IARC Perspective on Oral Cancer Prevention

A prospective study on diagnostic accuracy of technology-enabled early detection of oral cancer and epidemiology of tobacco and other substances use in rural India

BACKGROUND

Lip and oral cavity cancer is leading cause of cancer mortality among Indian men. This study evaluated diagnostic accuracy of mobile health (mHealth) enabled screening for early detection of oral premalignant lesions or oral cancer (OPML/OC). It also described epidemiology of tobacco and other substance use and associated oral lesions in rural northern India.

METHODS

A prospective study enrolled 10,101 high-risk individuals from rural settings of Varanasi district, India, between February 2021 and June 2023. Trained field workers captured habits information and oral cavity images and provided screening as suspicious or nonsuspicious on mHealth. Onsite experts and remote specialists provided clinical diagnoses. Diagnostic accuracy of mHealth-enabled screening was evaluated. A subset of 252 participants was followed to assess changes in oral lesions.

RESULTS

Prevalence of substance use was 55.7%, with 21.4% having OPML/OC. Sensitivity of field workers and remote diagnosis for detecting OPML/OC was moderate when compared with onsite expert. Overall, interobserver agreement was substantial. During follow-up, the remote specialists identified 30 new and 13 progressive lesions with a significant decline in the red mean parameter of red, green, and blue colour ratios.

CONCLUSION

Although mHealth-enabled screening demonstrated lower sensitivity in detecting OPML/OC, their high specificity and expanded access to screening positions mHealth as a valuable tool for improving oral cancer screening coverage in Varanasi. This is particularly crucial given the high burden of oral cancer driven by prevalent smokeless tobacco and areca nut use and the current lack of effective population-based screening programs in this region.

Prognostic Factors in Head and Neck Cancer: A Retrospective Cohort Study of 3052 Patients in Brazil

OBJECTIVE

Evaluate the sociodemographic, clinical, and lifestyle characteristics at head and neck squamous cell carcinoma (HNSCC) diagnosis and their impact on overall survival (OS) across different anatomical sites.

MATERIALS AND METHODS

A retrospective cohort study (2011-2021) at Instituto do Câncer do Estado de São Paulo, involving 3052 HNSCC patients. Survival analyses utilized the Kaplan-Meier method and Cox proportional hazard ratios with 95% confidence intervals, incorporating significant variables from univariate analysis.

RESULTS

The five-year OS for all HNSCC sites (n = 3052) was 31.4%, with specific rates of 37.0% for laryngeal cancer (n = 935), 35.8% for oral cancer (n = 762), 26.6% for oropharyngeal cancer (OPC) (n = 1189), and 14.8% for hypopharyngeal cancer (n = 166). HPV-positive OPC had a higher five-year OS (59.3%; n = 127) compared to HPV-negative (35.4%; n = 226). Multivariable analysis identified older age (≥ 70 years) and advanced TNM stage (IV) as adverse prognostic factors for oral cavity, oropharynx, and larynx sites. Male gender was associated with poorer prognosis in the oral cavity, while alcohol consumption was linked to worse outcomes in oropharynx and larynx sites.

CONCLUSION

HNSCC OS remains low at a public cancer center in São Paulo. Older age, advanced tumor stage, and alcohol consumption are independent adverse prognostic factors, particularly in oropharynx and larynx sites.

miRNA-199b-5p suppresses of oral squamous cell carcinoma by targeting apical-basolateral polarity via Scribble/Lgl

In epithelial cells, Scribble forms cell-cell junctions and contributes to cell morphology and homeostasis by regulating apical-basolateral polarity in mammals and functions as a tumor suppressor in many carcinomas. The initial diagnosis of oral squamous cell carcinoma is important, and its prognosis is poor when accompanied by metastasis. However, research on the mechanisms of oral squamous cell carcinoma metastasis is insufficient. Herein, we showed that Scribble regulates the apical-basolateral polarity of oral squamous cell carcinoma by regulating lethal giant larvae 1, Scribble module and E-cadherin, the adhesion junction. The expression of lethal giant larvae 1 and E-cadherin decreased when the expression of Scribble was knocked down and their localization was completely disrupted in both the oral squamous cell carcinoma cell line and in vivo model. In particular, the Scribble was involved in oral squamous cell carcinoma metastasis via hsa-miR-199b-5p, which is a microenvironmental factor of hypoxia. The disruption of Scribble localization under hypoxic conditions, but its localization was maintained in miR-199b-5p oral squamous cell carcinoma cell lines and in vivo. These results suggest that Scribble functions as a tumor suppressor marker mediated by miR-199b-5p in oral squamous cell carcinoma.

Estimating the Benefits of Oral Cancer Screening: Challenges and Opportunities

Screening is widely believed to facilitate early detection and improve health outcomes; however, recent evidence questions its overall benefits, highlighting the need for a critical assessment of cancer screening programs. The simplicity of clinical oral examination and the easy accessibility of the oral cavity make oral cancer a suitable candidate for opportunistic screening. Despite this uniqueness, studies that solidly assess the efficacy and cost-effectiveness of oral cancer screening are scanty, and the only large randomized trial undertaken so far shows limited evidence of mortality reduction through population screening. Research indicates that while early detection rates following screening may increase, they do not necessarily translate into decreased oral cancer deaths. This article emphasizes the need for a nuanced understanding of the benefits of screening, awareness of deceptive metrics and inherent biases in the context of early detection, and the importance of improving dentist education and introducing new technologies to enhance clinical decision-making. The review calls for a balanced and evidence-based approach to oral cancer screening, integrating it with broader oral health initiatives to maximize public health outcomes.

Autophagy in oral cancer: Promises and challenges (Review)

Autophagy captures damaged or dysfunctional proteins and organelles through the lysosomal pathway to achieve proper cellular homeostasis. Autophagy possesses distinct characteristics and is given recognized functions in numerous physiological and pathological conditions, such as cancer. Early stage cancer development can be stopped by autophagy. After tumor cells have successfully undergone transformation and progressed to a late stage, the autophagy-mediated system of dynamic degradation and recycling will support cancer cell growth and adaptation to various cellular stress responses while preserving energy homeostasis. In the present study, the dual function that autophagy plays in various oral cancer development contexts and stages, the existing arguments for and against autophagy, and the ways in which autophagy contributes to oral cancer modifications, such as carcinogenesis, drug resistance, invasion, metastasis and self-proliferation, are reviewed. Special attention is paid to the mechanisms and functions of autophagy in oral cancer processes, and the most recent findings on the application of certain conventional drugs or natural compounds as novel agents that modulate autophagy in oral cancer are discussed. Overall, further research is needed to determine the validity and reliability of autophagy promotion and inhibition while maximizing the difficult challenge of increasing cancer suppression to improve clinical outcomes.

"Exploring the Link Between Oral Lichen Planus and Xerostomia: A Systematic Literature Review"

INTRODUCTION

Oral lichen planus (OLP) is a chronic disorder affecting the oral mucosa, potentially associated with xerostomia, either independently or concurrently. Research suggests that approximately 45% of patients with erythematous and ulcerative OLP may experience dry mouth sensations. The aim of this systematic review is to assess the current literature regarding the potential relationship or co-occurrence of xerostomia with OLP. Understanding this association is imperative for the development of comprehensive management strategies and the improvement of patient outcomes.

METHOD AND MATERIAL

The study followed the PRISMA 2020 checklist and included human studies, specifically investigating xerostomia in patients with OLP. After screening 897 articles, 9 studies were selected based on predefined criteria Quality assessment was conducted using the Cochrane risk of bias tools: ROB 2 for RCTs and ROBINS-I for non-randomized studies Scale was conducted to evaluate potential biases in study design, selection, and outcomes.

