Computer-assisted analysis of oral brush biopsies at an oral cancer screening program

Abrasive cytohistology of squamous epithelial lesions

Objective:

To describe a method to retrieve cellular and tissue elements of oral squamous epithelium obtained by abrasive methods and to conduct investigations by cytohistology.

Method:

We developed a special gelatine pocket suitable for paraffin embedding of sparse material obtained from brush biopsies (BBs). This was subjected to combined evaluation of a cytological (smear) and histological examination of the ‘tissue sections’ – referred as cytohistology. Four diagnostic categories were applied for evaluation. Other special diagnostic methods were also applied in addition to recording dysplasia.

Results:

A total of 51, 755 BBs from suspicious lesions of the oral mucosa (mostly oral potentially malignant disorders – OPMD) were evaluated for the presence of carcinoma or dysplasia; in all, 1.7% were positive, 78.2% were negative for any epithelial atypia, 16.8% atypical and 3.3% inadequate. All BBs also had cytohistological evaluation. A ‘positive’ diagnosis by cytohistology was a reliable indicator of dysplasia or carcinoma, requiring further incisional/excisional biopsy. In the ‘atypical’ category, a variety of lesions were found, about half being dysplasia or carcinoma. This category challenges the clinician for further clinical, therapeutic and/or excisional examination. In ‘negative’ cases with persistence of the lesion, a re-examination in 1-year sequence is recommended.

Conclusion:

Cytohistology of material derived by abrasive methods allows earlier detection of dysplasia/carcinoma. A number of additional oncological and non-oncological findings make this method a valuable non-invasive diagnostic procedure for oral mucosal lesions.

Adjunctive aids for the detection of oral premalignancy

Early detection of cancer greatly decreases the morbidity and mortality rates and thereby increases the 5-year survival rates. In developing countries like India where the disease is highly prevalent focus is mainly on decreasing the mortality rates which can be easily achieved by detection at an asymptomatic stage. Visual examination has been the standard screening method for screening oral cancer through several decades, and it is well known that conventional visual examination is limited to subjective interpretation and cannot be easily achieved in certain anatomical sites. As a solution to all these adjunctive techniques have emerged, and it has been widely used. An effort is made through this paper to review the most commonly used adjunctive aids for the detection of premalignancy and cancer.

Clinical and cytological study of the oral mucosa of smoking and non-smoking qat chewers in Yemen

OBJECTIVE

The study was conducted to investigate the role of qat and smoking habits on the prevalence of visible and cytological abnormalities in the oral mucosa among Yemenites.

METHODS

We recruited 30 non-smoking and 30 smoking Yemenites chewing qat unilaterally for at least 5 years. We inspected oral cavities for the presence of lesions and took brush biopsies from the buccal mucosa/gingiva of the chewing/non-chewing region.

RESULTS

All visible oral lesions were flat and homogeneous, and cytological changes were detected frequently. Among both non-smokers and smokers, white lesions and cytological changes were detected in 77% of all cases. On the chewing area, the proportion with white lesions ranged--depending on anatomical area and smoking status--between 47 and 93% and was significantly more frequent than on the non-chewing side (range 3-47%). The proportion of regions with changes was similar in non-smokers and smokers. Kappa statistics for "interobserver" agreement between visual inspection and cytological specimens of brush biopsies was at best fair (≤0.25).

CONCLUSIONS

The high prevalence of visible lesions and cytological abnormalities among qat chewers was independent of smoking status.

CLINICAL RELEVANCE

The moderate level of agreement between visual inspection and exfoliative cytology demonstrates the still challenging clinical management of chronic qat chewers, though brush biopsies including adjuvant techniques like DNA cytometry may support the clinical decision-making process in future.

Cancer Screening: Should Cancer Screening be Essential Component of Primary Health Care in Developing Countries?

Background:

Cancer is a fatal disease and is on the rise across the globe. In India, breast, cervix and the oral cavity are the leading cancer sites, but, unfortunately, in-spite of availability of screening tools, there is no organized cancer screening program in India. The main objective of this study was to review the performance of various cancer screening modalities in a resource poor setting.

Methods:

MEDLINE and web of science electronic database was searched from January 1990 to December 2013, using keywords such as “breast cancer, cervical cancer, oral cancer and their corresponding mesh terms were also used in combination with Boolean operators OR, AND.” Two authors independently selected studies published in English and conducted in India. A total of 16 studies was found relevant and eligible for the review. The data on sensitivity and specificity of various screening tool was extracted and analyzed.

