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

Cytomorphometric analysis of oral submucous fibrosis and leukoplakia using methyl green-pyronin Y, Feulgen staining and exfoliative brush cytology

The incidence of potentially malignant oral pathology such as leukoplakia, oral submucous fibrosis and squamous cell carcinoma has increased in India. We investigated whether cytoplasmic diameter, nuclear diameter and nucleus:cytoplasm ratio in exfoliative cytology are reliable indicators of potentially malignant lesions. We also investigated methyl green-pyronin Y and Feulgen staining as simple time saving and cost effective staining techniques for diagnostic exfoliative cytology. Cell and nuclear diameters of squamous cells of normal buccal mucosa, oral leukoplakia and oral submucous fibrosis were measured using an ocular micrometer disc. The nucleus:cytoplasm ratios in pathological cells were compared to age, sex and site matched controls. We found a significant reduction in the mean cytoplasmic and nuclear diameter in the experimental groups compared to normal controls. Methyl green-pyronin Y stained smears were clearer than Feulgen stained cells. We suggest that a decreased mean cytoplasmic diameter of exfoliated buccal mucosal cells could serve as an early indicator of dysplastic change in lesions that otherwise appear benign. Methyl green-pyronin Y may be useful for identifying premalignant and malignant transformations before a lesion is visible. The simplicity of the technique makes its routine use feasible.

Quantitative proteomic analysis of oral brush biopsies identifies secretory leukocyte protease inhibitor as a promising, mechanism-based oral cancer biomarker

A decrease in the almost fifty percent mortality rate from oral cancer is needed urgently. Improvements in early diagnosis and more effective preventive treatments could affect such a decrease. Towards this end, we undertook for the first time an in-depth mass spectrometry-based quantitative shotgun proteomics study of non-invasively collected oral brush biopsies. Proteins isolated from brush biopsies from healthy normal tissue, oral premalignant lesion tissue (OPMLs), oral squamous cell carcinoma (OSCC) and matched control tissue were compared. In replicated proteomic datasets, the secretory leukocyte protease inhibitor (SLPI) protein stood out based on its decrease in abundance in both OPML and OSCC lesion tissues compared to healthy normal tissue. Western blotting in additional brushed biopsy samples confirmed a trend of gradual decreasing SLPI abundance between healthy normal and OPML tissue, with a larger decrease in OSCC lesion tissue. A similar SLPI decrease was observed in-vitro comparing model OPML and OSCC cell lines. In addition, exfoliated oral cells in patients’ whole saliva showed a loss of SLPI correlated with oral cancer progression. These results, combined with proteomics data indicating a decrease in SLPI in matched healthy control tissue from OSCC patients compared to tissue from healthy normal tissue, suggested a systemic decrease of SLPI in oral cells correlated with oral cancer development. Finally, in-vitro experiments showed that treatment with SLPI significantly decreased NF-kB activity in an OPML cell line. The findings indicate anti-inflammatory activity in OPML, supporting a mechanistic role of SLPI in OSCC progression and suggesting its potential for preventative treatment of at-risk oral lesions. Collectively, our results show for the first time the potential for SLPI as a mechanism-based, non-invasive biomarker of oral cancer progression with potential in preventive treatment.

Evaluation of single-cell biomechanics as potential marker for oral squamous cell carcinomas: a pilot study

OBJECTIVES

Early detection of oral cancer is a major health issue. The objective of this pilot study was to analyze the deformability of healthy and cancer cells using a microfluidic optical stretcher (OS).

MATERIAL AND METHODS

Different cancer cell lines, primary oral cancer cells, and their healthy counterparts were cultivated and characterized, respectively. A measurable deformation of the cells along the optical axis was detected, caused by surface stress, which is optically induced by the laser power.

RESULTS

All cells revealed a viscoelastic extension behavior and showed a characteristic deformation response under laser light exposure. The CAL-27/-33 cells exhibited the highest relative deformation. All other cells achieved similar values, but on a lower level. The cytoskeleton reacts sensitively of changing environmental conditions, which may be influenced by growth behavior of the cancer specimens. Nevertheless, the statistical analysis showed significant differences between healthy and cancer cells.

CONCLUSION

Generally, malignant and benign cells showed significantly different mechanical behavior. Cancer-related changes influence the composition of the cytoskeleton and thus affect the deformability, but this effect may be superimposed by cell cultivation conditions or cell doubling time. These influences had to be substituted by brush biopsies to minimize confounders in pursuing investigations.

