The effectiveness of community-based visual screening and utility of adjunctive diagnostic aids in the early detection of oral cancer

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

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

Oral cancer: Current status and public health perspectives

Despite advances in surgical and oncological treatments, the incidence and five-year survival rates (~50 percent) of oral cancers (OC) have not improved over the last decades and remain a major public health problem. Seventy percent are still diagnosed at a late stage (T3 or T4), with an average delay in diagnosis of two to five months. As the cure and survival of patients are directly related to the development stage of the tumor at the time of diagnosis, the objective of this work was to analyze all the determinants related to oral cancer and to propose new clinical approaches for diagnosis and screening. A proposal for new models of screening, training, and concrete action to improve public awareness of the major global problem of OC is made. The strengths and weaknesses of OC screening studies need to be objectively understood to effectively guide and energize testing in primary care settings, with the prospect of using new and emerging technologies that can help improve the discriminatory accuracy of case detection. Most national organizations have not, to date, recommended population-based mass screening, due to a lack of sufficient scientific evidence of associated mortality reduction. Where health care resources are high, opportunistic individual screening is recommended, although the low diagnostic capacity of front-line clinicians is alarming.

Challenges in the Early Diagnosis of Oral Cancer, Evidence Gaps and Strategies for Improvement: A Scoping Review of Systematic Reviews

Simple Summary

Oral cancer presents a worldwide incidence of 377,713 new cases and 177,757 deaths per year (GLOBOCAN, IARC, WHO). Oral squamous cell carcinoma (OSCC) accounts for approximately 90% of oral malignancies and has a 5-year mortality rate close to 50%. We aim to better understand, based on the evidence, and to discuss in depth, the reasons for the diagnostic delay of oral cancer by reviewing systematic reviews and meta-analyses. We also aim to, identify gaps in evidence, recommend future lines of research that should be implemented, and formulate strategies for improvement.

Abstract

Oral cancer is a growing problem, accounting for 377,713 worldwide new cases per year, and 177,757 deaths annually and representing a 5-year mortality rate close to 50%, which is a considerable mortality that has not decreased substantially in the last 40 years. The main cause of this high mortality is related to the diagnosis of a high percentage of oral cancers in advanced stages (stages III and IV) in which treatment is complex, mutilating or disabling, and ineffective. The essential cause of a cancer diagnosis at a late stage is the delay in diagnosis, therefore, the achievement of the objective of improving the prognosis of oral cancer involves reducing the delay in its diagnosis. The reasons for the delay in the diagnosis of oral cancer are complex and involve several actors and circumstances—patients, health care providers, and health services. In this paper, we present the results of a scoping review of systematic reviews on the diagnostic delay in oral cancer with the aim to better understand, based on the evidence, and discuss in depth, the reasons for this fact, and to identify evidence gaps and formulate strategies for improvement.

Dentists Behavioral Factors Influencing Early Detection of Oral Cancer: Direct Clinical Observational Study

This study aimed to investigate the possible factors affecting dentists' behavior relating to performing oral cancer examinations as part of routine clinical examination. A total of 95 direct clinical observation sessions-utilizing an instrument consisting of 19 evidence-based observational criteria for oral cancer examinations-were observed by four calibrated dentists. Thirty-two final-year students, 32 interns, and 31 faculty members of Jazan Dental School were examined between April 9 and May 4, 2017. A descriptive analysis was conducted to investigate the frequencies/percentages of the performed observing criteria by all examiners. ANOVA and Tukey tests were carried out to investigate the difference between the examiner groups. A total number of 32 patients participated in the study, whereby each patient was examined by three different examiners from each group, as well as by the attending observer/s. Fewer than 50% of the examiners performed the clinical steps necessary for an oral cancer examination-for example, taking into account past medical history, as well as extra and intra-oral examinations. More than 90% of the examiners examined hard tissue, whereas fewer than 30% of them educated their patients about possible risk factors. A significant difference between examiner groups was found in favor of faculty members. A gap between knowledge and actual practice of oral cancer examinations was evident: majority of participants failed to perform the necessary steps for an oral cancer examination. Previous experience and confidence in performing oral cancer examination are possible explanations for the dentist's behavior toward oral cancer examination.

Cost-effectiveness of oral cancer screening approaches by visual examination: Systematic review

The present study is the first systematic review of papers that have performed a full economic evaluation on oral cancer screening strategies using visual oral examination. The review questions were (1) Is screening a cost-effective strategy in oral cancer? (2) What is the most cost-effective strategy among the different screening approaches in oral cancer? The main outcome measure was the incremental cost-effectiveness ratio. The study identifies and reviews seven full economic evaluations. The included studies scored 75%-100% on the methodological appraisal. Majority of the studies reports that oral cancer screening is a cost-effective strategy, especially in an opportunistic setting and high-risk subset of patients. The results were sensitive to cost and effectiveness parameters. Oral cancer screening, though found cost-effective, the uncertainty around these parameters necessitates additional studies that include better estimates in the modeling assessments. The heterogeneity in studies limited comparison and generalization.

Countermeasure and opportunistic screening systems for oral cancer

OBJECTIVES

Tokyo Dental College started oral cancer screening in cooperation with a local dental association in 1992. Reveal the usefulness of Countermeasure and Opportunistic Screening Systems for Oral Cancer. The actual results of countermeasure and opportunistic oral cancer screening systems are reported.

MATERIALS AND METHODS

Countermeasure screening for the public was performed in each region, and opportunistic screening was performed in a general dental clinic of a cooperating physician.

RESULTS

In countermeasure screening, 19,721 persons were checked from 1992 to 2018; the gender ratio was 1:3. The close examination rate was 4.45%. The detection rates of oral cancer and oral potentially malignant disorders were 0.13% and 1.85%, respectively. In opportunistic screening, 29,912 persons were checked from 2006 to 2018; the gender ratio was 2:3. The close examination rate was 2.33%. The detection rates of oral cancer and oral potentially malignant disorders were 0.08% and 2.15%, respectively. The close examination rate was significantly lower in opportunistic screening than in countermeasure screening. The oral cancer detection rates and the positive predictive value for cancer were equivalent. In addition, the detection rate of oral potentially malignant disorders was significantly higher in opportunistic screening than in countermeasure screening.

CONCLUSION

Oral cancer detection rates were equivalent between countermeasure and opportunistic screenings, and opportunistic screening were more effective on number of participants and the close examination rate, and the detection rate of oral potentially malignant disorders.

Outcomes of the National Head and Neck Cancer Awareness and Screening Campaign in Oman

Objectives

The prognosis of head and neck cancer (HNC) depends substantially on disease stage at the time of diagnosis. Unfortunately, the majority of HNC patients present at relatively late stages. In Oman, a national screening campaign was conducted to increase public awareness of HNC and encourage early detection. This study aimed to report the outcomes of that campaign.

Methods

The campaign took the form of biannual events conducted at a tertiary care centre and in public malls in Muscat, Oman from April 2015 to July 2019. Data were collected from participants using the Head and Neck Cancer Alliance screening form. Otolaryngologists and oral maxillofacial surgeons performed a thorough physical evaluation of the head and neck region.