Results:

Most of the reported screening trails in India are on cervical cancer and few on breast and oral cancer screening. The pooled estimates of sensitivity and specificity of cervical cancer screening test such as visual inspection with acetic acid, magnified visual inspection with acetic acid, visual inspection with Lugol's iodine, cytology (Papanicolaou smear) and human papillomavirus deoxyribonucleic acid was found to be 68.76% and 84.02%, 63.27% and 85.43%, 81.86% and 87.03%, 63.25% and 93.17% and 75.04% and 91.66%, respectively. Sensitivity and specificity of clinical breast examination was found to be 94.30% and 94.30%, respectively. Oral cancer screening through visual inspection by trained health care worker was found to have 87.90% sensitivity and 92.05% specificity.

Conclusions:

Our study highlights the availability and success of visual screening tools in early detection and mortality reduction of major neoplasia in resource-poor health care settings and recommends implementation of oral and cervical cancer screening as part of assured primary health care package in developing countries.

Prediction using hierarchical data: Applications for automated detection of cervical cancer

Although the Papanicolaou smear has been successful in decreasing cervical cancer incidence in the developed world, there exist many challenges for implementation in the developing world. Quantitative cytology, a semi-automated method that quantifies cellular image features, is a promising screening test candidate. The nested structure of its data (measurements of multiple cells within a patient) provides challenges to the usual classification problem. Here we perform a comparative study of three main approaches for problems with this general data structure: a) extract patient-level features from the cell-level data; b) use a statistical model that accounts for the hierarchical data structure; and c) classify at the cellular level and use an ad hoc approach to classify at the patient level. We apply these methods to a dataset of 1,728 patients, with an average of 2,600 cells collected per patient and 133 features measured per cell, predicting whether a patient had a positive biopsy result. The best approach we found was to classify at the cellular level and count the number of cells that had a posterior probability greater than a threshold value, with estimated 61% sensitivity and 89% specificity on independent data. Recent statistical learning developments allowed us to achieve high accuracy.

Transepithelial Brush Biopsy - Oral CDx® - A Noninvasive Method for the Early Detection of Precancerous and Cancerous Lesions

INTRODUCTION

The Oral CDx® brush biopsy (BB) method is a computer-assisted sample analysis that detects abnormal cells in all cell layers of the epithelium of the oral mucosa.

METHOD

We took 263 oral BBs from 200 patients with potentially malignant disorders.

RESULTS

We received 204 negative results and 39 atypical, 7 positive and 13 inadequate results. SBs were taken in 56 cases. Therefore, the sensitivity for the detection of abnormal cells was 90% and the specificity was 44.1%. The positive predictive value accounted for 47.2% and the NPV accounted for 88.2%.

DISCUSSION AND CONCLUSION

For the results of sensitivity and specificity of the Oral CDx® BB, there is still space for improvement but they are already high. Additional methods like DNA-image cytometry may enhance the results. But it is a simple and noninvasive method which does not need a special effort either from the patient or from the clinicians.

Human Calmodulin-Like Protein CALML3: A Novel Marker for Normal Oral Squamous Mucosa That Is Downregulated in Malignant Transformation

Oral cancer is often diagnosed only at advanced stages due to a lack of reliable disease markers. The purpose of this study was to determine if the epithelial-specific human calmodulin-like protein (CALML3) could be used as marker for the various phases of oral tumor progression. Immunohistochemical analysis using an affinity-purified CALML3 antibody was performed on biopsy-confirmed oral tissue samples representing these phases. A total of 90 tissue specimens were derived from 52 patients. Each specimen was analyzed in the superficial and basal mucosal cell layers for overall staining and staining of cellular subcompartments. CALML3 was strongly expressed in benign oral mucosal cells with downregulation of expression as squamous cells progress to invasive carcinoma. Based on the Cochran-Armitage test for trend, expression in the nucleus and at the cytoplasmic membrane significantly decreased with increasing disease severity. Chi-square test showed that benign tissue specimens had significantly more expression compared to dysplasia/CIS and invasive specimens. Dysplasia/CIS tissue had significantly more expression than invasive tissue. We conclude that CALML3 is expressed in benign oral mucosal cells with a statistically significant trend in downregulation as tumorigenesis occurs. CALML3 may thus be a sensitive new marker for oral cancer screening.

