Is there a natural limit of the transformation rate of oral leukoplakia?

Practice patterns for initial management of oral leukoplakia amongst otolaryngologists and oral and maxillofacial surgeons

OBJECTIVE

Oral leukoplakia is encountered frequently by otolaryngologists and oral and maxillofacial surgeons (OMFS). There are no consensus practice management guidelines for oral leukoplakia, resulting in heterogeneity in practice patterns. Characterization of practice patterns of providers who treat oral leukoplakia will be valuable to establish standards of care and future practice guidelines.

MATERIAL AND METHODS

A survey was designed by the American Head and Neck Society Cancer Prevention Service collecting demographic and practice management data for treating oral leukoplakia. The survey was approved and distributed to members of the American Academy of Otolaryngology-Head and Neck Surgery and American Association of Oral and Maxillofacial Surgeons. Data analysis was performed using chi square and t-test where appropriate.

RESULTS

396 responses were collected: 83 OMFS, 81 head and neck fellowship-trained providers, and 232 otolaryngologists (non-head and neck fellowship-trained). Providers saw a wide volume of oral leukoplakia (23.0% >30 cases/year, 35.1% 11-30 cases/year, 41.2% 10 or less cases/year), with OMFS seeing more cases of oral leukoplakia. Factors most associated with consideration of initial biopsy included physical exam findings (94.4%), erythroplakia (82.3%), and smoking status (81.6%). The majority of respondents saw patients in follow-up within 1 month (24.8%) or within 1-3 months (46.5%).

CONCLUSION

This survey identifies a range of practice patterns in initial management of oral leukoplakia, including indications for biopsy, and time for follow-up. This data provide insight into practice patterns amongst different groups of providers and can potentially lead to consensus guidelines for initial management of oral leukoplakia.

Clinical predictors of malignant transformation and recurrence in oral potentially malignant disorders: A systematic review and meta-analysis

OBJECTIVE

We performed a systematic review dedicated to pooling evidence for the associations of clinical features with malignant transformation (MT) and recurrence of 3 oral potentially malignant disorders (OPMDs) (actinic cheilitis [AC], oral leukoplakia [OL], and proliferative verrucous leukoplakia [PVL]).

STUDY DESIGN

We selected studies that included clinical features and risk factors (age, sex, site, size, appearance, alcohol intake, tobacco use, and sun exposure) of OL, PVL, and AC associated with recurrence and/or MT.

RESULTS

Based on the meta-analysis results, non-homogeneous OL appears to have a 4.53 times higher chance of recurrence after treatment. We also found 6.52 higher chances of MT of non-homogeneous OL. Another clinical feature related to higher MT chances is the location (floor of the mouth and tongue has 4.48 higher chances) and the size (OL with >200 mm2 in size has 4.10 higher chances of MT). Regarding habits, nonsmoking patients with OL have a 3.20 higher chance of MT. The only clinical feature related to higher chances of MT in patients with PVL was sex (females have a 2.50 higher chance of MT).

CONCLUSIONS

Our study showed that some clinical features may indicate greater chances of recurrence after treatment and MT of OPMD.

A case of tongue cancer manifesting from oral leukoplakia after long-term administration of pegylated liposomal doxorubicin

We present a case of tongue cancer manifestation from oral leukoplakia after administration of pegylated liposomal doxorubicin (PLD). A 56-year-old woman was diagnosed with ovarian cancer. After preoperative chemotherapy with paclitaxel and carboplatin (TC), she underwent interval debulking surgery. Five cycles of TC therapy were carried out as adjuvant chemotherapy; however, recurrence was observed. Despite administration of gemcitabine-carboplatin therapy, the patient's condition was judged as advancing to a progressive disease. PLD treatment was completed at a total dose of 1140 mg/m². Two months after the end of treatment, the patient was diagnosed with leukoplakia. The leukoplakia lesion became thicker at each 3-month follow-up. She was diagnosed with tongue cancer and underwent a partial resection 2 years and 3 months after the completion of PLD treatment. Our report suggests that the risk of malignant transformation to tongue cancer persists even after the completion of treatment with PLD.

Cytomorphometric analysis of squames obtained from normal mucosa, leukoplakia and oral squamous cell carcinoma

Introduction

Exfoliative cytology is becoming increasingly important in the early diagnosis of oral cancers, as a procedure for obtaining cell samples, which can be analyzed by sophisticated diagnostic techniques. Quantitative techniques, based on the evaluation of parameters such as nucleus area, cytoplasm area and nucleus-to-cytoplasm area ratio, may increase the sensitivity of exfoliative cytology for early diagnosis of oral cancers, since these techniques are precise, objective and reproducible.

Objectives

This study was undertaken to employ the cytomorphometric quantitative techniques to determine the value of exfoliative cytology and to assess this method to analyze the effectiveness in providing additional diagnostic test for the detection of early oral malignancy.

Materials and Methods

The study consisted of three groups. The experimental group comprised of 20 subjects with oral leukoplakia and 20 subjects with oral squamous cell carcinoma of the buccal mucosa. The control group comprised of 10 apparently healthy subjects. They were subjected to clinical examination and cytosmear of the buccal mucosa. A standard wooden tongue spatula/metal spatula moistened with normal saline was used to obtain scrapings of buccal mucosa. The scrapings were spread on plain glass slides and immediately fixed in Biofix spray, followed by staining with the Papanicolaou technique. Then, the microscopic pictures were captured onto a computer and are cytomorphometrically analyzed using an image analyzer. Since this study involved multiple groups, one-way analysis of variance (ANOVA) was used for comparing the parameters for multiple groups. Where significant difference was seen, the ANOVA test was followed by Mann-Whitney test, for pairwise comparison.

Results

The mean count of nuclear area and nuclear diameter showed an increase from Group I to Group II, Group I to Group III and Group II to Group III, which was statistically significant. The mean count of cell area and cell diameter showed a decrease from Group I to Group II, Group I to Group III and Group II to Group III, which was statistically significant. The mean count of nuclear/cytoplasm area ratio showed an increase from Group I to Group II, Group I to Group III and Group II to Group III, which was statistically significant.

Conclusion

With the advancements in the field of quantitative exfoliative cytology, interest in oral cytology has once again emerged in the diagnosis of oral premalignancy and malignancy. Computer-aided analysis with the sophisticated software increases the speed and accuracy of cytological measurements, which are repeatable. These versatile systems facilitate quantitative oral cytological assessments, which may become a viable procedure for the early detection of oral premalignancy and malignancy.

Recurrence in Oral Premalignancy: Clinicopathologic and Immunohistochemical Analysis

Oral leukoplakia (OL) has a propensity for recurrence and malignant transformation (MT). Herein, we evaluate sociodemographic, clinical, microscopic and immunohistochemical parameters as predictive factors for OL recurrence, also comparing primary lesions (PLs) with recurrences. Thirty-three patients with OL, completely removed either by excisional biopsy or by laser ablation following incisional biopsy, were studied. Selected molecules associated with the STAT3 oncogenic pathway, including pSTAT3, Bcl-xL, survivin, cyclin D1 and Ki-67, were further analyzed. A total of 135 OL lesions, including 97 PLs and 38 recurrences, were included. Out of 97 PLs, 31 recurred at least once and none of them underwent MT, during a mean follow-up time of 48.3 months. There was no statistically significant difference among the various parameters in recurrent vs. non-recurrent PLs, although recurrence was most frequent in non-homogeneous lesions (p = 0.087) and dysplastic lesions recurred at a higher percentage compared to hyperplastic lesions (34.5% vs. 15.4%). Lower levels of Bcl-xL and survivin were identified as significant risk factors for OL recurrence. Recurrences, although smaller and more frequently homogeneous and non-dysplastic compared to their corresponding PLs, exhibited increased immunohistochemical expression of oncogenic molecules, especially pSTAT3 and Bcl-xL. Our results suggest that parameters associated with recurrence may differ from those that affect the risk of progression to malignancy and support OL management protocols favoring excision and close monitoring of all lesions.