Results

Of the 1,500 individuals visiting the hospital and malls during the campaign events, a total of 509 agreed to undergo screening (response rate: 33.9%). Of these, 12.8% had positive screening results and 5.9% required further evaluation. However, none of the cases with suspicious findings were found to be malignant after a thorough evaluation. Overall, 16.9% of the participants were aware of the early signs of HNC; in addition, 5.5% knew how to perform an oral self-examination.

Conclusion

Screening is a simple and safe method for the prevention and early detection of HNC. Mass screening and public awareness programmes may help to reduce the burden of this disease in Oman.

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.

Current Practice and Emerging Molecular Imaging Technologies in Oral Cancer Screening

Oral cancer is one of the most common cancers globally. Survival rates for patients are directly correlated with stage of diagnosis; despite this knowledge, 60% of individuals are presenting with late-stage disease. Currently, the initial evaluation of a questionable lesion is performed by a conventional visual examination with white light. If a lesion is deemed suspicious, a biopsy is taken for diagnosis. However, not all lesions present suspicious under visual white light examination, and there is limited specificity in differentiating between benign and malignant transformations. Several vital dyes, light-based detection systems, and cytology evaluation methods have been formulated to aid in the visualization process, but their lack of specific biomarkers resulted in high false-positive rates and thus limits their reliability as screening and guidance tools. In this review, we will analyze the current methodologies and demonstrate the need for specific intraoral imaging agents to aid in screening and diagnosis to identify patients earlier. Several novel molecular imaging agents will be presented as, by result of their molecular targeting, they aim to have high specificity for tumor pathways and can support in identifying dysplastic/cancerous lesions and guiding visualization of biopsy sites. Imaging agents that are easy to use, inexpensive, noninvasive, and specific can be utilized to increase the number of patients who are screened and monitored in a variety of different environments, with the ultimate goal of increasing early detection.

Comparative efficacy of chemiluminescence and toluidine blue in the detection of potentially malignant and malignant disorders of the oral cavity

Context:

Early detection of oral cancer is of paramount importance in determining the prognosis of oral cancer. Literature suggests that several diagnostic modalities have been proposed to aid a clinician in early detection of oral cancer without much conclusive evidence.

Aims:

The present study aims to compare toluidine blue and chemiluminescence screening methods in early detection of carcinoma in North Indian population and also to evaluate these methods with histopathological diagnosis.

Methods:

In this prospective study, 42 patients with clinically visible premalignant lesions were included. Demographic data were collected, and suspicious lesions were examined by chemiluminescence light (Vizilite) and followed by local application of toluidine blue (Mashberg's recommendation). Findings were recorded for each lesion under standard incandescent light as positive or negative. Biopsy and histopathological analysis of the tissues were performed.

Statistical Analysis:

Sensitivity, specificity and positive and negative predictive values for the chemiluminescence technique and toluidine blue were calculated for diagnostic tests.

Results and Conclusions:

In the present study, toluidine blue test was found to be moderately sensitive (63.33%) whereas chemiluminescence test (Vizilite) was found to be highly sensitive (90%); however, the test has limited specificity (50%). Thus, the study concluded that both toluidine blue and Vizilite can be used as an adjunct to simple, conventional visual examination and in screening procedure for oral potentially malignant disorders.

Screening Projects for Oral Carcinoma in Relation to Health Education and Patients' Compliance: Study on 600 Participants

Aims and Objectives:

The lack of information among the population regarding the existence of oral squamous cell carcinoma (OSCC) and the lack of attention and expertise in examining the oral cavity of dentists and clinicians still remain very worrying and could explain the high incidence of OSCC. The aim of this study is to evaluate the level of awareness of OSCC among 600 participants from Southern Italy.

Materials and Methods:

A 13-question survey was prepared and distributed to 600 participants divided into two subgroups, the first one of 300 patients referring to the Department of Neuroscience, Reproductive, and Odontostomatological Sciences, University Federico II of Naples, for the treatment of dental pathologies, and the second one of 300 patients referring to the Department of Internal Medicine of the Second University of Naples for the diagnosis and treatment of cardiovascular diseases. Statistical analysis consisted in the calculation of percentages related to the answers given by patients. Comparison of percentages was after performed between the two subgroups.

Result:

Only 175 participants (29.1%) knew about the existence of pathologies which can affect the oral mucosa, and only 46 (7.6%) were aware that carcinoma can arise in the oral cavity; 345 (57,5%) stated that they had periodical dental visits, at least once a year but none of them stated they had a visit for the identification of oral carcinomas.

Conclusion:

The data acquired must be taken into consideration to outline essential socio-healthcare educational projects on carcinoma and its risk factors, training programs to increase dentists and clinicians’ competences, and to evaluate the feasibility and effectiveness of oral carcinoma screening programs.

Oral Cancer Awareness Among Dental Patients in Omdurman, Sudan: a cross-sectional Study

Background

Oral cancer is a preventable disease. Its occurrence is mostly due to lifestyle. In Sudan, the use of smokeless tobacco (Toombak) has long been linked to oral cancer. Knowledge of the signs and symptoms of oral cancer may well aid in early diagnosis and treatment. This is bound to result in increasing survival rates, as well as reducing the oral cancer burden on the society. This study aimed to assess oral cancer awareness regarding knowledge of signs, symptoms, risk factors and sources of the information. Furthermore, it attempts to evaluate attitudes towards oral cancer screening and any previous experience of screening, amongst dental patients attending University of Science and Technology (UST) Dental Teaching Hospital. Omdurman, Sudan.

Methods

A hospital based cross-sectional study, interviewer-administered questionnaire was conducted amongst 500 adult patients attending the UST Dental Hospital during 2015.

Results

A total of 57.7% (286) of the individuals demonstrated good knowledge of signs and symptoms, whereas 49% (139) expressed good knowledge of risk factors of oral cancer. For the majority of the individuals 66.1% (290), the most common source of information about oral cancer was from the media, while 33.9% individuals (149), obtained knowledge from direct contact of health workers. The overwhelming majority, 93.2% (466) never screened for oral cancer despite their positive attitude towards it 66.4% (332). Knowledge of risk factors associated significantly with those reported positive attitude towards oral cancer screening and those reported direct contact with health workers as a source of information, (p ≤ 0.001). Moreover, females and those living in urban districts scores higher than their counterpart in knowledge of risk factor of oral cancer. In addition, those employed 58.6% (280) and 62.8% (164) with correct believes about oral cancer showed significant association with positive knowledge of signs and symptoms (p ≤ 0.05).

Conclusions

Awareness levels, knowledge of risk factors and identifying early signs and symptoms of oral cancer necessitate the need for more structured preventive programs using media. Dentists and health workers should do more because they have a pivotal role in early diagnosis by performing oral cancer screening, raising levels of knowledge and in rectifying misconceptions about oral cancer. This would entail a reduction in high rates of morbidity and mortality associated with oral cancer.

Electronic supplementary material

The online version of this article (doi:10.1186/s12903-017-0351-z) contains supplementary material, which is available to authorized users.

Population-based screening program for reducing oral cancer mortality in 2,334,299 Taiwanese cigarette smokers and/or betel quid chewers

BACKGROUND

To reduce oral cancer mortality, an organized, population-based screening program for the early detection of oral premalignancy and oral cancer was designed for high-risk individuals with habits of betel quid chewing, cigarette smoking, or both. The objective of this report was to evaluate the long-term effectiveness of this program in reducing the incidence of advanced disease and deaths from oral cancer.