RESULT

A systematic review of nine studies (1960-2023) examining xerostomia in OLP patients found a significant reduction in unstimulated salivary flow rates in many cases. Although evidence links xerostomia with OLP, a definitive causal relationship remains unestablished. Some studies highlighted Candida infection, altered saliva protein expression, and inflammation-related nerve damage as contributing factors to dry mouth in OLP patients.

DISCUSSION AND CONCLUSION

This systematic review examines the potential relationship between OLP and xerostomia, focusing on factors such as salivary flow, histopathological changes, and immune-related mechanisms. While some studies suggest a link between OLP and reduced saliva production, no definitive causal relationship has been established. The review identified significant research gaps, including inconsistent methodologies and a lack of standardized criteria. Future studies should explore different OLP forms, receptor interactions, immune responses, and neuropeptides to gain a better understanding of xerostomia's etiopathogenesis and improve management strategies for OLP patients.

Influence of Health System Affiliation and Pain Manifestation on Advanced Oral Cavity Squamous Cell Carcinoma Risk: A Retrospective Cohort Study in a Latin American Population

Background/Objectives: Oral cavity cancer, a subtype of head and neck cancer, is one of the most common malignancies globally. This study assessed the influence of health system affiliation and pain manifestation on the risk of advanced oral cavity squamous cell carcinoma (OCSCC) in a Latin American population. Methods: In this retrospective cohort study, we analyzed medical records from 2015 to 2016, including data from the past 19 years, of 233 patients with OCSCC treated at a public hospital in Medellín, Colombia. Sociodemographic and clinical variables were evaluated, and multivariate regression models incorporated variables significant in bivariate analysis. Results: Among 233 patients, 196 (84.1%) had advanced OCSCC. The sample had a mean age of 63 ± 13 years, 53.6% were male, and 64% came from urban areas with predominantly low socioeconomic levels. Men showed a threefold increased risk of advanced OCSCC (95% CI: 1.3-6.8), while patients referred to pain clinics exhibited a 19.5 times higher risk (95% CI: 2.3-159.5). Patients in the subsidized health system or without health insurance had 2.6 (95% CI: 1.07-6.3) and 2.7 times (95% CI: 1.17-6.4) higher risks, respectively. Conclusions: This study found that male patients, referrals to pain clinics, and subsidized or no health system affiliation significantly increased the risk of advanced OCSCC.

Functional Rehabilitation in Non-Reconstructed Hemimandibulectomy Patients

Background and Objectives: Functional rehabilitation in patients with hemimandibulectomy remains a challenge no matter what method of reconstruction is chosen by physicians. In this paper, we aim to evaluate the feasibility of an acceptable occlusal restoration in patients who have undergone hemimanidublectomy without the reestablishment of mandibular continuity. Materials and Methods: Data were collected retrospectively on 10 patients with varying degrees of mandible resection. The greatest challenge in the restoration of an acceptable occlusion form is the natural latero-deviation that occurs in patients whose mandibular continuity was not restored. This causes an unbalanced and uncoordinated occlusal plane. Based on our research, this deviation is highly dependent on three main factors: the presence of teeth (which allow for a proprioceptive stimulus that counteracts the deviation), the extension of the defect and the presence or lack of the coronoid process. Results: Based on the presence of dental elements or lack thereof, patients were either rehabilitated with implant-supported dentures or removable partial dentures. Although the gold standard of care for these patients remains the restoration of mandible continuity through use of bone grafts, an acceptable rehabilitation of occlusion and therefore function may be acquired in non-grafted patients. Conclusions: Both physicians and patients must manage their expectations carefully and be eager to find a compromise to provide the best possible solution given the challenges of the premises.

Decoding lymphangiogenesis in oral squamous cell carcinoma: Emphasis on clinical and histopathological determinants of regional metastasis

PURPOSE

The growth and metastasis of solid epithelial tumors is lymphangiogenesis dependent. The most important lymphangiogenic inducers facilitating this progression is Vascular endothelial Growth Factor C (VEGF-C). The recent D2-40 (Podoplanin) antibody is specific for lymphatic epithelium and allows its objective assessment. Also, lymphovascular invasion (LVI) is a risk factor for lymph node metastases (LNM) and indicates a significant influx of tumor cells into the lymphatics, causing regional metastasis. Thus, the following study was conducted to assess and correlate VEGF-C and D2-40 immunoexpressions with clinical and histopathologic lymph node status in Oral Squamous Cell Carcinoma (OSCC) cases and also to estimate the impact of intratumoral (ILVD) and peritumoral lymphatic vessel density (PLVD) in such cases.

METHODOLOGY

A total of 128 OSCC cases, divided as Group I: Cases with clinically and histopathologically negative lymph nodes (n = 64) and Group II: Cases with clinically negative but histopathologically positive lymph nodes (n = 64) were immunoscored for VEGF-C (Anti VEGF-C antibody) (PA5-29772, Invitrogen) and D2-40 (Anti D2-40 antibody) (IR072/8072, Dako) using standard protocols. The data was statistically evaluated using STATA 18.0 with p≤0.05 considered statistically significant throughout the study.

RESULT

21.88% Group I cases and 40.62% Group II cases showed highest immuno-positivity for VEGF-C (p = 0.00). The mean D2-40 score for Intratumoral Lymphatic Vessel Density (ILVD) and Peritumoral Lymphatic Vessel Density (PLVD) was higher for group II cases (i.e., 41.5±13.73 and 35.95±8.27 respectively at 95% CI, p = 0.00) suggesting a direct correlation between Lymphatic Vessel Density (LVD) and LNM.

CONCLUSION

Lymphangiogenesis is a true determinant of the biologic potential of OSCC and obtaining an objective data in terms of LVD through D2-40 could be impactful in OSSC diagnosis and guiding treatment decisions by clinicians.

Needs assessment for interprofessional education module on prevention and early detection of oral cancer among dental interns: a cross- sectional survey

BACKGROUND

The challenges associated with ensuring widespread system changes to enable early diagnosis and prevention of oral cancer could benefit from interprofessional practice. A needs assessment study was conducted to inform the Interprofessional Education and Collaborative Practice (IPECP) course related to oral cancer. The primary objectives of this study were 1) to establish a tool assess the knowledge attitude and practice (KAP) related to prevention and early detection of oral cancer of health professional students, and 2) to assess the same KAP of pre-licensure dental students. Additional objectives were to consider the possibility that dental students would demonstrate good scores related to early detection and prevention of oral cancer thus indicating their readiness for interprofessional learning and collaborative practice.

METHODS

Two questionnaires were utilized for this study which included 1) Readiness for interprofessional learning was assessed using the pre- validated tool of Readiness for Interprofessional Learning Scale (RIPLS) 2) A questionnaire to assess the KAP related to early diagnosis and prevention of oral cancer which was developed, validated, and evaluated. Statistical analysis includes, descriptive statistics, Mann-Whitney U test, Ordered logistic regression and Probit analysis. p value was set at < 0.05.

RESULTS

A total of 130 dental students (74.6% female) were included in the study. Mean scores related to KAP were 15.96 ± 1.394, 4.70 + 1.146, 7.02 ± 1.019 respectively. The mean score of RIPLS was 73.15 ± 15.961. The probability of overall samples to have good RIPLS scores was around 0.68 to 0.76 (Male 0.68-0.82 & Female 0.68 -0.74). The percentage of students having good knowledge score was 93.8%, good attitude score was around 54.6% and good practice score was around 90%.

CONCLUSION

Knowledge and practice related to prevention and early detection of oral cancer were scored highly. Attitude scores were lower in a relatively higher proportion of participants and needed to be addressed in the curriculum. RIPLS score indicates a positive attitude towards interprofessional learning.

Isolation and phenotypic characterization of cancer stem cells from metastatic oral cancer cells

OBJECTIVES

To isolate cancer stem cells (CSC) from a metastatic oral squamous cell carcinoma (OSCC) cell line and investigate their in vitro and in vivo phenotypic characteristics.