An evaluation of the Shandon Papspin liquid-based oral test using a novel cytologic scoring system

OBJECTIVES

The aim of this study was to evaluate a cost-effective oral liquid-based cytology screening test, Shandon Papspin (PS).

STUDY DESIGN

We compared the diagnostic accuracy of PS with surgical biopsy in 69 patients. Transepithelial cytology specimens were obtained with the use of cervical cytobrushes. Cytology specimens were graded and scored by using a novel oral cytologic grading and scoring system.

RESULTS

Histologic diagnosis of dysplasia or malignancy was made in 51/69 cases, and cytology identified 49/51 cases, with a sensitivity of 96% and specificity of 100%. The best cutoff value for distinguishing reactive/mildly dysplastic lesions from high grade/invasive squamous cell carcinoma was determined to be a cytologic score of 3, representing a sensitivity of 95% and specificity of 96%.

CONCLUSIONS

PS appears to be an accurate and economical test for detection of high-risk dysplasias and cancers, but the real significance of this method will be its diagnostic accuracy in studies focusing strictly on lesions with a low level of clinical concern.

The sensitivity and specificity of computerized brush biopsy and scalpel biopsy in diagnosing oral premalignant lesions: A comparative study

Background:

The diagnosis of oral malignancy and epithelial dysplasia has traditionally been based upon histopathological evaluation of full thickness biopsy from lesional tissue. As many studies had shown that incisional biopsy could cause progression of the tumors, many alternative methods of collection of samples had been tested. Oral brush biopsy is a transepithelial biopsy where it collects cells from basal cell layer noninvasively.

Aim:

To assess the diagnostic accuracy of brush biopsy when compared to histopathology in a group of patients with features of potentially malignancy.

Materials and Methods:

In the present study, 60 cases of clinically diagnosed leukoplakia are selected and subjected to histopathology and brush biopsy.

Results and Conclusion:

Results showed that of 16 dysplasia cases confirmed by histopathology, only 12 were positively reported in oral brush biopsy. In 44 cases, the reports are same for histopathology and brush biopsy. The sensitivity of oral brush biopsy is 43.5% and specificity is 81.25% with a positive predictive value of 58.3%. Oral brush biopsy with molecular markers like tenascin and keratins can be an accurate diagnostic test.

Applications of OralCDx® methodology in the diagnosis of oral leukoplakia

Objective: We aim to evaluate the effectiveness of the brush biopsy technique using OralCDx ® (OralScan Laboratories Inc., Suffern, NY) as a new method for early diagnosis and control of a “potentially malignant disorder” such as oral leukoplakia. Design of the study: We performed a study in which samples were taken using OralCDx ® on 24 patients who visited the Master of Oral Medicine, Oral Surgery and Implantology of the University of Santiago de Compostela between February 2009 and May 2010. These patients presented clinical and histological lesions that were consistent with oral leukoplakia. We evaluated the relationship between the keratinization degree of the lesions and cell representation; the diagnosis obtained through OralCDx ® and biopsies; and sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV). Results: 50% of patients were men and 50% women with an average age of 62.38 years. The Kappa coefficient relating keratinization of lesions and cell representation was 0.33, the OralCDx ® - biopsy diagnostic rate reached a Kappa value of 0.66, recording 72.7%,sensitivity and 92.3% specificity, PPV was 88.8%, while NPV reached 80%. Conclusions: cytology sampling with OralCDx ® showed high sensitivity and specificity values, which make it a good tool for monitoring oral leukoplakia, but nowadays the most reliable method that allows us to confirm the exact diagnosis of the lesions and their anatomical and pathological characteristics still is conventional biopsy using a surgical scalpel.

Key words: OralCDx®, brush biopsy, oral leukoplakia.

Early detection of oral cancer: PAP and AgNOR staining in brush biopsies

Aim:

The aim of this study was to determine the diagnostic accuracy of routine Papanicolaou stain (PAP) and Silver stained Nucleolar Organizer Regions (AgNOR) staining in brush biopsies taken from suspected oral lesions for early detection of oral cancer.

Materials and Methods:

Brush biopsies were collected from macroscopically suspicious lesions of the oral cavity of 34 patients and 10 normal-aged and sex-matched controls. The numbers of AgNORs were counted in 100 squamous epithelial cell nuclei per slide after silver staining of the smears (Ploton’s one-step method).