METHODS

A nationwide, population-based screening program for oral cancer has been conducted in Taiwan since 2004. Residents aged ≥ 18 years with oral habits of cigarette smoking and/or betel quid chewing were invited. The standardized mortality ratio method was used to compare the observed numbers of advanced oral cancers and deaths from oral cancer among screening attendees with the expected numbers derived from mortality among nonattendees. An intention-to-treat analysis of the relative rate of reductions in advanced-stage oral cancers and oral cancer mortality also was conducted.

RESULTS

The overall screening rate was 55.1%. The relative risk of death from oral cancer was 0.53 (95% confidence interval [CI], 0.51-0.56) as a result of screening compared with the expected risk of oral cancer deaths in the absence of screening. The corresponding relative risk was 0.74 (95% CI, 0.72-0.77) after adjusting for self-selection bias. The relative risk of advanced oral cancer for the screened group versus the nonscreened group was 0.62 (95% CI, 0.59-0.64), which increased to 0.79 (95% CI, 0.76-0.82) after adjustment for self-selection bias.

CONCLUSIONS

An organized, population-based oral cancer screening program targeting more than 2 million Taiwanese cigarette smokers and/or betel quid chewers demonstrated the effectiveness of reducing stage III or IV oral cancers and oral cancer mortality. These evidence-based findings corroborate and support the screening strategy of oral visual inspection for the prevention of oral cancer among high-risk individuals in areas with a high incidence of oral cancer. Cancer 2017;123:1597-1609. © 2017 American Cancer Society.

Limits of application of initiated chemiluminescence in monitoring of oncological process of mucous membrane of mouth and larynx

Investigation into the limits of application of chemiluminescence (CL) methods in oncology still attracts the attention of researchers. In the present work we analyze the screening and monitoring of oncological processes (OP) in the mucous membrane of the mouth and larynx by initiated CL (ICL). Chemiluminescence has already been used by stomatologists to define the start of OP, but methods that reflect the metabolic changes in organism under cancer diagnostics still have not found their place. This work presents results of ICL on blood serum (BS) of patients with oncological diseases at different stages of medical treatment compared with those of healthy people. We found an essential metabolic difference only in types of OP that are characterized by two maxima on chemiluminograms. These OP represent only 12.81% of groups of patients with oncological diseases. The possibility to apply ICL methods to monitor operation quality and control medical treatment at different stages when the two ICL maxima are present is established. At present, the chemiluminograms with the two maxima are mostly informative, but this does not exclude the quantitative analysis of other ICL kinetic methods and is encouraging for their investigation. Any OP introduces changes in organism function and these should be reflected in the ICL. Copyright © 2016 John Wiley & Sons, Ltd.

How many individuals must be screened to reduce oral cancer mortality rate in the Western context? A challenge

OBJECTIVE

Controlling oral cancer (OC) through screening is appealing. Advantages of this are as follows: OC is often preceded by visible premalignant lesions, early-stage survival is threefold greater than late-stage survival, and visual screening is inexpensive. Disadvantages of this are as follows: high frequency of false positives, undemonstrated cost-effectiveness, and irregular screening attendance by high-risk individuals. Screening effectiveness in Western countries has not been proven, because of low OC prevalence, which disproportionally increases the number of individuals needed to screen (NNS) to decrease mortality. This study estimated the NNS to obtain an evident decrease in OC mortality rate in the UK.

METHODS

Data gathered from reliable databanks were used. NNS to detect one case (NNScase ) was estimated using a Bayesian approach. NNS to prevent one death (NNSdeath ) was assessed multiplying NNScase by the number of cases that must be screen-detected to prevent one death. NNS to decrease mortality rate by 1% (NNSmortality ) was assessed multiplying NNSdeath by 1% of annual OC deaths.

RESULTS

NNSmortality was overall 1 125 000 (95% confidence interval - 95CI, 690 000-1 870 000), males 551 000 (95CI, 337 000-916 000), and females 571 000 (95CI, 347 000-942 000).

CONCLUSIONS

An OC visual screening campaign capable of producing an evident decrease in mortality rate in the UK requires a large number of adults to be annually and regularly screened.

Assessing the accuracy of autofluorescence, chemiluminescence and toluidine blue as diagnostic tools for oral potentially malignant disorders--a clinicopathological evaluation

OBJECTIVES

Early detection of oral cancer and their precursors is the key to reducing the high mortality rate attributable to oral cancer. A variety of new chair-side diagnostic tools are currently available that may enhance oral mucosal examination and facilitate the detection of benign and malignant disorders. The aim of this study was to investigate the accuracy of autofluorescence, chemiluminescence and toluidine blue (TBlue) when used in combination against conventional oral examination and surgical biopsy for the detection and assessing risk status of oral potentially malignant disorders.

MATERIALS AND METHODS

A total of 126 patients, with white, red and mixed white and red patches were included. Following a comprehensive oral examination, all patients underwent a standard protocol of autofluorescence, chemiluminescence and TBlue examination. A surgical biopsy was performed to assess oral epithelial dysplasia.

RESULTS

Seventy patients had leukoplakia/erythroplakia and 44 had epithelial dysplasia. In relation to leukoplakia/erythroplakia, autofluorescence, chemiluminescence and TBlue showed a sensitivity of 87.1, 77.1 and 52.9 % and a specificity of 21.4, 26.8 and 67.9 %, respectively. For dysplasia cases, autofluorescence, chemiluminescence and TBlue showed sensitivity and specificity of 84.1, 77.3 and 56.8 % and 15.3, 27.8 and 65.8 %, respectively.

CONCLUSION

While all the three tests were useful in detecting oral mucosal changes, their accuracy in identifying oral potentially malignant disorders (OPMD) is questionable. However, in combination, the tests yielded better results, with improved specificity.

CLINICAL RELEVANCE

These research tools are helpful in specialist clinics but further studies are necessary to examine their role in screening in primary care settings.

Initial outcomes of an integrated outpatient-based screening program for oral cancers

OBJECTIVE

To evaluate the feasibility of an integrated outpatient-based screening program for oral cancer.

STUDY DESIGN

An automated system was used to refer high-risk patients presenting to the outpatient clinic for oral cavity examination. The outcomes between the screened and concurrently symptomatic cohorts were compared to assess the program's effectiveness at identifying oral cancers.

RESULTS

Among the 38,693 candidates flagged as high-risk patients by our automated referral system, a total of 8037 participants were recruited to our screened cohort; 1664 patients were identified with positive lesions, and 302 patients underwent a biopsy. Five patients were diagnosed with oral cancer and 121 with dysplastic precancers. The symptomatic cohort comprised 157 patients with oral cancers and 61 with precancers. The screening program identified earlier stages of oral cancers than in the symptomatic cohort.

CONCLUSION

Automated outpatient-based oral cancer screening programs may be a practicable strategy to identify precancerous lesions or early-stage cancers in high-risk adults.

Diagnostic modalities for squamous cell carcinoma: an extensive review of literature-considering toluidine blue as a useful adjunct

INTRODUCTION

Oral Squamous Cell Carcinomas have been considered as the most prevalent malignancies in the head and neck region and are frequently undiagnosed until symptomatic with an advanced stage of disease. So there is an urgent need to device methods for the detection of oral premalignant lesions and oral cancer at an early stage in order to improve the survival rate for patients. A number of tests have been done for the detection of oral cancer which include oral brush biopsy, the Vizilite, oral autofluorescence including chemiluscence, photodynamic detection, toluidine blue staining, methylene blue staining, incisional biopsy and many more.

