Oral exfoliative cytology: review of methods of assessment

A brief review of cytology in dentistry

Oral cytology is a non-invasive adjunctive diagnostic tool with a number of potential applications in the practice of dentistry. This brief review begins with a history of cytology in medicine and how cytology was initially applied in oral medicine. A description of the different technical aspects of oral cytology is provided, including the collection and processing of oral cytological samples, and the microscopic interpretation and reporting, along with their advantages and limitations. Applications for oral cytology are listed with a focus on the triage of patients presenting with oral potentially malignant disorders and oral mucosal infections. Furthermore, the utility of oral cytology roles across both expert (for example, secondary oral medicine or tertiary head and neck oncology services) and non-expert (for example, primary care general dental practice) clinical settings is explored. A detailed section covers the evidence-base for oral cytology as a diagnostic adjunctive technique in both the early detection and monitoring of patients with oral cancer and oral epithelial dysplasia. The review concludes with an exploration of future directions, including the integration of artificial intelligence for automated analysis and point of care 'smart diagnostics', thereby offering some insight into future opportunities for a wider application of oral cytology in dentistry.

Cytomorphometric Study of Changes in Buccal Mucosal Cells in Alcoholics

Background:

Chronic alcohol consumption carries a high risk for oral and pharyngeal cancers among persons who have never smoked. Excessive alcohol consumption displays cytogenetic changes in oral mucosa cells. Cytomorphometric analysis of oral mucosal cells helps in the early detection of cytomorphological transformations in alcoholics before and after the onset of carcinoma.

Materials and Methods:

A prospective, hospital-based, comparative study was done after written informed consent. Smears were obtained from the clinically normal buccal mucosa of 102 randomly selected alcoholic patients attending the medicine outpatient department aged above 25 years who consumed a minimum of 45 ml alcohol per day for at least 10 years and of 102 nonalcoholics as control. The slides were immediately fixed in absolute methanol and stained by the Papanicolaou (Pap) staining technique. PAP-stained smears were examined under the light microscope. Using the image J 1.47 image analysis software, a morphometric analysis of around 50 cells/case was done.

Results:

A statistically significant increase in mean cytoplasmic area (P < 0.001), mean nuclear area (P < 0.01), and cell-to-nuclear parameter ratio (P < 0.001) was seen in the alcohol group in comparison with the control group.

Conclusion:

Prolonged consumption of alcohol produces cytomorphometric changes in buccal mucosal cells before the onset of premalignant lesions.

Assessment and comparison of nuclear changes seen in gingivitis and periodontitis using fluorescent microscopy

INTRODUCTION AND OBJECTIVES

The objective of this study was to observe the evolution of genotoxicity (micronucleation, binucleation and multinucleation) from normal to periodontally compromised gingival epithelium (gingivitis and periodontitis) and to compare the severity of damage.

METHODS AND MATERIAL

45 participants formed 3 different categories; a control group of 15 healthy subjects, 15 subjects with gingivitis and 15 with chronic periodontitis. Smears were collected from all the gingiva and stained with acridine orange stain. A total of 500 cells were evaluated under fluorescent microscopy for nuclear abnormalities such as micronuclei, binucleation and multinucleation. The statistical analysis used was one way ANOVA and posthoc Tukey test.

RESULTS AND CONCLUSION

A statistically significant difference was observed when the age of the 3 groups were compared (p=0.002); the control group were younger than those with chronic periodontitis or gingivitis. With respect to genotoxic changes, the differences for binucleation (p=0.002) and multinucleation (p<0.001) were statistically significant thus suggesting advanced damage in the nucleus. Such changes in genotoxicity could be of help to a clinician in determining prognosis.

Toward early diagnosis of oral cancer: Diagnostic utility of cytomorphological features, a pilot study

Introduction:

Early detection of oral cancer is one of the most efficient ways to reduce the high mortality from this disease because of the ready accessibility of the oral cavity. We need to devise urgent diagnostic tools to detect early oral premalignant and malignant lesions.

Aim:

The aim of the present study was to grade the oral lesions in an attempt toward developing a novel cytological grading system. Further, morphometric analysis of cellular parameters was also performed to compare their significance in differentiating benign from malignant lesions.

Materials and Methods:

The present study was conducted at a tertiary care hospital catering to the low socioeconomic population. Patients presenting in the various Out Patient Departments with suspicious oral lesions were evaluated by cytology in the Department of Pathology.

Results:

A total of 72 patients were evaluated with a mean age of 43.54 ± 10.35 years. The involvement of the buccal mucosa was the most common site of oral lesions. Cytologically, the lesions were graded according to the oral/oro-pharyngeal cytology grading system into grades A to F. Cyto-morphometric analysis showed an increasing trend in mean nuclear diameter from benign to malignant cases while the mean cytoplasmic diameter decreased, value of P < 0.05 was observed indicating a statistically significant difference between the two groups.

Conclusions:

Cytological features of pleomorphism are a unique feature in oral carcinoma reflecting intracellular alterations in cells. Grading of lesions according to cytological characteristics can be helpful in standardizing the reporting of the oral lesion. However, our study was restricted by limited data; we emphasize more extensive studies to assess the usefulness and applicability of such a grading system. We also conclude that the use of cytomorphometry can improve the diagnostic reliability of exfoliative cytology.

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.

Evaluation of an innovative oral brush for potential applications using liquid based cytology

The present study was conducted to assess the applicability of liquid-based cytology (LBC) using an innovative oral brush, Orcellex. Fifty healthy volunteers were recruited. From each subject, four samples were collected using "Orcellex" from apparently normal oral mucosal sites. A plastic spatula was also used to obtain an additional sample. Data on the tolerability and acceptability of the Orcellex were collected from the subjects, together with assessments of the adequacy of LBC slide preparations for cellularity, preparation quality, and the types of cells observed. The Orcellex brush was well accepted by the volunteers, who reported relatively little pain. Orcellex brush LBC preparations were of good quality in terms of cell morphology and staining, with a clean background. Only two smears (2/200; 1%) were found to be inadequate due to low cellularity. All of the plastic spatula LBC preparations were inadequate. Representative cells from all layers of the different oral epithelia examined were documented. Oral liquid-based cytology using the Orcellex brush may have considerable potential for early detection of oral cancer and precancer.

Cytomorphometric analysis of gingival epithelium and buccal mucosa cells in type 2 diabetes mellitus patients

BACKGROUND

The global prevalence of type 2 diabetes continues to rise. Interest has been increasing recently in noninvasive diagnostic procedure. Hence, an attempt has been made by the present study to analyze the changes in cytomorphometry in exfoliated buccal and gingival mucosa cells in type 2 diabetic patients.

