Association of Smokeless Tobacco Use and Oral Cancer: A Systematic Global Review and Meta-Analysis

5. Facilitating Positive Health Behaviors and Well-being to Improve Health Outcomes: Standards of Care in Diabetes-2025

The American Diabetes Association (ADA) "Standards of Care in Diabetes" includes the ADA's current clinical practice recommendations and is intended to provide the components of diabetes care, general treatment goals and guidelines, and tools to evaluate quality of care. Members of the ADA Professional Practice Committee, an interprofessional expert committee, are responsible for updating the Standards of Care annually, or more frequently as warranted. For a detailed description of ADA standards, statements, and reports, as well as the evidence-grading system for ADA's clinical practice recommendations and a full list of Professional Practice Committee members, please refer to Introduction and Methodology. Readers who wish to comment on the Standards of Care are invited to do so at professional.diabetes.org/SOC.

Oral Cancer Incidence Among Adult Males With Current or Former Use of Cigarettes or Smokeless Tobacco: Population-Based Study

Background

Tobacco use has been identified as a risk factor for oral cancer worldwide. However, relative oral cancer incidence among adults who smoke cigarettes, use smokeless tobacco products (ST), have transitioned from cigarettes to ST, quit cigarettes and/or ST ("quitters"), or never used tobacco has not been well studied.

Objective

We aim to present population-based oral cancer incidence rates for adults who smoke cigarettes, use ST, are former smokers who now use ST, or quit.

Methods

We estimated cross-sectional incidence rates and incidence rate ratios (IRRs) using data from statewide cancer registries (Colorado, Florida, North Carolina, and Texas) and population counts derived from national surveys using combined data from 2014-2017. A random-effect meta-analysis approach was used to summarize estimates among these groups, based on multiple imputation-based IRR estimates by state and age group while considering potential heterogeneity.

Results

A total of 19,536 oral cancer cases were identified among adult males 35 years and older in the study geographies and period. The oral cancer incidence rate among adults who smoke was significantly higher than the ST group (2.6 times higher, 95% CI 2.0-3.3, P<.001), 3.6 (95% CI 3.2-4.1, P<.001) times higher than the never users, and 2.4 (95% CI 1.8-3.1, P<.001) times higher compared to former smokers who now use ST. The IRR among the ST group relative to never users was 1.4 (95% CI 1.1-1.9, P=.02). The IRR between former smokers who now use ST and those who quit was 1.4 (95% CI 1.0-2.1, P=.08).

Conclusions

Findings from this population-based study with a large number of oral cancer cases support significantly high oral cancer incidence among adults who smoke and a lower risk of oral cancer incidence among never users, quitters, users of ST, and former smokers who now use ST compared to cigarettes. Future studies with detailed control of tobacco history and other relevant confounders are needed to confirm these findings.

Health literacy and tobacco cessation among hypertensive individuals: A mixed method study

BACKGROUND

Hypertension and tobacco addiction are two major public health challenges in India that frequently coexist. About 30% of Indian adults have hypertension, while over one-fourth use some form of tobacco. So, the present study aimed to determine the prevalence and patterns of tobacco consumption and identify associated socio-demographic factors among hypertensive patients in urban India and also further explored patient perspectives regarding tobacco use through qualitative interviews.

MATERIALS AND METHODS

This mixed-method study was conducted among 305 hypertensive adults recruited from an urban tertiary hospital using interviewer-administered questionnaires. Additionally, 15 tobacco-consuming patients were purposively sampled for in-depth interviews regarding perceptions and behaviors related to tobacco. Descriptive statistics and multi-variable logistic regression models were applied for quantitative analysis and thematic analysis for qualitative data.

RESULTS

The prevalence of ever tobacco use among hypertensive patients was 21%. Smokeless tobacco was the predominant form used. Male gender, urban locality, illiteracy, and lack of knowledge about tobacco hazards had a higher likelihood of tobacco consumption. Qualitative interviews provided complementary insights into triggers like peer influences and stress, barriers to quitting including withdrawal effects and system gaps, and participant perspectives on facilitating cessation.

CONCLUSION

Tobacco consumption among hypertensives is higher than national averages. Tailored educational, motivational, and policy-level interventions addressing gaps in knowledge, risk perceptions, addiction behaviors, and cessation support systems can enable the promotion of tobacco abstinence and hypertension control in this vulnerable sub-group. The multi-method data provide actionable inputs for planning targeted control and prevention strategies addressing this dual burden.

Evolving trends in oral cancer burden in Europe: a systematic review

Introduction

Oral cavity cancer (OCC), primarily oral squamous cell carcinoma (OSCC), is a growing concern in Europe, particularly among younger populations. Preventable lifestyle factors and social determinants of health contribute significantly to the disease burden. Limited access to healthcare and delayed diagnoses further complicate treatment and reduce survival rates.

Methods

This systematic literature review adhered to PRISMA guidelines to explore trends in OSCC epidemiology, etiology, diagnosis, treatment, and survival across Europe. A comprehensive search strategy using PubMed, GLOBOCAN data, and the EUROCARE-5 study identified relevant articles focusing on human populations in Europe with a primary interest in OSCC epidemiology. Only peer-reviewed publications in English with full-text access were included.

Results

This study investigated the burden of OSCC across Europe, revealing variations in incidence, mortality, and prognosis. Eastern and Central Europe displayed the highest burden. Males exhibited a significantly higher risk compared to females. Age-related disparities existed in life expectancy and time to achieve favorable outcomes. HPV emerged as a growing risk factor for oropharyngeal cancer. Public health strategies should target modifiable risk factors and improve early detection.

Conclusion

This review reveals concerning disparities in European OSCC. Region, sex, and age all influence burden and prognosis. Future research should focus on controlling risk factors and personalized medicine to optimize treatment. This will lead to a Europe with reduced OSCC incidence and demonstrably better patient outcomes.

Histologic spectrum and outcome of Human papillomavirus (HPV)-associated oral cavity squamous cell carcinoma: a single center experience and a survey of The Cancer Genome Atlas (TGCA) cohort

While high-risk human papillomavirus (HPV) serves as an essential pathogen and an important prognostic and predictive biomarker for oropharyngeal squamous cell carcinoma, it occurs at low frequency (2.2-6%) in oral cavity squamous cell carcinoma (OCSCC). To date, the pathologic features of HPV-associated OCSCC (HPV( +)-OCSCC) have been sparsely reported and its prognosis is not well-defined. We herein described detailed clinicopathologic features and outcomes of a retrospective series of 27 HPV( +)-OCSCC, including 13 from Memorial Sloan Kettering Cancer Center (MSKCC) and 14 from The Cancer Genomic Atlas program (TCGA). The frequency of HPV positivity in OCSCC was 0.7% in MSKCC cohort and 4.9% in TCGA cohort. Although HPV( +)-OCSCC was predominantly non-keratinizing (in 81%) with various degree of maturation, its histologic spectrum was expanded to include keratinizing subtype (19%), adenosquamous carcinoma (7%), and papillary architecture (subtype, 7%). HPV( +)-OCSCC predominantly affected male patients (male:female ratio = 12.5:1) and (ex) smokers (77%). It might occur in mandibular mucosa, floor of mouth, tongue, retromolar trigone, buccal mucosa, maxillary mucosa, or hard palate. In oral cavity, positivity of HPV by RNA in situ hybridization was required, and p16 immunohistochemistry alone was insufficient to confirm the HPV + status. The positive predictive value of p16 immunopositivity in detecting HPV infection was 68%. HPV-positivity did not appear to affect outcomes, including disease specific survival and progression free survival in OCSCC.

Comparative proteomic analysis of saliva from chewing tobacco users and oral cancer patients reveals shared biomarkers: A case control observational study

OBJECTIVE

The aim of this study was to compare the salivary proteomic profile of smokeless tobacco users with that of non-users and oral cancer patients using Liquid Chromatography-Mass Spectrometry/ Mass Spectrometry (LC-MS/MS).