Clinicopathologic factors associated with malignant transformation of oral leukoplakias: a retrospective cohort study

It is clinically challenging to identify oral leukoplakias that have a high risk of undergoing malignant transformation. The aim of this retrospective study was to elucidate the associations between malignant transformation of oral leukoplakias and various clinicopathologic factors. Patients with a diagnosis of clinical oral leukoplakia, verified through histopathologic examination and with access to digital images of the lesion, were retrospectively included for the period 2003-2013. Using the clinical images, all lesions were re-evaluated regarding diagnosis and clinical subtype. Of the 234 included patients, with a median follow-up of 9 years, 27 (11.5%) developed oral squamous cell carcinoma. Among the clinicopathologic factors investigated, non-homogeneous oral leukoplakia (OL), OL with dysplasia, and OL localized to the tongue showed statistically significant increased rates of malignant transformation in the multivariate Cox regression analysis. Non-homogeneous OL showed a 15.2-times higher transformation rate than homogenous OL (P<0.001). Dysplastic leukoplakias developed into carcinomas 2.4-times more often than did non-dysplastic leukoplakias (P=0.048). OL located on the tongue showed a 2.8-times higher malignant transformation rate than OLs at other oral locations (P=0.018), when other locations were combined into one group. Non-homogeneous OL, OL with dysplasia, and OL localized to the tongue have higher transformation rates.

Tissue biomarkers for predicting the risk of oral cancer in patients diagnosed with oral leukoplakia: A systematic review

OBJECTIVES

We performed a systematic review to evaluate the published biomarkers related to oral leukoplakia (OL), aiming to identify the biomarkers that indicate any future risk of cancer in patients with oral leukoplakia.

METHODS

A search strategy was developed for three main electronic databases: PubMed, Cochrane Library, and EBSCO, and also for Google Scholar, until February 28, 2020. The study selection was performed in a two-phase process aiming at studies assessing tissue biomarkers for "malignant transformation of OL." Risk of bias analysis of included studies was performed using the Quality in Prognosis Studies Tool.

RESULTS

From 3,130 articles initially identified by searching databases, a total of 46 studies were included in this systematic review, with a combined sample of 3,783 patients, of whom 1,047 presented with malignant transformation of a previously diagnosed OL as reported by the authors. The cancer incidence in the whole group was 27.6% (range: 5.4% to 54.1%). The studies were derived from different geographic areas, including Asia (n = 21), Europe (n = 15), North America (n = 9), and Oceania (n = 1). There were 49 different molecular biomarkers evaluated in the 46 included studies: p53 and podoplanin proteins were the most frequently reported, followed by abnormalities at particular chromosomal loci (e.g., LOH). Risk of bias analysis revealed concerns associated with "measurement of prognostic factor," "study confounding" and "statistical analysis and reporting."

CONCLUSIONS

Substantial heterogeneity and lack of standardized reporting of data among the studies were identified. The most promising biomarkers reported to have a significant association with the malignant transformation in OL included podoplanin and chromosomal loci abnormalities. A critical examination of the follow-up studies on OL published so far indicated that tissue biomarkers that could predict the risk of oral cancer in patients with OL are still in a discovery phase.

MicroRNAs in oral cancer: Biomarkers with clinical potential

Oral cancer is the sixteenth most common cancer globally, with a relatively poor five-year survival rate of 50%. Thus it is imperative to understand the biology of oral cancer and examine alternative prognostic and therapeutic targets for oral cancer. MicroRNAs (miRNAs) are small non-coding RNAs mediating gene expression at the post-transcriptional level through mRNA degradation or translational repression. miRNAs play an essential role in cancer development and oncogenic cell processes. miRNA deregulation is observed in oral cancer and associated with prognosis. However, the role of miRNAs and their clinical implications in oral cancer is not clear. The current review highlights the miRNA profile of oral cancer and discusses the diagnostic, prognostic and potential therapeutic targets with clinical implications. miRNAs mediate activation or suppression of signalling pathways associated with oral cancer. Hence, a panel of select deregulated miRNAs may indicate clinicopathological features, personalised treatment outcome and provide novel lead profiles of oral cancer. The translational applications of miRNAs may lead to better management and survival of oral cancer patients. The compiled data provides a platform for consideration of miRNA signatures as potential biomarkers for early oral cancer diagnosis, prognosis and as novel molecular therapies.

Laser excision of oral leukoplakia: Does it affect recurrence and malignant transformation? A systematic review and meta-analysis

Oral leukoplakia (OL) is a white lesion with high potential of recurrence and malignant transformation. The variable clinical and histopathological features of OL may potentially impact both treatment and prognosis. Current literature shows that post treatment rates of recurrence and malignant transformation vary widely. The use of surgical lasers have been proposed with the objective of improving outcomes. We performed a systematic review and a comprehensive meta-analysis dedicated to pooling the rates of recurrence and malignant transformation of OL lesions treated using the main types of surgical lasers available. Scopus, MEDLINE/PubMed, and Embase were searched electronically. A total of 36 articles met the inclusion criteria. Selected studies included OL lesions that were treated by evaporation or excision using Nd:YAG laser, Er:YAG laser, CO2 laser, KTP laser, or diode laser. The results of this systematic review and meta-analysis suggest that surgical laser excision of OL may decrease recurrence rates but have no effect on the malignant transformation of OL when compared with conventional treatments.

Investigation of viral etiology in potentially malignant disorders and oral squamous cell carcinomas in non-smoking, non-drinking patients

Head and neck squamous cell carcinomas (HNSCC) are the seventh most frequent cancers. Among HNSCCs, oral squamous cell carcinomas (OSCCs) include several anatomical locations of the oral cavity, but exclude the oropharynx. The known risk factors for OSCCs are mainly alcohol consumption and tobacco use for at least 75-80% of cases. In addition to these risk factors, Human papillomavirus (HPV) types 16 and 18, classified as high-risk (HR) HPV genotypes, are considered as risk factors for oropharyngeal cancers, but their role in the development of OSCC remains unclear. We tested the hypothesis of viral etiology in a series of 68 well-characterized OSCCs and 14 potentially malignant disorders (PMD) in non-smoking, non-drinking (NSND) patients using broad-range, sensitive molecular methodologies. Deep-sequencing of the transcriptome did not reveal any vertebrate virus sequences other than HPV transcripts, detected in only one case. In contrast, HPV DNA was detected in 41.2% (28/68) and 35.7% (5/14) of OSCC and PMD cases, respectively. Importantly, 90.9% (30/33) of these belonged to the Betapapillomavirus genus, but no viral transcripts were detected. Finally, high-throughput sequencing revealed reads corresponding to transcripts of the Trichomonas vaginalis virus (TVV), which were confirmed by RT-PCR in two OSCCs. Our results strongly suggest that Alphapapillomavirus genotypes classified as HR are not involved in the development of OSCCs in NSND patients and that known oncogenic infectious agents are absent in these specific OSCCs. Any possible direct or indirect role of Betapapillomavirus genus members and TVV in OSCCs remains speculative and requires further investigation.