Results:

Sensitivity and specificity of PAP analysis in the oral smears for detection of oral cancer and normal cells was 91.176% and 100%. The positive and negative prediction values were 100% and 76.92%, respectively. Sensitivity and specificity of AgNOR analysis in the oral smears for detection of oral cancer and normal cells was 100%. The positive and negative prediction values were 100% each.

Conclusion:

Based on the above facts, we conclude that brush biopsy in conjunction with AgNOR staining is an easily practicable, non-invasive, safe and accurate screening method for the detection of macroscopically suspicious oral cancerous lesions. Because of its simple technique and high reliability for cellular proliferation, AgNOR staining in brush smears can be used as an adjunct to other routine cytological diagnoses for the early detection of oral cancer. However, further investigations with more number of study samples will be needed to establish this correlation beyond doubt.

Classifying tissue samples from measurements on cells with within-class tissue sample heterogeneity

We consider here the problem of classifying a macro-level object based on measurements of embedded (micro-level) observations within each object, for example, classifying a patient based on measurements on a collection of a random number of their cells. Classification problems with this hierarchical, nested structure have not received the same statistical understanding as the general classification problem. Some heuristic approaches have been developed and a few authors have proposed formal statistical models. We focus on the problem where heterogeneity exists between the macro-level objects within a class. We propose a model-based statistical methodology that models the log-odds of the macro-level object belonging to a class using a latent-class variable model to account for this heterogeneity. The latent classes are estimated by clustering the macro-level object density estimates. We apply this method to the detection of patients with cervical neoplasia based on quantitative cytology measurements on cells in a Papanicolaou smear. Quantitative cytology is much cheaper and potentially can take less time than the current standard of care. The results show that the automated quantitative cytology using the proposed method is roughly equivalent to clinical cytopathology and shows significant improvement over a statistical model that does not account for the heterogeneity of the data.

Techniques for precancerous lesion diagnosis

The development of the oral squamous cell carcinoma (OSCC) is a multistep process that requires the accumulation of multiple genetic alterations usually preceded by detectable mucosal changes, most often leukoplakias and erythroplakias. The clinical appearance of oral precancerous lesions and their degree of epithelium dysplasia suggests the malignization potential. Several techniques have been developed to improve the clinical and cytological diagnosis of oral precancerous lesions. The present paper reviews the main techniques used to improve premalignant lesion diagnosis.

Effectiveness of oral surgeons compared with OralCDx brush biopsy in diagnosing oral dysplastic lesions

PURPOSE

To evaluate oral surgeons' effectiveness in diagnosing oral dysplastic lesions and compare it to OralCDx brush biopsy.

MATERIALS AND METHODS

In this cross-sectional study, the oral surgeon's ability to diagnose dysplasia among 152 consecutive cases (tissue samples) that had previously tested either "positive" (n = 3) or "atypical" (n = 149) for dysplasia by OralCDx brush biopsy was determined by calculating sensitivity, specificity, positive predictive value (PPV), and negative predictive value using the scalpel biopsy as the gold standard. PPV for oral surgeons and atypical brush biopsy was compared stratified by age, gender, and lesion site.

RESULTS

The PPV, negative predictive value, sensitivity, and specificity for oral surgeons were 10.3%, 100%, 100%, and 23.5%, respectively. After controlling for age, gender, and lesion site, oral surgeons were 19% to 58% more likely to diagnose a dysplastic lesion compared to OralCDx brush biopsy.

CONCLUSIONS

Oral surgeons' effectiveness in diagnosing oral dysplastic lesions was slightly better than the OralCDx brush biopsy; hence, it is recommended that patients be referred to an oral surgeon for evaluation.

Salivary markers for oral cancer detection

Oral cancer refers to all malignancies that arise in the oral cavity, lips and pharynx, with 90% of all oral cancers being oral squamous cell carcinoma. Despite the recent treatment advances, oral cancer is reported as having one of the highest mortality ratios amongst other malignancies and this can much be attributed to the late diagnosis of the disease. Saliva has long been tested as a valuable tool for drug monitoring and the diagnosis systemic diseases among which oral cancer. The new emerging technologies in molecular biology have enabled the discovery of new molecular markers (DNA, RNA and protein markers) for oral cancer diagnosis and surveillance which are discussed in the current review.