METHODS

Saliva samples from 65 participants were collected in three groups: control (25 participants), smokeless tobacco users (25 participants), and oral cancer (15 participants).

RESULTS

The analysis revealed 343 protein groups with significantly altered abundance in the saliva samples (P < 0.05). Among these, 43 out of 51 dysregulated proteins in the smokeless tobacco group were also dysregulated in the oral cancer group. Notably, Apolipoprotein A1 (ApoA1) and Pon1 were found to be significantly increased in both smokeless tobacco users and oral cancer patients (p < 0.05). Furthermore, six out of the 20 most significantly altered proteins were mitochondrial proteins, and all of these were decreased relative to controls in both smokeless tobacco users and cancer samples.

CONCLUSION

The proteomic profile of users of chewing (smokeless) tobacco (SLT) shows substantial overlap in the altered pathways and dysregulated proteins with those altered in oral cancer samples, suggesting that SLT use induces a shift toward an oncogenic state. Specifically indicated pathways included blood microparticles, platelet α-granules and protease inhibitors as well as indicators of oxidative stress and exogenous compound processing. What differentiates oral cancer samples from SLT users is enrichment of alterations related to cytoskeletal organisation and tissue remodelling.

CLINICAL SIGNIFICANCE

The findings emphasize the importance of salivary proteomic profiles because changes in certain proteins may be indicators for early oral cancer identification and risk assessment in smokeless tobacco users.

Association of Tobacco Use and Cancer Incidence in India: A Systematic Review and Meta-Analysis

PURPOSE

To estimate the strength of the association between tobacco use and cancer incidence among the Indian population.

MATERIALS AND METHODS

Data from PubMed, Embase, and Virtual Health Library were searched from inception of databases till April 30, 2022. There were no restrictions except for English language and human study. Case-control and cohort studies on cancer incidence in relation to tobacco use were selected. Data were extracted independently by two investigators, and discrepancies were resolved by a third reviewer. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. The quality assessment was done using the Newcastle Ottawa Scale.

RESULTS

The majority were case-control designs (60, 89.6%), covering diverse geographic regions, with Maharashtra (18, 30%) and Kerala (12, 20%) being the most studied. Pooled effect sizes were calculated using the random-effects model, and forest plots were generated. The risk of any cancer associated with smoked and smokeless tobacco was 2.71 (95% CI, 2.25 to 3.16) and 2.68 (95% CI, 2.22 to 3.14), respectively, indicating similar risks. Gender-wise, smoked tobacco had an association of 2.35 (95% CI, 2.05 to 2.65) for males, whereas for smokeless tobacco, it was 1.77 (95% CI, 1.47 to 2.07) for males and 2.34 (95% CI, 1.26 to 3.42) for females. Regardless of gender, tobacco type, and affected body parts, the risk of cancer due to tobacco use was consistent in the Indian population. Site-specific analysis showed higher risks of respiratory system cancers of 4.97 (95% CI, 3.62 to 6.32) and head and neck cancers of 3.95 (95% CI, 3.48 to 4.42).

CONCLUSION

This study underscores that both smoked and smokeless tobacco are equally harmful to human health among the Indian population, providing insights for stakeholders and policymakers to arrive at tobacco-specific interventions.

The Diversity in Tobacco Use Among Women of Reproductive Age (15-49 Years) in Pakistan: A Secondary Analysis of a Multiple Indicator Cluster Survey 2016-2018

INTRODUCTION

Tobacco use in women of reproductive age group (15-9 years) may contribute to poor maternal and child health outcomes. We estimated the prevalence of smokeless tobacco (ST), cigarette, and waterpipe use among these women in Pakistan and explored associations with socio-economic differences and birth weights after recent childbirths (past 2 years).

AIMS AND METHODS

We used the Multiple Indicator Cluster Surveys datasets from three provinces in Pakistan. Prevalence was generated for current use of tobacco among women with recent childbirth (WWRC) and without recent childbirth (WWoRC). We further compared socio-economic status and birth weights between tobacco users and non-users.

RESULTS

The prevalence of current ST use was 1.4% and 2.5%, and waterpipe smoking was 1.2% and 1.8%, in WWRC and WWoRC, respectively. ST use varied across Pakistan's provinces by 13 percentage points in WWRC and WWoRC while waterpipe smoking by 10 and 15 percentage points, respectively. The odds of using any form of tobacco were significantly lower with higher levels of education or wealth index. Compared to children born to mothers who did not use tobacco, the birth weight of children born to mothers who smoked waterpipe was on average 0.83 kg (95% CI -1.6 to -0.1) lower whereas it was 0.33 kg (95% CI -0.9 to 0.3) higher for ST users.

CONCLUSIONS

Tobacco use among women of reproductive age in Pakistan varied significantly based on province and tobacco type. Waterpipe smoking was associated with a reduction in birth weight. Raising awareness of the harms of tobacco use among women of reproductive age and targeting interventions in high-burden regions of Pakistan should be prioritized.

IMPLICATIONS

The prevalence of current smokeless tobacco use and waterpipe smoking varied significantly in Pakistan (~13 and ~15 percentage points, respectively) among women of reproductive age, and there seems to be little change in tobacco use behavior around pregnancy and early motherhood. The study highlights a need to better understand the prevalence of tobacco use in Pakistan, and further contextual research is warranted to understand the reasons for such high tobacco use in certain areas. This information highlights the need for improving current tobacco control interventions and policies, including measures that could help reduce its use and prevent its uptake. Furthermore, compared to children born to mothers who did not use any form of tobacco, we found a statistically significant difference (830 g) in birth weight for babies born to mothers who at the time of the interview smoked waterpipe and a non-statistically significant difference of about 330 g for children born to mothers who at the time of the interview used smokeless tobacco. In addition to our findings, some literature suggests the association of waterpipe smoking with low birth weight. A possible explanation could be the exposure to smoke that contains toxicants from the tobacco product itself in addition to the burning of charcoal, which is required when using waterpipe. Waterpipe smoking also results in high exposures to carbon monoxide and polycyclic aromatic hydrocarbons, which are known to be carcinogenic and teratogenic. In terms of smokeless tobacco use, further research is warranted to understand its impact on birth outcomes through longitudinal studies accounting for diverse products, its constituents and the amount of consumption.

Smokeless tobacco consumption among women of reproductive age: a systematic review and meta-analysis

Smokeless tobacco (SLT) poses many negative health impacts. Despite its longstanding presence in societies across the world, the health implications of SLT have only been rigorously studied in recent decades. This systematic review and meta-analysis aimed to consolidate existing research to provide a comprehensive understanding of the global prevalence of SLT use among women of reproductive age. Relevant articles were extracted from databases such as PubMed, EMBASE, Web of Science, and Scopus from their inception until November 11, 2023. Observational studies reporting the number of SLT users among women of reproductive age were included. The quality of the studies was assessed using the Joanna Briggs Institute (JBI) tool. The meta-analysis used a random-effects model to determine SLT prevalence, supported by statistical tools like forest plots, I2 statistics, and sensitivity analyses to ensure the accuracy and comprehensiveness of the results. All statistical analyses were performed in R version 4.3. From 10 studies involving 2,053,667 participants, a pooled prevalence for SLT use among women of reproductive age was found to be 9.3% (95% CI: 0.038 to 0.21), with significant heterogeneity among studies (I2 = 100%). Publication bias was suspected among the studies. Sensitivity analysis and subgroup analysis couldn't resolve the heterogeneity. Our analysis shows a significant prevalence of SLT use in women of reproductive age, especially in low socioeconomic and developing countries like India, Pakistan, and Nepal. For women of reproductive age, the use of smokeless tobacco (SLT) can lead to infertility, pregnancy complications, and adverse fetal outcomes, including low birth weight and preterm birth. The results highlight the necessity for specific public health measures and policy changes to decrease SLT consumption among reproductive-age women. Further studies are needed to investigate the reasons behind SLT usage in this group and to assess the impact of intervention strategies, to guide more effective public health initiatives and policies.