Malignant transformation rate of oral leukoplakia-systematic review

OBJECTIVE

The aim of this study was to perform a systematic review of prevalence studies to determine the rate of malignant transformation of oral leukoplakia and assess the influence of demographic factors (age, gender, and geographic region) on the overall transformation rate.

STUDY DESIGN

A search was conducted for publications until July 2019 in 4 electronic databases and peer-reviewed journals. A manual search was performed on the bibliographies of the collected articles, and the authors were contacted for additional information. This study was previously registered with the trial number CRD42019126909 and study quality assessed through established methods. The results were expressed by means of proportions or odds ratios with a 95% confidence interval. Meta-regression was undertaken to evaluate possible sources of heterogeneity, and funnel plot visual analysis was performed to assess publication bias.

RESULTS

The 34 observational epidemiologic studies included reported data on 26,209 patients with oral leukoplakia from 18 different countries. Meta-analysis of 32 studies (23,489 patients) presented an estimated overall mean proportion of malignant transformation rate of 9.70% (7.80-11.70) (I² = 98.66%; τ² < 0.001; χ² = 23.18; degrees of freedom [df] = 31). When comparing genders, the odds ratio favored males with 0.622 (0.468-0.826) (I² = 29.77%; τ² = 0.089; χ² = 22.78; df = 16).

CONCLUSIONS

Within the limitations of the included studies in this systematic review, the results suggest that the malignant transformation rate was dependent on demographic factors and follow-up time. Future studies should include the development of guidelines to standardize the methodology for long-term follow-up assessment, thus reducing the risk of bias.

Diabetes mellitus and oral cancer/oral potentially malignant disorders: A systematic review and meta-analysis

The objective was to evaluate current evidence on the prevalence and risk of oral cancer and potentially malignant oral disorders among patients with diabetes mellitus. We searched PubMed, Embase, Web of Science, and Scopus for observational studies published before November 2019. We evaluated the study quality using GRADE, QUIPS, and a specific method for systematic reviews addressing prevalence questions. Meta-analyses were conducted, and heterogeneity and publication bias were examined. A total of 1,489 studies were found, 116 analyzed in full text, 52 included in qualitative synthesis and 49 meta-analyzed. Pooled prevalence (PP) of oral cancer in patients with diabetic was 0.25% (95% CI = 0.15-0.39)-250 per 100,000 patients with diabetes mellitus -with a greater chance of oral cancer among patients with diabetes mellitus (OR = 1.41 [95% CI = 1.10-1.81], p = .007). Patients with oral cancer and diabetes mellitus had a higher mortality than controls (HR = 2.09 [95%CI = 1.36-3.22], p = .001). Leukoplakia had a PP = 2.49% (95% CI = 1.14-4.29)-2,490 per 100,000 patients with diabetes mellitus -(OR = 4.34 [95% CI = 1.14-16.55], p = .03). A PP of 2.72 (95% CI = 1.64-4.02) was obtained for oral lichen planus among patients with diabetic -2,720 per 100,000 patients with diabetes mellitus (OR = 1.87 [95% CI = 1.37-2.57], p < .001). A low PP was estimated for erythroplakia (0.02%[95%CI = 0.00-0.12]-20 per 100,000 patients with diabetes mellitus. In conclusion, patients with diabetes mellitus have a higher prevalence and greater chance of oral cancer and OPMD development in comparison with non-diabetic patients. In addition, patients with oral cancer suffering from diabetes mellitus have a higher mortality compared to non-diabetic patients with oral cancer.

Saliva and Oral Diseases

Saliva is a fascinating biological fluid which has all the features of a perfect diagnostic tool. In fact, its collection is rapid, simple, and noninvasive. Thanks to several transport mechanisms and its intimate contact with crevicular fluid, saliva contains hundreds of proteins deriving from plasma. Advances in analytical techniques have opened a new era-called "salivaomics"-that investigates the salivary proteome, transcriptome, microRNAs, metabolome, and microbiome. In recent years, researchers have tried to find salivary biomarkers for oral and systemic diseases with various protocols and technologies. The review aspires to provide an overall perspective of salivary biomarkers concerning oral diseases such as lichen planus, oral cancer, blistering diseases, and psoriasis. Saliva has proved to be a promising substrate for the early detection of oral diseases and the evaluation of therapeutic response. However, the wide variation in sampling, processing, and measuring of salivary elements still represents a limit for the application in clinical practice.

Noninvasive assessment of oral lesions using elastic light single-scattering spectroscopy: a pilot study

PURPOSE

In the present study, we investigated the potential application of elastic light single-scattering spectroscopy (ELSSS) as a noninvasive, adjunctive tool to differentiate between malignant and benign oral lesions in vivo.

METHODS

ELSSS spectra were acquired from 52 oral lesions of 47 patients prior to surgical biopsy using a single optical fiber probe. The sign of the spectral slope was used as a diagnostic parameter and was compared to the histopathology findings to obtain sensitivity and specificity of the ELSSS system in differentiating between benign and malignant tissues.

RESULTS

The sign of the spectral slope was positive for the benign tissues and negative for the malignant tissues. Nine malignant lesions and one high-grade dysplasia were correctly classified as cancerous. Six out of the ten low-grade dysplasia were correctly classified as cancerous, and four of them were misclassified as benign. Thirty benign lesions were correctly classified as benign, and two were misclassified as malignant. Our results indicate that the sign of the spectral slope enables the differentiation between malignant and benign oral lesions with a sensitivity of 80% and specificity of 94%.

CONCLUSIONS

ELSSS has the potential to be developed as an adjunctive screening tool in the noninvasive evaluation of oral lesions in vivo. This new diagnostic system may reduce the number of unnecessary biopsies.

Recurrence rates after surgical removal of oral leukoplakia-A prospective longitudinal multi-centre study

Oral leukoplakia (OL) is a potentially malignant oral disorder. The Gold Standard treatment is to remove surgically the OL. Despite optimal surgery, the recurrence rates are estimated to be 30%. The reason for this is unknown. The aim of this study was to investigate the clinical factors that correlate with recurrence after surgical removal of OL. In a prospective study data were collected from 226 patients with OL. Forty-six patients were excluded due to incomplete records or concomitant presence of other oral mucosal diseases. Overall, 180 patients proceeded to analysis (94 women and 86 men; mean age, 62 years; age range, 28–92 years). Clinical data, such as gender, diagnosis (homogeneous/non-homogeneous leukoplakia), location, size, tobacco and alcohol use, verified histopathological diagnosis, and clinical photograph, were obtained. In patients who were eligible for surgery, the OL was surgically removed with a margin. To establish recurrence, a healthy mucosa between the surgery and recurrence had to be confirmed in the records or clinical photographs. Statistical analysis was performed with the level of significance set at P<0.05. Of the 180 patients diagnosed with OL, 57% (N = 103) underwent surgical removal in toto. Recurrence was observed in 43 OL. The cumulative incidence of recurrence of OL was 45% after 4 years and 49% after 5 years. Fifty-six percent (N = 23) of the non-homogeneous type recurred. Among snuff-users 73% (N = 8) cases of OL recurred. A non-homogeneous type of OL and the use of snuff were significantly associated with recurrence after surgical excision (P = 0.021 and P = 0.003, respectively). Recurrence was also significantly associated with cancer transformation (P<0.001). No significant differences were found between recurrence and any of the following: dysplasia, site of lesion, size, multiple vs. solitary OL, gender, age, use of alcohol or smoking. In conclusion, clinical factors that predict recurrence of OL are non-homogeneous type and use of snuff.