MATERIALS AND METHODS

Subpopulations with individual staining intensities for CD44 and CD326 were isolated from the OSCC cell line LN-1A by FACS: CD44Low/CD326- (CSC-M1), CD44Low/CD326High (CSC-E), and CD44High/CD326- (CSC-M2). Proliferation, clonogenic potential, adhesion, migration, epithelial-mesenchymal transition markers, and sensitivity to cisplatin and TVB-3166 were analyzed in vitro. Tumor formation and metastasis were assessed by subcutaneous and orthotopic inoculations into BALB/c mice.

RESULTS

E-cadherin levels were higher in CSC-E cells while vimentin and Slug more produced by CSC-M2 cells. CSC-M1 and CSC-M2 subpopulations showed higher proliferation, produced more colonies, and have stronger adhesion to the extracellular matrix. All cell lines established tumors; however, CSC-E and CSC-M2 formed larger masses and produced more metastases.

CONCLUSION

The CSC subpopulations here described show increased cancer capabilities in vitro, tumorigenic and metastatic potential in vivo, and may be exploited in the search for novel therapeutic targets for OSCC.

Design of probiotic delivery systems and their therapeutic effects on targeted tissues

The microbiota at different sites in the body is closely related to disease. The intake of probiotics is an effective strategy to alleviate diseases and be adjuvant in their treatment. However, probiotics may suffer from harsh environments and colonization resistance, making it difficult to maintain a sufficient number of live probiotics to reach the target sites and exert their original probiotic effects. Encapsulation of probiotics is an effective strategy. Therefore, probiotic delivery systems, as effective methods, have been continuously developed and innovated to ensure that probiotics are effectively delivered to the targeted site. In this review, initially, the design of probiotic delivery systems is reviewed from four aspects: probiotic characteristics, processing technologies, cell-derived wall materials, and interactions between wall materials. Subsequently, the review focuses on the effects of probiotic delivery systems that target four main microbial colonization sites: the oral cavity, skin, intestine, and vagina, as well as disease sites such as tumors. Finally, this review also discusses the safety concerns of probiotic delivery systems in the treatment of disease and the challenges and limitations of implementing this method in clinical studies. It is necessary to conduct more clinical studies to evaluate the effectiveness of different probiotic delivery systems in the treatment of diseases.

Epidemiology of oral cancer in South and South-East Asia: Incidence and mortality

INTRODUCTION

This study provides an epidemiological description of cancer in the lip, oral cavity, and oropharynx in the South and South-East Asia region.

METHODS

The number of new cases and deaths was extracted from the GLOBOCAN 2020 and the CI5 series. We present age-standardized incidence and mortality rates per 100,000 inhabitants. To assess temporal trends, we estimated the annual percent change.

RESULTS

The incidence rates (ASR) for lip and oral cavity cancer in South and South-East Asia were highest in Taiwan (30.2), Sri Lanka (16.5), India (14.8), and Pakistan (13.2) among males. For oropharyngeal cancer, the highest rates were found in Taiwan (4.7), Bangladesh, Sri Lanka, and India (4.3, 2.9, and 2.6, respectively). Incidence rates were consistently higher in males compared to females. Overall, trends in lip and oral cavity cancer incidence were either stable or decreasing in most of the populations evaluated. In India, an increase in rates among males contrasted with a decline among females over the study period.

CONCLUSION

Incidence and mortality rates of oral cavity cancer in South and South-East Asia are among the highest globally. Our results suggest an optimistic trend of reduction in oral cavity rates in the region, despite an increase in rates among Indian males.

Molecular Targets of Plant-Derived Bioactive Compounds in Oral Squamous Cell Carcinoma

BACKGROUND

With a significant increase in both incidence and mortality, oral cancer-particularly oral squamous cell carcinoma (OSCC)-is one of the main causes of death in developing countries. Even though there is evidence of advances in surgery, chemotherapy, and radiotherapy, the overall survival rate for patients with OSCC has improved, but by a small percentage. This may be due, on the one hand, to the fact that the disease is diagnosed when it is at a too-advanced stage, when metastases are already present.

METHODS

This review explores the therapeutic potential of natural herbal products and their use as adjuvant therapies in the treatment of oral cancer from online sources in databases (PubMed, Web of Science, Google Scholar, Research Gate, Scopus, Elsevier).

RESULTS

Even if classic therapies are known to be effective, they often produce many serious side effects and can create resistance. Certain natural plant compounds may offer a complementary approach by inducing apoptosis, suppressing tumor growth, and improving chemotherapy effectiveness. The integration of these compounds with conventional treatments to obtain remarkable synergistic effects represents a major point of interest to many authors. This review highlights the study of molecular mechanisms and their efficiency in in vitro and in vivo models, as well as the strategic ways in which drugs can be administered to optimize their use in real contexts.

CONCLUSIONS

This review may have a significant impact on the oncology community, creating new inspirations for the development of more effective, safer cancer therapies with less toxic potential.

Molecular and cell phenotype programs in oral epithelial cells directed by co-exposure to arsenic and smokeless tobacco

Chronic arsenic exposure can lead to various health issues, including cancer. Concerns have been mounting about the enhancement of arsenic toxicity through co-exposure to various prevalent lifestyle habits. Smokeless tobacco products are commonly consumed in South Asian countries, where their use frequently co-occurs with exposure to arsenic from contaminated groundwater. To decipher the in vitro molecular and cellular responses to arsenic and/or smokeless tobacco, we performed temporal multi-omics analysis of the transcriptome and DNA methylome remodelling in exposed hTERT-immortalized human normal oral keratinocytes (NOK), as well as arsenic and/or smokeless tobacco genotoxicity and mutagenicity investigations in NOK cells and in human p53 knock-in murine embryonic fibroblasts (Hupki MEF). RNAseq results from acute exposures to arsenic alone and in combination with smokeless tobacco extract revealed upregulation of genes with roles in cell cycle changes, apoptosis and inflammation responses. This was in keeping with global DNA hypomethylation affecting genes involved in the same processes in response to chronic treatment in NOK cells. At the phenotypic level, we observed a dose-dependent decrease in NOK cell viability, induction of DNA damage, cell cycle changes and increased apoptosis, with the most pronounced effects observed under arsenic and SLT co-exposure conditions. Live-cell imaging experiments indicated that the DNA damage likely resulted from induction of apoptosis, an observation validated by a lack of exome-wide mutagenesis in response to chronic exposure to arsenic and/or smokeless tobacco. In sum, our integrative omics study provides novel insights into the acute and chronic responses to arsenic and smokeless tobacco (co-)exposure, with both types of responses converging on several key mechanisms associated with cancer hallmark processes. The generated rich catalogue of molecular programs in oral cells regulated by arsenic and smokeless tobacco (co-)exposure may provide bases for future development of biomarkers for use in molecular epidemiology studies of exposed populations at risk of developing oral cancer.

Biomarkers in head and neck squamous cell carcinoma: unraveling the path to precision immunotherapy

Recent strides in understanding the molecular underpinnings of head and neck cancers have sparked considerable interest in identifying precise biomarkers that can enhance prognostication and enable personalized treatment strategies. Immunotherapy has particularly revolutionized the therapeutic landscape for head and neck squamous cell carcinoma, offering new avenues for treatment. This review comprehensively examines the application and limitations of the established and emerging/novel biomarkers for head and neck squamous cell carcinoma. Established biomarkers, including well-characterized genetic mutations, protein expressions, and clinical factors, have been extensively studied and validated in clinical practice. Novel biomarkers identified through molecular analyses, including novel genetic alterations, immune-related markers, and molecular signatures, are currently being investigated and validated in preclinical and clinical settings. Biomarkers hold the potential to deepen our understanding of head and neck squamous cell carcinoma biology and guide therapeutic strategies. The evolving paradigm of predictive biomarkers facilitates the study of individual responses to specific treatments, including targeted therapy and immunotherapy.

