Ill-fitting dentures and oral cancer: a meta-analysis

Ill-fitting prosthesis is associated with an increased risk of elevated blood pressures

OBJECTIVE

Previous studies focused on the benefits of adequate prosthodontic treatment, while few studies have investigated the prosthodontic-related risks to health. As a modifiable oral health indicator, the association of ill-fitting prosthesis (IFP) with hypertension has not been fully explored.

METHODS

This cross-sectional study involved 158,659 adults in Beijing (2009-2017) receiving intra-oral examinations and blood pressure measurements. Logistic regression models were applied to assess the association of IFP with the prevalence of hypertension, systolic blood pressure (SBP) ≧ 140 mmHg and diastolic blood pressure (DBP) ≧ 90 mmHg, as well as subgroup analyses by different fixed IFP subgroups (according to involved teeth number) and removable IFP subgroup. We further investigated effect modifications among stratified populations.

RESULTS

158,659 individuals were included for analysis, 346 (26.86%) in IFP group and 27,380 (17.40%) in non-IFP group (p < 0.001) were hypertensive. After adjustment of sex, age, obesity, dyslipidaemia, diabetes, hsCRP, family history of CVD, self-reported smoking, self-reported drinking and WC, ORs of hypertension, SBP ≧ 140 mmHg and DBP ≧ 90 mmHg were 1.330 (95% CI: 1.162-1.522), 1.277 (95% CI: 1.098-1.486) and 1.376 (95% CI: 1.186-1.596), respectively (p < 0.05). Furthermore, after full adjustment, the number of involved teeth showed a significant incremental trend with hypertension risk in the population with and without IFP (p for trend <0.001). The IFP-blood pressure associations were more pronounced in females, 18-60 years, non-obese and diabetic participants.

CONCLUSION

As a modifiable oral indicator, IFP was significantly associated with a higher risk of hypertension.

Evaluation of nuclear morphometry in exfoliative cytology of buccal mucosa in patients with high risk of oral cancer

BACKGROUND

Oral cancer poses a significant global health burden, with India having the highest prevalence. Effective detection is crucial in effective prevention. This study aimed to evaluate nuclear morphometric parameters (NMPs) in buccal mucosa cells of smokers, correlate NMPs with dysplasia, establish cut off values for grading dysplasia, and investigate the relationship between NMPs and smoking.

METHODS

After obtaining ethical approval and informed consent, patients were recruited from the outpatient department of our institution. A target sample size of 250 was calculated. The data included smoking exposure quantified in pack-years, nuclear morphometric analysis (NMA) of buccal mucosa cells obtained through oral cytology using Image J, and the severity of dysplasia of the slides assessed by pathologists. Statistical analysis assessed the impact of dysplasia and the association between nuclear characteristics and smoking exposure. Receiver operating characteristic (ROC) plots determined the potential of these parameters to distinguish dysplasia levels.

RESULTS

Significant differences in NMPs were observed among different smoking groups. Dysplasia severity had a significant correlation with NMPs, and strong correlations were found between NMPs and lifetime smoking exposure. ROC analysis established cut off values for NMPs with good sensitivity and specificity for classifying dysplasia severity.

CONCLUSIONS

This study highlights the potential of NMA as a tool for oral cancer screening. NMPs can distinguish dysplasia severity and correlate with tobacco (smoking). The efficiency of NMA in a non-invasive oral cytology offers promise for patient-centered screening Additionally, the findings suggest future applications in telepathology and the potential for AI integration in automated screening after conducting multicentric large-scale studies.

Global epidemiologic patterns of oropharyngeal cancer incidence trends

BACKGROUND

The emergence of human papillomavirus (HPV)-positive oropharyngeal cancer and evolving tobacco use patterns have changed the landscape of head and neck cancer epidemiology internationally. We investigated updated trends in oropharyngeal cancer incidence worldwide.

METHODS

We analyzed cancer incidence data between 1993 and 2012 from 42 countries using the Cancer Incidence in Five Continents database volumes V through XI. Trends in oropharyngeal cancer incidence were compared with oral cavity cancers and lung squamous cell carcinomas using log-linear regression and age period-cohort modeling.