MATERIAL

The article reviews various diagnostic modalities available at present for detection of squamous cell carcinomas and oral epithelial dysplasias based on advanced PUBMED search of the English language literature from the year 1972 to present in order to help us select the most suitable among them fulfilling the desired criteria of being non-invasive, highly specific and sensitive, economically viable, having a scope to be used for mass screening, easy to process, having low inter examiner variability and possibly not requiring high expertise to conduct and interpret the results.

CONCLUSION

After reviewing various diagnostic modalities, we conclude that toluidine blue staining emerges as a clear winner among all these and it can act as a valuable adjunct to incisional biopsy in detection of oral cancer and may not substitute it except in certain circumstances when its results are carefully correlated with the patient history and clinical characteristics of the mucosal disorder, considering the fact that incisional biopsy has been reported to cause dissemination of cancer cells in the circulation there by increasing the possibility of metastasis. We must emphasize that toludine blue is a screening modality and not a diagnostic procedure like biopsy and hence cannot replace a confirmatory biopsy as a whole.

Screening programmes for the early detection and prevention of oral cancer

BACKGROUND

Oral cancer is an important global healthcare problem, its incidence is increasing and late-stage presentation is common. Screening programmes have been introduced for a number of major cancers and have proved effective in their early detection. Given the high morbidity and mortality rates associated with oral cancer, there is a need to determine the effectiveness of a screening programme for this disease, either as a targeted, opportunistic or population-based measure. Evidence exists from modelled data that a visual oral examination of high-risk individuals may be a cost-effective screening strategy and the development and use of adjunctive aids and biomarkers is becoming increasingly common.

OBJECTIVES

To assess the effectiveness of current screening methods in decreasing oral cancer mortality.

SEARCH METHODS

We searched the following electronic databases: the Cochrane Oral Health Group's Trials Register (to 22 July 2013), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2013, Issue 6), MEDLINE via OVID (1946 to 22 July 2013), EMBASE via OVID (1980 to 22 July 2013) and CANCERLIT via PubMed (1950 to 22 July 2013). There were no restrictions on language in the search of the electronic databases.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of screening for oral cancer or potentially malignant disorders using visual examination, toluidine blue, fluorescence imaging or brush biopsy.

DATA COLLECTION AND ANALYSIS

Two review authors screened the results of the searches against inclusion criteria, extracted data and assessed risk of bias independently and in duplicate. We used mean differences (MDs) and 95% confidence intervals (CIs) for continuous data and risk ratios (RRs) with 95% CIs for dichotomous data. Meta-analyses would have been undertaken using a random-effects model if the number of studies had exceeded a minimum of three. Study authors were contacted where possible and where deemed necessary for missing information.

MAIN RESULTS

A total of 3239 citations were identified through the searches. Only one RCT, with 15-year follow-up met the inclusion criteria (n = 13 clusters: 191,873 participants). There was no statistically significant difference in the oral cancer mortality rates for the screened group (15.4/100,000 person-years) and the control group (17.1/100,000 person-years), with a RR of 0.88 (95% CI 0.69 to 1.12). A 24% reduction in mortality was reported between the screening group (30/100,000 person-years) and the control group (39.0/100,000) for high-risk individuals who used tobacco or alcohol or both, which was statistically significant (RR 0.76; 95% CI 0.60 to 0.97). No statistically significant differences were found for incidence rates. A statistically significant reduction in the number of individuals diagnosed with stage III or worse oral cancer was found for those in the screening group (RR 0.81; 95% CI 0.70 to 0.93). No harms were reported. The study was assessed as at high risk of bias.

AUTHORS' CONCLUSIONS

There is evidence that a visual examination as part of a population-based screening programme reduces the mortality rate of oral cancer in high-risk individuals. In addition, there is a stage shift and improvement in survival rates across the population as a whole. However, the evidence is limited to one study, which has a high risk of bias and did not account for the effect of cluster randomisation in the analysis. There was no evidence to support the use of adjunctive technologies like toluidine blue, brush biopsy or fluorescence imaging as a screening tool to reduce oral cancer mortality. Further RCTs are recommended to assess the efficacy and cost-effectiveness of a visual examination as part of a population-based screening programme in low, middle and high-income countries.

EDNRB and DCC salivary rinse hypermethylation has a similar performance as expert clinical examination in discrimination of oral cancer/dysplasia versus benign lesions

PURPOSE

Promoter hypermethylation has been recently proposed as a means for head and neck squamous cell carcinoma (HNSCC) detection in salivary rinses. In a prospective study of a high-risk population, we showed that endothelin receptor type B (EDNRB) promoter methylation in salivary rinses is a useful biomarker for oral cancer and premalignancy.

EXPERIMENTAL DESIGN

Using that cohort, we evaluated EDNRB methylation status and 8 additional genes. Clinical risk assessment by expert clinicians was conducted and compared with biomarker performance in the prediction of premalignant and malignant disease. Methylation status of 9 genes was analyzed in salivary rinses of 191 patients by quantitative methylation-specific PCR.

RESULTS

HOXA9, EDNRB, and deleted in colorectal cancer (DCC) methylation were associated (P = 0.012; P < 0.0001; P = 0.0005) with premalignant or malignant disease. On multivariable modeling, histological diagnosis was only independently associated with EDNRB (P = 0.0003) or DCC (P = 0.004) methylation. A subset of patients received clinical risk classification (CRC) by expert clinicians based on lesion examination. CRC, DCC, and EDNRB were associated with diagnosis of dysplasia/cancer on univariate (P = 0.008; P = 0.026; P = 0.046) and multivariate analysis (P = 0.012; P = 0.037; P = 0.047). CRC identified dysplasia/cancer with 56% of sensitivity and 66% of specificity with a similar area under curve [AUC; 0.61, 95% confidence interval (CI) = 0.60-0.81] when compared to EDNRB and DCC combined AUC (0.60, 95% CI = 0.51-0.69), sensitivity of 46% and specificity of 72%. A combination of EDNRB, DCC, and CRC was optimal AUC (0.67, 95% CI = 0.58-0.76).

CONCLUSIONS

EDNRB and/or DCC methylation in salivary rinses compares well to examination by an expert clinician in CRC of oral lesions. These salivary biomarkers may be particularly useful in oral premalignancy and malignancy screening in clinical care settings in which expert clinicians are not available.

Evaluation of chemiluminescence, toluidine blue and histopathology for detection of high risk oral precancerous lesions: A cross-sectional study

Background

Early detection holds the key to an effective control of cancers in general and of oral cancers in particular. However, screening procedures for oral cancer are not straightforward due to procedural requirements as well as feasibility issues, especially in resource-limited countries.

Methods

We conducted a cross-sectional study to compare the performance of chemiluminescence, toluidine blue and histopathology for detection of high-risk precancerous oral lesions. We evaluated 99 lesions from 55 patients who underwent chemiluminescence and toluidine blue tests along with biopsy and histopathological examination. We studied inter-as well as intra-rater agreement in the histopathological evaluation and then using latent class modeling, we estimated the operating characteristics of these tests in the absence of a reference standard test.