Expression of cluster differentiation-44 stem cell marker in grades of oral epithelial dysplasia: A preliminary study

Introduction:

Oral cancer is one among the alarming diseases related to oral cavity. Its prevalence and incidence have increased in many folds, in the past decade. This has led the investigators to find the preliminary stages and related early evaluating methods to restrain it. Few clinical lesions such as leukoplakia, erythroplakia, oral submucous fibrosis and lichen planus reflected malignant changes. These premalignant disorders provided scope to assess the underlying cellular and molecular events, which shall be helpful in early detection, aggressiveness and prognosis of the patient.

Materials and Methods:

Forty formalin fixed, paraffin embedded blocks were utilized and evenly subdivided into Group I – control tissue, Group II – mild epithelial dysplasia, Group III – moderate epithelial dysplasia and Group IV – severe epithelial dysplasia. The study group was categorized based on the WHO classification of dysplasia 2005. Routine staining was performed to reconfirm the diagnosis of all the samples. Simultaneously, immunohistochemical staining was done with cluster differentiation-44 (CD44) antibody. Positive cells were counted on 10 representative fields with a minimum of 100 cells per field using ×20.

Statistical Analysis:

Comparison of four groups with respective to number of positive cells was done using Kruskal–Wallis ANOVA test. Pair-wise comparison of three grades of oral epithelial dysplasia and the controls was done using Mann–Whitney U test.

Results:

The mean of Group I is 745.50, Group II is 665.20, Group III is 530.10 and Group IV is 322.90. A statistically significant P = 0.00001 was ascertained on comparison of the mean between the groups.

Conclusion:

CD44, a cell membrane marker could help in cell adhesion and cell-cell interactions. Loss of CD44 expression enhances the binding of the growth factors with their principle receptors that enhances the cellular proliferation. It can be used as a prognostic marker for identifying the rate of malignant transformation in these disorders.

Salivary biomarkers for oral cancer and pre-cancer screening: a review

OBJECTIVE

The objective of the study was to conduct a systematic review of the literature assessing potential salivary biomarkers of oral cancer and pre-cancer and discuss emerging issues and challenges in relation to oral cancer and pre-cancer diagnostics.

MATERIALS AND METHODS

Search for articles involved the Medline, PubMed, and EMBASE. Specific terms were used from January 1995 to March 2017 by three experts.

RESULTS

This search collected 270 articles, of which 105 articles such as reviews, case reports, news, letter to editor, etc. in first round and 117 articles such as publications in other languages than English, non-human studies, etc. were excluded. The remaining 48 articles considered analyzing whole saliva as well as specific gland saliva. Thirty-one studies considered oral stimuli such as eating, drinking, and oral hygiene practices for varied periods of time prior to sample collection. The time of collection of saliva was morning in most studies, but the exact time of collection was not mentioned. Three studies showed to have evaluated the whole saliva without centrifugation. Two-dimensional gel electrophoresis and tandem mass spectrometry were the most commonly used methods. Most of the potential salivary biomarkers of oral cancer are salivary proteins.

CONCLUSION

Combination approach of salivary biomarkers could be used as screening tool to improve early detection and diagnostic precision of oral pre-cancer and cancer.

CLINICAL RELEVANCE

The current findings are of importance for clinicians and researchers to mitigate the challenges in salivary-based diagnosis of oral cancer and to evaluate reliable, specific, and sensitive salivary biomarkers for oral pre-cancer and cancer diagnosis.

Oral leukoplakia and proliferative verrucous leukoplakia: a review for dental practitioners

Objectives To provide an overview of the current thinking in terms of the diagnosis and management of oral leukoplakia and proliferative verrucous leukoplakia as relevant to general dental practitioners.Data sources, data selection, data extraction, data synthesis We searched the MEDLINE Ovid, EMBASE databases and the Cochrane Library, (1990 to 16 April 2017), restricting our search to English language with the following key words: leukoplakia, white patch, proliferative verrucous leukoplakia, precancerous lesion, premalignant lesions, potentially malignant oral conditions and potentially malignant oral disorders. The two authors selected key papers and engaged in collaborative data extraction and synthesis of the selected reference material.Conclusions General dental practitioners (GDPs) are likely to encounter patients with a known or yet undiagnosed oral leukoplakia in their clinical practice. The diagnosis is clinically based as there are no pathognomonic histopathological features. The definition of leukoplakia has evolved over the years. The importance of recognition and appropriate management relating to this condition is described particularly as it is one of the oral potentially malignant lesions. The inferred increased risk of malignant transformation is well documented however controversy still persists in terms of the appropriate management for these lesions. Proliferative verrucous leukoplakia is a recalcitrant, often widespread and multifocal distinct type of leukoplakia. It is considered to have a high rate of malignant transformation with implications in terms of lifelong monitoring both clinically and histopathologically. A high index of suspicion is important for general dental practitioners in order to identify such lesions that would require onward referral for further investigation and management.

CpG location and methylation level are crucial factors for the early detection of oral squamous cell carcinoma in brushing samples using bisulfite sequencing of a 13-gene panel

Background

Oral squamous cell carcinoma (OSCC) is usually diagnosed at an advanced stage and is commonly preceded by oral premalignant lesions. The mortality rates have remained unchanged (50% within 5 years after diagnosis), and it is related to tobacco smoking and alcohol intake. Novel molecular markers for early diagnosis are urgently needed. The purpose of this study was to evaluate the diagnostic value of methylation level in a set of 18 genes by bisulfite next-generation sequencing.

Methods

With minimally invasive oral brushing, 28 consecutive OSCC, one squamous cell carcinoma with sarcomatoid features, six high-grade squamous intraepithelial lesions (HGSIL), 30 normal contralateral mucosa from the same patients, and 65 healthy donors were evaluated for DNA methylation analyzing 18 target genes by quantitative bisulfite next-generation sequencing. We further evaluated an independent cohort (validation dataset) made of 20 normal donors, one oral fibroma, 14 oral lichen planus (OLP), three proliferative verrucous leukoplakia (PVL), and two OSCC.

Results

Comparing OSCC with normal healthy donors and contralateral mucosa in 355 CpGs, we identified the following epigenetically altered genes: ZAP70, ITGA4, KIF1A, PARP15, EPHX3, NTM, LRRTM1, FLI1, MIR193, LINC00599, PAX1, and MIR137HG showing hypermethylation and MIR296, TERT, and GP1BB showing hypomethylation. The behavior of ZAP70, GP1BB, H19, EPHX3, and MIR193 fluctuated among different interrogated CpGs. The gap between normal and OSCC samples remained mostly the same (Kruskal-Wallis P values < 0.05), but the absolute values changed conspicuously. ROC curve analysis identified the most informative CpGs, and we correctly stratified OSCC and HGSIL from normal donors using a multiclass linear discriminant analysis in a 13-gene panel (AUC 0.981). Only the OSCC with sarcomatoid features was negative. Three contralateral mucosa were positive, a sign of a possible field cancerization. Among imprinted genes, only MIR296 showed loss of imprinting. DNMT1, TERC, and H19 together with the global methylation of long interspersed element 1 were unchanged. In the validation dataset, values over the threshold were detected in 2/2 OSCC, in 3/3 PVL, and in 2/14 OLP.

