Derivation and validation of a risk-factor model for detection of oral potentially malignant disorders in populations with high prevalence

Evaluation of salivary MMP-9 in oral squamous cell carcinoma and oral leukoplakia using ELISA

Background

Cancer of the lip and the oral cavity is collectively the sixth most common malignancy worldwide, out of which 90% are oral squamous cell carcinomas (OSCCs). Oral cancer survival rates depend mainly upon the stage in which it is diagnosed. Successful early detection would eventually increase the survival rate. OSCCs may be preceded by potentially malignant disorders (PMDs) that are characterised by visible clinical changes in the oral mucosa. Correct diagnosis and timely treatment of PMDs may help prevent malignant transformation in oral lesions. Oral leukoplakia (OL) is the best known potentially malignant disorder of the oral mucosa with a malignant transformation rate of about 3% to 33%. Tumour markers in saliva have emerged as a new diagnostic tool in the early detection of oral cancer. Matrix metalloproteinase 9 (MMP-9) is a gelatinase which plays an important role in tumourogenisis. The present study was done to evaluate the salivary levels of MMP-9 in OSCC and oral leukoplakia patients using enzyme-linked immunosorbent assay (ELISA).

Materials and Methods

The study was conducted among 102 subjects, which included 34 OSCC patients (group I), 34 OL patients (group II), and 34 healthy subjects (group III). Unstimulated saliva was collected by the passive drooling method from all the study subjects during the study period, centrifuged, and stored at -80°C. The salivary MMP-9 was estimated in mg/ml using the sandwich ELISA technique. The data were analysed using a statistical software package, EZR. One-way analysis of variance was used for the comparison of salivary MMP-9 levels in OSCC, OL, and normal oral mucosa. Scheffe's multiple comparison was carried out to compare salivary MMP-9 levels among the different histological grades of OSCC and oral epithelial dysplasia. For all statistical interpretations, P ≤ 0.0 was considered the threshold for statistical significance.

Results and Conclusion

The mean salivary MMP-9 level in OSCC, OL, and normal oral mucosa was 50.9 ± 5.7 ng/ml, 31.6 ± 6 ng/ml, and 16.2 ± 4.8 ng/ml, respectively. Patients with OSCC had significantly higher levels of salivary MMP-9 when compared to OL and normal mucosa. Higher levels of salivary MMP-9 were observed in poorly differentiated OSCC when compared to well and moderately differentiated OSCCs. The salivary MMP-9 was higher in severe oral epithelial dysplasia when compared to mild and moderate oral epithelial dysplasias. As malignant transformation rates are higher in patients with severe oral epithelial dysplasia when compared to mild and moderate oral epithelial dysplasia, salivary MMP-9 could be considered as a surrogate marker of malignant transformation.

Explainable ensemble learning model improves identification of candidates for oral cancer screening

OBJECTIVES

Artificial intelligence could enhance the use of disparate risk factors (crude method) for better stratification of patients to be screened for oral cancer. This study aims to construct a meta-classifier that considers diverse risk factors to identify patients at risk of oral cancer and other suspicious oral diseases for targeted screening.

MATERIALS AND METHODS

A retrospective dataset from a community oral cancer screening program was used to construct and train the novel voting meta-classifier. Comprehensive risk factor information from this dataset was used as input features for eleven supervised learning algorithms which served as base learners and provided predicted probabilities that are weighted and aggregated by the meta-classifier. Training dataset was augmented using SMOTE-ENN. Additionally, Shapley additive explanations (SHAP) values were generated to implement the explainability of the model and display the important risk factors.

RESULTS

Our meta-classifier had an internal validation recall, specificity, and AUROC of 0.83, 0.86, and 0.85 for identifying the risk of oral cancer and 0.92, 0.60, and 0.76 for identifying suspicious oral mucosal disease respectively. Upon external validation, the meta-classifier had a significantly higher AUROC than the crude/current method used for identifying the risk of oral cancer (0.78 vs 0.46; p = 0.001) Also, the meta-classifier had better recall than the crude method for predicting the risk of suspicious oral mucosal diseases (0.78 vs 0.47).

CONCLUSION

Overall, these findings showcase that our approach optimizes the use of risk factors in identifying patients for oral screening which suggests potential clinical application.

Risk prediction models for head and neck cancer: A rapid review

Background

Cancer risk assessment models are used to support prevention and early detection. However, few models have been developed for head and neck cancer (HNC).

Methods

A rapid review of Embase and MEDLINE identified n = 3045 articles. Following dual screening, n = 14 studies were included. Quality appraisal using the PROBAST (risk of bias) instrument was conducted, and a narrative synthesis was performed to identify the best performing models in terms of risk factors and designs.