AIM

The aim of this study was to analyze the cytomorphometric changes in exfoliated cells of gingiva and buccal mucosa as an adjunct to diagnosis of diabetes.

MATERIALS AND METHODS

In the present study, fifty known type 2 diabetic patients were taken as study group, and the control group was comprised of fifty healthy individuals. Smear was prepared from buccal mucosa and gingival epithelium of both study and control groups and was stained by rapid Papanicolaou (Pap) stain. Stained smears were subjected to cytomorphometric analysis using Lynx Biolux (Lawrence and Mayo) image analysis software. In each Pap smear, 100 cells were evaluated for nuclear area (NA), cytoplasmic area (CA) and cytoplasm to nuclear ratio (CNR).

RESULTS

Mean NA was significantly higher (P < 0.05) in study group whereas mean CA did not exhibit any statistically significant difference (P > 0.05). The mean CNR was significantly lower in the study group (P < 0.05).

CONCLUSION

This study contributes to the general understanding of the alterations in the cellular pattern of buccal and gingival mucosa cells in diabetic patients and can be used as an additional tool to aid in the evaluation of oral mucosal alterations in diabetes mellitus.

Multimodal characterization of radiologically detectable lung lesions

Diagnosing radiologically detectable lung lesions on the basis of cyto/histopathological staining often suffers from ambiguity, leading to faulty detection of lung diseases, especially cancer. Present study attempted to perform a multimodal characterzation of clinical samples from patients with radiologically detected lung lesions, in order to classify diseases with higher precision. The study included analysing nuclear morphometric and intensity based differences between benign and malignant lung lesions in a quantitative way. Simultaneous analysis of serum samples taken from similar sets of patients was performed by Fourier transform infra red (FTIR) spectroscopy which provided differential global biochemical insights of normal and diseased states. Both nuclear and serum biochemical features were helpful in accomplishing high classification accuracy in distinguishing benign and different malignant cases.

Abnormal Nuclear Variations in Response to Radiotherapy- As a Tool in Treatment Planning and Assessment of Prognosis

INTRODUCTION

The treatment approaches for oral squamous cell carcinoma (OSCC) include single management with surgery, radiotherapy, along with chemotherapy or various combinations of these modalities. The estimation of radio sensitivity of individual tumours is essential for planning the optimum radiation schedule for each patient. Assessment of radiation induced histo morphological changes in the nucleus is a known marker of radiosensitivity.

AIM

The aim of this study was to establish the relationship between nuclear changes with radiation dose and to investigate the prospect of utilizing them as an assay to predict tumour response to radiotherapy in oral cancers.

MATERIALS AND METHODS

The present study included 50 patients (age range of 30-65yrs) with histopathologically confirmed squamous cell carcinoma of oral mucosa and being treated by radiotherapy alone with a radiation dose schedule of 4, 14, 24 and 60 Gy respectively at 2(nd), 7(th), 12(th) and 30(th) day. From the included patients, smear of the buccal mucosa was collected and was air dried and fixed with methanol. The Nuclear changes of Micronucleus (MN), Nuclear Budding (NB) and Multinucleation (MNU) were evaluated under the bright field microscopy after staining with Giemsa and May-Grunwald's stain.

RESULTS

Out of the 50, 37(74%) were males and 13(26%) were females (Ratio 3:1). The mean percentage increase of MN and MNU were found to be statistically significant (p=0.001) when compared with pre-treatment day. Similar findings were seen with NB, except between pretreatment and after 14 Gy (p-0.110). In the present study the measurement of relative increment index done in respect to all nuclear abnormalities show a sustained increase with increasing dosage of radiation.

CONCLUSION

The present study, was undertaken to explore the possibility of establishing a relationship between the frequencies of nuclear abnormalities in patients with oral cancer with applied dosage and duration of radiotherapy. The progressive increase in Micronucleus and Multinucleation indices with increasing dose of radiation proves that these parameters can be used as indicators for assessing the response of tumour for radiotherapy. These parameters can be used as prognostic indicator in oral carcinoma cases undergoing radiotherapy.

'Cytology-on-a-chip' based sensors for monitoring of potentially malignant oral lesions

Despite significant advances in surgical procedures and treatment, long-term prognosis for patients with oral cancer remains poor, with survival rates among the lowest of major cancers. Better methods are desperately needed to identify potential malignancies early when treatments are more effective.

OBJECTIVE

To develop robust classification models from cytology-on-a-chip measurements that mirror diagnostic performance of gold standard approach involving tissue biopsy.

MATERIALS AND METHODS

Measurements were recorded from 714 prospectively recruited patients with suspicious lesions across 6 diagnostic categories (each confirmed by tissue biopsy -histopathology) using a powerful new 'cytology-on-a-chip' approach capable of executing high content analysis at a single cell level. Over 200 cellular features related to biomarker expression, nuclear parameters and cellular morphology were recorded per cell. By cataloging an average of 2000 cells per patient, these efforts resulted in nearly 13 million indexed objects.

RESULTS

Binary "low-risk"/"high-risk" models yielded AUC values of 0.88 and 0.84 for training and validation models, respectively, with an accompanying difference in sensitivity+specificity of 6.2%. In terms of accuracy, this model accurately predicted the correct diagnosis approximately 70% of the time, compared to the 69% initial agreement rate of the pool of expert pathologists. Key parameters identified in these models included cell circularity, Ki67 and EGFR expression, nuclear-cytoplasmic ratio, nuclear area, and cell area.

CONCLUSIONS

This chip-based approach yields objective data that can be leveraged for diagnosis and management of patients with PMOL as well as uncovering new molecular-level insights behind cytological differences across the OED spectrum.

Evaluation of Various Nuclear Cytological Changes in Normal Buccal Mucosa and Peritumoural Area in Patients with Oral Squamous Cell Carcinoma Receiving Concomitant Chemoradiotherapy

Objectives. To evaluate the role of serial cytological assay in calculating the nuclear response of contralateral normal buccal mucosa and peritumoural area of squamous cell carcinoma of oral cavity in patients receiving fractionated radiotherapy (RT) and chemotherapy. Materials and Methods. This prospective, nonrandomized study was comprised of 76 histologically confirmed cases of oral squamous cell carcinoma on cyclical chemoradiation treatment. Chemoradiosensitivity was evaluated using serial scrape smears taken before and after immediate exposure to CCRT, at 17th day of CCRT (mid of treatment), and at the end of treatment. The nuclear changes, such as multinucleation, micronucleation, karyorrhexis, karyolysis, nuclear budding, prominent nucleoli, and binucleation occurring in both irradiated cancer cells and contralateral normal buccal mucosa, had a statistically significant dose related increase with concomitant chemoradiotherapy (p < 0.05). Conclusion. We recommend regular use of serial cytological assay during CCRT as it may prove to be a valuable tool for assessment of chemoradiosensitivity and persistence of tumour/dysplastic cells after radiotherapy.