Cytological artifacts masquerading interpretation

Background:

Cytological artifacts are important to learn because an error in routine laboratory practice can bring out an erroneous result.

Aims:

The aim of this study was to analyze the effects of delayed fixation and morphological discrepancies created by deliberate addition of extraneous factors on the interpretation and/or diagnosis of an oral cytosmear.

Materials and Methods:

A prospective study was carried out using papanicolaou and hematoxylin and eosin-stained oral smears, 6 each from 66 volunteer dental students with deliberate variation in fixation delay timings, with and without changes in temperature, undue pressure while smear making and intentional addition of contaminants. The fixation delay at room temperature was carried out at an interval of every 30 minutes, 1 day and 1 week and was continued till the end of 1 day, 1 week, and 1 month, respectively. The temperature variations included 60 to 70°C and 3 to 4°C.

Results:

Light microscopically, the effect of delayed fixation at room temperature appeared first on cytoplasm followed by nucleus within the first 2 hours and on the 4^th day, respectively, till complete cytoplasmic degeneration on the 23^rd day. However, delayed fixation at variable temperature brought faster degenerative changes at higher temperature than lower temperature. Effect of extraneous factors revealed some interesting facts.

Conclusions:

In order to justify a cytosmear interpretation, a cytologist must be well acquainted with delayed fixation-induced cellular changes and microscopic appearances of common contaminants so as to implicate better prognosis and therapy.

Cytomorphometric analysis of exfoliated cells in oral lichen planus

BACKGROUND

Tumors are distinguished from normal tissues partly by their pronounced variability of cellular and nuclear dimensions. Therefore, such factors may be an indicator to assess whether the cells are malignant or not. Exfoliative cytology is a reliable tool in assessing such changes in the uterine cervix and has been used in the oral cavity also with success. The aims and objectives of the following study were to evaluate the malignant changes by assessing the quantitative parameters such as cytoplasmic diameter, cytoplasmic perimeter and cytoplasmic area (CD, CP, CA) and nuclear diameter, nuclear perimeter and nuclear area (ND, NP, NA) and cytoplasmic to nuclear ratio in the exfoliated cells of various subtypes of oral lichen planus (OLP) using cytomorphometry.

MATERIALS AND METHODS

Oral exfoliated cells from nineteen cases of histologically proven OLP (1 atrophic, 13 reticular, 4 erosive and 1 plaque) and ten controls with healthy mucosa were taken and stained by Feulgen-Rossenback reaction and cytomorphometric analysis was performed using an image analysis software. The parameters taken into account were CD, CP, CA and ND, NP, NA. Furthermore CA/NA was calculated. The parameters were statistically analyzed using the t-test.

RESULTS

Cytomorphometric analysis of all the parameters showed no significant difference between the control group and the reticular/plaque subtypes, whereas statistically significant (P < 0.05) differences was obtained between the control group and the atrophic/erosive subtypes group when compared using t-test.

CONCLUSIONS

The cytomorphometric analysis of OLP shows that erosive/atrophic subtypes of OLP are at more risk and exfoliative cytology and cytomorphometry can be used as a tool to assess the malignant changes.

Emerging roles of MCPH1: expedition from primary microcephaly to cancer

Genetic mutations in microcephalin1 (MCPH1) cause primary autosomal recessive microcephaly which is characterized by a marked reduction in brain size. MCPH1 encodes a centrosomal protein with three BRCT (BRCA1 C-terminal) domains. Also, it is a key regulator of DNA repair pathway and cell cycle checkpoints. Interestingly, in the past few years, many research studies have explored the role of MCPH1, a neurodevelopmental gene in several cancers and its tumor suppressor functions have been elucidated. Given the diverse new emerging roles, it becomes critical to review and summarize the multiple roles of MCPH1 that is currently lacking in the literature. In this review after systematic analysis of literature, we summarise the multiple functional roles of MCPH1 in centrosomal, DNA repair and apoptotic pathways. Additionally, we discuss the considerable efforts taken to understand the implications of MCPH1 in diseases such as primary microcephaly and its other emerging association with cancer and otitis media. The promising view is that MCPH1 has distinct roles and its clinical associations in various diseases makes it an attractive therapeutic target.