Results

Six of the 14 models were assessed as "high" quality. Of these, three had high predictive performance achieving area under curve values over 0.8 (0.87-0.89). The common features of these models were their inclusion of predictors carefully tailored to the target population/anatomical subsite and development with external validation.

Conclusions

Some existing models do possess the potential to identify and stratify those at risk of HNC but there is scope for improvement.

Performance of a simplified scoring system for risk stratification in oral cancer and oral potentially malignant disorders screening

BACKGROUND

Impact and efficiency of oral cancer and oral potentially malignant disorders screening are most realized in "at-risk" individuals. However, tools that can provide essential knowledge on individuals' risks are not applied in risk-based screening. This study aims to optimize a simplified risk scoring system for risk stratification in organized oral cancer and oral potentially malignant disorders screening.

METHODS

Participants were invited to attend a community-based oral cancer and oral potentially malignant disorders screening program in Hong Kong. Visual oral examination was performed for all attendees and information on sociodemographic characteristics as well as habitual, lifestyle, familial, and comorbidity risk factors were obtained. Individuals' status of those found to have suspicious lesions following biopsy and histopathology were classified as positive/negative and this outcome was used in a multiple logistic regression analysis with variables collected during screening. Odds ratio weightings were then used to develop a simplified risk scoring system which was validated in an external cohort.

RESULTS

Of 979 participants, 4.5% had positive status following confirmatory diagnosis. A 12-variable simplified risk scoring system with weightings was generated with an AUC, sensitivity, and specificity of 0.82, 0.71, and 0.78 for delineating high-risk cases. Further optimization on the validation cohort of 491 participants yielded a sensitivity and specificity of 0.75 and 0.87 respectively.

CONCLUSIONS

The simplified risk scoring system was able to stratify oral cancer and oral potentially malignant disorders risk with satisfactory sensitivity and specificity and can be applied in risk-based disease screening.

Image collection and annotation platforms to establish a multi-source database of oral lesions

OBJECTIVE

To describe the development of a platform for image collection and annotation that resulted in a multi-sourced international image dataset of oral lesions to facilitate the development of automated lesion classification algorithms.

MATERIALS AND METHODS

We developed a web-interface, hosted on a web server to collect oral lesions images from international partners. Further, we developed a customised annotation tool, also a web-interface for systematic annotation of images to build a rich clinically labelled dataset. We evaluated the sensitivities comparing referral decisions through the annotation process with the clinical diagnosis of the lesions.

RESULTS

The image repository hosts 2474 images of oral lesions consisting of oral cancer, oral potentially malignant disorders and other oral lesions that were collected through MeMoSA^® UPLOAD. Eight-hundred images were annotated by seven oral medicine specialists on MeMoSA^® ANNOTATE, to mark the lesion and to collect clinical labels. The sensitivity in referral decision for all lesions that required a referral for cancer management/surveillance was moderate to high depending on the type of lesion (64.3%-100%).

CONCLUSION

This is the first description of a database with clinically labelled oral lesions. This database could accelerate the improvement of AI algorithms that can promote the early detection of high-risk oral lesions.

Assessment of the oral cancer control activities through care seeking behavior of hospital attendees and their level of awareness

Oral cancer is the most common cancer among males in the Sri Lankan population. The aim of this study was to assess the health seeking behaviors and associated factors for OPMD. A hospital based descriptive cross-sectional study was conducted among Out Patients Department attendees of the Institute of Oral Health, Maharagama, from July 1, 2018 to December 31, 2019 by administering a questionnaire followed by an intra oral examination. The total number of 110 OPMD/oral cancer patients were identified. Awareness on OPMD was that 40 ​%. Majority were unaware of the danger of areca nut and alcohol use. Out of the identified cases during oral examination, 47.3 ​% were incidental findings while only 7.3 ​% were referred by the General Medical Practitioners (GMP). None were referred by the Primary Health Care (PHC) staff. The level of awareness on OPMD and its risk factors were very low. Incidental findings during the dental screening being the main mode of detection of OPMD, highlights the importance of conducting opportunistic screening at dental settings. Implementation of the Risk Factor Model (RFM) approach for the early detection of oral cancer through PHC staff and GMP is validated to encourage more early referrals.