Trend over time on knowledge of the health effects of cigarette smoking and smokeless tobacco use in Bangladesh: Findings from the International Tobacco Control Policy Evaluation Bangladesh Surveys

INTRODUCTION

Cigarette smoking and smokeless tobacco (ST) use are prevalent in Bangladesh. This longitudinal study examined how knowledge of the health effects of smoking and ST use in Bangladesh has changed overtime with the country's acceleration of tobacco control efforts.

METHODS

Data were analysed from the International Tobacco Control Survey, a nationally representative longitudinal study of users and non-users of tobacco (aged 15 and older) in Bangladesh, across four waves conducted in 2009 (n = 4378), 2010 (n = 4359), 2012 (n = 4223) and 2015 (n = 4242). Generalised estimating equations assessed the level of knowledge about harms of tobacco use across four waves. Multivariable logistic regressions assessed whether knowledge of health effects from cigarette smoking and ST use in 2015 differed by user group.

RESULTS

In 2015 survey, most tobacco users were aware that cigarette smoking causes stroke (92%), lung cancer (97%), pulmonary tuberculosis (97%) and ST use causes mouth cancer (97%) and difficulty in opening mouth (80%). There were significant increases in the total knowledge score of smoking related health harm from 2010 to 2012 (mean difference = 0.640; 95% confidence interval [CI] 0.537, 0.742) and 2012 to 2015 (mean difference = 0.555; 95% CI 0.465, 0.645). Participants had greater odds of awareness for ST health effects from 2010 to 2015.

DISCUSSION AND CONCLUSIONS

The results suggest that increasing efforts of awareness policy interventions is having a positive effect on tobacco-related knowledge in Bangladesh. These policy initiatives should be continued to identify optimal methods to facilitate behaviour change and improve cessation of smoking and ST use.

Clinical data, survival, and prognosis of 426 cases of oropharyngeal cancer: a retrospective analysis

OBJECTIVE

To determine factors influencing survival and prognosis of HPV-related and non-related oropharyngeal cancer.

METHODS

Subjects were determined from the three hospitals in Anhui province of China between 2015 and 2020. Paraffin-embedded specimens from participants' tissues were analyzed, and the subjects were classified as P16 + and P16 - cases using immunohistochemical staining for P16 protein.

RESULTS

A total of 426 patients with oropharyngeal cancer were recruited in this study; 108 cases were found to be P16 + . The subjects were treated with the three regimens: surgery/radiotherapy/chemotherapy (SRCT), radiotherapy/chemotherapy (RCT), and surgery/chemotherapy (SCT). There were no statistically significant differences in the survival rates within the P16 + or P16 - groups between the three treatment regimens (P > 0.05). The 1-, 3-, and 5-year survival rates for P16 + and P16 - groups were statistically different (P < 0.05). Multivariate analysis showed that age, physical health status, smoking, and alcohol abuse were independent risk factors affecting the prognosis of P16 + cases, while pathological grading and TNM staging were independent risk factors affecting the P16 - cases.

CONCLUSION

The etiology, pathogenesis, survival status, and prognostic factors of HPV-related oropharyngeal cancer are very different from those of traditional oropharyngeal cancer. Thus, HPV-related oropharyngeal cancer could be classified as a separate type of disease. This distinction could be of great significance for treatment, prevention, and prognostication of oropharyngeal cancer.

Efficacy of smokeless tobacco for smoking cessation: a systematic review and meta-analysis

OBJECTIVE

Smoking remains prevalent in many countries despite rigorous tobacco control strategies. The use of Swedish snus, a type of low-nitrosamine smokeless tobacco, has been promoted as a tobacco harm reduction strategy.

DATA SOURCES AND STUDY SELECTION

Three databases were searched for studies that assessed the effectiveness of snus in promoting smoking abstinence. A total of 28 studies were reviewed (5 randomised controlled trials (RCTs), 7 longitudinal and 16 cross-sectional studies).

DATA EXTRACTION

Separate meta-analyses were conducted by study type, pooling effect estimates where outcome measures and design were sufficiently comparable. Study details and quality assessment (Risk of Bias 2 for RCTs, Newcastle-Ottawa Scale for observational studies) are provided for each study.

DATA SYNTHESIS

While the meta-analysis of RCTs did not show a significant association between snus use and smoking cessation (risk ratio (RR)=1.33, 95% CI 0.71 to 2.47 and RR=0.62, 95% CI 0.27 to 1.41), the results of the meta-analysis of longitudinal cohort studies (RR=1.38, 95% CI 1.05 to 1.82, p=0.022) and cross-sectional studies (OR=1.87, 95% CI 1.29 to 2.72, p=0.001) indicated that use of snus was associated with an increased likelihood of quitting or having quit smoking. There was significant heterogeneity in the cross-sectional studies, and leave-one-out analysis indicated that the longitudinal cohort results were driven by one study. Most studies examined were subject to an elevated risk of bias.

CONCLUSION

There is weak evidence for the use of snus for smoking cessation. Better RCTs and longitudinal studies are needed; meanwhile, existing cessation aids may be better placed than snus to promote abstinence.

From cultivation to cancer: formation of N-nitrosamines and other carcinogens in smokeless tobacco and their mutagenic implications

Tobacco use is a major cause of preventable morbidity and mortality globally. Tobacco products, including smokeless tobacco (ST), generally contain tobacco-specific N-nitrosamines (TSNAs), such as N'-nitrosonornicotine (NNN) and 4-(methylnitrosamino)-1-(3-pyridyl)-butanone (NNK), which are potent carcinogens that cause mutations in critical genes in human DNA. This review covers the series of biochemical and chemical transformations, related to TSNAs, leading from tobacco cultivation to cancer initiation. A key aim of this review is to provide a greater understanding of TSNAs: their precursors, the microbial and chemical mechanisms that contribute to their formation in ST, their mutagenicity leading to cancer due to ST use, and potential means of lowering TSNA levels in tobacco products. TSNAs are not present in harvested tobacco but can form due to nitrosating agents reacting with tobacco alkaloids present in tobacco during certain types of curing. TSNAs can also form during or following ST production when certain microorganisms perform nitrate metabolism, with dissimilatory nitrate reductases converting nitrate to nitrite that is then released into tobacco and reacts chemically with tobacco alkaloids. When ST usage occurs, TSNAs are absorbed and metabolized to reactive compounds that form DNA adducts leading to mutations in critical target genes, including the RAS oncogenes and the p53 tumor suppressor gene. DNA repair mechanisms remove most adducts induced by carcinogens, thus preventing many but not all mutations. Lastly, because TSNAs and other agents cause cancer, previously documented strategies for lowering their levels in ST products are discussed, including using tobacco with lower nornicotine levels, pasteurization and other means of eliminating microorganisms, omitting fermentation and fire-curing, refrigerating ST products, and including nitrite scavenging chemicals as ST ingredients.

Differential Expression Profile of Salivary oncomiRNAs among Smokeless Tobacco Users

OBJECTIVE

 The aim of this study was to evaluate the expression of selected salivary oncomiRNAs among smokeless tobacco users and nonsmokers.

MATERIALS AND METHODS

 Twenty-five subjects with chronic smokeless tobacco habit (> 1 year) and 25 nonsmokers were selected for this study. MicroRNA was extracted from saliva samples using the miRNeasy Kit (Qiagen, Hilden, Germany). The forward primers used in the reactions include hsa-miR-21-5p, hsa-miR-146a-3p, hsa-miR-155-3p, and hsa-miR-199a-3p. Relative expression of miRNAs was calculated using the 2-ΔΔCt method. Fold change is calculated by raising 2 to the power of the negative ΔΔCT value.

STATISTICAL ANALYSIS

 Statistical analysis was carried out using GraphPad Prism 5 software. A p-value less than 0.05 was considered statistically significant.