The role of tobacco as an etiological agent for oral cancer: Cytomorphometrical analysis of the buccal mucosa in tobacco users

BACKGROUND

Histopathological diagnosis of lesions arising from the intake of tobacco is based on subjective evaluation of morphological alterations within the lesional tissue. Oral exfoliative cytology is a non-invasive diagnostic technique for early detection of oral premalignant and malignant lesions. Morphometric techniques have been advocated as objective and reproducible methods of detecting changes before they are visible by routine microscopy and can facilitate differentiation of normal and abnormal epithelium. This study was conducted to assess the morphometric parameters (cell diameter, nuclear diameter and nuclear cytoplasmic ratio [N:C ratio]) in tobacco smokers and chewers and to evaluate the variations, if any.

MATERIALS AND METHODS

The study was conducted on cytological smears obtained from oral lesions of patients with habit of tobacco smoking (Group B) and tobacco chewing (Group C). Group A comprised of subjects free from oral lesions and not using tobacco in any form. Patients with both the habits were excluded. The smears were stained using Papanicoloaou staining method. For morphometric analysis, Microimage 3.0 image analysis software was employed. The statistical test employed was an analysis of variance and P < 0.05 was considered as significant.

RESULTS

The results of this study showed that the cellular diameter was progressively reduced and nuclear diameter progressively increased from Group A to Group B to Group C. The N:C ratio also showed a progressive increase from Group A to Group C.

CONCLUSION

The results confirmed that tobacco chewing and smoking influenced the cytomorphology of normal appearing buccal mucosa and the degree of these changes were found to be greater in chewers as compared to smokers.

Evaluation of oral mucosal epithelium in diabetic male patients by exfoliative cytology method

Background

The goal of present study is to examine comparatively the epithelium of oral mucosa in persons with diabetes types I and II and the healthy persons by cytomorphometric method.

Methods

Cytology smear was prepared from oral mucosa epithelium in 24 persons with diabetes and 30 healthy persons were stained by papanicolao method. Its before, from patients were requested acquiring written. The quantitative cytomorphometric characteristics were measured in each group by motic plus 2 software. Also, the qualitative evaluation of cytology slides are performed in three groups.

Results

There were decrease in the nuclear and cytoplasmic size, (P < 0.001) and increase in the ratio of nuclear to cytoplasm size in buccal mucosal areas (P = 0.001) and tongue (P = 0.011) of diabetic persons compared to the healthy persons. There was no significantly statistical difference in diabetic persons types I and II in buccal mucosal area (P = 0.15) and tongue (P = 0.86) in quantitative characteristics of cytomoerphometry. In nuclear and cytoplasm size, there was a significant statistical difference in persons with diabetes type I and persons of control I and persons with diabetes type II and persons of control II in buccal mucosa and the tongue (P < 0.001). Bilobed or multi-lobed nuleous, karyorrhexis and vacuolization of cytoplasm were more in diabetic persons compared to the healthy ones (P < 0.001).

Conclusion

Diabetes are effective in creating some quantitative and qualitative cytometric alterations in the oral mucosa but the type of diabetes doesn’t seem to be effective on these changes.

The use of quantitative cytology in identifying high-risk oral lesions in community practice

OBJECTIVE

This study evaluated whether quantitative cytology (QC) can disclose abnormal DNA content (aneuploidy) and abnormal nuclear morphology of high-risk potentially malignant disorders (PMDs) of the oral mucosa found in the community in reference to clinicohistopathologic features.

STUDY DESIGN

A total of 171 patients at community-based clinic with suspicious oral lesions were evaluated with concurrent but independent histopathologic and QC assessments.

RESULTS

QC-positive results were associated with oral lesions with higher clinical risk factors: large size, nonhomogeneous surface texture, and located at high-risk anatomic sites. Only 3% of benign/reactive and 5% of low-risk PMDs were QC positive, while 92% of high-risk PMDs and 88% of squamous cell carcinomas (SCCs) were QC positive. The sensitivity and specificity of QC for detection of high-grade dysplasia/SCC were 89% and 97%.

CONCLUSIONS

QC could serve as an adjunctive tool for the detection of high-risk PMD/SCC requiring immediate clinical care.

A study on cytomorphometric analysis of exfoliative buccal cells in iron deficiency anemic patients

Aim:

The aim was to evaluate the quantitative changes in nuclear diameter (ND), cytoplasmic diameter (CD) and nuclear/cytoplasmic ratio (N/C) in cytological buccal smears of iron deficiency anemic patients by comparing with normal healthy individuals.