Oral Cancer Screening: Past, Present, and Future

Oral cancer is a major public health problem, and there is an increasing trend for oral cancer to affect young men and women. Public awareness is poor, and many patients present with late-stage disease, contributing to high mortality. Oral cancer is often preceded by a clinical premalignant phase accessible to visual inspection, and thus there are opportunities for earlier detection and to reduce morbidity and mortality. Screening asymptomatic individuals by systematic visual oral examinations to detect the disease has been shown to be feasible. A positive screen includes both oral cancer and oral potentially malignant disorders. We review key screening studies undertaken, including 1 randomized clinical trial. Screening of high-risk groups is cost-effective. Strengths and weaknesses of oral cancer screening studies are presented to help guide new research in primary care settings and invigorated by the prospect of using emerging new technologies that may help to improve discriminatory accuracy of case detection. Most national organizations, including the US Preventive Services Task Force, have so far not recommended population-based screening due a lack of sufficient evidence that screening leads to a reduction in oral cancer mortality. Where health care resources are high, opportunistic screening in dental practices is recommended, although the paucity of research in primary care is alarming. The results of surveys suggest that dentists do perform oral cancer screenings, but there is only weak evidence that screening in dental practices leads to downstaging of disease. Where health care resources are low, the feasibility of using primary health care workers for oral cancer screening has been tested, and measures indicate good outcomes. Most studies reported in the literature are based on 1 round of screening, whereas screening should be a continuous process. This review identifies a huge potential for new research directions on screening for oral cancer.

Evaluation of a social marketing campaign for the early detection of oral potentially malignant disorders and oral cancer: Sri Lankan experience

Introduction

The present study evaluated a national social marketing campaign (SMC) conducted in 2008, with the ultimate aim of improving control of oral cancer in Sri Lanka. The approach was based on our published Risk Factor Model (RFM).

Methods

Social marketing tools were developed to educate the public on the major risk factors for oral cancer. A cross-sectional community-based cluster survey was carried out in 2013 by interviewing 491 citizens >25 years of age to assess any improvements to the level of disease awareness in the community. Changes in the number of case presentations were obtained from registrations at Government Hospital Dental Clinics (GHDC) from the year 2008-2015.

Results

A random sample of 491 members of the public was interviewed in 2013. Most (93%) were aware of oral cancer; but only 45.4% of oral potentially malignant disorders (OPMD). Statistically significant improvements were observed on awareness of oral cancer and OPMD and of the risk factors for oral cancer. A marked increase in the detection of oral leukoplakia and of oral cancer occurred in the GHDC surveillance system in the years 2012 and 2013, at the time the SMC campaign was implemented.

Conclusion

The improvement in public awareness of oral cancer and of its major risk factors, and the changed public behavior seen in the increased attendance at healthcare facilities for mouth examination, may be attributed, at least in part, to our SMC. Such Risk Factor-based approaches to social marketing are proposed for control of oral cancer.

Comparison of the accuracy of diagnoses of oral potentially malignant disorders with dysplasia by a general dental clinician and a specialist using the Taiwanese Nationwide Oral Mucosal Screening Program

Screening for oral potentially malignant disorders (OPMDs) with dysplasia in high-risk groups is suggested in countries with a high prevalence of the disorders. This study aimed to compare the accuracy of diagnoses of OPMDs with dysplasia made by a primary examiner (general dental clinician) and a specialist (oral and maxillofacial surgeon) using the current Taiwanese Nationwide Oral Mucosal Screening Program (TNOMSP). A total of 134 high-risk participants were enrolled for oral mucosal screening via the TNOMSP. A primary examiner and a specialist examined each participant. Mucosal biopsies were obtained and subjected to histopathological analysis. The OPMD most frequently diagnosed by the primary examiner was thin homogeneous leukoplakia (48/134; 35.8%), and in 39/134 participants (29.1%) the diagnosis was uncertain, but abnormalities were suggested. The OPMDs most frequently diagnosed by the specialist were erythroleukoplakia (23/134; 17.2%) and thin homogeneous leukoplakia (21/134; 15.7%), and 51/134 participants (38.1%) were diagnosed with other diseases. Via histopathology, 70/134 participants (52.3%) were diagnosed with dysplasia, and 58/134 (43.3%) were diagnosed with benign conditions. The specialist's diagnoses exhibited a higher specificity, positive predictive value, and accuracy than the primary examiners. A specialist using the current TNOMSP for high-risk participants diagnosed OPMDs with dysplasia more accurately than a primary examiner. Early diagnosis of high-risk OPMDs is crucial in countries with a high prevalence of the disorders. Proficient examination via the current TNOMSP by trained clinician is effective for the management of OPMDs with dysplasia.