Oral cytology revisited

During the last decade, oral cytology has once again become the focus of scientific research. This new interest is due to the introduction of a cytobrush for cell collection as well as a computer-assisted analysis (Oral CDx). Although promising, the sensitivity and specificity of conventional oral brush cytology remains limited. To circumvent the problems and improve the accuracy, various adjunctive analytical methods have been attempted. DNA analysis, immunocytochemical and molecular analysis are suggested methodological cytology approaches to improve the validity of oral brush cytology. An increase in sensitivity (up to 100%) and specificity (up to 100%) of oral brush biopsy has been reported on localized pre-malignant and malignant lesions. Oral brush biopsy probably will not replace histopathology in the definitive diagnosis of oral cancer, but it might be valuable for the prevention of misdiagnosis of clinically doubtful oral lesions and for the monitoring of lesions that might proceed on to oral cancer.

Oral cancer: a prosthodontic diagnosis

The prosthodontic literature is replete with articles addressing the reconstruction, psychological adaptation, prosthesis success, quality of life, need for careful follow-up, and many other issues related to the patient who has undergone surgery, radiation, and/or chemotherapy for oral malignant neoplasms. However, in the prosthodontic professional literature, there is a paucity of information related to the early diagnosis and referral of lesions that may represent premalignant or malignant neoplasia. This article will describe the rationale, epidemiology, and appearance of oral premalignant and malignant mucosal lesions as well as the state-of-the-art diagnostic tools currently available to prosthodontists to ensure that their patients are diagnosed at the earliest possible time.

Human calmodulin-like protein (CLP) expression in oral squamous mucosa and in malignant transformation

PURPOSE

The purpose of this study was to test whether calmodulin-like protein (CLP) is expressed in normal human oral mucosal cells and if downregulation of CLP occurs in malignant transformation.

MATERIALS AND METHODS

Oral mucosal tissue was taken from three individuals in a double-blind manner. The samples were cut, measured, and homogenized. Total RNA was extracted and reverse transcribed. Each cDNA sample was subjected to polymerase chain reaction (PCR). PCR fragments were purified, cloned, and sequenced to verify the presence of CLP. Three oral mucosal tissue samples with biopsy-confirmed squamous cell carcinoma were obtained. These samples demonstrated regions of normal epithelial cells as well as invasive squamous cell carcinoma. One normal breast epithelial sample was also obtained for positive control. Sections were stained with an affinity-purified CLP antibody and counterstained with a diluted hematoxylin. Two observers evaluated the specimens for expression of CLP. Staining patterns and intensity were noted in normal oral mucosa, comparing them to the normal breast epithelium sample. Staining patterns and intensity were then observed in squamous tumor cells, comparing them to the patterns of benign squamous mucosa.

RESULTS

CLP coding sequences were positively identified from the normal oral mucosal tissue samples by reverse transcription and polymerase chain reaction (RT-PCR) with 100% identity to the published CLP sequence (accession #M58026). In the three oral mucosa tissue samples with known squamous cell carcinoma, expression of CLP was readily detected in areas of normal oral mucosa, while a notable downregulation of CLP expression occurred in areas of malignant transformation. The staining intensity was equivalent to the staining seen in the benign breast epithelium used as a control. In the areas of squamous cell carcinoma, a decrease in CLP immunoreactivity occurred. There was a sharp contrast in staining quality and clarity between benign and malignant tissue. In the majority of the carcinoma regions, a complete lack of immunoreactivity was noted.

CONCLUSIONS

The RNA for human CLP is found in normal oral mucosa. CLP expression is seen in normal oral mucosa with a downregulation of CLP expression in malignant transformation.

[Surgical treatment options for squamous cell carcinoma of the oral cavity]

The squamous cell carcinoma of the oral cavity comprises 3% of all new cancer cases. 10% have a hereditary component. Smokers stand at a 3-fold higher risk with alcohol as an additive factor. 6 to 10 independent genetic events are expected to take place until invasive carcinoma occurs. Chromosomal deletion may also be detected in premalignant lesions. Staging is performed with inspection including endoscopy, CT- and MR-Scans and biopsy for the primary tumour and chest-X-ray, CT, Ultrasound and Scintigraphy for the N and M stage routinely. Therapeutic options that are proven best are radiation or/and surgery for T1 and T2 stages with a 5-year survival rate between 80% and 100%. Multimodal therapies, also including chemotherapy for higher stages result in 5-year survival rates between 55% and 62%. Since recurrence and metastasis have very poor prognosis sufficient and radical primary therapy is crucial. Palliative chemotherapy may be applied for functional improvement and pain release without statistical prove for increased survival rates.

