakia seriously affects patient survival and quality of life; however, it is difficult to identify oral leukoplakia patients who will develop carcinoma because no biomarker exists to predict malignant transformation for effective clinical management. As a major problem in the field of head and neck pathologies, it is imperative to identify biomarkers of malignant transformation in oral leukoplakia. In this review, we discuss the potential biomarkers of malignant transformation reported in the literature and explore the translational probabilities from bench to bedside. Although no single biomarker has yet been applied in the clinical setting, profiling for genomic instability might be a promising adjunct.

Developmental synergism in the management of oral potentially malignant disorders

Oral potentially malignant disorders (OPMDs) are associated with an increased risk of occurrence of cancers of the oral cavity or lips. The unifying theme of OPMDs is their potential risk for cancer development. Therefore, the primary objective of the management should be to prevent carcinogenesis. Beyond diagnosis, current strategies for the management of OPMDs predominantly include non-surgical and surgical interventions and a "watch-and-see" approach, such as disease monitoring or surveillance, and preventive strategies. Though no optimal clinical treatment has gained universal approval for reducing or preventing malignant development of OPMDs. Therefore, an urgent need exits for improved treatment properties and effective predictive markers for OPMDs treatment. This review aims to outline recent synergism regarding to the management of OPMDs. Developing new technologies and improved application parameters to promote the treatment efficacy and a novel management prescription approach to OPMDs are proposed.

Diagnosis of oral potentially malignant disorders: Overview and experience in Oceania

The diagnosis and management of oral potentially malignant disorders (OPMD) should be the same the world over, but there are important nuances in incidence, aetiological factors, and management opportunities that may lead to differences based on ethnogeography. In this review, we update and discuss current international trends in the classification and diagnosis of OPMD with reference to our experience in various regions in Oceania. Oceania includes the islands of Australia, Melanesia (including Papua New Guinea, Fiji, Solomon Islands, Micronesia and Polynesia (including New Zealand, Samoa, Tonga) and hence has diverse populations with very different cultures and a range from well-resourced high-population density cities to remote villages.

Prevalence and determinants of oral potentially malignant disorders in rural areas of South India

Purpose

Oral potentially malignant disorders are associated with a risk of undergoing malignant transformation and a concomitant increase in morbidity and mortality. Moreover, epidemiological studies, especially from rural areas, are important in assessing their prevalence and the identification of determinants of these disorders so that preventive strategies can be employed in tackling them.

Methods

Cross-sectional descriptive study was conducted based on guidelines of the World Health Organization's Guide Epidemiology and Diagnosis of Oral Mucosal Disease and Conditions 1995 in rural areas of south India.

Results

Prevalence of oral potentially malignant disorders (OPMDs) in the studied population was 13.28%, with oral submucous fibrosis (OSMF) accounting to 6.21% and erythroplakia at 1.3%. Regression analysis revealed, age 40-54 years (odds ratio [OR] = 3.8, confidence interval [CI] at 95%-1.5-4.0, P < 0.05), lower socioeconomic groups (OR = 2.1, CI at 95%-1.4-3.1, P < 0.05), habits (OR = 3.2, CI at 95%-1.9-3.8, P < 0.05), smoke form of tobacco-beedi (OR = 2.5, CI at 95%-1.6-2.8, P < 0.05), smokeless form of tobacco-areca nut lime and leaf and tobacco (OR = 3.1, CI at 95%-1.9-3.4, P < 0.05) to be the possible determinants for OPMDs.

Conclusions

The overall prevalence of OPMDs in the studied population was 13.28%. The most common OPMDs were OSMF. Identified determinants were age, socioeconomic group, ethnicity, diet, body mass index, and associated harmful habits.

Occurrence of Second Oral Potentially Malignant Disorder following Excision of Primary Lesion: A Prospective Study of Cases from a Tertiary Care Centre

Background

Early diagnosis and timely management of potentially malignant oral disorders may prevent malignant transformation and prompt diagnosis of frank malignancies favours better prognosis. The aim of this study was to evaluate the outcome of surgical management of oral potentially malignant disorders of the oral cavity and observe the prevalence of recurrence at the primary site and occurrence of another potentially malignant lesion in these patients.

Methods

The study participants included patients who had undergone clinical oral examination, surgical excision of biopsy-proven cases of dysplastic oral potentially malignant disorders (leukoplakia, erythroplakia, non-healing ulcerative and erosive areas, etc.) who were on routine follow-up as per the standard guidelines. These patients were followed up closely during each monthly follow-up visit for the first year. The patients were then prospectively analysed for any recurrence of lesion. On follow-up visits, detailed clinical oral examination was done to note the prevalence of a new lesion in any oral cavity sub site other than the previous site. If a new lesion was detected, then biopsy followed by surgical excision was followed as per standard guidelines. The follow-up period after the second surgical intervention was 12 months.

Results

Fifty patients with potentially malignant oral disorders underwent surgical excision. The majority of the study subjects were males (39/50) and 41 of them were below 65 years of age. Of 50 patients, 13 (26%) had second oral potentially malignant lesion other than the primary site. The rate of recurrence of the lesions at the primary site was 4% (2/50). Of these patients with recurrence, all had malignant transformation (2/2). Also, patients who were initially diagnosed with moderate dysplasia had a higher chance of recurrence. A second lesion at a site different from the primary lesion was seen in 26% of the cases.

Conclusion

Surgical management of such lesions with one-centimetre oncological margins in all dimensions contrary to the routine five millimetre surgical margins reduces the chance of recurrence.