Screening for oral cancer: Future prospects, research and policy development for Asia

Although the incidence of oral cavity cancer is high among low and middle income countries in Asia where the risk habits (tobacco smoking, tobacco chewing and betel quid use) are common, the benefits for introducing oral cancer screening for the whole population in these countries still remains controversial. It is disappointing, but not surprising that many of studies, without control arms, could not provide a clear answer as to whether screening is effective in reducing mortality or combating rising incidence trends. Only one Indian study that reported a randomized controlled trial (RCT) elucidated that mass screening for high risk groups could significantly reduce the cancer mortality or down-stage cancers detected by screening. Several professional organizations that considered any potential benefits of oral cancer screening remain unconvinced that the current knowledge on its natural history, available tests and interventions to treat potentially malignant disorders satisfy the desirable criteria to recommend organized screening for oral cancer. In this review we discuss advantages and disadvantages for oral cancer screening particularly with reference to high incidence countries in Asia. If screening is undertaken, we propose that it is targeted to high risk groups and to combine screening with education on risky life-styles so that overall incidence can be reduced in the future. Further research on increasing public awarenes and impact of professional education such as e-learning to reduce diagnostic delays, studies on the natural history of oral potentially malignant disorders and cancer, comprehensive tobacco and areca nut cessation programs, developing tools to identify high-risk individuals and high-risk lesions are proposed.

A personalized computational model predicts cancer risk level of oral potentially malignant disorders and its web application for promotion of non-invasive screening

BACKGROUND

Despite their high accuracy to recognize oral potentially malignant disorders (OPMDs) with cancer risk, non-invasive oral assays are poor in discerning whether the risk is high or low. However, it is critical to identify the risk levels, since high-risk patients need active intervention, while low-risk ones simply need to be follow-up. This study aimed at developing a personalized computational model to predict cancer risk level of OPMDs and explore its potential web application in OPMDs screening.

METHODS

Each enrolled patient was subjected to the following procedure: personal information collection, non-invasive oral examination, oral tissue biopsy and histopathological analysis, treatment, and follow-up. Patients were randomly divided into a training set (N = 159) and a test set (N = 107). Random forest was used to establish classification models. A baseline model (model-B) and a personalized model (model-P) were created. The former used the non-invasive scores only, while the latter was incremented with appropriate personal features.

RESULTS

We compared the respective performance of cancer risk level prediction by model-B, model-P, and clinical experts. Our data suggested that all three have a similar level of specificity around 90%. In contrast, the sensitivity of model-P is beyond 80% and superior to the other two. The improvement of sensitivity by model-P reduced the misclassification of high-risk patients as low-risk ones. We deployed model-P in web.opmd-risk.com, which can be freely and conveniently accessed.

CONCLUSION

We have proposed a novel machine-learning model for precise and cost-effective OPMDs screening, which integrates clinical examinations, machine learning, and information technology.

Risk factors associated with gastric cancer in Mexico: education, breakfast and chili

BACKGROUND AND AIM

the aim of the study was to use a validated questionnaire to identify factors associated with the development of gastric cancer (GC) in the Mexican population.

METHODS

the study included cases and controls that were paired by sex and ± 10 years of age at diagnosis. In relation to cases, 46 patients with a confirmed histopathological diagnosis of adenocarcinoma-type GC, as reported in the hospital records, were selected, and 46 blood bank donors from the same hospital were included as controls. The previously validated Questionnaire to Find Factors Associated with Gastric Cancer (QUFA-GC©) was used to collect data. Odds ratio (OR) and 95% confidence interval (IC) were estimated via univariate analysis (paired OR). Multivariate analysis was performed by logistic regression. A decision tree was constructed using the J48 algorithm.

RESULTS

an association was found by univariate analysis between GC risk and a lack of formal education, having smoked for ≥ 10 years, eating rapidly, consuming very hot food and drinks, a non-suitable breakfast within two hours of waking, pickled food and capsaicin. In contrast, a protective association against GC was found with taking recreational exercise and consuming fresh fruit and vegetables. No association was found between the development of GC and having an income that reflected poverty, using a refrigerator, perception of the omission of breakfast and time period of alcoholism. In the final multivariate analysis model, having no formal education (OR = 17.47, 95% CI = 5.17-76.69), consuming a non-suitable breakfast within two hours of waking (OR = 8.99, 95% CI = 2.85-35.50) and the consumption of capsaicin ˃ 29.9 mg capsaicin per day (OR = 3.77, 95% CI = 1.21-13.11) were factors associated with GC.

CONCLUSIONS

an association was found by multivariate analysis between the presence of GC and education, type of breakfast and the consumption of capsaicin. These variables are susceptible to intervention and can be identified via the QUFA-GC

Betel quid chewing among adult male immigrants from the Indian subcontinent to Italy

OBJECTIVE

Betel quid chewing (BQC) is an important oral cancer risk factor widespread in the Indian subcontinent. This usage also is common among migrants from this region. As the number of immigrants from South-East Asia is dramatically increasing in Italy, this survey was aimed at investigating BQC prevalence among immigrants from the Indian subcontinent.