Critical evaluation of diagnostic aids for the detection of oral cancer

Historically, the screening of patients for signs of oral cancer and precancerous lesions has relied upon the conventional oral examination. A variety of commercial diagnostic aids and adjunctive techniques are available to potentially assist in the screening of healthy patients for evidence of otherwise occult cancerous change or to assess the biologic potential of clinically abnormal mucosal lesions. This manuscript systematically and critically examines the literature associated with current oral cancer screening and case-finding aids or adjuncts such as toluidine blue, brush cytology, tissue reflectance and autofluorescence. The characteristics of an ideal screening test are outlined and the authors pose several questions for clinicians and scientists to consider in the evaluation of current and future studies of oral cancer detection and diagnosis. Although the increased public awareness of oral cancer made possible by the marketing of recently-introduced screening adjuncts is commendable, the tantalizing implication that such technologies may improve detection of oral cancers and precancers beyond conventional oral examination alone has yet to be rigorously confirmed.

Cell-based sensor for analysis of EGFR biomarker expression in oral cancer

Oral cancer is the sixth most common cancer worldwide and has been marked by high morbidity and poor survival rates that have changed little over the past few decades. Beyond prevention, early detection is the most crucial determinant for successful treatment and survival of cancer. Yet current methodologies for cancer diagnosis based upon pathological examination alone are insufficient for detecting early tumor progression and molecular transformation. To address this clinical need, we have developed a cell-based sensor to detect oral cancer biomarkers, such as the epidermal growth factor receptor (EGFR) whose over-expression is associated with early oral tumorigenesis and aggressive cancer phenotypes. The lab-on-a-chip (LOC) sensor utilizes an embedded track-etched membrane, which functions as a micro-sieve, to capture and enrich cells from complex biological fluids or biopsy suspensions. Once captured, "on-membrane" immunofluorescent assays reveal the presence and isotype of interrogated cells via automated microscopy and fluorescent image analysis. Using the LOC sensor system, with integrated capture and staining technique, EGFR assays were completed in less than 10 minutes with staining intensity, homogeneity, and cellular localization patterns comparable to conventional labeling methods. Further examination of EGFR expression in three oral cancer cell lines revealed a significant increase (p < 0.05) above control cells with EGFR expression similar to normal squamous epithelium. Results obtained in the microfluidic sensor system correlated well with flow cytometry (r(2) = 0.98), the "gold standard" in quantitative protein expression analysis. In addition, the LOC sensor detected significant differences between two of the oral cancer cell lines (p < 0.01), accounting for disparity of approximately 34 000 EGFR per cell according to quantitative flow cytometry. Taken together, these results support the LOC sensor system as a suitable platform for rapid detection of oral cancer biomarkers and characterization of EGFR over-expression in oral malignancies. Application of this technique may be clinically useful in cancer diagnostics for early detection, prognostic evaluation, and therapeutic selection. Having demonstrated the functionality of this integrated microfluidic sensor system, further studies using clinical samples from oral cancer patients are now warranted.

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.

Oral cancer: leukoplakia and squamous cell carcinoma

This article reviews the epidemiology, etiologic risk factors, clinical presentation, recognition, and diagnosis of oral precancer and cancer. The actual treatment and complications from treatment of oral cancer are discussed only briefly.

The sensitivity and specificity of the OralCDx technique: evaluation of 103 cases

In this study, we compared 103 OralCDx results with the histological findings of 96 clinical sites in 80 patients (33 females; 64.3+/-13.7 years and 47 males; 53.2+/-11.5 years). The histological findings were classified as follows: compatible with oral leukoplakia (OL; n = 60) or oral lichen planus (OLP; n = 17), both without dysplasia; dysplasia in OL or OLP (n = 9); and oral squamous cell carcinoma (OSCC; n = 17). There were seven (6.8%) specimens with an inadequate cell count. Overall, the sensitivity of the OralCDx technique to detect dysplasia and OSCC was 92.3% (95% CI: 74.9-99.1%), and the specificity was 94.3% (95% CI: 86.0-98.4%). The positive likelihood ratio (LR+) was 16.2 (95% CI: 6.2-42.1) and the negative likelihood ratio (LR-) was 0.08 (95% CI: 0.02-0.31). In conclusion, these figures are in agreement with previously published data and support the use of OralCDx as a screening tool of oral lesions, but further trials are still necessary.