RESULTS

In total, 156 567 oropharyngeal cancer, 146 693 oral cavity cancer, and 621 947 lung squamous cell carcinoma patients were included. Oropharyngeal cancer incidence increased (P < .05) in 19 and 23 countries in men and women, respectively. In countries with increasing male oropharyngeal cancer incidence, all but 1 had statistically significant decreases in lung squamous cell carcinoma incidence, and all but 2 had decreasing or nonsignificant net drifts for oral cavity cancer. Increased oropharyngeal cancer incidence was observed both in middle-aged (40-59 years) and older (≥60 years) male cohorts, with strong nonlinear birth cohort effects. In 20 countries where oropharyngeal cancer incidence increased for women and age period-cohort analysis was possible, 13 had negative or nonsignificant lung squamous cell carcinoma net drifts, including 4 countries with higher oropharyngeal cancer net drifts vs both lung squamous cell carcinoma and oral cavity cancer (P < .05 for all comparisons).

CONCLUSIONS

Increasing oropharyngeal cancer incidence is seen among an expanding array of countries worldwide. In men, increased oropharyngeal cancer is extending to older age groups, likely driven by human papillomavirus-related birth cohort effects. In women, more diverse patterns were observed, suggesting a complex interplay of risks factors varying by country, including several countries where female oropharyngeal cancer increases may be driven by HPV.

Neighborhood socioeconomic status and race are associated with incidence disparities in oral cavity cancers

OBJECTIVES

To determine the association between neighborhood socioeconomic status (nSES), race and incidence rate trends of oral cavity cancer (OCC).

MATERIALS AND METHODS

We used data from the SEER (Surveillance, Epidemiology, and End Results) 18 Census Tract-level SES and Rurality Database (2006-2018) database of the National Cancer Institute to create cohorts of OCC patients between 2006 and 2018. Annual incidence rates were calculated and trends in rates were estimated using joinpoints regression.

RESULTS

The incidence of OCC is the highest among low nSES White Americans (2.86 per 100 000 persons) and the lowest among high nSES Black Americans (1.17 per 100 000 persons). Incidence has significantly increased among Asian Americans (annual percent change [APC]: low nSES-2.4, high nSES-2.6) and White Americans (APC: low nSES-1.4, high nSES-1.6). Significant increases in the incidence of oral tongue cancer in these groups primarily drive this increase. Other increases were noted in alveolar ridge cancer among White Americans and hard palate cancer among Asian Americans. OCC incidence decreased significantly in Hispanic Americans of high nSES (APC: -2.5) and Black Americans of low nSES (APC: -2.7). Floor of mouth cancer incidence decreased among most groups.

CONCLUSION

Despite the overall decreasing incidence of OCC, these trends are inconsistent among all OCC subsites. Differences are seen by race, nSES, and subsite, indicating intersectional barriers that extend beyond nSES and race and ethnicity alone. Further research on risk factors and developing interventions targeting vulnerable groups is needed.

Oral Cavity Squamous Cell Carcinoma Risk Factors: State of the Art

Head and neck (HN) squamous cell carcinomas (SCCs) originate from the epithelial cells of the mucosal linings of the upper aerodigestive tract, which includes the oral cavity, the pharynx, the larynx, and the sinonasal cavities. There are many associated risk factors, including alcohol drinking coupled with tobacco use, which accounts for 70% to 80% of HNSCCs. Human papilloma virus (HPV) is another independent risk factor for oropharyngeal SCC, but it is only a minor contributor to oral cavity SCC (OSCC). Betel quid chewing is also an established risk factor in southeast Asian countries. However, OSCC, and especially oral tongue cancer, incidence has been reported to be increasing in several countries, suggesting risk factors that have not been identified yet. This review summarizes the established risk factors for oral cavity squamous cell carcinomas and examines other undemonstrated risk factors for HNSCC.

Evolution of the Incidence of Oral Cavity Cancers in the Elderly from 1990 to 2018

OBJECTIVES

To describe the evolution of the incidence of oral cavity cancers (OCC) among elderly patients in France between 1990 and 2018 and to compare it to the incidence of other cancers sharing the same main risk factors.

MATERIAL AND METHODS

The incidence of cancers in mainland France from 1990 to 2018 was estimated from incidence data observed in every cancer registry of the Francim network. Incidence was modeled by a 2-dimensional penalized spline of age and year of diagnosis, associated with a random effect corresponding to the registry. The elderly population was divided into two groups: 70-79 years old and ≥80 years old.

RESULTS

There was a 72% increase in the number of OCC cases in women over 70 years of age between the periods 1990-1999 and 2010-2018. As for men, there was a stabilization in the number of cases (+2%). Over the same period, for laryngeal and hypopharyngeal cancers, there was a decrease in incidence in elderly men and an increase in elderly women, although less marked than for OCC.