Materials and Methods:

The study group consisted of 40 healthy individuals and 40 iron deficiency anemic patients who were selected on clinical history, hematological investigations, and confirmed by serum ferritin levels. Exfoliative buccal smears stained with PAP stain were evaluated for cytoplasimic, nuclear diameters, and nuclear/cytoplasmic ratios (N/C) using Image Proexpress Version 6.0 image analysis system. All the parameters were statistically analyzed by using unpaired ‘t’ test.

Results:

A significant increase is seen in the average nuclear diameter (ND) and N/C ratio of the anemic group when compared to the control group. The average cytoplasmic diameter (CD) did not show any statistical difference among the two groups.

Conclusion:

Oral exfoliative cytological techniques could possibly be a noninvasive alternative diagnostic tool for iron deficiency anemia.

Trends in oral cancer rates in Isfahan, Iran during 1991-2010

BACKGROUND

There is a variation in trends of oral cancers all over the world. Many investigations have reported evidence of an increasing incidence in oral cancers during recent years. The purpose of this study was to investigate time trend and changes in demographic distribution of oral cancers incidence in Isfahan during 1991-2010.

MATERIALS AND METHODS

In this retrospective analytic study archive of Oral Pathology Department of School of Dentistry, Isfahan University of Medical Sciences from 1991 to 2010 were reviewed. A total of 231 Pathology reports were analyzed. Age, sex, primary site, histologic type of cancer, and the referral year were recorded. Data were analyzed by using Jointpoint Regression Program 3 and SPSS 18. P value less than 0.05 consider as significant level.

RESULTS

Out of all malignancies, 55% were male and 45% were female. The most frequent cancer was squamous cell carcinoma. Comparing the two time intervals (1991-2000) and (2001-2010) showed that the ratio of carcinomas and salivary gland tumors had decreased while there was an increase in incidence of sarcomas and lymphomas. Among young persons, the occurrence of oral carcinomas (mostly SCC) is rare but sarcomas were more common in younger patients. Gingiva was the most frequently involved in oral cancers with (46%), followed by tongue with (18%).

CONCLUSION

: According to this study it revealed that some changes in trends of oral cancer have happened in Isfahan that calls for more study and evaluation of etiologies of these changes.

The use of salivary cytokines as a screening tool for oral squamous cell carcinoma : A review of the literature

Oral squamous cell carcinoma (OSCC) is the most common type of head and neck cancer. The 5-year survival rate has remained below 50% over the last two decades, and new tools for early diagnosis are needed. Saliva has been used for diagnosis of several systemic diseases, and its use for diagnosis of OSCC has been sought extensively. Among the many salivary analytes for diagnosis of OSCC, accumulating evidences indicate the possibility of using salivary cytokines. Overproduction of proinflammatory, proangiogenic cytokines by OSCC cells has been reported, and their role in tumor progression and angiogenesis is well established. However, many inflammatory conditions and immunological diseases could affect the levels of cytokines in serum and saliva. This article has reviewed publications in this matter, and some strengths and weaknesses have been pointed out. Conclusively, large-scale investigations are required for validation of the use of salivary cytokines for diagnosis of OSCC, with consideration to the influential role of periodontal inflammation in their levels.

"Catch Them before it Becomes Too Late"-Oral Cancer Detection. Report of Two Cases and Review of Diagnostic AIDS in Cancer Detection

Most oral and oropharyngeal squamous cell carcinomas (OOSCCs) are in advanced stages at diagnosis, and treatment does not improve survival rates. Early recognition and diagnosis of OOSCCs might improve patient survival and reduce treatment-related morbidity. The purpose of this article is to create awareness among the general practitioners to recognize the premalignant and early malignant lesions and to review the different diagnostic aids for the detection of cancer.

Expression of p53 protein and ki-67 antigen in oral premalignant lesions and oral squamous cell carcinomas: An immunohistochemical study

Aim:

To study expression of p53 protein and ki-67 antigen in normal, non-dysplastic, dysplastic, premalignant and malignant lesions of the oral mucosa.

Materials and Methods:

The standard immunohistochemical method along with MIB-1 and DO-7; DAKO antibodies was used to study the expression of p53 and ki-67 in paraffin-embedded tissue specimens.