Effects of immunosuppressive drugs on oral mucosa in patients with Behçet's disease: cytomorphological and cytopathological assessment

BACKGROUND/AIM

The aim of this study was to investigate cytomorphological and cytopathological changes in oral exfoliated smears collected from immunosuppressed patients with Behçet's disease (BD) using stereological methods.

MATERIALS AND METHODS

For cytomorphometric analysis, mucosal cell smears were obtained from the buccal mucosa and the floor of the mouths of BD patients treated with immunosuppressive drugs and from healthy volunteers. All mucosal smears from the patients and the healthy volunteers were stained using the Papanicolaou method and examined cytopathologically under light microscopy and cytomorphologically via the stereological nucleator method.

RESULTS

The cytomorphological analysis revealed 3 types of mucosal cells, with numbers of particularly pink cells lower in the aphthous areas of the patients with BD compared to the healthy controls (P < 0.05). The nuclear volumes (NVs) and cytoplasmic volume (CVs) were significantly higher in the BD patients (P < 0.05), but the NV/CV ratio was higher only in the drug-use patient groups (P > 0.05). There was lower apoptotic activity in the nondrug-use patients with BD and in the immunosuppressive-taking BD patients.

CONCLUSION

The findings suggest that quantifiably morphological and morphometric changes in oral mucosa can be detected by stereological techniques. Changes in these parameters may indicate malignant transformation in the oral mucosa.

A cytomorphometric analysis of oral mucosal changes in tobacco users

AIM

Tobacco use is the major cause of oral cancer, which is the sixth most common form of malignancy globally. Even in the absence of clinical manifestations, early changes in the oral mucosa can be detected microscopically by exfoliative cytology. The present study aimed to study and compare the cellular changes in the oral mucosa of tobacco users using cytomorphometry.

MATERIALS AND METHODS

A total of 80 subjects were included: 20 without any tobacco use habits, 20 tobacco chewers, 20 smokers, and 20 mishri users. Smears were collected from each subject, fixed, and stained using Papanicolaou stain. All slides were evaluated for nuclear and cytoplasmic changes using image analysis software.

RESULTS

Statistically significant decrease in cytoplasmic area and an increase in nuclear area and nuclear-cytoplasmic ratio were observed in tobacco users.

CONCLUSION

Tobacco in any form causes significant cellular changes, which could be the earliest indicators of developing malignant pathology. Exfoliative cytology can be used to detect such changes.

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.

Exfoliative cytology of buccal squames: A quantitative cytomorphometric analysis of patients with diabetes

BACKGROUND

Diabetes is a third leading cause of mortality and morbidity in the world. Diabetes is one of the most common endocrine metabolic disorders and its prevalence has been increasing worldwide. Oral exfoliative cytology may be a more appropriate adjunctive diagnostic tool in conditions like diabetes mellitus, where the invasive techniques lose viability.

AIMS

The purpose of this study is to analyze the cytomorphometric changes in the exfoliated cells of the oral mucosa, as an adjunct to the diagnosis of diabetes.

MATERIALS AND METHODS

Smears were taken from the buccal mucosa of 30 diabetes patients (study group) and 30 healthy individuals (control group). All the smears were stained with rapid Papanicolaou stain (PAP). In the PAP smears, the nuclear area (NA), cytoplasmic area (CA), and cytoplasmic-to-nuclear ratio (CNR) were evaluated for 50 cells in each smear, using the Image Analysis Software (Magnus Pro™) and research microscope (Lawrence and Mayo™).

RESULTS

The results showed that the mean NA was significantly higher (P < 0.001) in the study group, whereas, the mean CA did not exhibit a statistically significant difference (P > 0.001). The mean CNR was significantly lower in the study group (P < 0.001).

INTERPRETATION AND CONCLUSION

The results associated with the clinical observations suggest that diabetes can produce morphological and functional alterations in the oral epithelial cells, detectable by microscopic and cytomorphometric analysis using exfoliative cytology, which can be used in the diagnosis of the disease.

Exfoliative cytology as a tool for monitoring pre-malignant and malignant lesions based on combined stains and morphometry techniques

BACKGROUND

Prevention and early diagnosis have the greatest potential for public health and are the most effective method in the long-term to control oral cancer. The aim was to apply PAP staining together with AgNOR staining and morphometric analysis in oral exfoliative cytology, to determine the sensitivity and specificity of these methods in the detection of malignant changes for the purposes of both initial population monitoring and follow-up.

METHODS

AgNOR, Papanicolau, and morphometric tests were conducted in samples of patients with oral cancer, oral potentially malignant disorders and controls (opposite side of lesions). Specificity and sensitivity values for each stain method and the curve under ROC area were estimated.

RESULTS

The diagnostic variables which allowed greatest accuracy in identifying malignancy relative to the healthy control were cluster (76.92%), satellite (75.64%), and total (90%). The diagnosis was seen to be associated with PAP and total AgNOR, total AgNOR and PAP, total AgNOR and satellites and clusters, and total AgNOR nuclear area/cytoplasmic area ratio.

CONCLUSIONS

The total number of AgNOR is a reliable marker for detecting neoplastic cells; this method increases sensitivity and specificity by decreasing the likelihood of false negatives or positives, as the accuracy obtained was 90%. It is also a low-cost, non-invasive, simple methodology that can be recommended to help the early detection of oral cancer and monitoring of patients with a first diagnosis of cancer.

Oral rinse as a simpler approach to exfoliative cytology: a comparative study

BACKGROUND

Oral rinse is a novel method that can be used to detect dysplasia in potentially malignant disorders and malignant oral lesions in resource challenged areas. A study was undertaken to compare the quality of the normal smears prepared with the oral rinse and that of the wooden tongue spatula.

MATERIAL AND METHODS

One hundred five normal subjects were selected for the study. Two smears were prepared from clinically normal mucosa using an oral rinse and further two smears were scraped from clinically normal buccal mucosa using a wooden spatula.

STATISTICAL ANALYSIS

The smears were graded for cell yield, dispersion and cellular clarity on a three-point scale by two observers. The results were analyzed using Mann Whitney non parametric test.