CONCLUSIONS

Since the 1990s, the incidence of OCC has been increasing in elderly subjects in France, particularly in women. Population aging and growth or alcohol and tobacco consumption alone do not seem to explain this increase, which is not observed in the same proportions for other upper aerodigestive tract cancer subsites sharing the same main risk factors.

Dental Care for Older Adults

There is a global increase in the older population. Unfortunately, dental conditions in the older population can sometimes be poor as a result of worsened physical conditions and the cumulative damage caused by dental diseases in the past. Many suffer from oral diseases such as dental caries and periodontal disease but receive no regular dental care. Oral conditions and systemic problems are interrelated. Chronic medical problems and polypharmacy are common among them. These conditions may lead to xerostomia with or without a decrease in saliva output. Additionally, many older adults have deteriorated masticatory function associated with physical health issues such as frailty. Preventive measures are crucial to stop oral diseases from progressing and the replacement of missing teeth is needed when masticatory function is impaired. Older adults also suffer a higher risk of oral cancer because of their less resilient but more permeable oral mucosa. With the increasing need for elderly dental care, dentists should equip themselves with knowledge and skills in geriatric dentistry. They should help older adults to develop and maintain the functional ability that enables well-being in older age. This communication article aims to discuss the relevant medical conditions, common dental diseases, and dental care for older adults.

Chronic mechanical trauma/irritation and oral carcinoma: A systematic review showing low evidence to support an association

BACKGROUND

Chronic trauma of oral mucosa, resulting from repeated and persistent mechanical irritative action of an intraoral injury agent, has repeatedly been reported to be possibly implicated in the development of oral squamous cell carcinoma (OSCC).

OBJECTIVES

The present systematic review aimed to assess whether chronic mechanical trauma can be considered a risk factor for OSCC.

DATA SOURCES

PubMed, CENTRAL (Cochrane Central Register of Controlled Trials), Scopus; EMBASE, Web of Science.

STUDY ELIGIBILITY CRITERIA

Cohort studies comparing OSCC incidence among subjects with/without chronic mechanical trauma or case-control or cross-sectional studies comparing chronic mechanical trauma among subjects with/without OSCC.

RESULTS

Only one prospective case-control study fulfilled the inclusion criteria, but the quality of the evidence provided is not enough to define trauma as a risk factor for OSCC. The main limitation is the presence of only one case-control study at high risk of bias. In the absence of strong evidence supporting the role of trauma in OSCC, a thorough discussion on trauma and carcinogenesis has been performed.

CONCLUSIONS

Available evidence does not support an active role for chronic trauma in oral carcinogenesis, neither as promoter nor as progressor factor. Prospective cohort studies able to better assess trauma in OSCC are needed.

Chronic mechanical irritation enhances the effect of tobacco and alcohol on the risk of oral squamous cell carcinoma: a case-control study in Argentina

OBJECTIVES

Oral squamous cell carcinoma (OSCC) is a multifactorial disease. The individual effect of each risk factor for OSCC may be conditioned by the frequency of other factors. The objective of this study was to identify the association between chronic mechanical irritation (CMI) and OSCC and to analyse the influence of CMI on other important risk factors for OSCC.

MATERIALS AND METHODS

A prospective and age/sex-matched case-control study was performed in two institutions from Argentina between 2009 and 2019, with consecutive and newly diagnosed OSCC. The frequencies of tobacco, alcohol, and CMI were analysed using conditional logistic regression. Cumulative tobacco consumption and the presence of CMI were analysed using the Mann-Whitney test.

RESULTS

CMI and OSCC were associated with an OR of 7.02 (95% CI 3.57-13.78, p < 0.001). The combination of CMI and alcohol demonstrated the highest risk of OSCC (OR 53.83, CI 95% 8.04-360, p < 0.0001), followed by the combination of CMI, tobacco, and alcohol (OR 48.06, CI 95% 8.47-272, p < 0.0001). The combination of CMI and tobacco was also significant (OR 5.61, CI 95% 1.07-29.54, p = 0.042). Patients with CMI developed OSCC with less cumulative tobacco use compared with those without CMI.

CONCLUSION

CMI is an independent risk factor for OSCC, and it could act as a risk modifier among tobacco and alcohol users having an enhancing effect.

CLINICAL RELEVANCE

Elimination of CMI could decrease the risk of OSCC.

Dental management before radiotherapy of the head and neck region: 4-year single-center experience

OBJECTIVE

To review our experience with a standardized dental management approach in patients with planned radiotherapy of the head and neck region based on preradiation and follow-up data.