Conclusions

Our data highlight the importance of CpG location and correct estimation of DNA methylation level for highly accurate early diagnosis of OSCC.

Electronic supplementary material

The online version of this article (doi:10.1186/s13148-017-0386-7) contains supplementary material, which is available to authorized users.

Evaluation of Different Laser-Supported Surgical Protocols for the Treatment of Oral Leukoplakia: A Long-Term Follow-Up

PURPOSE

The aim of this study was to evaluate the long-term success rate of oral leukoplakia treatments by using different laser-supported surgical protocols.

PATIENTS AND METHODS

Overall, 2347 diagnosed homogeneous oral leukoplakias were treated with CO₂ laser and were included in this study. Different surgical protocols (P) were used: P1 (SV = superficial scanning) was a complete superficial vaporization of the leukoplakia by a scanning mode in two passages respecting an overlapping. Only the visible white area was treated in one surgical session independently of the lesion size. P2 (CR1x1) was a complete excision of the lesions until a tissular depth of 1 mm and 1 mm of surrounding healthy-like tissue were attained. The visible white area was treated in one surgical session independently of the lesion size. P3 (CR1x3) was a complete excision of the lesions until a minimum tissue depth of 1 mm and 3 mm of surrounding healthy-like tissue were obtained. The visible white area was treated in one surgical session independently of the lesion size. P4 (PR1x3) was similar to the third one, but for patient comfort, the large lesions of leukoplakias (lesion size higher than 20 mm), the complete surgical excision of the leukoplakia was performed in multiple sessions that were spaced by 1 month (partial surgical removal of 10 mm per session). All patients were recalled at 2 and 8 weeks after surgery, and then every 2 months during the first year, every 4 months during the second year, and once a year for the follow-up period of 6 years. A biopsy was done once a year during the follow-up period in the surgical site when needed. The control consisted of checking the nature and the aspect of the healed mucosa to exclude an eventual recurrence of leukoplakia.

RESULTS

The percentage of permanent success after 6 years of follow-up was 5.7%, 69.7%, 97.8%, and 71.9%, respectively, for the first surgical protocol (SV), the second (CR 1 × 1), the third (CR 1 × 3), and the fourth (PR 1 × 3). The appearance of malignant transformation after laser treatment (during the follow-up period of 6 years) was 20%, 1%, and 0.2%, respectively, for the groups treated by the following protocols: 1 (SV), 2 (CR 1 × 1), and 4 (PR 1 × 3). Only in the third group CR1x3, no dysplasia or malignant transformation was noted. On the contrary, the appearance of malignant transformation in failed treated cases was 21.21% for the protocol 1 (SV), 3% for the protocol 2 (CR 1 × 1), and 0.6% for the protocol 4 (PR 1 × 3).

CONCLUSIONS

The results of this long-term follow-up of treated patients with oral homogeneous leukoplakias pointed out that the surgical laser protocol respecting the complete excision of leukoplakias, in one session, by the removal of a minimum of 1 mm in lesion depth and 3 mm of surrounding healthy-like tissues (CR 1 × 3) offers significantly the highest success rate.

Single nucleotide polymorphisms in an Indian cohort and association of CNTN4, MMP2 and SNTB1 variants with oral cancer

Oral cancer is a high incidence cancer in India primarily due to the prevalent tobacco/areca nut chewing habits and hence a major health concern. India constitutes 26% of the global oral cancer burden. Besides the well-established risk factors, the genomic constitution of an individual plays a role in oral cancer. The aim of the current study was to analyse genomic variants represented as single nucleotide polymorphisms (SNPs), analyse their prevalence and investigate risk association of allelotypes/genotypes to oral cancers. Eleven SNPs in genes associated with biological functions were analysed in an Indian cohort (n = 1000) comprising 500 oral cancer patients and 500 long term tobacco habitués as controls, using Allelic discrimination Real-Time PCR assay with SYBR Green dye. Fisher's exact test and Odds Ratio were used for statistical analysis. Increased risk was observed for rs9849237 CC [P = 0.008; OR 1.412 (1.09-1.82)] and rs243865 CT [P = 0.004; OR 1.469 (1.13-1.90)] genotypes, whereas rs9849237 CT [P = 0.034; OR 0.755 (0.58-0.97)], rs243865 CC [P = 0.002; OR 0.669 (0.51-0.86)] and rs10090787 CC [P = 0.049; OR 0.774 (0.60-0.99)] genotypes indicated decreased risk to oral cancer. The other SNPs showed equidistribution in both groups. Our data indicated genotypes and alleles in specific SNPs rs9849237, rs243865 and rs10090787 with increased/decreased risk to oral cancer.

Interventions for treating oral leukoplakia to prevent oral cancer

BACKGROUND

Oral leukoplakia is a relatively common oral lesion that, in a small proportion of people, precedes the development of oral cancer. Most leukoplakias are asymptomatic; therefore, the primary objective of treatment should be to prevent onset of cancer. This review updates our previous review, published in 2006.

OBJECTIVES

To assess the effectiveness, safety and acceptability of treatments for leukoplakia in preventing oral cancer.

SEARCH METHODS

We searched the following electronic databases: Cochrane Oral Health's Trials Register (to 16 May 2016), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, 2016, Issue 4), MEDLINE Ovid (1946 to 16 May 2016), Embase Ovid (1980 to 16 May 2016) and CancerLit via PubMed (1950 to 16 May 2016). We searched the metaRegister of Controlled Trials (to 10 February 2015), ClinicalTrials.gov (to 16 May 2016) and the World Health Organization (WHO) International Clinical Trials Registry Platform for ongoing trials (to 16 May 2016). We placed no restrictions on the language or date of publication when searching electronic databases.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that enrolled people with a diagnosis of oral leukoplakia and compared any treatment versus placebo or no treatment.

DATA COLLECTION AND ANALYSIS

We collected data using a data extraction form. Oral cancer development, demonstrated by histopathological examination, was our primary outcome. Secondary outcomes were clinical resolution of the lesion, improvement of histological features and adverse events. We contacted trial authors for further details when information was unclear. When valid and relevant data were available, we conducted a meta-analysis of the data using a fixed-effect model when we identified fewer than four studies with no heterogeneity. For dichotomous outcomes, we calculated risk ratios (RRs) and 95% confidence intervals (CIs). We assessed risk of bias in studies by using the Cochrane tool. We assessed the overall quality of the evidence by using standardised criteria (Grades of Recommendation, Assessment, Development and Evaluation Working Group (GRADE)).