RESULTS

The Oral rinse was found to be significantly more efficient than the wooden spatula, in terms of cell yield (p<0.0001), cell dispersion (p =.0052) and cellular detail (p<0.0001).

CONCLUSION

The study showed that the Oral rinse is an effective method for use in exfoliative cytology of normal oral mucosa.

Brush biopsy with DNA-image cytometry: a useful and noninvasive method for monitoring malignant transformation of potentially malignant oral disorders

Oral and pharyngeal cancer is the sixth most common cancer worldwide, the 5-year survival rate has not yet increased. A key factor in rates not having improved is the lack of early detection. This study was undertaken to estimate the diagnostic accuracy of brush biopsy with DNA-image cytometry (a noninvasive method) for potentially malignant oral disorders compared with tissue biopsy pathology in China. Exfoliative cells were obtained using a cytobrush cell collector from oral mucosa of 52 subjects, followed by scalpel biopsy from the same region. Nuclear DNA contents (ploidy) were measured after Feulgen restaining, using an automated DNA image cytometer. Exfoliative cytology with DNA-image cytometry and histopathological diagnosis were performed separately at different institutions. Histological investigation was considered the gold standard. We reported that the sensitivity of DNA aneuploidy for the detection of cancer cells in potentially malignant oral disorders was 86.36 %, its specificity was 90.00 %, its positive predictive value was 86.36 %, and its negative predictive value was 90.00 %. Brush biopsy with DNA-image cytometry is a useful method for monitoring potentially malignant oral disorders.

Cytomorphometric analysis of oral buccal mucosal smears in tobacco and arecanut chewers who abused with and without betel leaf

BACKGROUND

Tobacco in any form (smoking or chewing), arecanut chewing, and alcohol are considered to be the major extrinsic etiological factors for potentially malignant disorders of the oral cavity and for squamous cell carcinoma, the most common oral malignancy in India. An increase in nuclear diameter (ND) and nucleus-cell ratio (NCR) with a reduction in cell diameter (CD) are early cytological indicators of dysplastic change. The authors sought to identify cytomorphometric changes in ND, CD, and NCR of oral buccal cells in tobacco and arecanut chewers who chewed with or without betel leaf.

METHODS

Participants represented 3 groups. Group I consisted of 30 individuals who chewed tobacco and arecanut with betel leaf (BQT chewers). Group II consisted of 30 individuals who chewed tobacco and arecanut without betel leaf (Gutka chewers). Group III comprised 30 apparently healthy nonabusers. Cytological smears were prepared and stained with modified-Papanicolaou stain.

RESULTS

Comparisons between Groups I and II and Groups II and III showed that ND was increased, with P values of .054 and .008, respectively, whereas a comparison of Groups I and III showed no statistical significance. Comparisons between Groups I and II and Groups II and III showed that CD was statistically reduced, with P values of .037 and <.000, respectively, whereas comparison of Groups I and III showed no statistical significance. Comparisons between Groups I and II and groups II and III showed that NCR was statistically increased, with P values of <.000, whereas a comparison of Groups I and III showed no statistical significance.

CONCLUSIONS

CD, ND, and NCR showed statistically significant changes in Group II in comparison with Group I, which could indicate larger and earlier risk of carcinoma for Gutka chewers than in BQT chewers.

Short-term exposure to UV-A, UV-B, and UV-C irradiation induces alteration in cytoskeleton and autophagy in human keratinocytes

Ultraviolet radiation (UV) induces a series of morphological and ultrastructural alterations in human epidermis. Alterations observed in irradiated keratinocytes in morphological studies done before were cell retraction with loss of intercellular interactions, surface blebbing, and eventually cell death by apoptosis. The aim of this study was to investigate effect of UV-A, UV-B, and UV-C irradiation on the cytoskeleton of human keratinocytes. Keratinocytes were obtained by exfoliative scrubbing procedure from buccal mucosa of healthy individuals, and treated with UV-A, UV-B, and UV-C radiation. Afterward, treated cell were labeled with anti-alfa-tubulin and anti-human-cytokeratin and analyzed by light and confocal microscopy. The intensity of the cytokeratin labeling was found to be much higher in all irradiated cells than in control cells as observed by light microscope and measured with the Image J program. This measurement showed that with the decrease in the wavelengths of UV irradiation the intensity of the labeling of cells increases. Although the authors expected to find the collapse of microtubules toward the cell nucleus or their rearrangement in UV-treated cells, these alterations were not verified on cell smears labeled with anti-alfa tubulin observed by confocal microscope. When they used electron microscopy to examine in more detail the morphology of irradiated cells, they did not find apoptotic cells, but found features of autophagy in UV-treated keratinocytes. The authors assume that autophagy found as a result of UV radiation of human keratinocytes acts as a cytoprotective mechanism against UV-induced apoptosis.

Looking in the mouth for noninvasive gene expression-based methods to detect oral, oropharyngeal, and systemic cancer

Noninvasive diagnosis, whether by sampling body fluids, body scans, or other technique, has the potential to simplify early cancer detection. A classic example is Pap smear screening, which has helped to reduce cervical cancer 75% over the last 50 years. No test is error-free; the real concern is sufficient accuracy combined with ease of use. This paper will discuss methods that measure gene expression or epigenetic markers in oral cells or saliva to diagnose oral and pharyngeal cancers, without requiring surgical biopsy. Evidence for lung and other distal cancer detection is also reviewed.

Preclinical alterations of oral epithelial cells in contact with orthodontic appliances

AIM

This study evaluated the behavior of oral epithelial cells in contact with orthodontic appliances.

METHODS

Oral epithelial cells of clinically normal buccal mucosa were obtained by liquid-based exfoliative cytology from 22 orthodontic patients. The following regions were evaluated: a) oral mucosa exposed to friction from orthodontic brackets; b) oral mucosa exposed to friction from the tube on the orthodontic band, and c) oral mucosa not exposed to friction (control area). Nuclear (NA) and cytoplasmic (CA) areas and NA/CA ratio were assessed by an image analysis system. Cell morphology and cellularity were also analyzed by Papanicolaou technique.

RESULTS

The NA of the cells in contact with orthodontic brackets and bands were smaller than the control area. Cells in contact with the brackets showed the greatest reduction in CA in comparison with the cells subjected to friction from the tube, and the control group. Smears classified as type I predominated in all regions analyzed, although type II were predominant, together with superficial epithelial cells, mainly in the oral mucosa in contact with the band tube.