MATERIAL AND METHODS

Records of patients who underwent radiotherapy between June 2016 and November 2020 were reviewed. Data on dental findings and therapeutic recommendations were extracted from a prospectively managed database. Hospital records were used to obtain follow-up data.

RESULTS

Two hundred eighty-one patient records were identified. After the exclusion of 81 patients because of incomplete data, 200 patients were included in the study. Dental findings relevant to radiotherapy were found in 144 cases (72.0%). Teeth extractions were recommended in 112 (56.0%) patients. Follow-up data were available for 172 (86.0%) patients (mean follow-up: 16.8 ± 10.7 months). Radiodermatitis was the most frequently observed sequela of radiotherapy (42.4%), followed by dysphagia (38.4%) and stomatitis (36.6%). Osteoradionecrosis was observed in only 2.3% of the patients.

CONCLUSION

Dental findings relevant to planned radiotherapy were frequent and in many cases resulted in recommendations for teeth extraction. Based on our standardized dental management protocol, we observed low rates of late oral complications after radiotherapy of the head and neck region.

Diverging incidence trends of oral tongue cancer compared to other head and neck cancers in young adults in France

While head and neck cancer incidence decreased worldwide due to reduced tobacco and alcohol consumption, oral tongue cancer (OTC) incidence has been reported to be increasing in several countries. Our study examines the incidence trends of OTC in France from 1990 to 2018, globally and by age; and compares the incidence trends with the evolution of the incidence of other human papilloma virus-unrelated head and neck squamous cell carcinoma, that is, cancers of the remaining subsites of the oral cavity (RSOCC) and laryngeal cancers for the period 1990 to 2018. World age-standardized incidence rates of oral tongue cancers (C02), cancers of the remaining subsites of the oral cavity (RSOCC, C03-06) and laryngeal cancers (C32) were estimated using the French National Network of Cancer Registries for the period 1990 to 2018. Trends in national incidence rates were estimated from a mixed-effect Poisson model including age and year effects using penalized splines and a district-random effect. In women aged 30 and 40, a significant increase in OTC incidence was observed, while ROSCC showed a nonsignificant incidence decrease. In young men aged 25, a marginally significant increase of OTC incidence years was observed, while incidence rates of RSOCC significantly declined. The results suggest a tendency towards diverging incidence trends for OTC compared to RSOCC and laryngeal cancer in young adults. The observed trends may reflect changes in underlying exposures or emerging exposures not yet identified, and stress the need to further investigate the etiology of oral tongue cancers.

Denture induced mechanotransduction can contribute to oral carcinogenesis

Mechanical stresses in the form of substrate rigidity, hydrostatic pressure, compressive, tensile and shear stress has been regarded as an important motive for the epithelial carcinogenesis brought about by the activation of Hippo signaling pathways. Masticatory forces generated in edentulous patients with dentures are transferred directly to the palatal mucosa (maxillary denture) and alveolar mucosa (mandibular denture). Thus, the oral mucosa present underneath the dentures experiences compressive, shear and tensile stresses on a day-to-day basis. These stresses can induce carcinogenesis by mechano-transduction and subsequent activation of numerous carcinogenesis relevant signaling pathways such as the HIPPO pathway. With this contention in mind, we proposed a hypothesis, which explains the pathogenesis for the presence of oral squamous cell carcinoma in denture wearer patients. Efforts were made to envisage the appropriate experimentations for the evaluation of the hypothesis. As a therapeutic implication, flexible dentures, soft denture, or medicated dentures could be prescribed for the high-risk groups having potentially malignant lesions in the oral cavity.

Quality of information about oral cancer in Brazilian Portuguese available on Google, Youtube, and Instagram

Background

To evaluate the quality of oral cancer information in Brazilian Portuguese on Google, YouTube, and Instagram.

Material and Methods

The first 100 links of each platform characterized the initial sample. The websites and Instagram were evaluated using the JAMA benchmarks, the Discern instrument, and the Flesch readability index (Flesch Reading Ease). The existence of Health on the Net (HON) code was also registered on websites. The usefulness of each video on YouTube was classified as not useful, slightly useful, moderately useful, or very useful.

Results

Thirty-four websites, 39 Instagram posts, and 57 videos were evaluated, of which 18 (33.3%) websites and 19 (48.7%) Instagram posts covered only 2 of the 4 JAMA benchmarks. For the Discern instrument, 20 (37%) and 18 (33.3%) websites exhibited low and moderate reliability, respectively, while 26 (66.7%) Instagram posts were of low confidence. The level of intelligibility of both websites and Instagram was difficult. Only three websites exhibited the HONcode. Forty-one (71.9%) videos on YouTube were moderately useful.