RESULTS

 The four tested miRNAs were found overexpressed in saliva of subjects with smokeless tobacco habit when compared with saliva from nontobacco users. miR-21 expression was 3.74 ± 2.26 folds higher among subjects with smokeless tobacco habit compared to nontobacco users (p < 0.01). The expression for miR-146a (5.56 ± 8.3 folds; p < 0.05), miR-155 (8.06 ± 23.4 folds; p < 0.0001) and miR-199a (14.39 ± 30.3 folds; p < 0.05) was significantly higher among subjects with smokeless tobacco habit.

CONCLUSION

 Smokeless tobacco leads to salivary overexpression of the miRs 21, 146a, 155, and 199a. Monitoring the levels of these four oncomiRs may provide insight about the future development of oral squamous cell carcinoma, especially in patients with smokeless tobacco habits.

How do Smokers in a Snus-Prevalent Society Consider E-cigarettes, Snus, and Nicotine Replacement Therapy Products as Relevant Replacements for Cigarettes in the Event They Should Stop Smoking?

INTRODUCTION

Around 50 percent of the tobacco in Norway is consumed in the form of snus, a smokeless oral tobacco. We examined Norwegian smokers' openness, and thereby the potential reach, to use e-cigarettes, nicotine replacement therapy products (NRT), and snus in the event of quitting smoking, in a society where snus use is common.

METHODS

Using data from an online survey of 4073 smokers from 2019 to 2021, we calculated predicted probabilities of smokers' being open, undecided, and not open to use e-cigarettes, snus, and NRT in the event they should quit smoking.

RESULTS

Among daily smokers, the probability of being open to use e-cigarettes in the event of quitting smoking was .32. The corresponding probabilities for using snus and NRT were .22 and .19. Snus was the product with the highest probability of not being open (.60). NRT had the highest probability of being undecided (.39). Among smokers who had never used e-cigarettes or snus, the probabilities of being open were .13 for e-cigarettes, .02 for snus and .11 for NRT.

CONCLUSIONS

In a snus-friendly norm climate where smokers have traditionally used snus as an alternative to cigarettes, the probability of using e-cigarettes in the event of smoking cessation was higher compared to both snus and NRT. However, among smokers who had never used e-cigarettes or snus, the likelihood of being open to use of NRT was similar to e-cigarettes, and higher than snus, which suggests that NRT may still play a role in smoking cessation.

IMPLICATIONS

In a snus-prevalent country in the endgame phase of the cigarette epidemic, where robust infrastructure for tobacco control in combination with the availability of snus has reduced smoking to a minimum, the remaining smokers seem to prefer e-cigarettes to snus if they should quit smoking. This indicates that availability of several nicotine alternatives might increase the likelihood of a future product replacement within the small group of remaining smokers.

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.

The potential roles of cigarette smoke-induced extracellular vesicles in oral leukoplakia

BACKGROUND

The onset of oral leukoplakia (OLK), the most common oral lesion with a high risk of malignant transformation, is closely associated with the exposure of cigarette smoke. Cigarette smoke is a complicated mixture of more than 4500 different chemicals including various oxidants and free radical, which contributes to the onset of immune and inflammatory response or even carcinogenesis. Recent studies have proved that the exposure of cigarette smoke leads to the onset and aggravation of many diseases via significantly changed the production and components of extracellular vesicles. The extracellular vesicles are membrane-enclosed nanosized particles secreted by diverse cells and involved in cell-cell communication because of their ability to deliver a number of bioactive molecules including proteins, lipids, DNAs and RNAs. Getting insight into the mechanisms of extracellular vesicles in regulating OLK upon cigarette smoke stimulation contributes to unravel the pathophysiology of OLK in-depth. However, evidence done on the role of extracellular vesicles in cigarette smoke-induced OLK is still in its infancy.

MATERIALS AND METHODS

Relevant literatures on cigarette smoke, oral leukoplakia and extracellular vesicles were searched in PubMed database.

CONCLUSIONS

In this review, we summarize the recent findings about the function of extracellular vesicles in the pathogenesis of cigarette smoke-induced diseases, and to infer their potential utilizations as diagnostic biomarkers, prognostic evaluation, and therapeutic targets of OLK in the future.

Social determinants of sex disparities in cancer in Southeast Asia

Sex disparities in cancer exist along the cancer spectrum, ranging from genomic predisposition and behavioral risk factors to access to screening, diagnostics, treatment, and survivorship care. A growing body of research is studying the biological underpinnings of these differences, from cancer risk to tumor biology to treatment response. It is well known, however, that the social determinants of health play a large role across the cancer disease continuum, which encompasses risk, prevention, diagnosis, treatment, survivorship, rehabilitation, and palliative care. Less literature focuses on the gendered disparities that are epidemiologic in nature, especially in Southeast Asia (SEA), a diverse region that is home to nearly 670 million people, where most are lower middle income countries, and where socioeconomic and cultural factors increase cancer risk for women. In this review, we highlight the social drivers of gendered disparities, namely the geographic, environmental, sociocultural, economic, and political forces that contribute to the increased mortality and poorer health outcomes in the region.

Areca nut and smokeless tobacco exposure induces micronucleus, other nuclear abnormalities and cytotoxicity in early chick embryo

Areca nut (AN) and smokeless tobacco (SLT) are indiscriminately consumed among the populations of Southeast and South Asian countries, even by women during the gestational period. This study aimed to investigate the genotoxic and cytotoxic potentials of AN and Sadagura (SG), a unique homemade SLT preparation, alone and in combination in early chick embryos. Fertile white leghorn chicken eggs were randomly divided into five treatment groups: vehicle control, positive control (Mitomycin C, 20 μg/egg), AN, SG, and AN+SG. AN, SG, and AN+SG were given at dosages of 0.125, 0.25, and 0.5 mg/egg. The hen's egg test for micronucleus induction (HET-MN) was performed in chick embryos to evaluate the genotoxic potential of the test agents. Furthermore, the cytotoxic potential was assessed by studying erythroblast cell populations and the polychromatic erythrocytes (PCEs) to normochromatic erythrocytes (NCEs) ratio. Our results indicated a significant increase (p < .001) in MN frequency and other nuclear abnormalities, suggesting the potential of AN and SG to cause genotoxicity. Also, AN and SG exposure alone and in combination considerably altered the erythroblast cell population (%) and the PCE to NCE ratio in all the treatment periods. Our findings established the genotoxic and cytotoxic potential of both AN and SG alone and in combination during early embryonic development in the chick embryo.

The Potential Association between E2F2, MDM2 and p16 Protein Concentration and Selected Sociodemographic and Clinicopathological Characteristics of Patients with Oral Squamous Cell Carcinoma

BACKGROUND

E2F transcription factor 2 (E2F2), murine double minute 2 (MDM2) and p16 are some of the key proteins associated with the control of the cell cycle. The aim of this study was to evaluate E2F2, MDM2 and p16 concentrations in the tumour and margin samples of oral squamous cell carcinoma and to assess their association with some selected sociodemographic and clinicopathological characteristics of the patients.

METHODS

The study group consisted of 73 patients. Protein concentrations were measured by enzyme-linked immunosorbent assay (ELISA).

RESULTS

There were no statistically significant differences in the levels of E2F2, MDM2 or p16 in the tumour samples as compared to the margin specimens. We found that patients with N0 showed significantly lower E2F2 concentrations than patients with N1 in the tumour samples and the median protein concentration of E2F2 was higher in HPV-negative patients in the tumour samples. Moreover, the level of p16 in the margin samples was lower in alcohol drinkers as compared to non-drinkers. Similar observations were found in concurrent drinkers and smokers compared to non-drinkers and non-smokers.

CONCLUSIONS

E2F2 could potentially promote tumour progression and metastasis. Moreover, our results showed a differential level of the analysed proteins in response to alcohol consumption and the HPV status.

Smokeless tobacco utilization among tribal communities in India: A population-based cross-sectional analysis of the Global Adult Tobacco Survey, 2016–2017

Introduction

Evidence on smokeless tobacco use is scarce among indigenous communities, with the available literature based either on a specific tribe or on a particular region. Therefore, we aimed to estimate the prevalence of smokeless tobacco and assess its correlation among tribal communities in India.