CONCLUSION

Preclinical alterations in the epithelial cells of oral mucosa, caused by orthodontic appliances, are reduction in NA, increase in cell keratinization and inflammatory features, especially in the band tube area.

Differential expression of TLR-2 and TLR-4 in the epithelial cells in oral lichen planus

OBJECTIVE

Oral lichen planus (OLP) is a chronic inflammatory condition of the mucosa mediated by a complex signalling network between the keratinocytes and the sub-epithelial lymphocytes. Since OLP occurs in constantly renewing epithelium continuously exposed to commensals, we hypothesised that the epithelial cell microflora interactions may mediate the persistent inflammation. By virtue of their ability to respond to most oral commensal microorganisms, the toll like receptor-2 (TLR-2) and TLR-4 are the most widely investigated receptors in oral diseases. The overall objective of this study was to investigate the role of TLR-2 and TLR-4 in OLP.

DESIGN

Systemically healthy OLP and control subjects were recruited after obtaining the institutional review board approval. Expression of TLR-2 and TLR-4 proteins and transcripts in the tissue epithelium and in the epithelial cells isolated from saliva were determined by immunohistochemistry and quantitative real-time polymerase chain reaction respectively.

RESULTS

The tissue epithelium and the salivary epithelial cells expressed reduced TLR-2 and increased TLR-4 proteins and transcripts in OLP. The salivary epithelial cells from OLP subjects secreted elevated IL-12. However, upon stimulation with bacterial lipopolysaccharide the epithelial cells from OLP exhibited a mixed Th1 (IL-12) and Th2 (IL-4) response. Presence of dexamethasone significantly reduced inflammatory cytokines in the in vitro stimulated cultures of salivary epithelial cells from OLP subjects.

CONCLUSION

Collectively, our data support a critical role for the host-microbial interactions in the OLP pathogenesis. The potential use of exfoliated oral epithelial cells in saliva for functional analysis exponentially increases its value as biological specimen for clinical research.

Quantitative cytomorphometric analysis of exfoliated normal gingival cells

Background:

The use of oral exfoliative cytology as a diagnostic aid accentuates the need for establishing an accurate baseline, thereby enabling the comparison of abnormal oral tissue with established baseline.

Aims and Objective:

To detect any changes in the nuclear area (NA), cytoplasmic area (CA), and nuclear:cytoplasmic ratio (N:C ratio) values for clinically normal gingival smears in relation to age and sex of apparently healthy subjects.

Materials and Methods:

Gingival smears were collected from 80 (40 male, 40 female) apparently healthy subjects belonging to the age group of 0–20, 21–40, 41–60, and more than 60 years. Smear slides were fixed by using spray fixative. The smears were stained using Papanicolaou procedure. The cytoplasmic and NAs were measured using image analysis software. Statistical analysis of the data was done using one-way ANOVA with Tukey–HSD procedure and Student's t test.

Results:

The result showed that there was a significant difference (P<0.001) in NA, CA, and N:C in males of different age groups. There was a significant difference (P<0.001) in NA, CA, and N:C in females of different age groups. The difference in N:C between males and females was significant (P<0.001) in all the groups. The difference in NA, CA, and N:C with age irrespective of gender was significant (P<0.05). There was a significant difference (P<0.05) between males and females with respect to NA, CA, and N:C irrespective of age.

Conclusion:

Age-and sex-related alterations were observed in gingival smears, which could be a baseline for these variables to compare identical measurements, made on pathologic smears of oral premalignant and malignant lesions.

Morphologic and cytomorphometric analysis of exfoliated buccal mucosal cells in diabetes patients

BACKGROUND

It is now known that the disease process of diabetes has effects on various tissues of the body. The following study was done to analyze the effects of diabetes on oral tissues.

AIMS

To study the morphology and cytomorphometry of the cells obtained in cytologic smears from the buccal mucosa of diabetic patients.

MATERIALS AND METHODS

Smears were obtained from clinically normal buccal mucosa of 50 randomly selected diabetic patients attending the diabetic clinic and the out-patient department and of five healthy subjects as control. Smears were stained using Papanicolaou method, and using a micrometer mean values of nuclear diameter (ND), cell diameter (CD), cytoplasmic diameter (CyD) and nucleus: cytoplasm ratio (N: C ratio) were obtained for each patient. Diabetic patients were divided into four groups based on the glycosylated hemoglobin (GHb) values for comparison.

STATISTICAL ANALYSIS USED

Student's T-test and Fisher's F-test.

RESULTS

Statistically significant increase in ND (P=0.0367) was found in diabetic patients compared to controls. Degree of glycemic control significantly affected ND (P=0.0042) and N: C ratio (P=0.0055). In general, as the severity of diabetes increases, ND and N: C ratio rise gradually.

CONCLUSIONS

Diabetes produces definite morphologic and cytomorphometric changes in the buccal mucosa of patients. However, further research in this direction is indicated, to analyze the significance of these findings as a tool for diabetes detection, as well as to obtain deeper insights into its effects on various tissues.

Non-computer-assisted liquid-based cytology for diagnosis of oral squamous cell carcinoma

The development of oral squamous cell carcinoma (OSCC) occasionally follows the neoplastic progression of other premalignant lesions. Although biopsy is the definitive diagnostic method, liquid-based cytology is an adequate method for screening suspicious lesions. We compared liquid-based cytology to histology for diagnosis of OSCC in patients with oral lesions that raised clinical suspicion of malignancy. Our sample consisted of 48 patients. Cytological samples were obtained by scraping the lesion superficially using Cytobrush®. We conducted cytological and histopathological evaluation of all preparations. We estimated sensitivity and specificity levels as well as positive and negative predictive values. The degree of inter-observer agreement for both methods was assessed using the kappa index. Twenty-eight (58.3%) of the cases finally were diagnosed with OSCC and 20 (41.7%) were determined to be premalignant lesions. We observed eight false negatives and no false positives; OSCC prevalence was 56.5%. The values for diagnostic indices were: sensitivity, 69% (CI 95%, prevalence 51.87); specificity, 100%; positive predictive value, 100%; negative predictive value, 71% (CI 95% 54.82). A kappa index of 0.622 (CI 95% 0.93, 0.39) was observed.

Exfoliative cytology for diagnosing oral cancer

Exfoliative cytology is a minimally invasive technique for obtaining oral cell specimens from patients for diagnostic purposes. Classical applications of oral cytology studies, such as oral candidiasis, have been extended to include oral precancerous and cancerous lesions. A number of analytical methods are available for studying cytology specimens. The development of molecular analysis techniques, the oral cancer etiopathogenic process, and improvements in liquid-based exfoliative cytology are leading to renewed interest in exfoliative cytology. Results sometimes are disputed, so the aim of our review was to clarify the applicability of exfoliative cytology to the diagnosis of oral precancerous and cancerous lesions.