SUBJECTS AND METHODS

First-generation adult male immigrants coming from Pakistan, India, Sri Lanka, and Bangladesh, living in Rome, were consecutively selected. They were interviewed using a validated questionnaire. Descriptive statistics were performed, and factors associated to regular BQC were investigated through regression analysis.

RESULTS

A total of 211 subjects (mean age, 33.8 years) living in Rome for 11 years, on average, participated in the study. BQC prevalence was 37.9% with few differences between Pakistani, Sri Lankans, and Indians. Prevalence among Bangladeshi was 7.3%. 69% of the consumers chewed BQ at least twice daily, 90% chewed BQ with tobacco; 30.3% subjects were smokers and chewers. Chewing parents, smoking, health illiteracy were associated with BQC. Most chewers believed that BQ helps to relieve stress.

CONCLUSIONS

The number of oral cancers in Italy is expected to increase because of BQC dissemination. Therefore, specific awareness campaigns directed to residents of South-East Asian origin are needed.

Association of DSM-5 Betel-Quid Use Disorder With Oral Potentially Malignant Disorder in 6 Betel-Quid Endemic Asian Populations

IMPORTANCE

Betel-quid (BQ) is the fourth most popular psychoactive agent worldwide. An emerging trend across Asia is the addictive consumption of BQ, which is associated with oral cancer and other health consequences.

OBJECTIVE

To investigate the validity and pattern of DSM-5-defined BQ use disorder (BUD) and its association with oral potentially malignant disorder (OPMD) among Asian populations.

DESIGN, SETTING, AND PARTICIPANTS

In-person interviews were conducted from January 1, 2009, to February 28, 2010, among a random sample of 8922 noninstitutionalized adults from the Asian Betel-quid Consortium study, an Asian representative survey of 6 BQ-endemic populations. Statistical analysis was performed from January 1, 2015, to December 31, 2016.

MAIN OUTCOMES AND MEASURES

Participants were evaluated for BUD using DSM-5 criteria for substance use disorder and for OPMD using a clinical oral examination. Current users of BQ with 0 to 1 symptoms were classified as having no BUD, those with 2 to 3 symptoms as having mild BUD, those with 4 to 5 symptoms as having moderate BUD, and those with 6 or more symptoms as having severe BUD.

RESULTS

Among the 8922 participants (4564 women and 4358 men; mean [SD] age, 44.2 [0.2] years), DSM-5 symptoms showed sufficient unidimensionality to act as a valid measure for BUD. The 12-month prevalence of DSM-5-defined BUD in the 6 study populations was 18.0% (mild BUD, 3.2%; moderate BUD, 4.3%; and severe BUD, 10.5%). The 12-month proportion of DSM-5-defined BUD among current users of BQ was 86.0% (mild BUD, 15.5%; moderate BUD, 20.6%; and severe BUD, 50.0%). Sex, age, low educational level, smoking, and drinking were significantly associated with BUD. Among individuals who used BQ, family use, high frequency of use, and amount of BQ used were significantly linked to moderate to severe BUD. Compared with individuals who did not use BQ, those who used BQ and had no BUD showed a 22.0-fold (95% CI, 4.3-112.4) risk of OPMD (P < .001), whereas those with mild BUD showed a 9.6-fold (95% CI, 1.8-56.8) risk (P = .01), those with moderate BUD showed a 35.5-fold (95% CI, 4.3-292.3) risk (P = .001), and those with severe BUD showed a 27.5-fold (95% CI, 1.6-461.4) risk of OPMD (P = .02). Individuals with moderate to severe BUD who used BQ and had the symptom of tolerance had a 153.4-fold (95% CI, 33.4-703.6) higher risk of OPMD than those who did not use BQ, and those with moderate to severe BUD who used BQ and had a larger amount or longer history of BQ use had an 88.9-fold (95% CI, 16.6-476.5) higher risk of OPMD than those who did not use BQ.

CONCLUSIONS AND RELEVANCE

This international study gathered data about BQ users across 6 Asian populations, and it demonstrates that DSM-5 symptoms could fulfill a BUD construct. Most current Asian users of BQ already have BUD, which is correlated with risk of OPMD. Among individuals with moderate to severe BUD who used BQ, tolerance and a larger amount or longer history of BQ use are the key symptoms that correlated with enhanced risk of OPMD. These findings play an important role in providing a new indication of an additional psychiatric management plan for users of BQ who have BUD.