Results

There was a weak inter-rater agreement (kappa < 0.15) as well as a weak intra-rater reproducibility (Pearson's r = 0.28, intra-class correlation rho = 0.03) in the histopathological evaluation of potentially high-risk precancerous lesions. When compared to histopathology, chemiluminescence and toluidine blue retention had a sensitivity of 1.00 and 0.59, respectively and a specificity of 0.01 and 0.79, respectively. However, latent class analysis indicated a low sensitivity (0.37) and high specificity (0.90) of histopathological evaluation. Toluidine blue had a near perfect high sensitivity and specificity for detection of high-risk lesions.

Conclusion

In our study, there was variability in the histopathological evaluation of oral precancerous lesions. Our results indicate that toluidine blue retention test may be better suited than chemiluminescence to detect high-risk oral precancerous lesions in a high-prevalence and low-resource setting like India.

Salivary protein and solCD44 levels as a potential screening tool for early detection of head and neck squamous cell carcinoma

BACKGROUND

Head and neck squamous cell carcinoma (HNSCC) is a devastating disease usually diagnosed at a late stage when cure rates are 40%. We examined a simple and inexpensive molecular tool that may aid HNSCC detection.

METHODS

Building on prior findings that total protein levels are elevated in 102 HNSCC cases versus 84 control subjects, we further analyzed these levels with respect to important risk and demographic variables and compared the results to soluble CD44 (solCD44). Using multivariate adaptive regression splines (MARSs)-logit modeling and logistic regression, we determined whether total protein, solCD44, or the combination best identifies HNSCC.

RESULTS

Combined higher levels of solCD44 and protein were significantly associated with HNSCC (odds ratio [OR] = 24.90; 95% confidence interval [CI], 9.04-68.57; area under the curve [AUC] = 0.786). A model including protein plus solCD44 resulted in a better area (AUC 0.796) than either marker alone.

CONCLUSION

Oral rinse levels of solCD44 and protein seem to hold promise for detection of HNSCC.

The utility of toluidine blue staining and brush cytology as adjuncts in clinical examination of suspicious oral mucosal lesions

The objective of this study was to investigate the utility of toluidine blue and brush cytology in patients with clinically detected oral mucosal lesions. Clinical examination of 35 patients was completed before toluidine blue application, oral brush cytology and scalpel biopsy. Lesions were photographed before and after stain application; followed by brush cytology. All findings were compared with histopathologic results. Severe dysplasia and carcinoma-in-situ were determined as 'positive'; no dysplasia and mild to moderate dysplasia were defined as 'negative'. The sensitivity, specificity, positive and negative predictive values of clinical examination and toluidine blue were the same: 0.923, 0.433, 0.414, and 0.929, respectively. Those of brush cytology were 0.923, 0.517, 0.462, and 0.938. The concordance of all methods was 30% for benign and 61% for malignant lesions. Adjuncts identified 92% of carcinoma-in-situ and squamous cell carcinoma as confirmed by histopathology, in contrast to clinical findings alone in which 62% of these lesions were identified (p=0.046). In conclusion, adjunct diagnostic methods decreased the level of uncertainty for the diagnosis of oral malignancies and lichenoid dysplasias when applied as adjuncts to clinical examination.

Screening programmes for the early detection and prevention of oral cancer

BACKGROUND

Oral cancer is an important global healthcare problem, its incidence is increasing and late-stage presentation is common. Screening programmes have been introduced for a number of major cancers and have proved effective in their early detection. Given the high morbidity and mortality rates associated with oral cancer, there is a need to determine the effectiveness of a screening programme for this disease, either as a targeted, opportunistic or population based measure. Evidence exists from modelled data that a visual oral examination of high-risk individuals may be a cost-effective screening strategy and the development and use of adjunctive aids and biomarkers is becoming increasingly common.

OBJECTIVES

To assess the effectiveness of current screening methods in decreasing oral cancer mortality.

SEARCH STRATEGY

The following electronic databases were searched: the Cochrane Oral Health Group Trials Register (to 20 May 2010), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2010, Issue 2), MEDLINE via OVID (1950 to 20 May 2010), EMBASE via OVID (1980 to 20 May 2010) and CANCERLIT via PubMed (1950 to 20 May 2010). There were no restrictions regarding language or date of publication.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of screening for oral cancer or potentially malignant disorders using visual examination, toluidine blue, fluorescence imaging or brush biopsy.

DATA COLLECTION AND ANALYSIS

The original review identified 1389 citations and this update identified an additional 330 studies, highlighting 1719 studies for consideration. Only one study met the inclusion criteria and validity assessment, data extraction and statistics evaluation were undertaken by six independent review authors.

MAIN RESULTS

One 9-year RCT has been included (n = 13 clusters: 191,873 participants). There was no statistically significant difference in the age-standardised oral cancer mortality rates for the screened group (16.4/100,000 person-years) and the control group (20.7/100,000 person-years). A 43% reduction in mortality was reported between the intervention cohort (29.9/100,000 person-years) and the control arm (45.4/100,000) for high-risk individuals who used tobacco or alcohol or both, which was statistically significant. However, this study had a number of methodological weaknesses and the associated risk of bias was high.

AUTHORS' CONCLUSIONS

Although there is evidence that a visual examination as part of a population based screening programme reduced the mortality rate of oral cancer in high-risk individuals, whilst producing a stage shift and improvement in survival rates across the population as a whole, the evidence is limited to one study and is associated with a high risk of bias. This was compounded by the fact that the effect of cluster randomisation was not accounted for in the analysis. Furthermore, no robust evidence was identified to support the use of other adjunctive technologies like toluidine blue, brush biopsy or fluorescence imaging within a primary care environment. Further randomised controlled trials are recommended to assess the efficacy, effectiveness and cost-effectiveness of a visual examination as part of a population based screening programme.

Potential of optical coherence tomography for early diagnosis of oral malignancies

With nearly 1,500,000 new patients diagnosed every year in the USA, cancer poses a considerable challenge to healthcare today. Oral cancer is responsible for a sizeable portion of deaths due to cancer, primarily because it is diagnosed at a late stage when the prognosis is poor. Current methods for diagnosing oral cancer need to be augmented by better early detection, monitoring and screening modalities. A new approach is needed that provides real-time, accurate, noninvasive diagnosis. The results of early clinical trials using in vivo optical coherence tomography for the diagnosis of oral dysplasia and malignancy are encouraging.

A community-based RCT for oral cancer screening with toluidine blue

Early detection of oral premalignant lesions (OPMLs) by visual inspection with toluidine blue has not been addressed. We conducted a community-based randomized controlled trial to assess whether using toluidine blue as an adjunctive tool for visual screening had a higher detection rate of OPMLs and could further reduce the incidence of oral cancer. In 2000, in Keelung, we randomly assigned a total of 7975 individuals, aged 15 years or older and with high-risk oral habits, to either the toluidine-blue-screened (TBS) group or the visual screening group. Results showed 5% more oral premalignant lesions and 79% more oral submucous fibrosis detected in the TBS group than in the control group. After a five-year follow-up ascertaining oral cancer development through linkage to the National Cancer Registry, the incidence rate in the TBS group (28.0 x 10(-5)) was non-significantly 21% lower than that in the control group (35.4 x 10(-5)).