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.

Head and Neck Cancer in Pan-American Notable People: An International Survey

Background: The study of notable people as advocates for raising cancer awareness began in the latter decades of the 20th century. This research aimed to identify Pan-American notable people with head and neck cancer (HNC) and to explore senior health professionals' perspectives on communicating stories of notable patients with HNC to promote prevention. Method: A cross-sectional survey was conducted using an online questionnaire designed in REDCap and administered to 32 senior health professionals with long-standing academic and clinical backgrounds in HNC. In addition, a structured literature review was performed on PubMed, Scopus, EMBASE, Web of Science, LILACS, and gray literature. Results: 18 notable figures were successfully identified from the survey, and 24 from the literature review. These individuals came from the United States, Brazil, Argentina, Mexico, El Salvador, Chile, Colombia, and Peru, and were recognized primarily for their performances as actors, artists, musicians, and athletes. The professionals' outlooks were positive, with 31 (96.9%) agreeing that disseminating these stories can contribute to reducing risk behaviors. Furthermore, all participants (100%) agreed that such stories can promote early detection of HNC, primarily through social media, followed by the internet, and television. Conclusions: The study identified notable individuals and gathered positive perspectives from professionals. Our results suggest that notable people could serve as potential advocates for HNC prevention. Further research is warranted to explore the potential of this prevention strategy.

Cancer Stem Cells in Oral Squamous Cell Carcinoma: A Narrative Review on Experimental Characteristics and Methodological Challenges

Cancer stem cells (CSCs) represent a subpopulation of cancer cells that are believed to initiate and drive cancer progression. In animal models, xenotransplanted CSCs have demonstrated the ability to produce tumors. Since their initial isolation in blood cancers, CSCs have been identified in various solid human cancers, including oral squamous cell carcinoma (OSCC). In addition to their tumorigenic properties, dysregulated stem-cell-related signaling pathways-Wnt family member (Wnt), neurogenic locus notch homolog protein (Notch), and hedgehog-have been shown to endow CSCs with characteristics like self-renewal, phenotypic plasticity, and chemoresistance, contributing to recurrence and treatment failure. Consequently, CSCs have become targets for new therapeutic agents, with some currently in different phases of clinical trials. Notably, small molecule inhibitors of the hedgehog signaling pathway, such as vismodegib and glasdegib, have been approved for the treatment of basal cell carcinoma and acute myeloid leukemia, respectively. Other strategies for eradicating CSCs include natural compounds, nano-drug delivery systems, targeting mitochondria and the CSC microenvironment, autophagy, hyperthermia, and immunotherapy. Despite the extensive documentation of CSCs in OSCC since its first demonstration in head and neck (HN) SCC in 2007, none of these novel pharmacological approaches have yet entered clinical trials for OSCC patients. This narrative review summarizes the in vivo and in vitro evidence of CSCs and CSC-related signaling pathways in OSCC, highlighting their role in promoting chemoresistance and immunotherapy resistance. Additionally, it addresses methodological challenges and discusses future research directions to improve experimental systems and advance CSC studies.

Trends and socioeconomic inequalities in the dental attendance of adult smokers in Scotland from 2009 to 2019, a repeated cross-sectional study

BACKGROUND

Smoking continues to be the single largest cause of preventable disease and death and a major contributor to health inequalities. Dental professionals are well placed to offer behavioural support in combination with pharmacotherapy to increase smoking cessation rates across the population. We aimed to assess the trends and socioeconomic inequalities in the dental attendance of adult smokers in Scotland from 2009 to 2019 and examine the potential population reach of dental settings for smoking cessation interventions.

METHODS

A secondary analysis was conducted of combined Scottish Health Surveys (SHeS) from 2009/11, 2013/15 and 2017/19. 'Recent' dental attendance (within the past two years) was the focus and descriptive analysis examined attendance of self-reported smokers compared to non-smokers and stratified by the area-based Scottish Index of Multiple Deprivation (SIMD) and individual socioeconomic measures (income, education, and occupation). Generalised linear models were used to model recent attendance in non-smokers relative to smokers adjusted by the socioeconomic measures, for each of the survey cohorts separately. Absolute differences and risk ratios were calculated with 95% Confidence Intervals (CI).

RESULTS

Recent dental attendance was generally high and increased in both smokers (70-76%) and non-smokers (84-87%) from 2009/11 to 2017/19 and increased across all SIMD groups. After adjustment for sociodemographic variables, the adjusted Risk Difference (aRD) for recent attendance between non-smokers and smokers was 8.9% (95% CI 4.6%, 13.2%) by 2017/19. Within smokers, recent attendance was 7-9% lower in those living in the most deprived areas compared to those living in the least deprived areas over the three surveys.

CONCLUSIONS

SHeS data from 2009 to 2019 demonstrated that a high and increasing proportion of smokers in the population attend the dentist, albeit slightly less frequently than non-smokers. There were large inequalities in the dental attendance of smokers, to a lesser extent in non-smokers, and these persisted over time. Dental settings provide a good potential opportunity to deliver population-level smoking cessation interventions, but smokers in the most deprived groups and older age groups may be harder to reach. Consideration should be given to ensure that these groups are given appropriate proportionate support to take up preventive interventions.

An oral cancer screening program in Brazil: Analysis of seven years of outcome after its implementation in the suburban cities of São Paulo

OBJECTIVE

To describe the implementation of an oral cancer screening program at the Barretos Cancer Hospital (BCH) and present the outcome based on data obtained from 2014 to 2020.

MATERIALS AND METHODS

The residents of the Regional Health District of Barretos (DRS-V) were personally invited by community health agents or nurses, and among 13,973 people, 15,222 oral examinations were carried out over the years in 18 of its municipalities. Oral examinations were performed at the Mobile Dental Unit and at the Prevention Department of the BCH. Inclusion criteria were being 35 years of age or older, having a personal history of tobacco or alcohol consumption, or having a lesion in the oral cavity found by community health agent or self-reported, regardless of age or risk factors.

RESULTS AND CONCLUSION

The main result of our study was the stages of oral cancer among screen detected cases were smaller compared to cases in the hospital registry, in the state and in Brazil. Oral cancer detection rate per 1,000 oral examinations was 10.7.The early stages of oral cancer found by screening in primary care facilities or using mobile units suggest that, when organized, screening may improve the prognosis of oral cancer.

Oral squamous cell carcinomas and oral potentially malignant disorders: A Latin American study

OBJECTIVE

To determine the frequency of oral squamous cell carcinoma (OSCC) associated or not with oral potentially malignant disorders (OPMD), and the epidemiological profile and traditional risk factors in Latin America.

METHODS

A retrospective observational study was conducted in 17 Latin American centres. There were included cases of OSCC, analysing age, gender, OSCC and their association with previous OPMD. Clinicopathological variables were retrieved. The condition of sequential-OSCC versus OSCC-de novo (OSCC-dn) was analysed concerning the aforementioned variables. Quantitative variables were analysed using Student's t-test, and qualitative variables with chi-square.

RESULTS

In total, 2705 OSCC were included with a mean age of 62.8 years old. 55.8% were men. 53.75% of the patients were smokers and 38% were common drinkers. The lateral tongue border was the most affected site (24.65%). There were regional variations in OPMD, being leukoplakia the most frequent. Of the overall 2705 OSCC cases, 81.4% corresponded to OSCC-dn, while s-OSCC were 18.6%. Regarding lip vermillion SCC, 35.7% corresponded to de novo lip SCC and 64.3% were associated with previous OPMD.

CONCLUSIONS

In Latin America, OSCC-dn seems to be more frequent with regional variations of some clinical and histopathological features. Further prospective studies are needed to analyse this phenomenon.

The association between referral by specialists in oral diagnosis on survival rates of patients with oral cancer: A retrospective cohort study

BACKGROUND

To assess the influence of diagnosis and referral provided by specialists in oral diagnosis on disease-free survival and overall survival of patients with oral cancer.