Methods

We utilized data from the Global Adult Tobacco Survey-2 conducted in 2016–2017. A total of 12,854 tribal people aged &gt;15 years were included in this study. The utilization of smokeless tobacco was estimated using the weighted proportion, and its correlates were assessed by multivariable logistic regression reported as an adjusted odds ratio (AOR) with a 95% confidence interval.

Results

The prevalence of smokeless tobacco use was 32%. Participants aged 31–45 years [AOR: 1.66 (1.37–2.00)], who were men [AOR: 2.37 (1.94–1.90)], and who were daily wage/casual laborers [AOR: 5.32 (3.39–8.34)] were observed to have a significant association with smokeless tobacco. Willingness and attempt to quit smokeless tobacco were higher in Eastern India (31.2%) and central India (33.6%), respectively.

Discussion

We observed one-third of the tribal individuals used smokeless tobacco in India. Tobacco control policies should prioritize men, rural residents, and individuals with fewer years of schooling. Culturally appropriate and linguistically tailored messages are required for behavioral change communication.

Efficacy of 5-aminolevulinic acid-mediated photodynamic therapy in patients with nicotine stomatitis

AIM

This study aimed to treat smoker's palate (SP) using 5-aminolevulinic acid (5-ALA)-mediated photodynamic therapy (PDT).

METHODS

A total of 24 patients with SP were divided into two groups: group-I (test group; n = 12); and group-II (control group; n = 12). Group-I patients were treated with 5-ALA-mediated PDT, while group-II patients were advised to cease the smoking habit during the entire duration of the study and later. PDT was repeated on days 3, 7, and 14 (i.e., a total of four sittings including day 0 [baseline]). Later, the participants were called for follow-up after week-4 (1st follow-up), week-6 (2nd follow-up), and week-8 (3rd follow-up) after the completion of the treatment. The SPSS version 22.0 was used for data analysis.

RESULTS

Group-I patients showed a statistically significant improvement when all three time points were assessed (p < 0.0001). Similarly, the same trend was observed in the group-II participants (p < 0.001), however, the difference between both groups (i.e., group-I [test group] and group-II [control group]) was larger.

CONCLUSION

The findings of this clinical trial indicated a promising and satisfactory decrease in the clinical features of the smoker's palate without any adverse impacts utilizing 5-aminolevulinic acid-mediated photodynamic therapy. Hence, 5-ALA-mediated PDT appeared to be a promising treatment option together with smoking cessation.

Imaging Recommendations for Diagnosis, Staging, and Management of Oral Cancer

Oral cavity cancers contribute to a majority of cancers in India. Clinical examination alone cannot determine the deeper extent of the disease; therefore, need for cross-sectional imaging including computed tomography and magnetic resonance imaging becomes indispensable for pre-treatment evaluation to decide optimal plan of management. Oral cavity squamous cell cancers (OSCC) can be treated with surgery alone, whereas deep muscle, neurovascular, osseous, or nodal involvement on imaging suggests advanced disease that requires a combination of surgery, radiation, and/or chemotherapy. Because of the complex anatomy of the oral cavity and its surrounding structures, imaging is crucial for locoregional staging and early detection of distant metastases. Imaging plays indispensable role not only in diagnosis but also in planning the management. An optimal guideline paper for developing countries like India is lacking that not only helps standardize the management but will also assist oncologists make reasonable decisions and reduce the unnecessary imaging. This imaging guideline paper will discuss the optimal imaging in diagnosis and management OSCC for Indian subcontinent.

Histologic Analysis of Buccal Graft Quality Stratified by Tobacco Use in Patients Undergoing Substitution Urethroplasty

OBJECTIVE

To determine if there are histologic differences relative to tobacco exposure in buccal mucosa. Substitution urethroplasty outcomes may be worse in tobacco users and we investigate if the buccal graft is inherently damaged due to chronic tobacco exposure.

METHODS

Subjects undergoing substitution urethroplasty with buccal graft harvest were prospectively consented in this IRB approved study. Subjects with poor dentition were excluded. A detailed tobacco use history was obtained. Cotinine testing was performed day of surgery to confirm or exclude active tobacco use. Trimmed portions of harvested graft were sent for tissue processing. Standard hematoxylin and eosin staining was performed. A single blinded pathologist performed analysis of the slides. Using a scale of none, mild, moderate, or severe slides were analyzed for cytologic atypia, architectural complexity, inflammation, and keratinization. Evidence of vascular damage was noted and the type of inflammation if present was classified.

RESULTS

Twenty-five buccal grafts were analyzed. No evidence of vascular damage or cytologic atypia were noted in any grafts. While mild architectural complexity and mild inflammation, typically lymphocytic, were noted in several of the buccal mucosa sections, this did not appear to correlate with tobacco exposure. The majority of grafts demonstrating increased keratinization correlated with significant tobacco exposure, but this was not consistently noted in all those with tobacco use.

CONCLUSIONS

Buccal mucosa in patients with tobacco exposure did not show significant histologic alterations. Outcomes of substitution urethroplasty may be more impacted by persistent systemic exposure causing local ischemia as opposed to the graft tissue itself.

Peripubertal Nutritional Prevention of Cancer-Associated Gene Expression and Phenotypes

Breast cancer (BC) is a nearly ubiquitous malignancy that effects the lives of millions worldwide. Recently, nutritional prevention of BC has received increased attention due to its efficacy and ease of application. Chief among chemopreventive compounds are plant-based substances known as dietary phytochemicals. Sulforaphane (SFN), an epigenetically active phytochemical found in cruciferous vegetables, has shown promise in BC prevention. In addition, observational studies suggest that the life stage of phytochemical consumption may influence its anticancer properties. These life stages, called critical periods (CPs), are associated with rapid development and increased susceptibility to cellular damage. Puberty, a CP in which female breast tissue undergoes proliferation and differentiation, is of particular interest for later-life BC development. However, little is known about the importance of nutritional chemoprevention to CPs. We sought to address this by utilizing two estrogen receptor-negative [ER(-)] transgenic mouse models fed SFN-containing broccoli sprout extract during the critical period of puberty. We found that this treatment resulted in a significant decrease in tumor incidence and weight, as well as an increase in tumor latency. Further, we found significant alterations in the long-term expression of cancer-associated genes, including p21, p53, and BRCA2. Additionally, our transcriptomic analyses identified expressional changes in many cancer-associated genes, and bisulfite sequencing revealed that the antiproliferation-associated gene Erich4 was both hypomethylated and overexpressed in our experimental group. Our study indicates that dietary interventions during the CP of puberty may be important for later-life ER(-) BC prevention and highlights potential important genetic and epigenetic targets for treatment and study of the more deadly variants of BC.

Common assumptions in tobacco control that may not hold true for South-East Asia

Tobacco is a threat to public health in South-East Asia and its control should be a priority. However, many common assumptions about tobacco control may not hold true for the region and can misdirect policy. The substantial health risks associated with smokeless tobacco have been largely misunderstood and neglected. The syndemic association between tuberculosis and tobacco has also been overlooked. Similarly, less attention has been paid to address second-hand smoke exposure of pregnant women to indoor smoking (caused predominantly by men). On the other hand, our poor understanding of the diverse tobacco supply chain has been blocking progress in tobacco control. Finally, the rising popularity of electronic cigarettes has thrown new challenges; many governments, concerned for its youth, have banned such products. We argue for a nuanced approach to tobacco control in South-East Asia. We also encourage a wider debate in public health, where other established assumptions may be hampering progress.

Awareness and knowledge of risk factors associated with oral cancer among military personnel in Nigeria

Background

The military lifestyle has been reported to increase the risk of this population group to the development of oral cancer.