Toluidine blue color perception in identification of oral mucosal lesions

The objective of this study is to examine observer agreement on the rank of the color tones after toluidine blue staining of a mucosal lesion. Cohort study with repeated measures is the design of the study. Twenty observers ranked and scored 8 specified areas on the color images of a lesion before and after toluidine blue application in two sessions. Inter and intra-observer variations were analyzed with Cohen's kappa. The L* (the black-white axis), a* (red-green axis), and b* (yellow-blue axis) values were measured and set as the gold standards. Intra and inter-observer agreements were к = 0.86 and к = 0.854. All color parameters were effective on the color ranking order (pL* = 0.00, pa* = 0.007, pb* = 0.00), although L* and b* were more effective on the ranking of the samples than a*. Areas that appeared pale blue visually had a significant blue component, but the observers were confused with the effect of whiteness of the area in clinical decision making.

In vivo diagnosis of oral dysplasia and malignancy using optical coherence tomography: preliminary studies in 50 patients

BACKGROUND

In vivo, non-invasive optical coherence tomography (OCT) permits high-resolution imaging of tissue surfaces and subsurfaces, with the potential capability for detection and mapping of epithelial pathologies.

PURPOSE

To evaluate the clinical capability of non-invasive in vivo OCT for diagnosing oral dysplasia and malignancy.

EXPERIMENTAL DESIGN

In 50 patients with oral lesions, conventional clinical examination was followed by OCT imaging, then standard biopsy and histopathology. Two blinded, pre-standardized investigators separately diagnosed each lesion based on (1) OCT and (2) histopathology.

RESULTS

Intra- and inter-observer agreement between diagnoses based on histopathology and imaging data was excellent, with lambda values between 0.844 and 0.896. Sensitivity and specificity were also very good.

CONCLUSIONS

These data demonstrate the excellent capability of in vivo OCT for detecting and diagnosing oral premalignancy and malignancy in human subjects.

The adjunctive role of toluidine blue in detection of oral premalignant and malignant lesions

PURPOSE OF REVIEW

To review the literature on toluidine blue (TBlue) and to discuss the utility of TBlue in assessing and in clinical management of patients with oral mucosal lesions. The literature search was conducted using key word search including oral cancer, oral premalignant lesions, and TBlue and by selecting references from the articles reviewed.

RECENT FINDINGS

The findings of this review show that TBlue has utility as an adjunct in the detection of premalignant and malignant oral mucosal lesions and in identifying high-risk areas of lesions for biopsy in patients at increased risk of cancer when evaluated by experienced healthcare workers.

SUMMARY

TBlue positive lesions, whether histologically benign or with dysplasia, predict molecular change and behavior of oral premalignant lesions. TBlue may provide information regarding lesion margins, accelerate the decision to biopsy, guide biopsy site selection and treatment of oral premalignant and malignant lesions. These findings support the utility of TBlue as a clinical adjunct in assessment of oral mucosal lesions.

Exploring the reasons for delay in treatment of oral cancer

BACKGROUND

Oral cancer continues to be diagnosed and treated at a late stage, which has a negative effect on outcomes. This study identified and quantified delays in diagnosis and treatment.

METHODS

The authors conducted a study that included all new patients seen in the Department of Oral and Maxillofacial Surgery, University of California, San Francisco, between 2003 and 2007 who had a diagnosis of squamous cell carcinoma of the oral cavity. They identified the time intervals for six stages, beginning with the time at which patients first became aware of symptoms and ending with the time at which definitive treatment began.

RESULTS

The total time from patients' first sign or symptoms to commencement of treatment was a mean of 205.9 days (range, 52-786 days). The longest delay was from the time symptoms first appeared to the initial visit to a health care professional (mean time, 104.7 days; range, 0-730 days).

CONCLUSIONS

Health care professionals need to place greater emphasis on patient education to encourage early self-referrals.

CLINICAL IMPLICATIONS

Patients should be encouraged to visit a health care professional when signs or symptoms of oral cancer first develop.

Adjunctive techniques for oral cancer examination and lesion diagnosis: a systematic review of the literature

BACKGROUND

Adjunctive techniques that may facilitate the early detection of oral premalignant and malignant lesions (OPML) have emerged in the past decades.

METHODS

The authors undertook a systematic review of the English-language literature to evaluate the effectiveness of toluidine blue (TB), ViziLite Plus with TBlue (Zila Pharmaceuticals, Phoenix), ViziLite (Zila Pharmaceuticals), Microlux DL (AdDent, Danbury, Conn.), Orascoptic DK (Orascoptic, a Kerr Company, Middleton, Wis.), VELscope (LED Dental, White Rock, British Columbia, Canada) and OralCDx (Oral CDx Laboratories, Suffern, N.Y.) brush biopsy. They abstracted data relating to study design, sampling and characteristics of the study group, interventions, reported outcomes and diagnostic accuracy of adjunctive aids from 23 articles meeting inclusion and exclusion criteria, including availability of histologic outcomes.

RESULTS

The largest evidence base was for TB. A limited number of studies was available for ViziLite, ViziLite Plus with TBlue and OralCDx. Studies of VELscope have been conducted primarily to assess the margins of lesions in known OPML. The authors identified no studies of Microlux DL or Orascoptic DK. Study designs had various limitations in applicability to the general practice setting, including use of higher-risk populations and expert examiners.

CONCLUSIONS

There is evidence that TB is effective as a diagnostic adjunct for use in high-risk populations and suspicious mucosal lesions. OralCDx is useful in assessment of dysplastic changes in clinically suspicious lesions; however, there are insufficient data meeting the inclusion criteria to assess usefulness in innocuous mucosal lesions. Overall, there is insufficient evidence to support or refute the use of visually based examination adjuncts. Practical Implications. Given the lack of data on the effectiveness of adjunctive cancer detection techniques in general dental practice settings, clinicians must rely on a thorough oral mucosal examination supported by specialty referral and/or tissue biopsy for OPML diagnosis.

Soluble CD44 is a potential marker for the early detection of head and neck cancer

INTRODUCTION

Head and neck squamous cell carcinoma (HNSCC) is a devastating and deadly disease, largely because it is diagnosed in late stage. Cure rates, currently at 50%, could increase to >80% with early detection. In this study, we evaluate soluble CD44 (solCD44) as an early detection tool for HNSCC by determining whether it reliably distinguishes HNSCC from benign disease of the upper aerodigestive tract.

METHODS

We carried out the solCD44 ELISA on oral rinses from 102 patients with HNSCC and 69 control patients with benign diseases of upper aerodigestive tract to determine the sensitivity and specificity of the test for differentiating HNSCC from benign disease. Furthermore, we did a pilot study using methylation-specific PCR primers on oral rinses from 11 HNSCC patients with low solCD44 levels and 10 benign disease controls.

RESULTS

Mean salivary solCD44 levels were 24.4 +/- 32.0 ng/mL for HNSCC patients (range, 0.99-201 ng/mL) and 9.9 +/- 16.1 ng/mL (range, 0.73-124 ng/mL) for the patients with benign disease (P < 0.0001). Depending on cutoff point and HNSCC site, sensitivity ranged from 62% to 70% and specificity ranged from 75% to 88%. Nine of 11 HNSCC and 0 of 10 controls with low solCD44 levels showed hypermethylation of the CD44 promoter.