MAIN RESULTS

We included 14 studies (909 participants) in this review. Surgical interventions, including laser therapy and cryotherapy, have never been studied by means of an RCT that included a no treatment or placebo arm. The included trials tested a range of medical and complementary treatments, in particular, vitamin A and retinoids (four studies); beta carotene or carotenoids (three studies); non-steroidal anti-inflammatory drugs (NSAIDs), specifically ketorolac and celecoxib (two studies); herbal extracts (four studies), including tea components, a Chinese herbal mixture and freeze-dried black raspberry gel; bleomycin (one study); and Bowman-Birk inhibitor (one study).We judged one study to be at low risk of bias, seven at unclear risk and six at high risk. In general, we judged the overall quality of the evidence to be low or very low, so findings are uncertain and further research is needed.Five studies recorded cancer incidence, only three of which provided useable data. None of the studies provided evidence that active treatment reduced the risk of oral cancer more than placebo: systemic vitamin A (RR 0.11, 95% CI 0.01 to 2.05; 85 participants, one study); systemic beta carotene (RR 0.71, 95% CI 0.24 to 2.09; 132 participants, two studies); and topical bleomycin (RR 3.00, 95% CI 0.32 to 27.83; 20 participants, one study). Follow-up ranged between two and seven years.Some individual studies suggested effectiveness of some proposed treatments, namely, systemic vitamin A, beta carotene and lycopene, for achieving clinical resolution of lesions more often than placebo. Similarly, single studies found that systemic retinoic acid and lycopene may provide some benefit in terms of improvement in histological features. Some studies also reported a high rate of relapse.Side effects of varying severity were often described; however, it seems likely that interventions were well accepted by participants because drop-out rates were similar between treatment and control groups.

AUTHORS' CONCLUSIONS

Surgical treatment for oral leukoplakia has not been assessed in an RCT that included a no treatment or placebo comparison. Nor has cessation of risk factors such as smoking been assessed. The available evidence on medical and complementary interventions for treating people with leukoplakia is very limited. We do not currently have evidence of a treatment that is effective for preventing the development of oral cancer. Treatments such as vitamin A and beta carotene may be effective in healing oral lesions, but relapses and adverse effects are common. Larger trials of longer duration are required to properly evaluate the effects of leukoplakia treatments on the risk of developing oral cancer. High-quality research is particularly needed to assess surgical treatment and to assess the effects of risk factor cessation in people with leukoplakia.

Metabolic syndrome and health-related behaviours associated with pre-oral cancerous lesions among adults aged 20-80 years in Yunlin County, Taiwan: a cross-sectional study

OBJECTIVES

To explore the associations of health-related behaviours, metabolic syndrome and risk factors in adults with pre-oral cancerous (POC) lesions in rural, disadvantaged communities with a high prevalence of oral cancer.

DESIGN

A cross-sectional observational study.

SETTING

Community-based health survey in the western coastal area of Yunlin County, Taiwan.

PARTICIPANTS

5161 adult residents participated in this study.

OUTCOME MEASURES

Assessed parameters included oral leukoplakia, oral submucous fibrosis, fasting blood glucose, triglycerides, high-density lipoprotein cholesterol, blood pressure and waist circumference. Statistical analyses included descriptive statistics, χ(2) tests and multivariate binary logistic regression.

RESULTS

A high percentage of participants were found to have metabolic syndrome (40%) and POC lesions (7.3%). Participants with POC lesions tended to be male (p<0.001), betel nut chewers (p<0.001) and cigarette smokers (p<0.001); have a low level of education (p<0.001); seldom undergo dental check-ups (p<0.01); irregularly participate in physical activity (p<0.01) and have metabolic syndrome (p<0.01).

CONCLUSIONS

Although male sex and disadvantaged socioeconomic status are non-modifiable factors associated with POC and metabolic syndrome in adults, several factors, notably health behaviours, are modifiable. Clinicians can reduce the incidence and consequences of POC by developing programmes for early detection, encouraging regular dental check-ups, and initiating individualised, health-promoting behaviour modification programmes for reducing risky behaviours associated with oral cancer.

Gene polymorphisms and oral cancer risk in tobacco habitués

Oral cancer incidence of 77,003 poses a major health concern in India, with 5-10 % tobacco habitués developing oral cancer. The current study examined the role of specific genomic variants in oral cancer. We examined five genomic variants represented as single nucleotide polymorphisms (SNPs) in genes associated with cell proliferation and cellular invasion. The SNPs rs2124437 (RASGRP3), rs1335022 (GRIK2), rs4512367 (PREX2), rs4748011 (CCDC3), and rs1435218 (LNX1) were analyzed in 500 histopathologically confirmed oral cancers and 500 healthy controls with a minimum of 10 years of tobacco usage. Allelic discrimination real-time PCR SYBR Green assay was used. The genotypic and allelic frequencies between cases and controls were analyzed using SPSS software (version 19) and odds ratio (OR) using Hutchon.net, indicating increased risk to oral cancers. A significant association of the SNPs in oral cancer was observed in RASGRP3 AA (rs2124437) (p < 0.000, OR 1.34, 95 % confidence interval (CI) 1.01-1.76), GRIK2 TT (rs1335022) (p = 0.008, OR 1.58, 95 % CI 1.23-2.03), PREX2 CC (p = 0.008, OR 1.56, 95 % CI 1.15-2.1), and TT (p < 0.000, OR 2.77, 1.68-4.57) genotypes, whereas the heterozygous genotypes showed higher frequencies in controls, i.e., GRIK2 CT (rs1335022) (p = 0.029, OR 0.68, 95 % CI 0.53-0.87) and PREX2 CT (p = 0.004, OR 0.49, 95 % CI 0.37-0.64), indicating protection. Coinheritance of the SNPs was associated with further increase in the risk. Thus, the SNP genotypes in the three genes, present singly or as a coinherited panel constituted "Predictive Biomarkers" indicating increased risk of oral cancer in tobacco habitués.

Clinical implications of epigenetic regulation in oral cancer

Oral cancer is a high incidence cancer which is of major public health concern in India being the most common cancer in males and fifth most common cancer in females in India, contributing to 26% of the global oral cancer burden. The major risk factors of oral cancer are tobacco, alcohol and high risk Human Papilloma Virus type 16/18. However, only 3-12% of the high risk individuals with dysplasia develop oral cancer. Thus, individual genomic variants representing the genomic constitution and epigenetic alterations play a critical role in the development of oral cancer. Extensive epigenetic studies on the molecular lesions including oncogenes, tumor suppressor genes, genes associated with apoptosis, DNA damage repair have been reported. The current review highlights epigenetic regulation with a focus on molecular biomarkers and epidrug therapy in oral cancer. Epigenetic regulation by hypermethylation, histone modifications and specific microRNAs are often associated with early events and advanced stages in oral cancer, and thus indicate epidrug therapy for intervention. The presence of epigenetic marks in oral lesions, cancers and tumor associated mucosa emphasizes indications as biomarkers and epidrugs with therapeutic potential for better patient management.

Malignant transformation of oral leukoplakia: a systematic review of observational studies

The aim of this systematic review was to ascertain the malignant transformation rate of oral leukoplakia and the associated risk factors.

METHOD

Published literature was searched through several search engines from 1960 to the end of December 2013. The inclusion criteria included 'leukoplakia', 'pre-cancer', 'malignant transformation', 'follow-up' and 'outcome'. Two reviewers extracted the data independently and also assessed the quality of evidence.

RESULTS

The search strategy resulted in 1032 abstracts or full-text articles, of which 24 met the inclusion criteria. There was much variation in the definitions used by the various authors in their original reports to define oral leukoplakia or in the criteria used to recruit their patients for follow-up. The estimated overall (mean) malignant transformation rate for the total population described in these 24 studies amounts to 3.5% (405/11423), with a wide range between 0.13% and 34.0%. Based on the evidence presented, the features that stand out as significant determinants contributing to malignant potential of OL include advanced age, female sex, leukoplakia exceeding 200 mm(2) , non-homogeneous type (eg. erythroleukoplakia) and the higher grades of dysplasia.

CONCLUSION

The review indicates that drawing meaningful evidence-based conclusions are difficult from retrospective studies of this nature. However, many of the determinants exposed in the review require further investigation by well-designed prospective studies.