Aim

This study aimed to determine the awareness and knowledge of oral cancer in a population of soldiers to acquire data for establishing an educational program for units of the Nigerian Army in oral cancer prevention and monitoring. The study was conducted in the dental center of 82 Division Military Hospital, Nigerian Army, Enugu, Nigeria. A cross-sectional survey was performed using a pre-tested self-administered questionnaire.

Materials and Methods

Questions relating to oral cancer awareness, knowledge of causes, and relationship to certain habits, treatment options, and desirability of screening opportunities for oral cancer were asked. Soldiers attending the military hospital, dental center, were chosen randomly for the study.

Results

Three hundred soldiers were surveyed. The mean age of those surveyed was 37.5 and had spent an average of 11-15 years in the Army. The majority of the soldiers (80.7%) have heard of cancer; the types most known were breast (75%), skin (30%), and lung cancer (28.3%). Of the 300 soldiers surveyed, 15.3% knew about oral cancer, with 41.3% of these able to identify cigarette smoking and (26%) alcohol consumption as possible risk factors associated with oral cancer. The majority believed that cancer was caused by some form of supernatural phenomenon.

Conclusion

Oral cancer awareness is low among soldiers in the Nigerian Armed Forces, and strategies to increase awareness should be developed.

A Comparative Analysis of Dominant Dietary Patterns in Patients with and without Oral Squamous Cell Carcinoma

Background

As a modifiable risk factor, nutrition plays a pivotal role in the prevention or delay of oral squamous cell carcinoma (OSCC). This study was aimed to investigate and compare the dominant dietary patterns in the patients with and without OSCC.

Materials and Methods

This case-control study evaluated the usual dietary intake of 80 cases and 120 controls during 2019-2020 using the 117-item Food Frequency Questionnaire, with confirmed validity and reliability. Factor analysis was used to detect the dominant dietary patterns. Data analysis was done by SPSS (version 21) using the Chi-square test, ANOVA, logistic regression analysis, and independent t-test (P < 0.05).

Results

Three dietary patterns were identified, including the western dietary pattern, health dietary pattern, and traditional dietary pattern. The odds ratio (OR) = 1.181 and confidence interval (CI) = 0.671 and 2.082 were found for the western dietary pattern, OR = 1.087 and CI = 0.617 and 1.914 were detected for the healthy dietary pattern, and OR = 0.846 and CI = 0.480 and 1.491 were reported for the traditional dietary pattern. No significant difference was found between the study groups in the dietary pattern and the risk of disease. This relationship remained insignificant after adjustment for the energy intake and confounding factors.

Conclusion

There was no significant relationship between adherence to healthy, traditional, and western dietary patterns and OSCC. Consumption of vegetables and nuts had a protective role against the disease, but risky behaviors such as smoking and alcohol use were directly associated with the incidence of the disease.

Exploring barriers of quitting smokeless tobacco among coronary artery disease patients of India: A qualitative study

BACKGROUND

Cessation of all forms of tobacco is necessary for controlling mortality associated with coronary artery diseases (CADs). In India, smokeless tobacco (SLT) is the most used form of tobacco. With around 60% of the world's smokeless tobacco users living in India, the task of tobacco cessation has become daunting and complicated for Indian researchers and policy makers.

OBJECTIVE

We conducted the present study to understand CAD patients' perspectives towards their SLT use and to identify barriers of SLT cessation.

METHODS

Using a semi-structured interview method, we obtained data from 12 CAD patients who were currently using some form of SLT.

RESULTS

Thematic analysis suggests that CAD patients were unable to quit SLT addiction due to (a) certain socio-environmental factors that support SLT, (b) prevalence of misconceptions about the link between SLT use and their cardiac condition, (c) perceived lower self-efficacy to quit, (d) fatalistic attitude towards health outcomes and (e) substituting addiction with perceived lesser harmful products.

DISCUSSION

The findings reveal that factors responsible for the continuation of SLT usage are multipronged. Current SLT users' perspectives can facilitate the development of effective intervention and rehabilitation programs aimed at de-addiction of cardiac patients.

Reviewing the epidemiology of head and neck cancer: definitions, trends and risk factors

Introduction Head and neck cancer appears to be increasing in incidence, with potential changes in aetiology proposed. This paper aims to provide a narrative overview of the epidemiological literature to describe the disease burden and trends in terms of incidence and mortality both in the UK and globally and to review the evidence on current risk factors.

Methods A search was performed on multiple databases (PubMed and Epistemonikos), applying filters to identify systematic reviews and meta-analyses which investigated head and neck cancer incidence, mortality and risk factors. International and UK cancer registries and sources were searched for incidence and mortality data.

Results Multiple definitions of head and neck cancer are employed in epidemiology. Globally, incidence rates have increased in recent decades, largely driven by oropharyngeal cancer. Mortality rates over the last decade have also started to rise, reflecting the disease incidence and static survival rates. Major risk factors include tobacco smoking alone and in combination with alcohol consumption, betel chewing (particularly in Southeast Asian populations) and the human papillomavirus in oropharyngeal cancer.

Conclusions These epidemiological data can inform clinical and preventive service planning for head and neck cancer.

Head and neck cancer incidence is increasing and is projected to continue to rise, largely driven by increases in oropharyngeal cancer.

Mortality rates have started to increase within the last decade, reflecting a rising incidence and static survival rates.

Major risk factors that are associated with the risk of head and neck cancer are tobacco smoking and tobacco used in combination with alcohol consumption. Human papillomavirus is an additional major risk factor for oropharyngeal cancer. Cancers of the head and neck are clearly socioeconomically patterned but this socioeconomic risk is not entirely explained by smoking and alcohol behaviours.

A call to ban the sale of tobacco products

Tobacco is both toxic and addictive. Mounting evidence shows that tobacco use has a detrimental impact on almost every aspect of human health, causing or worsening deadly public health crises from the cancer epidemic to the COVID-19 pandemic. However, while tobacco use is a threat to both personal and public health, it continues to surge across the world, especially in China and other low- and middle-income countries. To this end, this article argues in favor of using a ban on the sale of all tobacco products as a practical solution to the global tobacco use epidemic. It is our hope that insights provided by our work will inspire swift policy actions in countries such as China and beyond to curb the tide of rising tobacco consumption, so that populations around the world could be better shielded from the pervasive and long-lasting damage that tobacco products cause or compound.

Smokeless tobacco consumption and its association with tobacco control factors in the Western Pacific Region: results from the Global Youth Tobacco Survey 2015-2019

OBJECTIVES

We estimated the prevalence of smokeless tobacco (ST) consumption and its associations with tobacco control factors among school-going youth in 18 Western Pacific Region (WPR) countries.

METHODS

We analyzed school-based Global Youth Tobacco Survey (2014-2019) microdata from 18 WPR countries and estimated weighted prevalence rates of ST consumption, cigarette smoking, and dual use. We used multilevel binary logistic regression to examine the associations of ST consumption and dual use with demographic variables, exposure to pro-tobacco and anti-tobacco factors, national income, and MPOWER indicators.

RESULTS

Data from 58,263 school-going youth were analyzed. The prevalence of past 30-day ST consumption was highest in Kiribati (42.1%), the Marshall Islands (26.1%), Micronesia (21.3%), Palau (16.0%), and Papua New Guinea (15.2%). In adjusted multilevel models, ST consumption and dual use were significantly associated with sex, age, parental smoking, pro-tobacco factors, national income, and MPOWER score. For each unit increase in score for cessation programs, we observed approximately 1.4-fold increases in the odds of youth ST consumption (adjusted odds ratio [aOR], 1.38; 95% confidence interval [CI], 1.15 to 1.66) and dual use (aOR, 1.47; 95% CI, 1.16 to 1.86). Similarly, for each unit increase in score for health-related warnings, the odds of both ST consumption (aOR, 0.47; 95% CI, 0.42 to 0.53) and dual use (aOR, 0.35; 95% CI, 0.30 to 0.42) decreased by approximately 60%.

CONCLUSIONS

The prevalence of youth ST consumption was substantial in the Pacific Islands, exceeding that of cigarette smoking in some countries. Implementing MPOWER measures for ST products could help reduce ST consumption.