Analysis of images for detection of oral epithelial dysplasia: A review

This paper provides a review of various image analysis approaches that have been previously used for recognition of dysplasia in images of the epithelium of the oral cavity. This domain has become especially admissible with the uncovering of the importance of image analysis which can probably be an aid to subjective diagnosis by histopathologists. Oral malignancy is a rampant form of cancer found among people of the Indian subcontinent due to various deleterious habits like consumption of tobacco, areca nut, betel leaf etc. Oral Submucous Fibrosis, a precancer, whose pathological category falls between normal epithelium and epithelial dysplasia, is caused because of these habits and can ultimately lead to oral cancer. Hence early detection of this condition is necessary. Image analysis methods for this purpose have an enormous potential which can also reduce the heavy workload of pathologists and to refine the criterion of interpretation. This paper starts with a critique of statistics of oral carcinoma in India and distribution of cancer in intra-oral sites and moves on to its causes and diagnostic approaches including causative agents, problems in curative approach and importance of image analysis in cancer detection. The various image analysis methods to appraise the cytological and architectural changes accompanied by Oral Epithelial Dysplasia in the images of the oral epithelial region have been described in relation to 2005 WHO Classification System and it was found that in future, analysis of images based on the mentioned methods has the potential in better interpretation and diagnosis of oral carcinoma.

Cytotoxic effect of Erythroxylum daphnites extract is associated with G1 cell cycle arrest and apoptosis in oral squamous cell carcinoma

Plant-derived molecules showing antineoplastic effects have recently gained increased attention as potential adjuvants to traditional therapies for various cancers. Cerrado biome in Brazil contains high floral biodiversity, but knowledge about the potential therapeutic effects of compounds derived from that flora is still limited. The present study investigated the antineoplastic activity of Erythroxylum daphnites Mart., a Brazilian native plant from Cerrado biome, in the SCC-9 oral squamous cell carcinoma cell line. Cells were treated with various concentrations of hexane extract of Erythroxylum daphnites leaves (EDH) and assessed for cytotoxicity, proliferation, and apoptosis. Thin layer chromatography was conducted to characterize the substances present in EDH. Our results showed that EDH exerted anti-proliferative effects in SCC-9 cells by stabilizing the cell cycle at G1 phase in association with reduced intracellular levels of cyclins D and E and increased level of p21. EDH also demonstrated pro-apoptotic properties, as shown by an increased expression of caspase-3. Triterpenes were the major constituents of EDH. Our findings demonstrated a cytotoxic effect of EDH against SCC-9 cells in vitro mediated by the restraint of cellular proliferation and induction of apoptosis. Taken together, these findings support EDH constituents as potential therapeutic adjuvants for oral cancer.

Evaluation of the utilization of primary healthcare staff for control of oral cancer

Background:

Population-based screening programmes utilizing primary healthcare (PHC) staff have been undertaken in several countries with high incidence of oral cancer and oral potentially malignant disorders (OPMDs).

Objective:

The main objective of this study is to re-evaluate the utilization of PHC staff for the detection of OPMD and the early detection of oral cancer.

Methods:

A cross-sectional community-based study was done in the Sabaragamuwa province in Sri Lanka by conducting interview and oral examination on 1029 subjects aged 30 years or more, over a 1 year period from November 2006. The study protocol included an interviewer-administered questionnaire to gather sociodemographic factors and lifestyle habits. A 2-day training programme involving didactic sessions followed by practical field training was held for all local PHC staff ( n = 67). Subjects screened by PHC staff were re-examined by the principal investigator (PI) to assess the validity of the screening.

Results:

A total of 685 subjects were screened by both PHC staff and the PI. In terms of the detection of any abnormality, sensitivity of the screening by PHC workers was 63%, with a specificity of 82.6%, a positive predictive value (PPV) of 24.8% and negative predictive value of 96.1%. Of the various OPMDs, poor agreement was noted in the detection of early oral submucous fibrosis. Among intra-oral sites missed by PHC staff, surprisingly high numbers were in the buccal mucosa and commissures.

Conclusion:

Low sensitivity and PPV in the present study indicate the necessity for improved training and facilities for better visualization of all intra-oral sites and/or an entirely different approach. An alternative strategy based on determining risk factors in the lives of individuals, with referral to local government dental clinics, could be a better option for screening for early detection of oral cancer in the South Asian scenario.

A risk factor-based model for upper aerodigestive tract cancers in India: predicting and validating the receiver operating characteristic curve

BACKGROUND

A study was conducted to develop and validate a screening model using risk scores to identify individuals at high risk for developing upper aerodigestive tract (UADT) cancers in an Indian population.