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.

The use of light-based (optical) detection systems as adjuncts in the detection of oral cancer and oral potentially malignant disorders: a systematic review

INTRODUCTION

In recent decades, optical techniques utilising the principles of chemiluminescence and tissue autofluorescence have emerged to facilitate the early detection of any oral mucosal changes suspicious of cancer.

PURPOSE

To evaluate the effectiveness of devices that utilise the principles of chemiluminescence and tissue autofluorescence as adjuncts in the detection of oral cancer and oral potentially malignant disorders (OPMDs).

METHODS

A systematic review of the published literature to evaluate the effectiveness of the ViziLite(®) and ViziLite(®) Plus with toluidine blue, MicroLux™/DL and the VELscope™ as aids in the detection of oral cancer and OPMDs.

RESULTS

Twenty-five primary studies published between 2004 and 2013 satisfied our criteria for selection - 13 utilised chemiluminescence and 12 tissue autofluorescence. Some had utilised both study methods on the same population. Chemiluminescence shows good sensitivity at detecting any OPMDs and oral cancer. However, it preferentially detects leukoplakia and may fail to spot red patches. The additive use of toluidine blue may improve specificity. Tissue autofluorescence is sensitive at detecting white, red and white and red patches, and the area of fluorescence visualisation loss (FVL) often extends beyond the clinically visible lesion. However, in addition to OPMDs, VELScope may detect erythematous lesions of benign inflammation resulting in false-positive test results.

CONCLUSION

There is limited evidence for their use in primary care, and these tools are better suited to specialist clinics in which there is a higher prevalence of disease and where experienced clinicians may better discriminate between benign and malignant lesions.

Comparison of health-related quality of life of patients with different precancer and oral cancer stages

OBJECTIVES

Health-related quality of life (HR-QoL) informations are becoming an important tool for the treatment concept for cancer patients. The purpose of this study was to evaluate how the quality of life depends on the disease severity of pre- and oral cancer patients and which factors influence their quality of life.

MATERIALS AND METHODS

During this study, 106 patients with a premalignant oral lesion, 174 patients with oral squamous cell carcinoma (OSSC) as well as 21 patients with a recurrence of OSSC were asked about their oral health-related quality of life. Additionally, the UW-QOLv4 was used to record the psychological and clinical symptoms from which the patients of the three groups are suffering.

RESULTS

Significant differences with respect to oral HR-QoL of life between the groups could be evaluated. Patients with a recurrence have the lowest and patients with precancer the highest HR-QoL. Within the groups, there is a difference regarding the significance of the psychological factors. The lowest values were achieved for mood within all three groups. Anxiety is of key importance for the precancer group whereas appearance and activity are of importance for the patients having a tumor. The patients of the recurrence group are heavily affected by all factors.

CONCLUSIONS

The quality of life differs depending on the disease. The patients of the recurrence group have the lowest oral health-related quality of life for all aspects analyzed, and they are suffering the most with respect to the psychological dimensions of the UW-QOLv4.

CLINICAL RELEVANCE

The present study examined the quality of life depending on the severity of the disease of pre- and oral cancer patients and which factors significantly influenced their quality of life. The evaluated findings of relevant variables may have therapeutic relevance for the multidisciplinary treatment of oral cancer patients in the future.

Evaluation of MAGE-A expression and grade of dysplasia for predicting malignant progression of oral leukoplakia

The risk of the malignant transformation of oral leukoplakia (OLP) is difficult to predict by histopathology. Melanoma-associated antigen-A (MAGE-A) expression is restricted to malignant cells and may be useful for the more accurate estimation of the potential malignant transformation of pre-malignant lesions. The aim of the present study was to investigate whether the expression of MAGE-A can be used to predict the malignant transformation of OLP. Paraffin-embedded tissue samples of OLP from 74 patients followed-up for at least 5 years were included. A total of 24 progressing and 50 non-progressing OLP, 18 corresponding tumor and 30 healthy mucosa specimens were analysed for MAGE-A 1, 3, 4, 6 10 and 12 expression by nested real‑time RT-PCR and graded for dysplasia. In total, 46% of the progressing lesions expressed at least 1 out of the examined MAGE-A antigens, whereas no expression was detected in any of the non-progressing OLP and normal specimens. The correlation between malignant transformation and MAGE-A expression was statistically significant (p=0.00001). Furthermore, 42% of the progressing OLPs without dysplasia (D0) expressed at least 1 antigen. The correlation between the grade of dysplasia and MAGE-A staining in the malignant transformation group was not significant (p=0.08). The detection of at least 1 MAGE-A antigen may allow the identification of high-risk lesions that may progress into carcinoma with time. Therefore, the investigation of MAGE-A expression should be assessed in order to obtain a more accurate evaluation of the potential cancer risk of OLP.

Efficacy of oral brush cytology in the evaluation of the oral premalignant and malignant lesions

Objective:

In the present study, oral brush cytology of premalignant and malignant lesions was performed using tooth brush. The cytopathological diagnosis of brush cytology was compared with that of punch biopsy. The reliability of oral brush cytology using tooth brush was assessed in terms of sensitivity and specificity.

Materials and Methods:

A total of 67 patients, 32 premalignant lesions and other 35 frank oral carcinomas, were included in the study. All patients underwent oral brush cytology using a toothbrush followed by punch biopsy. Sensitivity, specificity, positive and negative predictive values were calculated. Cytopathology and histopathology of premalignant and malignant lesions were compared using Mann-Whitney U test. Inter- and intra-examiner reliability was calculated using Rank-correlation coefficient.

Results:

Two in premalignant group and five in malignant group were marked insufficient. 18% of cases were false negatives. The sensitivity, specificity, positive predictive value and negative predictive value were 77%, 100%, 100% and 38%, respectively. Statistical analysis showed P>0.05, suggesting that there is no significant difference between histopathology and brush cytology in assessing both premalignant and malignant lesions. Inter- and intra-examiner reliability were 99.22% and 99.77%, respectively.

Conclusion:

Brush cytology using a tooth brush is reliable and can be easily performed with less cost and discomfort to the patient. It is useful in those situations when a patient refuses to have a biopsy performed or when medically compromised patients would be exposed to unnecessary surgical risks. It can be used for screening for suspicious oral lesions, and may have applications in resource-challenged areas.

Use of endoscopy with narrow-band imaging system in evaluating oral leukoplakia

BACKGROUND

The purpose of this study was to analyze the relationship between clinical features of oral leukoplakia using endoscopy with broadband white light, narrow-band imaging (NBI) illumination, and histopathology, and to discuss the clinical relevance of the NBI system.

METHODS

Clinicopathologic data of patients receiving biopsy or excision after endoscopic examination for leukoplakia from April 2009 to December 2010 were reviewed and analyzed statistically.

RESULTS

A total 154 patients, 130 men and 24 women (average age, 52.60 ± 10.86 years) were enrolled. The correlation between intraepithelium papillary capillary loop (IPCL) classification and stepwise increased severity of pathology (Pearson's r = .88, R(2) = 0.78) was significantly better than that of broadband white light images (p < .001).

CONCLUSIONS

Flexible endoscopy can enhance detailed inspection of oral cavity mucosa and can be a powerful tool for examining oral leukoplakia. The IPCL patterns shown by NBI system can be helpful in detecting oral leukoplakia with higher grade dysplasia or invasive carcinoma.