UHPLC-MS/MS method for the simultaneous determination of nicotine and tobacco-specific nitrosamines NNN and NNK for use in preclinical studies

A new method was developed and validated for the simultaneous determination of nicotine and tobacco-specific nitrosamines (TSNAs) 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and N-nitrosonornicotine (NNN) in two different tests matrices: porcine buccal epithelium tissue and phosphate buffered saline (PBS) extracts of smokeless tobacco products. The novelty of this work is in the development of a liquid chromatography tandem mass spectrometry method that can provide simultaneous quantification of trace levels of TSNAs and high concentrations of nicotine in biological media. Precision, accuracy, and stability were evaluated during method validation to ensure the method was fit for purpose. Several sample preparation and extraction methods were evaluated to minimize matrix effects and maximize analyte recoveries. The method was accurate in the range of 81.1% - 117%; repeatability was estimated in the range of 1.5% - 13.6% across multiple concentrations. The linear regression correlation coefficient (R2) was greater than 0.9959 for all analytes, and the limit of detection (LOD) was determined for nicotine, NNK, and NNN at 1 ng/mL 0.005 ng/mL, and 0.006 ng/ mL, respectively. Our method was found to be appropriate for the analysis of nicotine, NNN, and NNK in the porcine buccal epithelium and PBS extracts of smokeless tobacco products.

Oral Cancer Risk Assessment for Different Types of Smokeless Tobacco Products Sold Worldwide: A Review of Reviews and Meta-analyses

Smokeless tobacco (SLT) use is a significant cause of lip and oral cavity cancers. Globally, oral cancer prevalence is strongly linked to the types of tobacco products used, their chemical composition, and their pattern of use. Except snus, all SLT products sold in different World Health Organization regions are strongly associated with oral cancer incidence. Shammah showed the highest association OR with 95% confidence intervals (CI; OR, 38.74; 95% CI, 19.50-76.96), followed by oral snuff (OR, 11.80; 95% CI, 8.45-16.49), gutkha (OR, 8.67; 95% CI, 3.59-20.93), tobacco with betel quid (OR, 7.74; 95% CI, 5.38-11.13), toombak (OR, 4.72; 95% CI, 2.88-7.73), and unspecified chewing tobacco (OR, 4.72; 95% CI, 3.13-7.11). Most SLT products containing high levels of carcinogenic tobacco-specific nitrosamines (TSNA) exhibit a high risk of oral cancer. There is an urgent need to frame and implement international policies for oral cancer prevention through legal control of the TSNA levels in all SLT product types.

PREVENTION RELEVANCE

Most smokeless tobacco products sold worldwide, mainly shammah, toombak, gutkha, betel quid with tobacco, and dry snuff, are associated with a high risk of oral cancer. A high concentration of tobacco-specific nitrosamines in smokeless tobacco products is the major causative factor for oral cancer development.

Liquid Biopsy and Circulating Biomarkers for the Diagnosis of Precancerous and Cancerous Oral Lesions

Oral cancer is one of the most common malignancies worldwide, accounting for 2% of all cases annually and 1.8% of all cancer deaths. To date, tissue biopsy and histopathological analyses are the gold standard methods for the diagnosis of oral cancers. However, oral cancer is generally diagnosed at advanced stages with a consequent poor 5-year survival (~50%) due to limited screening programs and inefficient physical examination strategies. To address these limitations, liquid biopsy is recently emerging as a novel minimally invasive tool for the early identification of tumors as well as for the evaluation of tumor heterogeneity and prognosis of patients. Several studies have demonstrated that liquid biopsy in oral cancer could be useful for the detection of circulating biomarkers including circulating tumor DNA (ctDNA), microRNAs (miRNAs), proteins, and exosomes, thus improving diagnostic strategies and paving the way to personalized medicine. However, the application of liquid biopsy in oral cancer is still limited and further studies are needed to better clarify its clinical impact. The present manuscript aims to provide an updated overview of the potential use of liquid biopsy as an additional tool for the management of oral lesions by describing the available methodologies and the most promising biomarkers.

Salivary Metabolomics for Oral Cancer Detection: A Narrative Review

The development of low- or non-invasive screening tests for cancer is crucial for early detection. Saliva is an ideal biofluid containing informative components for monitoring oral and systemic diseases. Metabolomics has frequently been used to identify and quantify numerous metabolites in saliva samples, serving as novel biomarkers associated with various conditions, including cancers. This review summarizes the recent applications of salivary metabolomics in biomarker discovery in oral cancers. We discussed the prevalence, epidemiologic characteristics, and risk factors of oral cancers, as well as the currently available screening programs, in India and Japan. These data imply that the development of biomarkers by itself is inadequate in cancer detection. The use of current diagnostic methods and new technologies is necessary for efficient salivary metabolomics analysis. We also discuss the gap between biomarker discovery and nationwide screening for the early detection of oral cancer and its prevention.

Sociodemographic correlates of cervix, breast and oral cancer screening among Indian women

INTRODUCTION

Cervix, breast and oral cancers account for about one-third of all cancers in India which as a group is a major contributor to all non-communicable disease-related morbidity and mortality among women. Existing evidence suggests that early diagnosis plays a pivotal role in the prevention and intervention of these cancers, and many community-based early screening and awareness programs have been in place in developed countries. Currently, there is not enough research evidence regarding the sociodemographic correlates of cervix, breast and oral cancer screening among Indian women. In the present study, we aimed to assess the self-reported percentage and sociodemographic factors associated with the use of these three types of cancer screening services among Indian women aged 15-49 years.

METHODS

Data were collected from National Family Health Survey conducted during 2015-16. Sample population was 699,686 women aged 15-49 years. Associations between self-reported cervical, breast and oral cancer screening status and the associated sociodemographic factors were analyzed using multivariable logistic regression methods.

RESULTS

The percentage of screening for cervical (21%), breast (8.95%), and oral cancers (13.45%) varied significantly across the population sub-groups. Higher age, urban residence, higher education, having employment, health insurance, use of electronic media, higher household wealth quintile, having healthcare autonomy, showed a positive effect on taking screening services. Further analyses revealed that the strength of the associations varied considerably between urban and rural residents, denoting the need for region-specific intervention strategies. Sex of household head, age, watching TV, using radio, and having health insurance were the most significant contributors to the outcome effects.

CONCLUSIONS

The present study provides important insights regarding the current scenario of seeking cancer screening services among women in India. These findings could inform policy analysis and make an avenue for further in-depth analysis for future studies. Our findings conclude that cancer prevention policies should focus on leveraging the positive effects of better socioeconomic status, employment, health insurance ownership, exposure to electronic media, and better healthcare autonomy to improve the cancer screening service uptake among Indian women.

Attitudes and practices of tobacco cessation counseling among Saudi dental professionals: A nationwide cross-sectional survey

Background

Dental professionals can play a pivotal role in educating the public about the harmful effects of smoking and encouraging them to quit the habit.

Aim

This study assesses the attitudes and practices of tobacco cessation counseling (TCC) among dental professionals in Saudi Arabia.

Patients and Methods

This questionnaire-based cross-sectional study targeted dentists and dental interns working in government and private sectors in Saudi Arabia. We conducted a descriptive analysis by using SPSS Statistics, version 25.0.

Results

A total of 895 respondents (314 interns and 581 dentists) participated in this survey. Although the majority of respondents (93%) reported that they always ask patients about tobacco habits, only 59% reported recording tobacco habits in patients' files, and only 55% of the respondents reported explaining to patients the harmful effects of tobacco. Around 91% of the participants believe that a dental clinic is an appropriate place for TCC, and 22% believe that TCC has a negative impact on dental practice. Smoking status, work setting, and the number of years since graduation were found to be significantly associated with the respondents' attitudes and practices. Lack of training, time limitations, and lack of confidence were barriers for TCC.