Conclusions

Information on oral cancer on the Internet in Brazilian Portuguese is of low quality. Thus, educational and governmental institutions have a responsibility to produce and indicate reliable sources of information for the population.

Key words:Access to information, internet, oral cancer.

Evaluation of Cadmium Levels in Dental Calculus of Male Oral SCC Patients with Betel-Quid Chewing in Hunan Province of China

Cadmium (Cd) is a widespread trace toxic heavy metal with long biological half-life and may induce higher risk of cancer on multiple organs of human body. Recent studies have confirmed that dental calculus has enormous potential for investigation of exposure to Cd in the human mouth by acting as a time capsule. We aimed to examine relationship between Cd levels in dental calculus due to betel-quid chewing and risk of oral cancer. This study included 85 male oral squamous cell carcinoma (SCC) cases with betel-quid chewing and smoking as observation subjects (group A) and 67 healthy people with smoking but without betel-quid chewing as control subjects (group B) in Hunan province of Mainland China. Cd levels in calcified dental calculus samples from all participants were measured by inductively coupled plasma mass spectrometry (ICP-MS). The results of this study indicated that cadmium levels in dental calculus were significantly higher in male oral SCC patients with betel-quid chewing and smoking than that in healthy individuals without habit of betel-quid chewing and with smoking (p < 0.0001). This study gives some evidence to support that there may be a positive relationship between cadmium in dental calculus due to betel-quid chewing and risk of oral SCC.

Assessment of the cancerization risk for oral potentially malignant disorders by clinical risk model combined with autofluorescence and brush biopsy with DNA-image cytometry

PURPOSE

To explore the feasibility of assessing the cancerization risk of oral potentially malignant disorders (OPMD) through a clinical risk model combined with autofluorescence and brush biopsy with DNA-image cytometry.

METHODS

We collected the baseline clinical data of 269 patients; then, performed autofluorescence, brush biopsy with DNA-image cytometry and histopathological examination. Then, we obtained the significant factors by univariate logistic analysis, constructed the clinical risk model by multiple logistic regression and selected the optimal cutoff value according to the maximum Youden index. Finally, we calculated the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the clinical risk score ≥ cutoff value, autofluorescence and brush biopsy with DNA-image cytometry, and plotted the receiver-operating characteristic (ROC) curves and decision curve analysis (DCA).

RESULTS

The clinical risk model is represented by the formula: 1 × gender + 1.6 × age group + 1 × lesion site + 1.4 × local stimulus + 1.5 × drink. The area under the curve (AUC) was 0.83, and the optimal cutoff score was 3. The AUC indicated that the clinical risk score ≥ 3 (0.74) and autofluorescence (0.77) had a certain diagnostic values, while brush biopsy with DNA-image cytometry (0.92) displayed a good value. Besides, the DCA showed that all three tests had clinical significance.

CONCLUSIONS

The cancerization risk of patients can be assessed by the clinical risk model combined with sequence application of autofluorescence and brush biopsy with DNA-image cytometry, to decide whether histopathological examination or other intervention measures should be selected.

Oral health of older people: tracking soft tissue injuries for the prevention of oral cancer

OBJECTIVE

To detect oral soft tissue injuries in older people.

METHOD

A quantitative analytical cross-sectional study conducted in Fortaleza, Ceará. Individual interviews addressed age, gender, marital status, income, and education. The community oral health indicator was used to detect oral soft tissue injuries and their location.

RESULTS

Most of the 821 participants aged 60-100 years were women (580; 70.6%), attended school for up to 5 years (401; 48.8%), were illiterate (201; 24.5%), were retired (608; 74.1%), and received up to 2 wages (701; 85.4%). A total of 604 participants (73.6%) wore dentures. Injuries included red patches (152; 55.9%), blisters (58; 21.3%), lesions and/or wounds (39; 14.3%), and white patches (30; 11%). Locations of injuries were the roof of the mouth (167; 61.4%), gums (62; 22.8%), cheeks (39; 14.3%), tongue (15; 5.5%), lips (15; 5.5%), and the floor of the mouth (12; 4.4%). Injuries were associated with age (p<0.001), retirement (p=0.005), education (p=0.010), dentures (p<0.001) and red patches (p<0.001).