Actinic lesions in fishermen's lower lip: clinical, cytopathological and histopathologic analysis

INTRODUCTION

Actinic cheilitis (AC) is considered to be a pre-malignant lesion or an incipient and superficial form of lip squamous cell carcinoma. It is commonly found in individuals whose occupational activities are related to chronic sun exposure and the definitive diagnosis is performed with biopsy. Although Exfoliative cytology has been used as a screening procedure to evaluate cancer of the oral cavity no studies have proposed the use of exfoliative cytologic analysis to evaluate and diagnose AC.

OBJECTIVE

The purpose of this study was to evaluate lower lip lesions on fishermen related to chronic solar exposure using clinical, cytologic and histopathologic analyses.

PATIENTS AND METHODS

Smears taken from the vermilion of the lower lips of 125 fishermen and 30 control individuals were subjected to cytologic analysis.

RESULTS

The harvested cells were sufficient for cytologic analysis in 83.2% of the samples. Sixteen fishermen exhibited prominent lower lip lesions that justified biopsy and histological studies. In total, 4 specimens were malignant (3.2%), and 12 displayed epithelial dysplasia, demonstrating that the prevalence of epithelial dysplasia and malignant lesions was high among the fishermen population. These conditions were strongly associated with infiltration and blurring of the vermilion margin of the lower lip.

CONCLUSION

The cytologic analysis was not useful for detecting epithelial dysplasia or malignant alterations.

Assessment of oral cytological changes associated with exposure to chemotherapy and/or radiotherapy

BACKGROUND

Death from cancer is high in Sudan, with low survival rates, as most of the patients present with advanced disease. Most patients receive high and repeated doses of radiotherapy or chemotherapy. The aim of this study was to investigate the feasibility of using cytological evaluation to detect oral epithelial atypia amongst these patients. As a part of the continuous development in cancer therapy, this case control study was conducted in Khartoum, Sudan.

METHODS

Papanicolaou stained oral mucosal cells were obtained from 100 cancer patients receiving radiotherapy and/or chemotherapy (ascertained as cases), 50 cancer patients not exposed to either therapy (control 1), and 50 apparently healthy individuals (control 2).

STATISTICAL ANALYSIS

The data was analyzed by using a computer SPSS program, to obtain the Chi-square test.

RESULTS

Without prior knowledge of the subjects' group, oral epithelial atypia was detected in 7% of the cases. Inconclusive features of cytological atypia were observed in 13% of the cases. Atypia was not observed in both the control groups. Inflammatory infiltrate and viral cytopathic effects were identified in 32% and 8% of the cases respectively.

CONCLUSION

Cytological atypia, viral infections, and inflammatory infiltrates were detected after exposure to radiotherapy and/or chemotherapy.

Metal and Ceramic Bracket Effects on Human Buccal Mucosa Epithelial Cells

Objective: To test the null hypothesis that metal and ceramic brackets have no effect on the epithelial cells of the buccal mucosa.

Materials and Methods: Two metal and two ceramic brackets were bonded in 21 individuals of both sexes. With the use of liquid-based exfoliative cytology, morphometric and morphologic changes in buccal mucosa cells adjacent to these brackets were determined and were compared at three time points: baseline (T0), 60 days after placement (T1), and 30 days after removal of the brackets (T2).

Results: A decrease in nuclear area and an increase in cytoplasmic area occurred in the buccal mucosa cells adjacent to the brackets at T1 (P &lt; .01). At T2, this altered morphometry persisted only in cells adjacent to the metal brackets, although to a lesser degree than at T1 (P &lt; .01). A greater decrease in nuclear area was noted in cells adjacent to the metal brackets than in those next to the ceramic brackets (P &lt; .01). At T0, the proportions of surface and subsurface cells were similar, but at T1, a predominance of surface cells was observed (P &lt; .05). At all time points, smears of cells appeared normal or normal with some inflammatory changes.

Conclusion: The hypothesis is rejected. Placement of metal and ceramic brackets in the buccal cavity induces cellular alterations. These alterations do not suggest malignancy.

Genotoxicity of occupational exposure to wood dust: Micronucleus frequency and nuclear changes in exfoliated buccal mucosa cells

Occupational exposure to wood dust is associated with the occurrence of nasal cancer. In this study, we investigated micronuclei and nuclear changes (NCs: binucleates, karyorrhexis, karyolysis, and the "broken egg" effect) in exfoliated buccal cells of 20 workers exposed to wood dust and 20 age- and sex-matched controls. Micronucleus frequency and the frequency of each of the NCs were significantly higher for wood workers than controls (P < 0.01). Cigarette smoking was associated with increased frequencies of micronuclei and NCs in the buccal mucosa epithelium cells of both the control and exposed groups. Our findings indicate that buccal cells of wood workers display increased levels of genotoxicity and toxicity, and that these biomarker responses may be related to the increased cancer risk among wood workers.

Cytologic and DNA-cytometric examination of oral lesions in lichen planus

BACKGROUND

The aim of the present study was to evaluate the diagnostic value of exfoliative cytology (EC) and DNA image cytometry applied to oral lesions of lichen planus (LP; n = 56), in order to detect or exclude malignant transformation.

METHODS

Brush and excisional biopsies were obtained from 56 patients. In cases of oral LP in which brush biopsies were suspicious for tumor cells, nuclear DNA contents were measured, using a TV Image Analysis System.

RESULTS

In 50 patients EC yielded tumor cell-negative, doubtful in four cases and suspicious results obtained in two cases. DNA image cytometry revealed DNA-aneuploidy only in the two suspicious cases. The comparison between cytologic/DNA-cytometric diagnosis and biopsy histology resulted in a total agreement (LP without dysplasia: 54 and squamous cell carcinoma in LP: two cases).

CONCLUSIONS

In conclusion, cytology with DNA-cytometry is a highly sensitive, specific, and non-invasive method, which can be used for periodical follow up of oral LP lesions in order to early detect or exclude malignancy.