CONCLUSIONS

SolCD44 is elevated in the majority of HNSCC and distinguishes cancer from benign disease with high specificity. Whereas the solCD44 test lacks sensitivity by itself, methylation status of the CD44 gene seems to complement the solCD44 test. Our pilot data indicate that, together, these markers will detect HNSCC with very high sensitivity and specificity.

Rose bengal staining in detection of oral precancerous and malignant lesions with colorimetric evaluation: a pilot study

Early detection of oral precancerous and malignant lesions is still a diagnostic challenge for most of clinicians, and ideal adjuncts for detection of these lesions are currently unavailable. Our preliminary study has indicated that rose bengal (RB) staining might have the potency as a diagnostic aid; however, its clinical significance and reliability in hospital-based population are still not clear. In the present study, we investigated the efficacy of RB staining in detection of oral precancerous and malignant lesions. RB staining was conducted in 132 patients, and staining results were determined by a 4-graded shade guide, which had been quantitatively measured in the 1976 CIEL*a*b* space by instrumental colorimetry. Histological examination was performed in 128 of 132 patients after RB staining. The sensitivity and specificity to detect epithelial dysplasia (DP) and oral squamous cell carcinoma were 93.9 and 73.7%, respectively. The positive and negative likelihood ratios were 3.570 and 0.082, respectively. Moreover, RB staining seemed promising to detect DP in oral leukoplakia, lichen planus and leukokeratosis. In this study, 5 of 6 DP or oral squamous cell carcinoma were identified by RB staining before histological examination. In conclusion, RB staining may be a valuable diagnostic test in detection of oral precancerous and malignant lesions.

Optical pathology using oral tissue fluorescence spectra: classification by principal component analysis and k-means nearest neighbor analysis

The spectral analysis and classification for discrimination of pulsed laser-induced autofluorescence spectra of pathologically certified normal, premalignant, and malignant oral tissues recorded at a 325-nm excitation are carried out using MATLAB@R6-based principal component analysis (PCA) and k-means nearest neighbor (k-NN) analysis separately on the same set of spectral data. Six features such as mean, median, maximum intensity, energy, spectral residuals, and standard deviation are extracted from each spectrum of the 60 training samples (spectra) belonging to the normal, premalignant, and malignant groups and they are used to perform PCA on the reference database. Standard calibration models of normal, premalignant, and malignant samples are made using cluster analysis. We show that a feature vector of length 6 could be reduced to three components using the PCA technique. After performing PCA on the feature space, the first three principal component (PC) scores, which contain all the diagnostic information, are retained and the remaining scores containing only noise are discarded. The new feature space is thus constructed using three PC scores only and is used as input database for the k-NN classification. Using this transformed feature space, the centroids for normal, premalignant, and malignant samples are computed and the efficient classification for different classes of oral samples is achieved. A performance evaluation of k-NN classification results is made by calculating the statistical parameters specificity, sensitivity, and accuracy and they are found to be 100, 94.5, and 96.17%, respectively.

The efficacy of oral lumenoscopy (ViziLite) in visualizing oral mucosal lesions

Early diagnosis of oral mucosal lesions has been advocated as a means of improving outcomes of cancer therapy. Improved visualization of mucosal lesions may aid in diagnosis by guiding tissue sampling or referral. This multicenter study reports the effect of chemiluminescent light (ViziLite) upon visualization of mucosal lesions. The chemiluminescent light did not appear to improve visualization of red lesions, but white lesions and lesions that were both red and white showed enhanced brightness and sharpness.

Oral cancer knowledge and awareness: primary and secondary effects of an information leaflet

Information leaflets can be stored and read several times at the patient's own convenience and speed and, therefore, might contribute to increasing the long-term oral cancer knowledge and awareness. This hypothesis was investigated in a sample of adults living in a small central Italian town. The two groups of patients selected (Intervention, 100 subjects; Control, 84 subjects) were all aged 40 years and had never received oral cancer counselling or examination previously. Subjects completed a questionnaire (PRE) containing items regarding oral cancer epidemiology and prevention. Thereafter, the Intervention patients received the oral cancer information leaflet. One year later, patients from both groups were re-contacted and most (97 Intervention, 79 Control subjects, overall participation rate, 95.7%) completed the same questionnaire (POST). The POST questionnaire score, the score increment and the proportion of patients who sought an oral cancer examination during the year follow-up were used as markers of long-term knowledge, knowledge improvement and awareness, respectively. The between group differences in mean PRE score, POST score, score increment and proportion of subjects who had an examination were assessed by conventional statistical tests. The effect of leaflet corrected for confounders also was assessed using multiple regression analyses. No difference in PRE score and awareness was found. However, the mean POST score and the score increment were significantly higher in the Intervention group. The leaflet significantly increased knowledge but not awareness, with statistically significant effects from high educational level and younger age. It is concluded that the information leaflet had a significant effect in raising the long-term oral cancer knowledge in the general public. It also had a secondary effect on disease awareness in the locale.

A reason for the use of toluidine blue staining in the presurgical management of patients with oral squamous cell carcinomas

Verification of oral cancer relies on histopathological diagnosis of suspect or malignant lesions. There is evidence for further pre-surgical screening procedures to localize tumor borders and define other malignant lesions. Important methods are: visual examination, including pan-endoscopy, fluorescence imaging, and brush biopsy, as well as radiologic techniques such as conventional radiography, computed tomography, magnetic resonance imaging, scintigraphy, and ultrasonography, which may reduce the mortality rate associated with oral cancer. In addition, toluidine blue staining is a simple, inexpensive, and excellent diagnostic tool. Herein we show that the clinical use of in vivo staining is effective to define the superficial tumor borders and to detect malignant or pre-malignant cells in the surrounding area of the tumor following detection of a malignancy of the oral cavity. In our reported case, the main tumor mass was surrounded by layers of an intact mucosa, yet in a distance of more than 1 cm a group of malignant or pre-malignant cells in the surrounding area required a resection of the tumor in a size that would have been unaddressed during visual examination alone followed by clinical routine program of presurgical examinations after the detection of a malignancy of the oral cavity.

Screening programmes for the early detection and prevention of oral cancer

BACKGROUND

Screening programmes for major cancers, such as breast and cervical cancer have effectively decreased the mortality rate and helped to reduce the incidence of these cancers. Although oral cancer is a global health problem with increasing incidence and mortality rates, no national population-based screening programmes for oral cancer have been implemented. To date there is debate on whether to employ screening methods for oral cancer in the daily routine work of health providers.

OBJECTIVES

To assess the effectiveness of current screening methods in decreasing oral cancer mortality.

SEARCH STRATEGY

Electronic databases (MEDLINE, CANCERLIT, EMBASE, the Cochrane Central Register of Controlled Trials; 1966 to July 2005, The Cochrane Library - Issue 3, 2005), bibliographies, handsearching of specific journals and contact authors were used to identify published and unpublished data.

SELECTION CRITERIA

Randomised controlled trials of screening for oral cancer or precursor oral lesions using visual examination, toluidine blue, fluorescence imaging or brush biopsy.

DATA COLLECTION AND ANALYSIS

The search found 112 citations and these have been reviewed. One randomised controlled trial of screening strategies for oral cancer was identified as meeting the review's inclusion criteria. Validity assessment, data extraction and statistics evaluation were undertaken by two independent review authors.