Conclusions

Dental professionals in Saudi Arabia demonstrated relatively positive attitudes but weak practices of TCC. Continuous education and motivation are needed to improve dentists' confidence, attitudes, and willingness for TCC. Integration of tobacco control education in undergraduate curricula is recommended.

Update from the 5th Edition of the World Health Organization Classification of Head and Neck Tumors: Tumours of the Oral Cavity and Mobile Tongue

The fifth chapter of the upcoming fifth edition of the 2022 World Health Organization Classification of Tumours of the Head and Neck titled Tumours of the oral cavity and mobile tongue, has had some modifications from the 2017 fourth edition. A new section "Non-neoplastic Lesions", introduces two new entries: necrotizing sialometaplasia and melanoacanthoma. The combined Oral potentially malignant disorders and Oral epithelial dysplasia section in the 2015 WHO has now been separated and submucous fibrosis and HPV-associated dysplasia are also discussed in separate sections. Carcinoma cuniculatum and verrucous carcinoma are described in dedicated sections, reflecting that the oral cavity is the most common location in the head and neck for both these entities which have distinct clinical and histologic features from conventional squamous cell carcinoma. This review summarizes the changes in Chapter 5 with special reference to new additions, deletions, and sections that reflect current clinical, histological, and molecular advances.

Burden of Oral Cancer on the 10 Most Populous Countries from 1990 to 2019: Estimates from the Global Burden of Disease Study 2019

Background: Oral cancer (OC) is a common tumour that poses a threat to human health and imposes a heavy burden on countries. This study assessed the burden imposed by OC on the 10 most populous countries from 1990 to 2019 on the basis of gender, age and socio-demographic index. Methods: Data on incidence, mortality, disability-adjusted life years (DALY) and corresponding age-standardised rates (ASR) for OC in the 10 most populous countries from 1990 to 2019 were derived from the Global Burden of Disease Study 2019. Estimated annual percentage changes were calculated to assess the trends of morbidity, mortality and DALY. The indicator that served as a proxy for survival rate was the supplement of mortality-to-incidence ratio (SMIR) (1 − (M/I)). Results: The number of new cases, deaths and DALY have increased in all 10 countries in the past 30 years. Trends in age-standardised incidence rates (ASIR), age-standardised mortality rate (ASMR) and age-standardised DALY for OC in the 10 most populous countries varied. The SMIR increased in all countries, with most countries having an SMIR between 30% and 50%. In 2019, the United States had the highest SMIR at 76%, whereas Russia had the lowest at 21.7%. Incidence and mortality were close between male and female subjects in Japan, Indonesia, Mexico, India, Bangladesh and Pakistan. The incidence and mortality in male subjects in the United States, Russia, China and Brazil were two or more times those of female subjects. Gender difference was highest among patients aged 40–69 years. Conclusion: Trends and gender differences in ASIR, ASMR and age-standardised DALY for OC vary in the 10 most populous countries. Government cancer programs are often expensive to run, especially in countries with large populations. Policy makers need to take these differences into account when formulating policies.

Understanding cognitive and emotional illness representations of South Asian head and neck cancer survivors: a qualitative study

OBJECTIVES

Head and neck cancer (HNC) constitutes a substantial portion of the cancer burden worldwide, with over 550,000 new cases and over 300,000 deaths annually, with disproportionately high mortality rates in the developing countries. The large majority of HNCs are caused by tobacco use, and synergistic effects of tobacco and alcohol use. Using the Common-Sense Model (CSM) as a framework, this qualitative study sought to understand South Asian HNC survivors' cognitive and emotional representations of their cancer; and to assess if these representations differ by smokeless tobacco (SLT) vs. smoked tobacco use.

DESIGN

In-depth semi-structured interviews, conducted with South Asian HNC survivors (N = 15, 80% participants were immigrants, while 20% came to the United States for treatment) to identify key themes and issues related to HNC experience and SLT vs. smoked tobacco use.

RESULTS

The results of the study provide a deeper understanding of South Asian HNC survivor experiences with receiving a HNC diagnosis, delays in seeking treatment and related medical care, disagreement regarding smoked tobacco/SLT history as potential causes of cancer, strategies to cure the cancer or prevent recurrence, enduring physical and psycho-social consequences of treatment, and emotional impact of the cancer experience. Three key implications emerged: (a) the utility of narratives as a method of eliciting HNC survivor experience to understand patient experiences and concerns; (b) the potential for public health practitioners to harness patients' voices and the power of storytelling for developing campaigns about public awareness of SLT use, providing information and support to SLT users, and encouraging SLT quitting resources; and (c) the importance of providing clear, personalized and culturally sensitive education regarding the risks of SLT use.

CONCLUSIONS

This study underscores the significance of offering tailored tobacco cessation services to South Asian HNC survivors, and to help inform supportive models of care for others.

The health impact of smokeless tobacco products: a systematic review

INTRODUCTION

The objective was to systematically review studies on health outcomes from smokeless tobacco (SLT) products.

METHODS

We analysed published literature on the health outcomes from SLT use between 01/01/2015 to 01/02/2020, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol using PubMed, Embase, Scopus, and Google Scholar.

RESULTS

Of 53 studies included, six were global, 32 from Asia, Middle East and Africa (AMEA), nine from USA and six from Europe. 'Poor'-rated studies predominated (23;43%), in particular, for global (4;66%) and AMEA (16;50%). Health outcomes differed between SLT-products and regions; those in AMEA were associated with higher mortality (overall, cancer, Coronary heart disease (CHD), respiratory but not cardiovascular disease (CVD)), and morbidity (CVD, oral and head and neck cancers), with odds ratios up to 38.7. European studies showed no excess mortality (overall, CVD, from cancers) or morbidity (ischemic heart disease (IHD), stroke, oral, head and neck, pancreatic or colon cancers) from several meta-analyses; single studies reported elevated risk of rectal cancer and respiratory disorders. Pooled study data showed protection against developing Parkinson's disease. US studies showed mixed results for mortality (raised overall, CHD, cancer and smoking-related cancer mortality; no excess risk of respiratory or CVD mortality). Morbidity outcomes were also mixed, with some evidence of increased IHD, stroke and cancer risk (oral, head and neck). No studies reported on switching from cigarettes to SLT-products.

CONCLUSION

Our review demonstrates stark differences between different SLT-products in different regions, ranging from zero harm from European snus to greatly increased health risks in AMEA. The literature on the safety profile for SLT-products for harm reduction is incomplete and potentially misinforming policy and regulation.

Tobacco Use and Oral Health

This review outlines the important oral implications of tobacco use. The lining of the mouth (oral mucosa), if exposed to tobacco and its products in a susceptible individual, can develop benign, potentially malignant, and malignant tumours. Treatment and prognosis depend on tumour type, how early it is detected, its size and site in the oral cavity and whether it has spread. Advanced oral squamous cell carcinoma (OSCC) has a 20% 5-year survival rate. Tobacco use also increases the risk of periodontitis, peri-implantitis, caries, alveolar osteitis and halitosis. Although less life threatening than OSCC, these tobacco related conditions create a substantial financial and health burden for individuals and society. Dental practitioners routinely examine the oral cavity for signs of mucosal and tooth changes, are experienced in recognising variations from normal and have established management and referral pathways. They are also ideally positioned to provide brief interventions to assist their patients to quit smoking.

Cancer Etiology and Prevention Principle: "1 + X"

Cancer was previously thought to be an inevitable aspect of human health with no effective treatments. However, the results of in-depth cancer research suggest that most types of cancer may be preventable. Therefore, a comprehensive understanding of the disparities in cancer burden caused by different risk factors is essential to inform and improve cancer prevention and control. Here, we propose the cancer etiology and prevention principle "1 + X," where 1 denotes the primary risk factor for a cancer and X represents the secondary contributing risk factors for the cancer. We elaborate upon the "1 + X" principle with respect to risk factors for several different cancer types. The "1 + X" principle can be used for precise prevention of cancer by eliminating the main cause of a cancer and minimizing the contributing factors at the same time.