Evaluation of nuclear morphometry and DNA ploidy status for detection of malignant and premalignant oral lesions: quantitative cytologic assessment and review of methods for cytomorphometric measurements

PURPOSE

Detection of a precancerous or cancerous lesion when small is one of the most important factors to improve 5-year survival rates of oral cancer. Although surgical biopsy is the most definitive method for diagnosing oral lesions, it is impractical to routinely subject large numbers of patients to biopsy. Recently, cytomorphometric assessments improved by advanced computer-assisted image analysis systems have gained importance. This study was established to evaluate the efficacy of nuclear cytomorphometric analysis and DNA ploidy status for the detection of oral malignancies. Methods used for cytomorphometric analysis were also reviewed.

PATIENTS AND METHODS

Oral mucosal smears (n = 44) were obtained from patients (n = 22) presenting with various oral lesions using a cytobrush immediately before biopsy. Cytomorphometric measurements and nuclear Feulgen DNA content analysis were carried out after the Feulgen staining procedure. Smears from the lesion site constituted the study group whereas contralateral healthy mucosal sites served as control.

RESULTS

DNA ploidy analysis revealed 20 diploid (90.9%) and 2 aneuploid DNA patterns (9.1%) sampled from the lateral margin of the tongue and floor of the mouth. When only malignant lesions were considered, aneuploidy rate was 16.7% whereas a diploid pattern was indicated for 83.3% of the sample. With cytomorphometric measurements, a statistically significant difference was shown for nuclear perimeter, area, diameter equivalent to circle, minimum and maximum Feret, intensity, DNA content (c) and DNA index values.

CONCLUSIONS

Cytomorphometric analysis via oral brush biopsy is a valuable adjunct to biopsy for identification of premalignant and early stage cancerous oral lesions as a rapid and minimally invasive procedure with high specificity and sensitivity rates, requiring no topical or local anesthetic.

Application of cytology and molecular biology in diagnosing premalignant or malignant oral lesions

Early detection of a premalignant or cancerous oral lesion promises to improve the survival and the morbidity of patients suffering from these conditions. Cytological study of oral cells is a non-aggressive technique that is well accepted by the patient, and is therefore an attractive option for the early diagnosis of oral cancer, including epithelial atypia and squamous cell carcinoma. However its usage has been limited so far due to poor sensitivity and specificity in diagnosing oral malignancies. Lately it has re-emerged due to improved methods and it's application in oral precancer and cancer as a diagnostic and predictive method as well as for monitoring patients. Newer diagnostic techniques such as "brush biopsy" and molecular studies have been developed. Recent advances in cytological techniques and novel aspects of applications of scraped or exfoliative cytology for detecting these lesions and predicting their progression or recurrence are reviewed here.

Prediction of upper aerodigestive tract cancer by slide-based cytometry

AIM

To evaluate slide-based cytometry in screening for and following up of carcinoma of the upper aerodigestive tract using swabs for a minimal-invasive approach.

METHODS

Laser scanning cytometry (LSC) was used for multiparametric analysis of cells stained for cytokeratin and DNA to determine the DNA-index (DI) of the tumor cells. Histograms with 0.95 < DI < 1.05 and 1.9 < DI < 2.1 were defined as DNA euploid and any other DI as DNA aneuploid. After subsequent HE-staining, single cells were relocalized in order to document morphology. Conventional cytology was also performed on a subset of the slides. Routine histopathology of parallel biopsies served as gold standard in all cases.

RESULTS

115 swabs from 109 patients were obtained from the entire upper aerodigestive tract. 16 swabs were classified as insufficient for LSC. In the remaining 99 specimens, 1 benign lesion was misclassified as malignant, while 61 of the 75 malignant lesions were correctly identified. This corresponds to predictive values of 98.4% and 62.2% for the detection of malignant and benign samples by LSC.

CONCLUSION

This pilot study demonstrates the validity of LSC screening for the identification of tumor malignancy in the upper aerodigestive tract from swab collected cytological material.

Computerized morphometric discrimination between normal and tumoral cells in oral smears

The oral exfoliative cytology allows a quick and fairly accurate assessment of suspicious lesions of the oral cavity. Within this context, our paper proposes a quantitative approach, focusing on the construction of a classifier for detecting the presence of the tumoral cells on oral smears. The design of the classifier relies on a detailed computerized analysis of the individual morphometric features exhibited by two large known populations of normal and tumoral cells, respectively; the digital image processing was performed in the Zeiss KS400 environment. The classifier was implemented as a neural network with step activation function, whose parameters were obtained from an adequate training, based on the nuclear and cytoplasmic areas of the cells belonging to the two populations. Our procedure based on this classifier was meant to operate by identifying the tumoral or normal nature of any cell randomly selected from a smear. To identify the nature of an arbitrary cell, its nuclear and cytoplasmic areas are presented at the input of the classifier. The classification procedure was tested on several smears, and the results coincided with the pathological diagnosis in all the considered cases. The performances of our approach are discussed in comparison with other analytical methods previously reported in oral exfoliative cytology. These discussions emphasize the role of numerical information exploited for the classifier design, concluding that the individual morphometric features are more meaningful than the global characterization of smears by mean values.

Alcohol and oral cancer

Alcohol, particularly when associated with tobacco use, has been recognized as an important risk factor for mouth cancer for almost 50 years. Together, they are associated with approximately 75% of upper aerodigestive tract cancers. However, intake of alcohol remains high in many countries. The rising incidence of oral cancer has prompted a revaluation of the role of alcohol (both alone and in partnership with other etiologic agents). In this article, the potential role of alcohol in the development of oral cancer is reviewed. In particular, the effect of alcohol on cellular structure and function is considered by reference to histologic and exfoliative cytologic studies of the oral epithelia. Alcohol may influence the proliferative cells by both intracellular (e.g., endocytosis) and intercellular (permeability) pathways. The carcinogenic exposure of the proliferating stem cells in the basal layer may be regulated through these pathways. Individual variation might help explain why oral cancer arises in some, but not in most, people who smoke and consume excess alcohol. Despite this finding, alcohol is strongly associated with the development of oral cancer and other upper aerodigestive tract cancers. Efforts to reduce this burden on the individual and society must be directed toward patient and professional education and research regarding (genetic) susceptibility.

Cytologic and DNA-cytometric follow-up of oral leukoplakia after CO2- and Er:YAG-laser assisted ablation: A pilot study

BACKGROUND AND OBJECTIVES

The aim of the present pilot study was to determine therapeutic responses to Er:YAG- and CO(2)-laser ablation in patients with oral leukoplakia as evaluated by means of exfoliative cytology (EC) and DNA-image-cytometry (DNA-I).