Results:

All samples studied showed positive staining for p53 and ki-67. Only one case each from leukoplakia and oral squamous cell carcinoma (OSCC) groups showed negative staining for ki-67. The staining was confined to basal layer in most of the cases except OSCC in which it was seen in all layers. The intensity of staining was moderate to intense. The percentage of p53-positive cells in normal mucosa was 15-25% which was increased to 95% in malignant mucosa. Statistical analysis revealed that the expression of p53 and ki-67 increases as normal oral mucosa becomes dysplastic and undergoes malignant transformation.

Conclusion:

These results emphasize the potential use of p53 protein and ki-67 antigen as markers of malignant transformation and carcinogenesis in oral premalignant lesions, conditions and OSCC, respectively; and in future they may serve as prognostic tools in the early detection of malignant transformation in oral premalignant lesions and conditions.

Cytopathology: a useful technique for diagnosing oral lesions?: a systematic literature review

Oropharyngeal cancer is the 11th most common cancer worldwide. The diagnostic method of choice for oral cavity lesions is biopsy and pathological examination. Cytopathology is a simple and inexpensive method, but it is not yet widespread among dental professionals. The aim of this study was to evaluate the evidence for the effectiveness of cytopathology in diagnosing oral lesions. We conducted a systematic literature review of randomized clinical trials that compared the diagnostic accuracies of oral lesion cytology and histopathology. We used the following search terms: cytology, oral lesions, and oral cancer. The meta-analysis was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Between 1967 and 2010, there were 80 relevant articles in the literature, 14 of which were included in this study. The I-square for sensitivity was 80.2%, and the specificity value was 96.7%. The pooled sensitivity was 0.942 [95% confidence interval (CI): 0.926-0.955], and the pooled specificity was 0.970 (95% CI: 0.963-0.975). The area under the curve was 0.9901. Our study suggests that cytology has good sensitivity and specificity for the diagnosis of oral lesions and allows the use of other associated techniques, such as DNA analysis, which may improve the accuracy of cytology.

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.

Applications of OralCDx® methodology in the diagnosis of oral leukoplakia

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

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

Action mechanism of inhibin α-subunit on the development of Sertoli cells and first wave of spermatogenesis in mice

Inhibin is an important marker of Sertoli cell (SC) activity in animals with impaired spermatogenesis. However, the precise relationship between inhibin and SC activity is unknown. To investigate this relationship, we partially silenced both the transcription and translation of the gene for the α-subunit of inhibin, Inha, using recombinant pshRNA vectors developed with RNAi-Ready pSIREN-RetroQ-ZsGreen Vector (Clontech Laboratories, Mountain View, Calif). We found that Inha silencing suppresses the cell-cycle regulators Cyclin D1 and Cyclin E and up-regulates the cell-cycle inhibitor P21 (as detected by Western blot analysis), thereby increasing the number of SCs in the G1 phase of the cell cycle and decreasing the amount in the S-phase of the cell cycle (as detected by flow cytometry). Inha silencing also suppressed Pdgfa, Igf1, and Kitl mRNA levels and up-regulated Tgfbrs, Inhba, Inhbb, Cyp11a1, Dhh, and Tjp1 mRNA levels (as indicated by real-time polymerase chain reaction [PCR] analysis). These findings indicate that Inha has the potential to influence the availability of the ligand inhibin and its antagonist activin in the SC in an autocrine manner and inhibit the progression of SC from G1 to S. It may also participate in the development of the blood–testis barrier, Leydig cells, and spermatogenesis through its effect on Dhh, Tjp1, Kitl, and Pdgfa. Real-time PCR and Western blot analyses of Inha, Inhba, and Inhbb mRNA and Inha levels over time show that Inha plays an important role in the formation of round spermatid during the first wave of spermatogenesis in mice.

Exciting new advances in oral cancer diagnosis: avenues to early detection

The prognosis for patients with oral squamous cell carcinoma remains poor in spite of advances in therapy of many other malignancies. Early diagnosis and treatment remains the key to improved patient survival. Because the scalpel biopsy for diagnosis is invasive and has potential morbidity, it is reserved for evaluating highly suspicious lesions and not for the majority of oral lesions which are clinically not suspicious. Furthermore, scalpel biopsy has significant interobserver and intraobserver variability in the histologic diagnosis of dysplasia. There is an urgent need to devise critical diagnostic tools for early detection of oral dysplasia and malignancy that are practical, noninvasive and can be easily performed in an out-patient set-up. Diagnostic tests for early detection include brush biopsy, toluidine blue staining, autofluorescence, salivary proteomics, DNA analysis, biomarkers and spectroscopy. This state of the art review critically examines these tests and assesses their value in identifying oral squamous cell carcinoma and its precursor lesions.