METHODS

A cohort of 282 patients with oral cancer treated at a regional cancer hospital from 1998 to 2016 was analyzed retrospectively. The referral register of the patients was analyzed and assigned to two groups: (1) those referred by oral diagnosis specialists (n = 129), or (2) those referred by nonspecialized professionals (n = 153). The cancer treatment evolution was assessed from the patients' records, and the outcome was registered concerning cancer recurrence and death. Sociodemographic and clinicopathological variables were explored as predictors of disease-free survival and overall survival.

RESULTS

Group 1 exhibited lower T stages and a reduced incidence of regional and distant metastases. Surgery was performed in 75.2% of cases in Group 1, while in Group 2, the rate was 60.8%. Advanced T stages and regional metastases reduced the feasibility of surgery. Higher TNM stages and tumor recurrence were associated with decreased disease-free survival, while surgical intervention was a protective factor. Higher TNM stage had a negative impact on the overall survival.

CONCLUSION

Specialized oral diagnosis did not directly impact disease-free survival and overall survival and did not influence the indication of surgery in oral cancer; however, it was associated with the diagnosis of early tumors and better prognosis.

Targeting compensatory proliferation signals in oral cancer

Apoptosis is an orchestrated phenomenon that regulates cell populations in physiological and pathological conditions. Carcinogenesis involves a state of disequilibrium between cell proliferation and cell death. The resistance to conventional therapeutic modalities of cancer, including surgery, radiotherapy, and chemotherapy, can be explained by the compensatory repair and regeneration that occurs in the tumor microenvironment following apoptosis through the apoptotic compensatory proliferation signaling microvesicles (ACPSVs) or apoptotic extracellular microvesicles (ApoEVs). These microvesicles provide proliferative signals and act as mutagens, triggering cell proliferation, angiogenesis, immune evasion, metastasis, and invasion. This review discusses the phenomenon of apoptosis-induced proliferation and the role of ApoEVs in establishing an oncoregenerative niche, resulting in therapeutic resistance and recurrence of malignancies.

Salivary Histamine Levels in Patients with Oral Lichen Planus Lesions

Background and Objectives: An oral lichen planus (OLP) chronic lesion refers to a group of oral potentially malignant disorders (OPMDs) that still lack a proper understanding from the point of view of relevant biomarkers for diagnostics and prognosis. The aim of the study was to assess the salivary histamine levels in patients with oral lichen planus lesions. Materials and Methods: The study included a group of 76 patients with oral lichen planus. General diseases and medication taken, smoking habits, severity of pain assessed using a visual analogue scale (VAS), oral hygiene status, and duration of OLP were evaluated. ELISA diagnostics for histamines in saliva levels were assessed. Results: The histamine levels in the OLP group were higher (0.468) in comparison with the control group (0.056), without a statistically significant value p = 0.090 (Mann-Whitney U Test). The median age of 76 OLP patients was 63 years (min 22.0-max. 81), with the biological sex being 80.3% females and 15 19.7% males. The average duration of OLP lesion presence was 29.4 months (SD 37.1) and the median value was 14.5 months. The median of the VAS was 3.0. OLP assessment in accordance with the Malhotra methodology showed the highest frequency-30.3% for only two of the point areas involved and 17.1% for three points. Clinical assessment of the different OLP grades, severity, and oral site involvement and the VAS in correlation with histamine salivary levels showed a lack of statistical significance in the investigated population. Conclusions: Undertaking further research could provide further possibilities for searching for general factors in OLP development.

Oral cancer diagnosis communication: Impact of an educational intervention using the SPIKES protocol

OBJECTIVE

This study evaluated the influence of a single educational intervention on the perception and knowledge of strategies for communicating oral cancer diagnoses.

METHODS

A educational intervention, 72 dentists and 41 dental undergraduates participated in the 'Maio Vermelho Project', a continuing education activity. Participants completed a 14-question online questionnaire concerning their experiences and perceptions of delivering difficult news. The educational intervention featured an interview illustrating the SPIKES protocol, broadcast on YouTube.

RESULTS

Participants had a mean age of 40 years. A minority (21.2%) had encountered or experienced communicating an oral cancer diagnosis. Exposure to lectures on this topic during their education was uncommon (22.1%) but more prevalent among students. After the intervention, confidence in communicating a cancer diagnosis (29.2%) and addressing the patient's family (30.1%) in line with the SPIKES protocol increased.

CONCLUSION

A training deficit persists in delivering cancer diagnoses, highlighting the need for educational interventions to empower students and professionals in this critical procedure. Integration of this topic into the dental undergraduate curriculum is imperative.

CLINICAL RELEVANCE

Effectively communicating a cancer diagnosis poses challenges to healthcare professionals, impacting treatment outcomes. Implementing educational interventions ensures that professionals are well prepared to navigate this complex task, ultimately improving patient care.

Cancer Trials Ecosystem in India-Ready for Prime Time?

Executing global clinical trials for cancer is a long, expensive, and complex undertaking. While selecting countries global studies, sponsors must consider several aspects including patient pool, quality of trained investigators, competing trials, availability of infrastructure, and financial investment versus returns. With a large, often treatment-naïve, and diverse patient pool, relatively low cost, good quality health care facilities in urban areas, and a robust and well-trained workforce, India offers several advantages for conducting oncology clinical trials. However, there remains challenges, including a shifting regulatory environment in recent decades. With the implementation of the New Drugs and Clinical Trial Rules in 2019, India's regulatory atmosphere seems to have stabilized. In this article, we present a review of the evolving clinical trial landscape in India, highlight the current regulatory scenario, and discuss the advantages and challenges of selecting India as a potential location for conducting global oncology clinical trials.

Differences among oral carcinomas arising de novo from those associated with oral potentially malignant disorders: a systematic review and meta-analysis

OBJECTIVE

To analyze the frequency of sequential oral squamous cell carcinomas (s-OSCC), preceded by oral potentially malignant disorders, and OSCC de novo (OSCC-dn) and explore differences in their clinicopathologic presentations.

STUDY DESIGN

A structured electronic search strategy identified studies that analyzed frequency, clinical, biological, demographic, biomarkers, and prognostic features of s-OSCC and OSCC-dn according to PRISMA guidelines in PubMed, Scopus, Cochrane Library, and Google Scholar, up to January 31, 2023. Inclusion criteria were original English, Spanish, Portuguese, French, Italian, and German cross-sectional, cohort, and case-control studies. The quality of studies was assessed using the Agency for Research and Health Quality tool and the Newcastle-Ottawa Scale tool.

RESULTS

The final selection included 40 studies. OSCC-dn and s-OSCC represent, respectively, 71% and 29% of cases of OSCC (P = .00), showing a higher percentage of T1 or of T1+T2 in s-OSCC (P < .0001). The association meta-analysis showed OSCC-dn with a significant association. The meta-analysis showed that s-OSCC was significantly associated with smaller tumor size, absence of distant metastases, relapses, male sex, and tumor sites different from tongue; and OSCC-dn was associated with more advanced tumor size, more regional and distant metastases, more advanced stages, and worse survival.

CONCLUSIONS

S-OSCC was less frequent than expected. OSCC-dn seems to have specific clinical, biological, and prognostic features. Future perspectives on oral cancer prevention should address novel approaches and alternatives to screening, such as urgent referral of OSCC-dn.

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.

Change and pathological significance of glycogen content in oral squamous cell carcinoma and oral submucous fibrosis

OBJECTIVE

This study aimed to investigate the change and pathological significance of glycogen content in oral squamous cell carcinoma (OSCC) and oral submucous fibrosis (OSF).