Non-invasive measurement of the microvascular properties of non-dysplastic and dysplastic oral leukoplakias by use of optical spectroscopy

Differential Path-length Spectroscopy (DPS) was used to non-invasively determine the optical properties of oral leukoplakias in vivo. DPS yields information on microvascular parameters such as the mucosal blood content, the microvascular blood oxygenation and the average micro-vessel diameter as well as on tissue morphological parameters such as the scattering slope and scattering amplitude. DPS measurements were made on non-dysplastic and dysplastic oral leukoplakias using a novel fiber-optic probe, and were correlated to the histological outcome of biopsies taken from the same location. Our data show borderline significant increases in mucosal blood content in dysplastic lesions compared to non-dysplastic lesions, with no changes in microvascular oxygen saturation and light scattering signatures. These results suggest that dysplastic and non-dysplastic leukoplakias may be discriminated non-invasively in vivo through differences in their microvascular properties, if they can be reproducibly quantified in the presence of a variable thickness keratin layer that optically shields the mucosal layer.

MAGE-A antigens in lesions of the oral mucosa

Oral squamous cell carcinoma develops continuously out of predamaged oral mucosa. For the physician and pathologist, difficulties arise in distinguishing precancerous from cancerous lesions. MAGE-A antigens are tumor antigens that are found solely in malignant transformed cells. These antigens might be useful in distinguishing precancerous from cancerous lesions. The aim of this study was to verify this assumption by comparing MAGE-A expression in benign, precancerous, and cancerous lesions of the oral mucosa. Retrospectively, biopsies of different oral lesions were randomly selected. The lesions that were included are 64 benign oral lesions (25 traumatic lesions (oral ulcers), 13 dental follicles, and 26 epulis), 26 oral lichen planus, 123 epithelial precursor lesions (32 epithelial hyperplasia found in leukoplakias, 24 epithelial dysplasia found in leukoplakias, 26 erythroplasia with oral epithelial dysplasia, and 41 carcinomas in situ in erythroleukoplakias). The lesions were immunohistochemically stained with the poly-MAGE-A antibody 57B, and the results were compared. Biopsies of oral lichen planus, oral ulcers, dental follicles, epulis, and leukoplakia without dysplasia showed no positive staining for MAGE-A antigens. Leukoplakia with dysplasia, dysplasia, and carcinomata in situ displayed positive staining in 33%, 65%, and 56% of the cases, respectively. MAGE-A antigens were not detectable via immunohistochemistry in benign lesions of the oral mucosa. The staining rate of dysplastic precancerous lesions or malignant lesions ranged from 33% to 65%. The MAGE-A antigens might facilitate better differentiation between precancerous and cancerous lesions of the oral mucosa.

Polymorphisms at p53, p73, and MDM2 loci modulate the risk of tobacco associated leukoplakia and oral cancer

Polymorphisms at loci controlling cellular processes such as cell cycle, DNA repair, and apoptosis may modulate the risk of cancer. We examined the association of two linked polymorphisms (G4C14-A4T14) at p73 and one polymorphism (309G > T) at MDM2 promoter with the risk of leukoplakia and oral cancer. The p73 and MDM2 genotypes were determined in 197 leukoplakia patients, 310 oral cancer patients and in 348 healthy control subjects. The p73 GC/AT genotype increased the risk of leukoplakia (OR = 1.6, 95% CI = 1.1-2.3) and oral cancer (OR = 2.4, 95% CI = 1.7-3.3) but the 309G > T MDM2 polymorphism independently could not modify the risk of any of the diseases. Stratification of the study population into subgroups with different tobacco habits showed that the risk of the oral cancer is not modified further for the individuals carrying p73 risk genotype. However, leukoplakia patients with smokeless tobacco habit showed increased risk with combined GC/AT and AT/AT (OR = 3.0, 95% CI = 1.3-7.0) genotypes. A combined analysis was done with our previous published data on p53 codon 72 pro/arg polymorphism. Analysis of pair wise genotype combinations revealed increase in risk for specific p73-MDM2 and p73-p53 genotype combinations. Finally, the combined three loci analyses revealed that the presence of at least one risk allele at all three loci increases the risk of both leukoplakia and oral cancer.

Is dental care utilization associated with oral cavity cancer in a large sample of community-based United States residents?

OBJECTIVES

Cancer of the oral cavity and pharynx remains one of the 10 leading causes of cancer deaths in US. Besides smoking and alcohol consumption, there are no well-established risk factors. While poor dental care had been implicated, it is unknown if lack of dental care, implying poor dental hygiene predisposes to oral cavity cancer. This study aimed to assess the relationship between dental care utilization during the past 12 months and the prevalence of oral cavity cancer.

METHODS

A cross-sectional design of the National Health Interview Survey of Adult, noninstitutionalized US residents (n=30 475) was used to assess the association between dental care utilization and self-reported diagnosis of oral cavity cancer. Chi-square statistic was used to examine the crude association between the explanatory variable, dental care utilization and other covariates, while unconditional logistic regression was used to assess the relationship between oral cavity cancer and dental care utilization.

RESULTS

There were statistically significant differences between those who utilized dental care during the past 12 months and those who did not with respect to education, income, age, marital status, and gender (P<0.05), but not health insurance coverage (P=0.53). In addition, those who utilized dental care relative to those who did not were 65% less likely to present with oral cavity cancer, prevalence odds ratio (POR), 0.35, 95% confidence interval (CI), 0.12-0.98. Further, higher income, advanced age, people of African heritage, and unmarried status were statistically significantly associated with oral cavity cancer (P<0.05), but health insurance coverage, alcohol use, and smoking were not, P>0.05. After simultaneously controlling for the relevant covariates, the association between dental care and oral cavity cancer did persist but imprecise. Thus, when compared with those who did not use dental care, those who did were 62% less likely to be diagnosed with oral cavity cancer, adjusted POR, 0.38, 95% CI, and 0.13-1.10.

CONCLUSIONS

Among US adults residing in community settings, use of dental care during the past 12 months was marginally statistically significantly associated with oral cavity cancer, but clinically relevant in assessing oral cavity cancer prevalence in this sample. However, because of the nature of our data, which restricts temporal sequence, a large sample prospective study that may identify modifiable factors associated with oral cavity cancer development, namely poor dental care is needed.

1H NMR-based metabonomic and pattern recognition analysis for detection of oral squamous cell carcinoma

BACKGROUND

Metabonomic analysis has been increasingly used to monitor metabolic abnormalities in cells and their microenvironment in order to detect the cancer markers recently. We evaluated the feasibility of applying (1)H nuclear magnetic resonance ((1)H NMR) based metabonomic method in the early detection of the differences in the plasma from 3 groups, which were patients with oral squamous cell carcinoma (OSCC), patients with oral leukoplakia (OLK), and the healthy control group.

METHODS

(1)H NMR spectra were obtained from human plasma samples prior to spectral analysis. The obtained data were processed by both the unsupervised principal component analysis (PCA) and the supervised partial least squares discriminant analysis (PLS-DA) to find out the differences among the three groups.

RESULTS

PLS-DA analysis has revealed a good model to detect the NMR data that can differentiate the OSCC patients from the OLK patients and the controls using a test set.

CONCLUSION

The results indicated that the (1)H NMR-based metabonomic approach is a feasible and efficient method for differentiating the OSCC patient's plasma from the healthy controls. As a potential novel strategy and a more convenient technique, it deserves a further evaluation for an early detection of oral cancer.