CONCLUSION

Tracking soft tissue injuries and referring older adults with suspected malignant lesions to the health team should be included as oral cancer identification and prevention measures. Furthermore, health care providers should raise older adults' awareness of the importance of regular preventive examinations.

Prevalence of Oral Premalignant Lesions and Its Risk Factors among the Adult Population in Udupi Taluk of Coastal Karnataka, India

Objective:

Globally oral cancer is one of the ten most common cancers with prevalence being high in Central and South East Asian countries. This survey was conducted to estimate the prevalence of oral pre-malignant lesions (OPML) and to identify their risk factors.

Methods:

A community based cross-sectional study was carried out among 2033 individuals aged ≥18 years. A questionnaire was administered to collect socio-demographic characteristics, various risk factors for oral cancer and presence of its symptoms. Oral cavity of all the participants was examined in detail by the study investigator as per WHO guidelines for the early diagnosis of oral neoplasia.

Result:

The prevalence of OPML was found to be 3.73%. Among those with OPML, all were ever tobacco consumers and had poor oral hygiene. A significant association was observed between OPML and younger age group (OR=2.56, 95% CI 1.08-6.02), males (OR=26.76, 95% CI 8.40-85.19) and low socio-economic status (OR = 1.91, 95% CI 1.20-3.02). Tobacco (p<0.001), alcohol (OR= 7.92, 95% CI 4.77-13.14) and areca nut consumption (OR = 5.48, 95% CI 3.42-8.77) were strongly associated with OPML. On multivariate analysis among ever tobacco users, OPML was associated with younger individuals, males and those using smokeless forms of tobacco (p <0.05). The study showed that the participants with OPML were more likely to be never married (OR=1.6, 95% CI 0.92-2.96), to be unskilled workers (OR= 1.45, 95% CI 0.61-3.43), to have suffered from oral trauma (OR =1.30, 95% CI 0.75-2.26), to have consumed hot and spicy food frequently (OR=1.53, 95% CI 0.96-2.24), to have consumed fruits infrequently (OR=1.53, 95% CI 0.90-2.59) and to report family history of any cancer (OR = 1.29, 95% CI 0.58-2.87). However, these associations were statistically insignificant.

Conclusion:

The study reinforces that use of substances such as tobacco, alcohol and areca nut are the modifiable risk factors for OPML.

Evidence for chronic mechanical irritation as a causative factor in oral cancer: application of Bradford Hill criteria

Chronic mechanical irritation (CMI) of the oral mucosa has been proposed as a risk factor for oral cancer (OC), but the available evidence is limited and controversial. One of the main limitations is the lack of proper criteria to define and classify CMI. The objective of this narrative review is to apply the Bradford Hill causality criteria to assess such an association based on the published literature. The level of evidence is not conclusive, mainly due to methodological shortcomings. Hence, to systematize future CMI research, we recommend the following items should be included: a clear definition for CMI, ascertaining any temporal association, recording all types of CMI: dental, prosthetic, and functional. Finally, it is important to emphasize that studies dealing with risk factors for OC should not only be restricted to established factors such as tobacco, alcohol, and areca nut consumption but should also consider other factors including the patient’s dental condition. In this regard, CMI, tooth loss, periodontal disease, and many others could be included. The causality criteria set out by Bradford Hill could be used for studying different controversial risk factors for OC.

Squamous cell carcinoma in the anophthalmic socket: a series of four cases with HPV-16 profiling

PURPOSE

To present the clinical and histological features of squamous cell carcinoma (SCC) in the anophthalmic socket in four adult patients, and to determine the presence of human papillomavirus infection (HPV).

METHODS

Retrospective case series of four adult patients with SCC of the anophthalmic socket. P16 immunohistochemistry and HPV testing was carried out in all cases. The authors report clinical findings, histopathology, management and outcomes for all four patients with conjunctival SCC. Previously reported cases of conjunctival SCC in anophthalmic sockets were reviewed.

RESULTS

Four adult patients presented with eyelid lumps, discharge or change in prosthesis fit. Common examination findings included papillomatous changes, eyelid masses and epithelial changes. Three out of the four cases (75%) were positive for p16 by immunohistochemistry and the same cases positive for HPV-16 DNA. All patients received cryotherapy, topical or intralesional chemotherapy. Two patients proceeded to exenteration for control of invasive disease.