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.

Emergence of keratin 17 vs. loss of keratin 13: their reciprocal immunohistochemical profiles in oral carcinoma in situ

To evaluate differential expressions for keratin (K) subtypes 13 and 17 in oral borderline malignancies, we examined 67 surgical specimens of the oral mucosa for their immunohistochemical profiles. From those specimens, 173 foci of epithelial dysplasia, 152 foci of carcinoma in situ (CIS), and 82 foci of squamous cell carcinoma (SCC) were selected according to our diagnostic criteria, along with 20 areas of normal epithelia. In normal epithelia, there was no K17 positivity (0%), whereas definite K13 positivity (100%) was observed. The same tendencies were obtained in mild (undefined) and moderate (true) epithelial dysplasias (K17: 0%; K13: 100%). In contrast, all CIS (100%) had K17 positivities, while K13 positivities were lost in many of them (7%). Similar tendencies were confirmed in invasive SCC (K17: 100%, K13: 4%). Simultaneous immunopositivities for K17 and K13 were found only in SCC (7%) and CIS (4%) foci with distinct keratinization. These foci also showed K10 positivities, though K10 positive areas were not identical to K13 positive areas. The results indicate that expressions of K17 and K13 are reciprocal in oral epithelial lesions and that the K17 emergence is related to malignancies.

Comparison of the Cytobrush®, dermatological curette and oral CDx® brush test as methods for obtaining samples of RNA for molecular analysis of oral cytology

OBJECTIVE

Interest in oral exfoliative cytology has increased with the availability of molecular markers that may lead to the earlier diagnosis of oral squamous cell carcinoma. This research aims to compare the efficacy of three different instruments (Cytobrush, curette and Oral CDx brush) in providing adequate material for molecular analysis.

METHODS

One hundred and four cytological samples obtained from volunteer healthy subjects were analysed using all three instruments. The clinical and demographical variables under study were age, sex and smoking habits. The three instruments were compared for their ability to obtain adequate samples and for the amount of RNA obtained using quantitative real-time polymerase chain reaction (PCR-qRT) analysis of the Abelson (ABL) housekeeping gene.

RESULTS

RNA of the ABL gene has been quantified by number of copies. Adequate samples were more likely to be obtained with a curette (90.6%) or Oral CDx (80.0%) than a Cytobrush (48.6%); P < 0.001. Similarly, the RNA quantification was 17.64 ± 21.10 with a curette, 16.04 ± 15.81 with Oral CDx and 6.82 ± 6.71 with a Cytobrush. There were statistically significant differences between the Cytobrush and curette (P = 0.008) and between the Cytobrush and OralCDx (P = 0.034). There was no difference according to the demographical variables.

CONCLUSIONS

Oral exfoliative cytology is a simple, non-invasive technique that provides sufficient RNA to perform studies on gene expression. Although material was obtained with all three instruments, adequate samples were more likely to be obtained with the curette or Oral CDx than with a Cytobrush. The Oral CDx is a less aggressive instrument than the curette, so could be a useful tool in a clinical setting.

Early detection of premalignant lesions and oral cancer

Cancers of the oral cavity account for approximately 3% of malignancies diagnosed annually in the United States. As with other upper aerodigestive tract cancers, 5-year survival rates for oral cavity cancers decrease with delayed diagnosis. Cancers of the oral cavity are thought to progress from premalignant/precancerous lesions, beginning as hyperplastic tissue and developing into invasive squamous cell carcinoma. Despite the general accessibility of the oral cavity during physical examination, many malignancies are not diagnosed until late stages of disease. To prevent malignant transformation of these oral precursor lesions, multiple screening and detection techniques have been developed to address this problem.