METHODS AND MATERIALS

13 normal oral mucosa (NOM), 12 OSF mucosa, and 35 pairs of OSCC tissues and their corresponding adjacent mucosa tissues (AT) were collected from Xiangya Hospital for PAS staining to detect glycogen. Transcriptome sequencing data from OSCC were used to compare glycogen metabolism gene expression differences. Kaplan-Meier method was conducted to estimate Recurrence-free survival (RFS).

RESULTS

Glycogen levels were lower in OSF than in NOM and lower in OSCC than in AT. Transcriptome sequencing data analysis showed the expression of most glycogenolysis genes was increased and the expression of glycogen synthesis genes including PPP1R3C and GBE1 was decreased in OSCC tissues. High glycogen level was correlated with poor prognosis in OSCC patients under the background of OSF.

CONCLUSION

Glycogen may be used as a potential diagnostic biomolecule for OSF and OSCC, as well as a potential prognostic factor for OSCC in the context of OSF.

Latin American Consensus on the Treatment of Head and Neck Cancer

Head and neck squamous cell carcinoma (HNSCC) is well known as a serious health problem worldwide, especially in low-income countries or those with limited resources, such as most countries in Latin America. International guidelines cannot always be applied to a population from a large region with specific conditions. This study established a Latin American guideline for care of patients with head and neck cancer and presented evidence of HNSCC management considering availability and oncologic benefit. A panel composed of 41 head and neck cancer experts systematically worked according to a modified Delphi process on (1) document compilation of evidence-based answers to different questions contextualized by resource availability and oncologic benefit regarding Latin America (region of limited resources and/or without access to all necessary health care system infrastructure), (2) revision of the answers and the classification of levels of evidence and degrees of recommendations of all recommendations, (3) validation of the consensus through two rounds of online surveys, and (4) manuscript composition. The consensus consists of 12 sections: Head and neck cancer staging, Histopathologic evaluation of head and neck cancer, Head and neck surgery-oral cavity, Clinical oncology-oral cavity, Head and neck surgery-oropharynx, Clinical oncology-oropharynx, Head and neck surgery-larynx, Head and neck surgery-larynx/hypopharynx, Clinical oncology-larynx/hypopharynx, Clinical oncology-recurrent and metastatic head and neck cancer, Head and neck surgery-reconstruction and rehabilitation, and Radiation therapy. The present consensus established 48 recommendations on HNSCC patient care considering the availability of resources and focusing on oncologic benefit. These recommendations could also be used to formulate strategies in other regions like Latin America countries.

Reported physical examination methods for screening of oral cancer and oral potentially malignant disorders: a systematic review

OBJECTIVE

This systematic review aimed to describe the method followed during physical examination and the anatomical structures of the head and neck assessed in screening for oral cancer and oral potentially malignant disorders (OPMDs).

STUDY DESIGN

An extensive literature search was carried out using MEDLINE/PubMed, EMBASE, Scopus, LILACS, Web of Science, Cochrane databases, and gray literature. The risk of bias was available in all papers included.

RESULTS

Of 9,688 records identified, 27 were included in this review, reporting data from 356,250 individuals screened and distributed across 11 countries. Most of these (n = 19) were based on 1 round of screening conducted by a dental professional or other health care workers. Most screening programs included visual inspection and palpation of the lips, oral cavity, and the most visible oropharyngeal sites, but the descriptions reported were imprecise. Additional inspection and palpation of the neck (submental, submandibular, cervical, and supraclavicular regions) to assess for the presence of swellings and any palpable neck nodes were also performed in 15 programs.

CONCLUSION

In conclusion, there was considerable heterogeneity in the method of physical examination in screening programs for oral cancer and OPMDs among the included studies.

Factors influencing delayed referral of oral cancer patients from family dentists to the core hospital

Background/purpose

Most oral cancer (OC) cases are identified by family dentists in Japan. However, a significant number of patients with OC in Japan are referred to core hospitals at advanced stages. Therefore, identifying the factors that contribute to delayed referrals from family dentists to core hospitals is crucial for detecting OC in its earlier stages. The aim of this retrospective study was to identify the risk factors for referral delays from family dentists to core hospitals.

Materials and methods

The study included 63 patients with OC who were referred by family dentists to the Yamagata University Hospital between 2010 and 2022. The clinical parameters related to referral delays were retrospectively investigated using letters of reference provided by the family dentists and patient charts. Backward multiple regression analysis was performed to identify the relationships between the length of referral delay and potential risk factors. Additionally, backward multivariate logistic regression analysis was performed to examine the independent association between referral delays of >4 weeks and several clinical parameters.

Results

Multiple regression analysis revealed that misdiagnosis of malignant lesions by family dentists (P = 0.047) was significantly associated with longer referral delays. Additionally, misdiagnosis of malignant lesions by family dentists was also an independent risk factor for referral delays of >4 weeks (odds ratio, 10.387; P = 0.006).

Conclusion

Misdiagnosis of malignant lesions by family dentists was a significant risk factor for referral delays from family dentists to core hospitals. Our results will motivate family dentists to improve their ability to diagnose OC.

Near-infrared-II Ag2S quantum dot probes targeting podoplanin enhance immunotherapy in oral squamous cell carcinoma

Partial epithelial-mesenchymal transition (pEMT) plays a vital role in oral squamous cell carcinoma (OSCC) cervical lymph node metastasis and tumor immune escape as an immune barrier. However, targeted interventions for pEMT have yet to be established. In this study, we generated an αPDPN-Ag2S probe by modifying a Podoplanin(PDPN) monoclonal antibody on the surface of near infrared (NIR)-II Ag2S quantum dots (QDs) with carboxyl groups through an amide reaction. Then, we evaluated its in vivo targeting ability, therapeutic efficacy of eliminating pEMT using αPDPN-Ag2S-mediated NIR-II photoimmunotherapy (PIT) and biological safety. Here, we found that pEMT is related to CD8 + T-cell infiltration in our human OSCC tissue microarray. Compared with PdpnWT SCC7, the slower growth rate of subcutaneous graft tumors implanted with PdpnKD SCC7 was associated with a change in the tumor immune microenvironment (TIM) in an immunocompetent C3H/HeJ mouse model. In vitro, αPDPN-Ag2S plus NIR 808 nm laser irradiation induced SCC7 cell death. In vivo, NIR-II imaging results show that the αPDPN-Ag2S probe has a good active-targeting ability in a 4-nitroquinoline 1-oxide (4NQO)-induced C57 mouse OSCC model and C3H/HeJ SCC7 subcutaneous graft tumor model. Elimination of pEMT cells by NIR-II αPDPN-Ag2S probe-mediated PIT significantly reversed the local immunosuppressive tumor microenvironment and enhanced PD-1 immunotherapy efficacy. The safety profiles of αPDPN-Ag2S in BALB/c mice were also acceptable. Thus, αPDPN-Ag2S has important clinical translational value in predicting the risk of cervical lymph node metastasis. Importantly, our study proposed a new way to improve the efficacy of tumor immunotherapy.

Forecasting Head and Neck Cancer Trends in GCC Countries: Implications for Public Health Policy and Strategy

Purpose

The data available on the incidence and mortality rates of head and neck cancer types (HNCs) in the Gulf Cooperation Council countries (GCC) have relied on global trends and covered only certain cancer sites, types or certain age groups. This study aimed to assess the incidence and mortality rates of head and neck cancer (HNCs) within the Gulf Cooperation Council (GCC) countries, providing insights into their geographic variability in 2020.

Methods

Prediction of the magnitude of the disease to 2040 was explored based on demographic projections. Estimates of incidence and mortality and the population projections were extracted from the Global Cancer Observatory (GLOBOCAN) database and the United Nations Department of Economic and Social Affairs respectively for the time frame 2020 to 2040. Additionally, we analyzed the distribution of cases and deaths by age and sex for both time periods.