CONCLUSIONS

To the authors' knowledge, this is the largest series of SCC in the anophthalmic socket with comprehensive annotation of HPV status. Although socket conjunctiva is protected from environmental radiation, there is still a risk of neoplastic transformation in this tissue, thus patient education and regular checking of sockets by ophthalmologists should be undertaken as a preventative measure. The potential role of HPV in these tumours warrants further investigation.

Oral cancer associated with chronic mechanical irritation of the oral mucosa

Background

Most of the studies dealing with Chronic Mechanical Irritation (CMI) and Oral Cancer (OC) only considered prosthetic and dental variables separately, and CMI functional factors are not registered. Thus, the aim of this study was to assess OC risk in individuals with dental, prosthetic and functional CMI. Also, we examined CMI presence in relation to tumor size.

Material and Methods

A case-control study was carried out from 2009 to 2013. Study group were squamous cell carcinoma cases; control group was patients seeking dental treatment in the same institution.

Results

153 patients were studied (Study group n=53, Control group n=100). CMI reproducibility displayed a correlation coefficient of 1 (p<0.0001). Bivariate analysis showed statistically significant associations for all variables (age, gender, tobacco and alcohol consumption and CMI). Multivariate analysis exhibited statistical significance for age, alcohol, and CMI, but not for gender or tobacco. Relationship of CMI with tumor size showed no statistically significant differences.

Conclusions

CMI could be regarded as a risk factor for oral cancer. In individuals with other OC risk factors, proper treatment of the mechanical injuring factors (dental, prosthetic and functional) could be an important measure to reduce the risk of oral cancer.

Key words:Oral cancer, risk factors, chronic mechanical irritation, tumor size, case-control study.

Characterization of Chronic Mechanical Irritation in Oral Cancer

Objective. Oral mucosa could host many lesions originated by chronic mechanical irritation (CMI) from teeth or dentures, and it has been proposed as risk factor for oral cancer. Nevertheless, the features of CMI factors in oral cancer and other lesions are not assessed. The aim of this study is to describe CMI features regarding type (dental, prosthetic, and/or functional), localization, and time span. Materials and Methods. Three groups were studied in this cross-sectional study: Oral Cancer (OC); Chronic Traumatic Ulcer (CTU); and Benign Irritative Mechanical Lesions (BIML). All sources of mechanical irritation were included: dental, prosthetic, and functional. Results. 285 patients (176 females, 109 males) were studied: OC = 38, CTU = 44, and BIML = 203. The most frequent CMI factor was dental, followed by functional and prosthetic in all groups; 76.5% (n = 218) presented functional factors. Buccal mucosa (45%) and tongue (42%) were the most affected sites. Time of action of CMI displayed statistically significant differences between BIML, CTU, and OC groups, with a mean of 21, 33, and 49 months, respectively. Conclusions. CMI should be properly recorded with as much detail as alcohol and tobacco consumption. CMI associated lesions are produced by dental or prosthetic factors, usually in relation to functional factors, involving mainly tongue and buccal mucosa.

The Role of Chronic Mucosal Trauma in Oral Cancer: A Review of Literature

Chronic mucosal trauma resulting from sharp teeth, dentures, faulty restoration, or implants has frequently been associated with the development of oral cancer. The definitive evidence for the same is lacking. We undertook a search using the terms – dental trauma, mucosal trauma, oral cancer, squamous cell carcinoma, risk factor, potentially malignant lesion, dental factor, mechanical irritation, dental irritation, and cancer in the following electronic databases: MEDLINE, PubMed, ScienceDirect, Cochrane Database of Systematic Reviews, and Wiley InterScience. The search yielded 788 articles. Of these articles, only 22 articles described chronic mucosal trauma as risk factors for oral cancers and were considered in this review. The review shows that chronic mucosal irritation resulting from ill-fitting dentures may be considered a risk factor for the development of oral cancer, such cancers occur commonly over the lateral border of the tongue. However, no association has been proven between the duration of denture use and cancer formation. In patients without any addiction, such cancers occur more frequently in females. These cancers may present with an early nodal disease but their prognosis and outcomes have not been studied separately till now.