Comparison of three sampling instruments, Cytobrush, Curette and OralCDx, for liquid-based cytology of the oral mucosa

Exfoliative cytology of the oral cavity is a simple and noninvasive technique that permits the study of epithelial cells. Liquid-based cytology is an auxiliary diagnostic tool for improving the specificity and sensitivity of conventional cytology. The objective of our study was to compare the quality of normal oral mucosa cytology samples obtained using three different instruments, Cytobrush®, dermatological curette and Oral CDx® for liquid-based cytology. One hundred four cytological samples of oral cavity were analyzed. Samples were obtained from healthy volunteer subjects using all three instruments. The clinical and demographic variables were age, sex and smoking habits. We analyzed cellularity, quality of the preparation and types of cells in the samples. All preparations showed appropriate preparation quality. In all smears analyzed, cells were distributed uniformly and showed no mucus, bleeding, inflammatory exudate or artifacts. We found no correlation between the average number of cells and the type of instrument. The samples generally consisted of two types of cells: superficial and intermediate. No differences were found among the cytological preparations of these three instruments. We did not observe basal cells in any of the samples analyzed.

Techniques for precancerous lesion diagnosis

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

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

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

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.

Diagnostic clinical aids in oral cancer

Conventional oral exploration (visual and palpation examination) constitutes the current gold standard for oral cancer screening, while biopsy and histopathological examination represents the indispensable study for the detection of cases in patients with an identified lesion. Imaging techniques (DPT, CT, and MRI) are frequently used to supplement the clinical evaluation and staging of the primary tumour and regional lymph nodes. There are also a number of techniques that may contribute to the diagnosis of oral cancer: toluidine blue test has been used as a diagnostic aid for the detection of oral cancer over decades. Recently developed light-based detection systems have progressively improved in sensitivity and specificity, but multicentre controlled studies conducted by general dental practitioners must be designed in order to justify their application. The oral brush biopsy appears to overestimate dysplastic lesions and produces a high number of false-positive results. In the near future, immunological and biochemical alterations in the serum (e.g., circulating immune complexes, carcinoembryonic antigen, squamous cell carcinoma associated antigen, inhibitor of apoptosis, cytokeratin fragments, and annexin A1) as well as specific saliva analysis (e.g., cancer related cytokines, metalloproteinases, epithelial tumour markers, DNA promoter hypermethylation, and saliva micro-RNA) may become important tools for the detection of oral cancer.

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.

Value of centrifugated liquid-based cytology by Papanicolaou and May-Grünwald in oral epithelial cells

For many years, liquid-based cytology (LBC) has been developed for cervical cancer screening and not oral cancer, as it requires automated devices. The aim of this study was to compare the utility of centrifugated CLBC preparation with that of direct preparation in oral lesions, by Papanicolaou (Pap) and May Grünwald-Giemsa's (MGG) methods. A total of 100 consecutive cases of oral lesions were investigated. We compared the results obtained by the CLBC performed by cytocentrifugation with those obtained by direct smear applying Pap and MGG methods. The comparison between CLBC and direct smears was based on the thickening or adequacy of the smear, distribution of cells and staining quality. All smears in CLBC and direct preparation were found adequate. For thickness of the smear, 40% and 42% were excellent, 33% and 30% were good, and 27% and 28% were acceptable by LBC and direct preparation, respectively. For the distribution of cells and scantiness of background elements, 92 (92%) smears of the CLBC have revealed clear, well distributed smears, compared to 70 (70%) of those in direct preparation. For the staining quality with the Pap method, 39% and 69% were excellent staining quality, 25% and 20% were good, and 36% and 11% were acceptable for CLBC and direct preparation, respectively. In MGG method, 9% and 22% were excellent staining quality, 23% and 36% were good and 68% and 43% were acceptable for CLBC and direct preparation respectively. CLBC performed by cytocentrifugation is inexpensive, and reduces inadequate smears and background staining.

Oral cytology revisited

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

Molecular biology: an early detector of oral cancers

Oral cancers have been one of the leading causes of deaths particularly in the developing countries. Prime reason for this high mortality and morbidity is attributed to the delay in diagnosis and prompt treatment. Relentless research in the field of oncology has led to advent of novel procedures for the early detection of oral cancers. Molecular biology is highly promising in this regard. It is a procedure that detects alterations at a molecular level much before they are seen under a microscope and much before clinical changes occur. Molecular studies serve as basis by which we will eventually be able not only to augment clinical assessment and classification of oral lesions but also predict malignant potential of oral lesions, thus reducing incidence and increasing the scope for early diagnosis and treatment of oral cancers. However, making such sophisticated tools available for the common man in developing countries is one of the most important challenges faced today.

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.