A non-invasive technique for studying oral epithelial Epstein-Barr virus infection and disease

Oral Epstein-Barr virus (EBV) infection is associated with hairy leukoplakia and possibly other oral diseases. Many studies of oral EBV infection utilize surgical specimens. This study tested a non-invasive brush biopsy technique as an alternative to surgical biopsy to study oral EBV infection and disease. Paired, same-site, samples of tongue epithelium were obtained from research subjects, first by brush and then by surgical biopsy. Brush cells and surgical specimens were fixed and prepared for histologic sectioning and/or processed for nucleic acid extraction. Brush cell pellet sections proved equivalent to surgical specimen tissue sections for hairy leukoplakia diagnosis by routine histologic staining and EBV immunohistochemistry or in situ hybridization. Amplification of EBV sequences demonstrated superiority of the brush cells over surgical specimens for both sensitivity (90% vs. 73%) and negative predictive value (93% vs. 82%). This non-invasive brush biopsy technique should facilitate larger, prospective studies of oral EBV infection and pathogenesis.

Oral malignancies associated with negative transepithelial brush biopsy

PURPOSE

This study was performed to assess the incidence of negative brush biopsy for oral lesions later demonstrated histologically to be squamous cell carcinoma.

METHODS

All diagnoses of oral squamous cell carcinoma from a university oral pathology service for the period June 2000 through March 2002 were reviewed to determine if any had previously undergone brush biopsy reported to be "negative for epithelial abnormality." Those cases identified were further investigated to determine the time lapse between brush biopsy and definitive tissue diagnosis.

RESULTS

Four cases of brush biopsy negative squamous cell carcinoma were identified from 115 total cases of malignancy (3.5%). The average time from brush biopsy to tissue diagnosis was 117.25 days (range, 5 to 292 days).

CONCLUSION

False negative reports are possible with the oral brush biopsy technique. Persistent lesions should undergo tissue biopsy for definitive diagnosis.

Screening programmes for the early detection and prevention of oral cancer

BACKGROUND

Although the second half of the last century has generated a rich and complex body of knowledge, the burden of oral cancer is still largely present. As with other cancers, there has been a strong debate whether screening strategies for oral cancer such as visual examination, the use of toluidine blue or newer methods such as brush biopsy or fluorescence imaging are effective in reducing the mortality rate associated with oral cancer.

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 September 2002, The Cochrane Library - Issue 2, 2002), 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 potentially premalignant oral lesions using visual examination, toluidine blue, fluorescence imaging or brush biopsy.

DATA COLLECTION AND ANALYSIS

The search found 100 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 have been undertaken by two independent reviewers.

MAIN RESULTS

One ongoing randomised controlled trial has been included (n = 13 clusters: 153,708 eligible subjects, 130,799 included subjects). There was no difference in the age-standardised oral cancer mortality rates for the screened group (21.2/1000,000 person years) and the control group (21.3/100,000 person years). However this study has some methodological weaknesses.

REVIEWER'S CONCLUSIONS

Given the limitation of evidence (only one included randomised controlled trial) and the potential methodological weakness in the included study, it is valid to say that there is no 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 other methods of screening, toluidine blue, fluorescence imaging or brush biopsy, are either beneficial or harmful. Further cost-effective, high quality studies to assess the efficacy and effectiveness of screening are required. 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.

Marrow failure

This chapter describes the clinical presentation and molecular basis of two inherited bone marrow failure syndromes, Fanconi anemia (FA), and Diamond-Blackfan anemia (DBA). It also provides an update on diagnostic and therapeutic approaches to bone marrow failure of all types (inherited and acquired) in pediatric patients. In Section I, Dr. Alan D'Andrea reviews the wide range of clinical manifestations of Fanconi anemia. Significant advances have been made in understanding the molecular pathogenesis of FA. On the basis of these advances, new diagnostic assays and treatment options are now available. In Section II, Dr. Niklas Dahl examines the clinical features and molecular pathogenesis of Diamond-Blackfan anemia. The possible links between the RPS19 gene (DBA gene) and the erythropoiesis defect are considered. In Section III, Drs. Eva Guinan and Akiko Shimamura provide an algorithm for the diagnostic evaluation and treatment of children with inherited or acquired aplastic anemia. Through the presentation of a case study of a pediatric patient with bone marrow failure, he provides an overview of the newest tests and treatment options.