Results

The analysis indicates varying patterns in HNC rates across GCC countries in 2020, with Oman and Saudi Arabia carrying the highest burden. Projections for 2040 reveal a substantial increase in new HNC cases and related deaths, particularly in Qatar, UAE, and Bahrain. Furthermore, incidence rates are predicted to rise significantly for individuals aged 50 and older, while remaining relatively stable for those under 50. With regards to sex, males generally exhibit higher rates, except in Qatar.

Conclusion

HNC burden is anticipated to rise significantly in the GCC, with variations per age, sex and geographical location. By 2040, a 2-3-fold increase in HNCs in the GCC is anticipated, emphasizing the need for focused public health strategies to address this rising health challenge.

Potential of melatonin to reverse epigenetic aberrations in oral cancer: new findings

It is now an accepted principle that epigenetic alterations cause cellular dyshomeostasis and functional changes, both of which are essential for the initiation and completion of the tumor cycle. Oral carcinogenesis is no exception in this regard, as most of the tumors in the different subsites of the oral cavity arise from the cross-reaction between (epi)genetic inheritance and the huge challenge of environmental stressors. Currently, the biochemical machinery is put at the service of the tumor program, halting the cell cycle, triggering uncontrolled proliferation, driving angiogenesis and resistance to apoptosis, until the archetypes of the tumor phenotype are reached. Melatonin has the ability to dynamically affect the epigenetic code. It has become accepted that melatonin can reverse (epi)genetic aberrations present in oral and other cancers, suggesting the possibility of enhancing the oncostatic capacity of standard multimodal treatments by incorporating this indolamine as an adjuvant. First steps in this direction confirm the potential of melatonin as a countermeasure to mitigate the detrimental side effects of conventional first-line radiochemotherapy. This single effect could produce synergies of extraordinary clinical importance, allowing doses to be increased and treatments not to be interrupted, ultimately improving patients' quality of life and prognosis. Motivated by the urgency of improving the medical management of oral cancer, many authors advocate moving from in vitro and preclinical research, where the bulk of melatonin cancer research is concentrated, to systematic randomized clinical trials on large cohorts. Recognizing the challenge to improve the clinical management of cancer, our motivation is to encourage comprehensive and robust research to reveal the clinical potential of melatonin in oral cancer control. To improve the outcome and quality of life of patients with oral cancer, here we provide the latest evidence of the oncolytic activity that melatonin can achieve by manipulating epigenetic patterns in oronasopharyngeal tissue.

Oral cancer in pregnancy: A systematic review

PURPOSE

Oral cancers in pregnancy (OCiP) are rare, however when diagnosed it complicates both the treatment of cancer and the outcome of pregnancy. The aim of this systematic review was to assess the factors impacting the foetal and maternal outcome in OCiP.

MATERIALS AND METHODS

A systematic search was performed on the following electronic databases: PubMed, Scopus, ScienceDirect and Google Scholar. Only histopathologically diagnosed cases of oral cancer in pregnant patients were included. The Joanna Briggs Institute questionnaire for case reports was used to assess the risk of bias. Logistic regression analysis was used to assess the factors impacting foetal and maternal outcome.

RESULTS

Out of the 40 cases reported, 28 were squamous cell carcinomas and 7 osteosarcomas. Logistic regression analysis demonstrated a non-significant association between age of patient, staging, trimester and treatment to maternal and foetal outcome. The overall recurrence, maternal death and foetal death for OCiP was 25 %, 30.77 % and 3.45 % respectively.

CONCLUSION

It could be concluded with low evidence level that none of the factors explored in this SR affected the maternal and foetal outcome. A regular oral check-up, particularly the tongue of pregnant females is recommended to identify any early signs of inflammation or oral cancer and subjected to biopsy to identify malignancy or dysplasia.

A paradigm shift in the prevention and diagnosis of oral squamous cell carcinoma

BACKGROUND

Oral squamous cell carcinoma (OSCC) is a widespread disease with only 50%-60% 5-year survival. Individuals with potentially malignant precursor lesions are at high risk.

METHODS

Survival could be increased by effective, affordable, and simple screening methods, along with a shift from incisional tissue biopsies to non-invasive brush biopsies for cytology diagnosis, which are easy to perform in primary care. Along with the explainable, fast, and objective artificial intelligence characterisation of cells through deep learning, an easy-to-use, rapid, and cost-effective methodology for finding high-risk lesions is achievable. The collection of cytology samples offers the further opportunity of explorative genomic analysis.

RESULTS

Our prospective multicentre study of patients with leukoplakia yields a vast number of oral keratinocytes. In addition to cytopathological analysis, whole-slide imaging and the training of deep neural networks, samples are analysed according to a single-cell RNA sequencing protocol, enabling mapping of the entire keratinocyte transcriptome. Mapping the changes in the genetic profile, based on mRNA expression, facilitates the identification of biomarkers that predict cancer transformation.

CONCLUSION

This position paper highlights non-invasive methods for identifying patients with oral mucosal lesions at risk of malignant transformation. Reliable non-invasive methods for screening at-risk individuals bring the early diagnosis of OSCC within reach. The use of biomarkers to decide on a targeted therapy is most likely to improve the outcome. With the large-scale collection of samples following patients over time, combined with genomic analysis and modern machine-learning-based approaches for finding patterns in data, this path holds great promise.

Non-coding RNAs/DNMT3B axis in human cancers: from pathogenesis to clinical significance

Cancer is a complex disease with many contributing factors, and researchers have gained extensive knowledge that has helped them understand the diverse and varied nature of cancer. The altered patterns of DNA methylation found in numerous types of cancer imply that they may play a part in the disease's progression. The human cancer condition involves dysregulation of the DNA methyltransferase 3 beta (DNMT3B) gene, a prominent de novo DNA methyltransferase, and its abnormal behavior serves as an indicator for tumor prognosis and staging. The expression of non-coding RNAs (ncRNAs), which include microRNAs (miRNA), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), is critical in controlling targeted gene expression and protein translation and their dysregulation correlates with the onset of tumors. NcRNAs dysregulation of is a critical factor that influences the modulation of several cellular characteristics in cancerous cells. These characteristics include but are not limited to, drug responsiveness, angiogenesis, metastasis, apoptosis, proliferation, and properties of tumor stem cell. The reciprocal regulation of ncRNAs and DNMT3B can act in synergy to influence the destiny of tumor cells. Thus, a critical avenue for advancing cancer prevention and treatment is an inquiry into the interplay between DNMT3B and ncRNAs. In this review, we present a comprehensive overview of the ncRNAs/DNMT3B axis in cancer pathogenesis. This brings about valuable insights into the intricate mechanisms of tumorigenesis and provides a foundation for developing effective therapeutic interventions.

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.

Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment

BACKGROUND

Surgery is a common treatment option in oral cavity cancer (and less frequently in oropharyngeal cancer) to remove the primary tumour and sometimes neck lymph nodes. People with early-stage disease may undergo surgery alone or surgery plus radiotherapy, chemotherapy, immunotherapy/biotherapy, or a combination of these. Timing and extent of surgery varies. This is the third update of a review originally published in 2007.

OBJECTIVES

To evaluate the relative benefits and harms of different surgical treatment modalities for oral cavity and oropharyngeal cancers.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was 9 February 2022.

SELECTION CRITERIA

Randomised controlled trials (RCTs) that compared two or more surgical treatment modalities, or surgery versus other treatment modalities, for primary tumours of the oral cavity or oropharynx.

DATA COLLECTION AND ANALYSIS

Our primary outcomes were overall survival, disease-free survival, locoregional recurrence, and recurrence; and our secondary outcomes were adverse effects of treatment, quality of life, direct and indirect costs to patients and health services, and participant satisfaction. We used standard Cochrane methods. We reported survival data as hazard ratios (HRs). For overall survival, we reported the HR of mortality, and for disease-free survival, we reported the combined HR of new disease, progression, and mortality; therefore, HRs below 1 indicated improvement in these outcomes. We used GRADE to assess certainty of evidence for each outcome.