Advantages and difficulties of brush cytology in the identification of early oral cancer

Background: Early oral cancer is asymptomatic and highly curable, but unfortunately most cancers are advanced by the time when they are discovered, so the mortality is relatively high. The aim of this study was to refer the advantages as well as the difficulties of brush cytology in the identification of early oral cancer. Methods: Cytological smears obtained from of the oral mucosa of 36 patients were evaluated. The materials were taken with a cytobrush by scraping the surface of the suspected lesions, fixed with cytospray fixative and stained with the Papanicolaou method, whereas the residual was prepared by the liquid-based technique Thin-Prep 2000. Results: There were 29 inflammatory and mild dysplastic lesions, three cases with mild dysplasia only and two cases with severe dysplasia possible carcinoma. Another two showed squamous cell carcinoma. Histological examination of possible malignant and malignant cases showed well differentiated squamous cell carcinomas, so wide excisions were performed. Conclusion: Oral cytology is well accepted by the patient and attractive option for the early diagnosis of the oral cancer. It is useful when the lesion is large or multiple or the patients refuse biopsy. However there are factors that contribute to a false negative diagnosis such as the selection of the site of biopsy, necrosis, blood crusting, lack of adequate training, and the fact that malignant features of squamous cell carcinoma can be subtle resembling dysplasia.

The use of an oral brush biopsy without computer-assisted analysis in the evaluation of oral lesions: a study of 94 patients

OBJECTIVE

The objective of this study was to evaluate the sensitivity and specificity of modified brush biopsy without computer-assisted analysis in the detection of oral premalignant and malignant lesions.

STUDY DESIGN

Ninety-four patients attending outpatient clinics who exhibited oral lesions suspicious of premalignancy or malignancy were enrolled. All patients underwent an oral brush biopsy using a baby toothbrush followed by a scalpel biopsy. The specimens were analyzed manually in a double-blinded fashion. Sensitivity and specificity were used for the statistical analysis of the samples. Statistical significance was determined using the normal approximation to the binomial distribution of matched results, approximated by the Student t distribution mean test (paired t test).

RESULTS

Seventy-nine patients with adequate transepithelial brush biopsy samples were included in the study group. When compared to scalpel biopsy, the statistical sensitivity of the brush biopsy was greater than 76.8% (P < .05) while the statistical specificity was greater than 93.3% (P < .05). There were 4 false negative brush biopsy cases. The 4 false negative patients turned out to be dysplasia/ malignancy on histopathology. All 4 were patients with clinical oral submucous fibrosis.

CONCLUSION

The oral brush biopsy without computer-assisted analysis was found to be a painless, noninvasive test for evaluating oral lesions. The toothbrush brush biopsy with manual analysis had much [corrected] lower sensitivity and specificity than the commercially available oral brush biopsy with computer-assisted analysis. The results demonstrate that by using a toothbrush to obtain an oral brush biopsy sample, oral lesions can be easily evaluated in a resource challenged settings to rule out dysplasia and carcinoma.

[Performance of conventional oral brush biopsies]

BACKGROUND

This study evaluated the performance of oral brush biopsies using standard morphological analysis and haematoxylin and eosin (HE) staining for detecting oral squamous cell carcinomas and their respective precursor lesions

PATIENTS AND METHODS

Brush biopsies were obtained in 169 consecutive patients who underwent routine biopsies and histological examination for clinically suspicious oral lesions. Air-dried smears were processed by acetone fixation and HE staining. Cytological assessment used well-established criteria of atypia to classify the specimen as either "tumor negative" (no signs of atypia, no malignant cells) or "tumor positive" (malignant cells, any sign of atypia or doubtful cells).

RESULTS

Despite a sufficient number of cells, a definite cytological diagnosis could not be established in six cases. According to the criteria specified above, these specimens were classified as "tumor positive." The cytological analysis identified 49 out of 62 oral malignancies (sensitivity 79%). Seven out of 107 benign lesions were classified as false positive (specificity 93%). The positive and negative predictive values were each 88%.

CONCLUSION

Oral brush biopsies will identify only about 80% of oral malignancies when the smears are processed by routine HE stains and are analysed via standard morphological criteria. Thus, this technique should not be used for diagnostic proof or to exclude malignant cells in a lesion suspicious for cancer. However, oral brush biopsy provides a versatile back-up strategy to uncover the true nature of the disease if a lesion is clinically considered benign by mistake.