STUDY DESIGN/MATERIALS AND METHODS

Ten patients exhibiting a total of 16 lesions affecting a variety of intraoral sites were randomly treated with either (1) an Er:YAG laser (300 mJ/pulse, 10 Hz, defocused mode) (ERL), or (2) an CO(2) laser (4-6 W, 20-50 Hz, focused mode) (CO). Brush (B) and incisional (I) biopsies were obtained from the respective lesions immediately before treatment (B, I) as well as 24-96 weeks postoperatively (B). In cases, in which EC revealed suspicious cells, nuclear DNA-contents were measured using a TV image analysis system.

RESULTS

Both treatment approaches resulted in a complete (C) or partial (P) remission of all investigated lesions. In particular, ERL exhibited C(3), P(5), and CO C(5), P(3). However, in the CO group, two of eight lesions showed a recurrence 32-48 weeks following treatment. Among all investigated lesions, both histological and EC/DNA-I diagnosis revealed no sign of malignancy or dysplasia before or following laser assisted ablation.

CONCLUSIONS

Within the limits of the present study, it may be concluded that both treatment approaches seem to have limitations to achieve predictable eradication of oral leukoplakia.

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.

Fresh and cultured buccal cells as a source of mRNA and protein for molecular analysis

We developed a method for obtaining viable buccal cells from mouthwash samples for use as a source of mRNA and protein. Immunofluorescent analysis showed that most cells were derived from nonkeratinized parabasal epithelia, with a minor proportion of proliferative cells. Gene expression was detected in buccal cells using reverse transcription PCR, Western blot analysis, and immunofluorescence. Using a keratinocyte-specific medium, buccal cells could be cultured on Matrigel™-coated permeable filters for up to 2 weeks while maintaining the expression of some epithelial-specific markers, including cytokeratin 13, cytokeratin 10, transferrin receptor, and β-integrin. The basal marker cytokeratin 14 and Ki67, an indicator of cellular proliferation, were detected in a few cells. We show that buccal cells can be obtained from a noninvasive procedure for use as a source of material for biochemical analyses. A population of the buccal cells can be maintained in culture for up to 2 weeks using keratinocyte-specific medium in combination with extracellular matrix.

Avaliação do exame citopatológico como método para diagnosticar a paracoccidioidomicose crônica oral

Com o objetivo de avaliar o exame citológico esfoliativo no diagnóstico das lesões orais da paracoccidioidomicose, foram estudados oito portadores desta doença. Em todos os casos, demonstrou-se o fungo através de esfregaços citológicos corados com impregnação pela prata Gomori-Grocott. Conclui-se que a citologia esfoliativa oral é um método diagnóstico útil e válido na paracoccidioidomicose, podendo auxiliar no controle terapêutico das formas orais desta micose.

Distribution of MUC1 in the normal human oral cavity is localized to the ducts of minor salivary glands

The change in expression of MUC1 from health to disease forms the basis of its use as a potential disease marker. Previous attempts at isolating MUC1 from normal, healthy human oral mucosa have, however, drawn conflicting conclusions as to its presence. Furthermore, when MUC1 was detected in the oral glycocalyx, it was not clear which cells were synthesising it. We examined human oral glycocalyx using pooled buccal smears from 50 normal individuals. Following isopycnic density centrifugation and membrane extraction with octyl glucoside and saponin, MUC1 was detected with the polyclonal antibody CT1. Immunohistochemistry using antibodies CT1 and BC2 was performed on sections from eight labial, seven palatal, four buccal, three retromolar pad, three dorsum of tongue and two ventral surface of tongue biopsies. In-situ hybridisation using MUC1 and cytoplasmic tail oligoprobes on sections from four palatal, seven labial and two retromolar pad biopsies was also carried out. MUC1 mRNA could only be detected in the minor salivary mucous glands. MUC1 has already been identified in the ducts of normal parotid and submandibular gland, and our findings demonstrate a similar distribution in minor salivary glands. We conclude that when present in the normal oral glycocalyx, the only oral source of MUC1 is from cell membranes of the minor salivary glands.

Effect of alcohol on the oral mucosa assessed by quantitative cytomorphometry

The effect of alcohol on the oral mucosa was assessed using quantitative cytomorphology applied to smears taken from clinically normal oral mucosa of patients attending an alcohol problem unit and results were compared to a control group (consisting of social and non-drinkers) attending a hospital for routine dental care. Smears were stained using the Papanicolaou method and the nuclear and cell boundaries of 50 randomly selected cells traced and mean areas (NA and CA, respectively) calculated. The average number of units of alcohol consumed were recorded for each group together with relevant blood tests. The alcohol group was further subdivided into "binge" and "regular" drinkers. No significant differences were found between mean NA and mean CA values for these two types of alcohol drinkers, despite a marked difference in weekly units consumed. However, a statistically significant reduction in mean cytoplasmic area (P < 0.001) and mean nuclear area (P < 0.01) was found for the alcohol group when compared to controls. In conclusion, excess alcohol intake may influence results for quantitative oral cytomorphology. Further research is indicated on the relative effects of alcohol (both topical and systemic).

Fluid phase endocytosis within buccal mucosal cells of alcohol misusers

The structure of the oral mucosa is now well characterised, although studies on oral epithelial cell function have received less attention. The aims of this study were to see whether endocytosis could be demonstrated in cells from oral smears and if so, to assess the effect of chronic high alcohol intake on such uptake. Buccal mucosal smears were collected from 135 patients (91 non- or social drinkers, and 44 patients with harmful alcohol use). Name, age, sex, and alcohol history (for alcohol problem patients) were recorded. Cell suspensions were incubated in a solution of bovine serum albumin (BSA)-coated fluorescently labelled latex microspheres (0.02 micron diameter) in Ham's F-10 culture medium for 1 h at 37 degrees C as a marker of fluid phase endocytosis. Uptake of microspheres was confirmed by confocal microscopy, and mean endocytosed fluorescence levels determined by flow cytometry. A repeat smear from 11 of the alcohol patients was taken 9-14 days later. Endocytosis was significantly reduced in both male (P < 0.01) and female (P < 0.01) alcohol problem patients compared to controls. Units of alcohol consumed and cigarettes smoked per day did not show a dose-response correlation with endocytosis in the alcohol problem patients. Apparent abstinence from alcohol had no further effect on endocytic uptake at days 9-14. This study shows that normal oral squamous cells removed as buccal smears readily endocytose fluorescent microspheres and that this capacity can be affected by alcohol. Chronic high alcohol intake would appear to down regulate endocytosis in buccal cells even up to 14 days of abstinence. This may have implications for the pathogenesis of oral mucosal disorders in long-term users.