METHODS

A hospital-based case-control study (n = 480) was conducted in Pune, India. We assessed risk factors for UADT cancers by administering a questionnaire through face-to-face interviews. We developed a risk factor model based on the statistically significant risk factors in multiple logistic regression. A total, single risk score was calculated per individual based on the adjusted odds ratio for each of their risk factors. Standard receiver operator characteristic curve was plotted for the total score and the presence of UADT cancers. The stratification ability of the model was determined using the c-statistic. The optimal criterion value was determined at the point on curve at which the Youden's index was maximal. Confidence intervals were calculated by bootstrapping.

RESULTS

Total risk score for each individual ranged from 0 to 26. Area under the receiver operating characteristic curve (95.8; P < 0.001) suggests strong predictive ability. A risk score criterion value of ≤10 produced optimal sensitivity (93.5%), specificity (71.1%), false-positive rate (28.8%), false-negative rate (6.4%), positive predictive value (74.8%), and negative predictive value (96.6%).

CONCLUSION

This risk factor-based model has the potential of satisfactorily screening and detection of UADT cancers at its early stage in a high-risk population like India. The identified at-risk individuals can then be targeted for clinical examination and for focused preventive/treatment measures at the hospital.

A comparison of health state utility values associated with oral potentially malignant disorders and oral cancer in Sri Lanka assessed using the EQ-5D-3 L and the EORTC-8D

Background

It has been suggested that the EQ-5D-3 L preference-based measure of health outcome lacks sensitivity to discriminate between health states in cancer patients. An alternative approach is to use a disease (cancer) specific preference-based measure, such as the EORTC-8D. A limited number of comparisons have been made between generic and disease specific preference-based measures. The aim of this study was to compare the utility scores from the EQ-5D-3 L and the EORTC-8D in a group of patients with oral cancer or with oral potentially malignant disorders (OPMD).

Methods

Patients (n = 151) with OPMD or oral cancer were recruited consecutively from six hospitals in Sri Lanka. All participants completed both the EQ-5D-3 L and the EORTC's QLQC-30 instrument. The Sri Lankan EQ-5D-3 L and EORTC-8D scoring algorithms were employed to estimate utility scores. The utility scores from the two instruments were compared for discrimination, responsiveness and correlation.

Results

There were significant differences across the two utility scores. The EQ-5D-3 L showed better discrimination than EORTC-8D with higher effect sizes. There were higher ceiling effects observed in the EQ-5D-3 L. There was poor correlation between the dimensions of the two instruments except for the mobility and physical functions.

Conclusion

The two instruments captured different aspects of quality of life. The EQ-5D-3 L demonstrated better discrimination than the EORTC-8D. In mild conditions EORTC-8D was more responsive and we recommend further validation of this instrument in diverse cancer conditions.

Betel quid chewing without tobacco: a meta-analysis of carcinogenic and precarcinogenic effects

Betel quid without tobacco is an important factor influencing the incidences of oral cancer and precancer. This study systematically evaluated the associations between betel quid containing no tobacco and oral cancer and precancer, with implications for the prevention of oral cancer. We searched MEDLINE, ISI Web of Science, and EMBASE (to April 2011) and retrieved studies that investigated the relationship between chewing betel quid and oral cancer (or precancer). We performed a meta-analysis to summarize the published data and describe the prevalence of betel quid use with regard to cancerous diseases. In all, 19 eligible studies that reported odds ratios and 95% confidence intervals for oral cancer with respect to betel quid were included. The analysis identified an association suggesting that betel quid might be an important risk factor for oral cancer and precancer. The results of this review suggest that betel-chewing-cessation programs should be developed to help prevent oral diseases.

Gastric cancer research in Mexico: A public health priority

This study aimed review studies conducted on Mexican patients diagnosed with gastric cancer and/or diseases associated with its development, in which at least one Mexican institute has participated, and to assess their contributions to the primary and secondary prevention of this disease. A search of the Medline database was conducted using the following keywords: gastric/stomach cancer, Mexico. Studies of the Mexican population were selected in which at least one Mexican Institute had participated and where the findings could support public policy proposals directed towards the primary or secondary prevention of gastric cancer. Of the 148 studies found in the Medline database, 100 were discarded and 48 were reviewed. According to the analysis presented, these studies were classified as: epidemiology of gastric cancer (5/48); risk factors and protectors relating to gastric cancer (9/48); relationship between Helicobacter pylori and pathologies associated with gastric cancer and the development of the disease (16/48); relationship between the Epstein-Barr virus and pathologies associated with gastric cancer and the development of the disease (3/48); molecular markers for the development of diseases associated with gastric cancer and gastric cancer (15/48). Mexico requires a program for the prevention and control of gastric cancer based on national health indicators. This should be produced by a multidisciplinary committee of experts who can propose actions that are relevant in the current national context. The few studies of gastric cancer conducted on the Mexican population in national institutes highlight the poor connection that currently exists between the scientific community and the health sector in terms of resolving this health issue. Public policies for health research should support projects with findings that can be translated into benefits for the population. This review serves to identify national research groups studying gastric cancer in the Mexican population.