MAIN RESULTS

We identified four new trials, bringing the total number of included trials to 15 (2820 participants randomised, 2583 participants analysed). For objective outcomes, we assessed four trials at high risk of bias, three at low risk, and eight at unclear risk. The trials evaluated nine comparisons; none compared different surgical approaches for excision of the primary tumour. Five trials evaluated elective neck dissection (ND) versus therapeutic (delayed) ND in people with oral cavity cancer and clinically negative neck nodes. Elective ND compared with therapeutic ND probably improves overall survival (HR 0.64, 95% confidence interval (CI) 0.50 to 0.83; I2 = 0%; 4 trials, 883 participants; moderate certainty) and disease-free survival (HR 0.56, 95% CI 0.45 to 0.70; I2 = 12%; 5 trials, 954 participants; moderate certainty), and probably reduces locoregional recurrence (HR 0.58, 95% CI 0.43 to 0.78; I2 = 0%; 4 trials, 458 participants; moderate certainty) and recurrence (RR 0.58, 95% CI 0.48 to 0.70; I2 = 0%; 3 trials, 633 participants; moderate certainty). Elective ND is probably associated with more adverse events (risk ratio (RR) 1.31, 95% CI 1.11 to 1.54; I2 = 0%; 2 trials, 746 participants; moderate certainty). Two trials evaluated elective radical ND versus elective selective ND in people with oral cavity cancer, but we were unable to pool the data as the trials used different surgical procedures. Neither study found evidence of a difference in overall survival (pooled measure not estimable; very low certainty). We are unsure if there is a difference in effect on disease-free survival (HR 0.57, 95% CI 0.29 to 1.11; 1 trial, 104 participants; very low certainty) or recurrence (RR 1.21, 95% CI 0.63 to 2.33; 1 trial, 143 participants; very low certainty). There may be no difference between the interventions in terms of adverse events (1 trial, 148 participants; low certainty). Two trials evaluated superselective ND versus selective ND, but we were unable to use the data. One trial evaluated supraomohyoid ND versus modified radical ND in 332 participants. We were unable to use any of the primary outcome data. The evidence on adverse events was very uncertain, with more complications, pain, and poorer shoulder function in the modified radical ND group. One trial evaluated sentinel node biopsy versus elective ND in 279 participants. There may be little or no difference between the interventions in overall survival (HR 1.00, 95% CI 0.90 to 1.11; low certainty), disease-free survival (HR 0.98, 95% CI 0.90 to 1.07; low certainty), or locoregional recurrence (HR 1.04, 95% CI 0.91 to 1.19; low certainty). The trial provided no usable data for recurrence, and reported no adverse events (very low certainty). One trial evaluated positron emission tomography-computed tomography (PET-CT) following chemoradiotherapy (with ND only if no or incomplete response) versus planned ND (before or after chemoradiotherapy) in 564 participants. There is probably no difference between the interventions in overall survival (HR 0.92, 95% CI 0.65 to 1.31; moderate certainty) or locoregional recurrence (HR 1.00, 95% CI 0.94 to 1.06; moderate certainty). One trial evaluated surgery plus radiotherapy versus radiotherapy alone and provided very low-certainty evidence of better overall survival in the surgery plus radiotherapy group (HR 0.24, 95% CI 0.10 to 0.59; 35 participants). The data were unreliable because the trial stopped early and had multiple protocol violations. In terms of adverse events, subcutaneous fibrosis was more frequent in the surgery plus radiotherapy group, but there were no differences in other adverse events (very low certainty). One trial evaluated surgery versus radiotherapy alone for oropharyngeal cancer in 68 participants. There may be little or no difference between the interventions for overall survival (HR 0.83, 95% CI 0.09 to 7.46; low certainty) or disease-free survival (HR 1.07, 95% CI 0.27 to 4.22; low certainty). For adverse events, there were too many outcomes to draw reliable conclusions. One trial evaluated surgery plus adjuvant radiotherapy versus chemotherapy. We were unable to use the data for any of the outcomes reported (very low certainty).

AUTHORS' CONCLUSIONS

We found moderate-certainty evidence based on five trials that elective neck dissection of clinically negative neck nodes at the time of removal of the primary oral cavity tumour is superior to therapeutic neck dissection, with increased survival and disease-free survival, and reduced locoregional recurrence. There was moderate-certainty evidence from one trial of no difference between positron emission tomography (PET-CT) following chemoradiotherapy versus planned neck dissection in terms of overall survival or locoregional recurrence. The evidence for each of the other seven comparisons came from only one or two studies and was assessed as low or very low-certainty.

Oral cancer knowledge, attitudes, and practices among senior dental students in Yemen: a multi-institution study

BACKGROUND

The "Knowledge, attitude, and practice (KAP)" approach is crucial in health system. Appreciating the current KAP status will reveal the extent of the efficiency of applied health strategies, and subsequently help to determine the appropriate health policy to be employed for improving the health indicators of a given disease/condition, including Oral Cancer (OC). This large-scale cross-sectional study aimed to assess knowledge, attitude, and practice on OC among senior dental students in Yemen.

METHODS

A pre-validated online questionnaire was used for data collection. It consisted of a series of close-ended questions on knowledge, attitudes and practices related to OC. Yemeni dental students in clinical levels (4th and 5th years) from nine dental schools based in four major cities were invited to complete the survey. The SPSS Version 28.0 was used for data analysis. Differences by different grouping factors were assessed by Chi-squared and Mann Whitney-U tests, as appropriate.

RESULTS

A total of 927 students completed the questionnaire: a response rate of 43%. While the majority identified smoking (93.8%), and smokeless tobacco (92.1%) as potential risk factors of OC, only 76.2% recognized sun exposure as a risk factor for lip cancer and only 50% were aware of old age as a risk factor of OC. Regarding clinical signs of OC, 84.1% reported that OC can present as non-healing ulcer, but only two thirds of the participants recognized that OC can present as a white and/or red lesion. With respect to practices, although 92.1% reported asking their patients regarding oral habits, only 78% reported they regularly carry out a soft tissue examination. Only 54.5% of the participants considered themselves to be well-trained to provide smoking cessation advice, and 21% were confident regarding their knowledge on OC. The 5th year students showed significantly better knowledge and practices than the 4th year students did (p < 0.01).

CONCLUSION

The study suggests significant gaps in knowledge, attitudes, and practices of senior dental students in Yemen regarding OC. The findings also underscore the urgent need to improve OC teaching and training of undergraduate dental students, and to provide periodic well-structured continuing professional development activities for dental professionals.

The Way to Malignant Transformation: Can Epigenetic Alterations Be Used to Diagnose Early-Stage Head and Neck Cancer?

Identifying and treating tumors early is the key to secondary prevention in cancer control. At present, prevention of oral cancer is still challenging because the molecular drivers responsible for malignant transformation of the 11 clinically defined oral potentially malignant disorders are still unknown. In this review, we focused on studies that elucidate the epigenetic alterations demarcating malignant and nonmalignant epigenomes and prioritized findings from clinical samples. Head and neck included, the genomes of many cancer types are largely hypomethylated and accompanied by focal hypermethylation on certain specific regions. We revisited prior studies that demonstrated that sufficient uptake of folate, the primary dietary methyl donor, is associated with oral cancer reduction. As epigenetically driven phenotypic plasticity, a newly recognized hallmark of cancer, has been linked to tumor initiation, cell fate determination, and drug resistance, we discussed prior findings that might be associated with this hallmark, including gene clusters (11q13.3, 19q13.43, 20q11.2, 22q11-13) with great potential for oral cancer biomarkers, and successful examples in screening early-stage nasopharyngeal carcinoma. Although one-size-fits-all approaches have been shown to be ineffective in most cancer therapies, the rapid development of epigenome sequencing methods raises the possibility that this nonmutagenic approach may be an exception. Only time will tell.

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.