MAIN RESULTS

One 10-year randomised controlled trial has been included (n = 13 clusters: 191,873 participants). There was no difference in the age-standardised oral cancer mortality rates for the screened group (16.4/100,000 person-years) and the control group (20.7/100,000 person-years). Interestingly, a significant 34% reduction in mortality was recorded in high-risk subjects between the intervention cohort (29.9/100,000 person-years) and the control arm (45.4/100,000). However, this study has some methodological weaknesses. Additionally, the study did not provide any information related to costs, quality of life or even harms of screening from false-positive or false-negative findings.

AUTHORS' CONCLUSIONS

Given the limitation of evidence (only one included randomised controlled trial) and the potential methodological weakness of the included study, it is valid to say that there is insufficient evidence to support or refute the use of a visual examination as a method of screening for oral cancer using a visual examination in the general population. Furthermore, no robust evidence exists to suggest that other methods of screening, toluidine blue, fluorescence imaging or brush biopsy, are either beneficial or harmful. Future high quality studies to assess the efficacy, effectiveness and costs of screening are required for the best use of public health resources. In addition, studies to elucidate the natural history of oral cancer, prevention methods and the effectiveness of opportunistic screening in high risk groups are needed. Future studies on improved treatment modalities for oral cancer and precancer are also required.

Knowledge of oral cancer risk factors and diagnostic concepts among North Carolina dentists

BACKGROUND

Dentists play a critical role in the early detection of oral and pharyngeal cancer (OPC). The authors administered a survey that assessed the level of knowledge among dentists regarding risk factors and diagnostic concepts.

METHODS

In 2002, the authors mailed a 38-item, pretested survey to a random sample of 1,115 licensed dentists practicing in North Carolina. Three-level (low, medium, high) composite index scores for knowledge of risk factors and diagnostic concepts were created using previously developed scales. The authors formulated multivariable models for risk factor and diagnostic knowledge indexes.

RESULTS

Of the 584 respondents, only 181 (31 percent) had consistent medium-to-high levels of knowledge on both highly correlated indexes. Dentists who had higher risk factor and diagnostic knowledge scores were significantly (P < .05) more likely to have heard of one or more diagnostic aids (odds ratio [OR], 2.7), to have graduated from dental school within the previous 20 years (OR, 1.8) and to have performed biopsies or referred five or more patients with suspicious lesions per year (OR, 1.7 and 1.5, respectively) than were less-knowledgeable respondents.

CONCLUSIONS

More education is needed in dental schools, postgraduate programs and continuing education programs to enhance dental professionals' knowledge of OPC risk factors and diagnostic concepts. Such programs should include information about adjunctive diagnostic aids.

PRACTICE IMPLICATIONS

Greater knowledge of risk factors and diagnostic concepts may result in more frequent patient referrals, biopsy procedures or both, thus aiding in the early diagnosis and treatment of patients with OPC.

Molecular Detection of Early-Stage Laryngopharyngeal Squamous Cell Carcinomas

PURPOSE

We sought to determine whether early-stage laryngopharyngeal squamous cell carcinomas (SCC) can be detected through molecular analysis of exfoliated cells collected with the use of a pharyngoesophageal brush (PEB).

EXPERIMENTAL DESIGN

Thirty-three patients with a single, untreated, early-stage (T1 or T2) SCC of the supraglottic larynx or pharynx underwent collection of cells with a PEB, followed by endoscopic biopsy of the tumor. PEB specimens were also collected from five healthy subjects. PEB samples and tumor tissue were examined for hypermethylation of p16INK4a (CDKN2) gene promoter CpG islands (assayed by methylation-specific PCR) and UT5085 tetranucleotide microsatellite instability (assayed by GeneScan analysis). PEB samples were also subjected to cytologic analysis.

RESULTS

Eight of 33 (24%) tumors exhibited a bandshift at UT5085, and 14 of 33 (42%) exhibited hypermethylation at the p16 promoter. Overall, 17 of 33 (52%) patients had at least one of the two markers in their tumor. Cytologic analysis of PEB samples revealed tumor in 4 of 33 (12%) patients; cytologic findings were normal in all five control subjects. Molecular analysis of PEB samples revealed tumor DNA in 13 of 17 (76%) patients with at least one of the two molecular markers in their tumor. Eight of 14 (57%) patients with p16 hypermethylation in their tumor and 8 of 8 (100%) patients with UT5085 microsatellite instability in their tumor had similar findings in the PEB samples. None of the PEB samples from the control subjects or patients with neither molecular marker in their tumor displayed abnormality.

CONCLUSION

Molecular analysis of PEB samples holds promise for the early detection of early-stage laryngopharyngeal SCCs. New molecular markers need to be identified to increase the sensitivity of molecular screening.

Salivary Soluble CD44: A Potential Molecular Marker for Head and Neck Cancer

OBJECTIVE

Head and neck squamous cell carcinoma (HNSCC) is a debilitating disease which is cured only 50% of the time. If diagnosed early, survival rates could reach 80%, but there is currently no practical method for early detection. CD44 comprises a family of isoforms that, in certain tumors, are alternatively spliced and overexpressed in tissues and circulation. Here we examine salivary soluble CD44 (solCD44) expression in HNSCC patients and normal controls to determine its potential as a screening tool.

METHOD

We did a solCD44 ELISA on saliva from 26 HNSCC patients, 10 normal volunteers, conditioned media (CM) of 4 HNSCC cell lines, and 1 CD44-negative cell line (COS-7). Western blot was done on CM from 2 HNSCC cell lines (UMSS11B and FaDu), COS-7, 3 HNSCC, and 2 normal saliva specimens to verify ELISA antibody specificity. SolCD44 levels were significantly elevated in HNSCC patients compared with normal controls (7.85 ng/mL for HNSCC patients and 1.09 ng/mL for normal controls, P < 0.001).

RESULTS

The test detected 79% of mucosally invasive HNSCC using preliminary cutoff points. SolCD44 levels did not vary significantly with tumor size, stage, recurrence, history of radiation treatment, or tobacco and alcohol risk factors. A 65 to 75 kDa band, corresponding to solCD44, was detected in all of the HNSCC cell line CM and saliva whereas normal samples showed a fainter band or were undetectable.

CONCLUSION

In this preliminary analysis, the salivary solCD44 ELISA seems to effectively detect HNSCC at all stages. Further study is indicated because early detection is clearly important in this disease.

Criteria to rationalize population screening to control oral cancer

Screening populations for the early detection of asymptomatic malignancies and potential malignancies are intuitively attractive strategies to control or reduce the burden of oral cancer on society. Subsequent preventive and/or therapeutic measures must, however, be substantiated by prospective randomized controlled trials (RCT) to markedly improve patient outcomes to reconcile such usages of 'scarce' healthcare resources. This strategic objective is more likely to be achieved by adopting the precedent established by cardiology, where prevention is emphasized over the treatment of occult lesions. For example, the screening identification of individuals at high oral carcinogenic risk will offer potential educational opportunities to change their behaviors, and/or optimize the implementation of contemporary preventive and therapeutic measures for non-compliant individuals. The imperative to substantiate the effectiveness of the screening assays (tests) by prospective RCT also cannot be ignored to safeguard the public against potential false-negative or false-positive diagnoses.