Influence of oral hygiene and its interaction with standard of education on the risk of oral cancer in women who neither smoked nor drank alcohol: a hospital-based, case-control study

We know of only limited data about the role of oral hygiene and the risk of oral cancer with different standards of education. The aim of this study was to assess the association between oral hygiene and risk of oral cancer, with stratification by standard of education, in Chinese women. We organised a case-control study with 250 women with oral cancer and 996 age-matched controls in Fujian, China. Data were collected by personal interview using a structured questionnaire. We used unconditional logistic regression with stratification by educational standard to estimate the odds ratios (OR) and 95% CI. Tooth-brushing twice a day or more was inversely related to the risk of oral cancer in women with high school education or above (OR 0.50; 95% CI 0.25 to 0.98), but not in those who were illiterate or had primary-middle school education. Wearing dentures showed an increased risk only in less well-educated women: the OR were 2.23 (95% CI 1.14 to 4.34) for the illiterate and 1.68 (95% CI 1.08 to 2.62) for the primary-middle school group. The loss of more than five teeth and oral ulceration were associated with increased risks of oral cancer in all three groups. There was also a multiplicative interaction between oral hygiene and standard of education for risk of oral cancer (p=0.001). Our results suggest that oral hygiene seems to have a critical role in the risk of oral cancer in Chinese women, but this effect may be modified by their educational standard.

The role of oral hygiene in head and neck cancer: results from International Head and Neck Cancer Epidemiology (INHANCE) consortium

BACKGROUND

Poor oral hygiene has been proposed to contribute to head and neck cancer (HNC) risk, although causality and independency of some indicators are uncertain. This study investigates the relationship of five oral hygiene indicators with incident HNCs.

METHODS

In a pooled analysis of 8925 HNC cases and 12 527 controls from 13 studies participating in the International Head and Neck Cancer Epidemiology Consortium, comparable data on good oral hygiene indicators were harmonized. These included: no denture wear, no gum disease (or bleeding), <5 missing teeth, tooth brushing at least daily, and visiting a dentist ≥once a year. Logistic regression was used to estimate the effects of each oral hygiene indicator and cumulative score on HNC risk, adjusting for tobacco smoking and alcohol consumption.

RESULTS

Inverse associations with any HNC, in the hypothesized direction, were observed for <5 missing teeth [odds ratio (OR) = 0.78; 95% confidence interval (CI) 0.74, 0.82], annual dentist visit (OR = 0.82; 95% CI 0.78, 0.87), daily tooth brushing (OR = 0.83, 95% CI 0.79, 0.88), and no gum disease (OR = 0.94; 95% CI 0.89, 0.99), and no association was observed for wearing dentures. These associations were relatively consistent across specific cancer sites, especially for tooth brushing and dentist visits. The population attributable fraction for ≤ 2 out of 5 good oral hygiene indicators was 8.9% (95% CI 3.3%, 14%) for oral cavity cancer.

CONCLUSION

Good oral hygiene, as characterized by few missing teeth, annual dentist visits, and daily tooth brushing, may modestly reduce the risk of HNC.

Pretreatment oral hygiene habits and survival of head and neck squamous cell carcinoma (HNSCC) patients

Background

The survival time of patients with head and neck squamous cell carcinoma (HNSCC) is related to health behavior, such as tobacco smoking and alcohol consumption. Poor oral health (OH), dental care (DC) and the frequent use of mouthwash have been shown to represent independent risk factors for head and neck cancerogenesis, but their impact on the survival of HNSCC patients has not been systematically investigated.

Methods

Two hundred seventy-six incident HNSCC cases recruited for the ARCAGE study were followed through a period of 6–10 years. Interview-based information on wearing of dentures, gum bleeding, teeth brushing, use of floss and dentist visits were grouped into weighted composite scores, i.e. oral health (OH) and dental care (DH). Use of mouthwash was assessed as frequency per day. Also obtained were other types of health behavior, such as smoking, alcohol drinking and diet, appreciated as both confounding and study variables. Endpoints were progression-free survival, overall survival and tumor-specific survival. Prognostic values were estimated using Kaplan-Meier analysis and Cox proportional hazards regression models.

Results

A good dental care score, summarizing annual dental visits, daily teeth cleaning and use of floss was associated with longer overall survival time (p = .001). The results of the Cox regression models similarly suggested a higher risk of tumor progression and shortened overall survival in patients with poor dental care, but the results lost their statistical significance after other types of health behavior had been controlled for. Frequent use of mouthwash (≥ 2 times/day) significantly increased the risk of tumor-specific death (HR = 2.26; CI = 1.19–4.32). Alcohol consumption and tobacco smoking were dose-dependently associated with tumor progression and shorter overall survival.

Conclusion

Frequent mouthwash use of ≥ 2 times/day seems to elevate the risk of tumor-specific death in HNSCC patients. Good dental care scores are associated with longer overall survival.

Electronic supplementary material

The online version of this article (doi:10.1186/s12903-016-0185-0) contains supplementary material, which is available to authorized users.