Malignancy risk models for oral lesions

OBJECTIVES

The aim of this work was to assess risk habits, clinical and cellular phenotypes and TP53 DNA changes in oral mucosa samples from patients with Oral Potentially Malignant Disorders (OPMD), in order to create models that enable genotypic and phenotypic patterns to be obtained that determine the risk of lesions becoming malignant.

STUDY DESIGN

Clinical phenotypes, family history of cancer and risk habits were collected in clinical histories. TP53 gene mutation and morphometric-morphological features were studied, and multivariate models were applied. Three groups were estabished: a) oral cancer (OC) group (n=10), b) oral potentially malignant disorders group (n=10), and c) control group (n=8).

RESULTS

An average of 50% of patients with malignancy were found to have smoking and drinking habits. A high percentage of TP53 mutations were observed in OC (30%) and OPMD (average 20%) lesions (p=0.000). The majority of these mutations were GC TA transversion mutations (60%). However, patients with OC presented mutations in all the exons and introns studied. Highest diagnostic accuracy (p=0.0001) was observed when incorporating alcohol and tobacco habits variables with TP3 mutations.

CONCLUSIONS

Our results prove to be statistically reliable, with parameter estimates that are nearly unbiased even for small sample sizes. Models 2 and 3 were the most accurate for assessing the risk of an OPMD becoming cancerous. However, in a public health context, model 3 is the most recommended because the characteristics considered are easier and less costly to evaluate.

Diet and risk of oral potentially malignant disorders in rural Sri Lanka

BACKGROUND

While the protective role of antioxidant nutrients against cancer is well established, data on Asian diets in patients with oral cancer are meagre.

METHODS

A total of 1029 subjects over 30 years of age were investigated on their dietary practices in the Sabaragamuwa province (Sri Lanka) in 2006-07. Data collection tools were an interviewer-administered questionnaire, a three-day food diary and an examination of the oral cavity. Subjects identified with Oral Potentially Malignant Disorders (OPMD) and disease-free controls were analysed in a case-control fashion. Among the OPMDs, those with leukoplakia were separately considered. A further subgroup analysis was undertaken for β-carotene-rich foods. The analysis was stratified by portions of fruit/vegetables consumed as five or more portions and two or more portions daily.

RESULTS

A low BMI (<18.5) was a significant independent risk factor for the development of OPMD. More than half of both cases and controls consumed less than two portions of fruit/vegetables per day and only 20 subjects consumed more than five portions per day. Intake of more than two portions per day of β-carotene-containing fruits/vegetables significantly reduced the risk of having an OPMD and leukoplakia (OR = 0.5; 95% CI, 0.3-0.9). The significant differences observed with BMI and fruits/vegetables were attenuated when adjusted for betel quid chewing, smoking and alcohol use.

CONCLUSIONS

This study discloses prevailing under-nutrition in this rural population with very low daily consumption of fruit/vegetables. Cancer preventive properties in their diets are limited and are swamped by the known carcinogenic agents associated with use of betel quid, tobacco and alcohol.

Global oral health inequalities in incidence and outcomes for oral cancer: causes and solutions

The mouth and oropharynx are among the ten most common sites affected by cancer worldwide, but global incidence varies widely. Five-year survival rates exceed 50% in only the best treatment centers. Causes are predominantly lifestyle-related: Tobacco, areca nut, alcohol, poor diet, viral infections, and pollution are all important etiological factors. Oral cancer is a disease of the poor and dispossessed, and reducing social inequalities requires national policies co-ordinated with wider health and social initiatives - the common risk factor approach: control of the environment; safe water; adequate food; public and professional education about early signs and symptoms; early diagnosis and intervention; evidence-based treatments appropriate to available resources; and thoughtful rehabilitation and palliative care. Reductions in inequalities, both within and between countries, are more likely to accrue from the application of existing knowledge in a whole-of-society approach. Basic research aimed at determining individual predisposition and acquired genetic determinants of carcinogenesis and tumor progression, thus allowing for targeted therapies, should be pursued opportunistically.