Comparison of spatula and cytobrush cytological techniques in early detection of oral malignant and premalignant lesions: a prospective and blinded study

The Diagnostic Potential of Non-Invasive Tools for Oral Cancer and Precancer: A Systematic Review

OBJECTIVES

This systematic review aimed to analyse the published evidence for the use of non-invasive methods for the early detection of oral squamous cell carcinoma (OSCC) and oral potentially malignant disorders (OPMDs).

METHODS

The literature was systematically searched through several databases: PubMed, Cochrane Library, and Web of Science. Additional exploration was performed through cross-checks on the bibliographies of selected reviews. The inclusion criteria involved studies assessing the application of non-invasive tests on humans in the screening, diagnosis, or surveillance of OSCC or OPMDs and reporting sensitivity (SE) and specificity (SP). The Newcastle-Ottawa scale (NOS) was applied to assess the quality of the studies included.

RESULTS

The search strategy resulted in 8012 preliminary records. After a duplicate check, 116 titles remained. After abstract analysis, 70 papers remained. After full text analysis, only 54 of the 70 papers fit the inclusion criteria (28 were original articles and 26 were reviews). Those 26 reviews were used to manually search for further original articles. From this last search, 33 original articles were found. Thus, a total of 61 original studies were included and investigated. Findings from this systematic review indicate useful information, such as a description of the mechanisms, ease of use, limitations, and SE and SP values, to drive the choice of the optimal minimally invasive method to be utilized as an adjunctive tool to examine the suspicious lesions.

CONCLUSIONS

Each of the analysed tools can be improved or implemented, considering their high SE and low SP. Despite advancements, incisional biopsy continues to be the gold standard for the definitive diagnosis of oral cancer and precancerous lesions. Further research and development are essential to improving the sensitivity, specificity, and reliability of non-invasive tools for widespread clinical application.

Effectiveness of adjunctive screening tools for potentially malignant oral disorders and oral cancer: A systematic review

Background and objectives

To enhance the abilities of healthcare professionals to make informed treatment decisions and establish accurate diagnoses, it is essential to assess the diagnostic reliability of different adjunctive aids. This systematic review aimed to compare the accuracy of various adjunctive methods for diagnosing suspected oral cancer (OC) or potentially malignant oral disorders (OPMD) in adults against histopathological investigative results.

Materials and methods

The review protocol registered in the PROSPERO database (CRD42023463525) was developed in strict accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis-Diagnostic Test Accuracy checklist. A comprehensive electronic search was conducted to identify relevant research articles published between January 2014 and April 2023 using the PubMed and EBSCO databases. The research question was meticulously structured following the participants' index test, reference standard, target condition, and study setting framework. To evaluate methodological quality and assess the risk of bias (RoB), the Quality Assessment for Diagnostic Accuracy Studies-2 tool was used.

Results

An initial search yielded 483 publications, which were reduced to 278 after removal of duplicates. Finally, 85 publications underwent full-text review by two investigators, which lead to 29 studies that met the inclusion criteria. Among these, 7% had a low RoB, 72% had an unclear RoB, and 21% had a high RoB. Applicability concerns were expressed in 59% of the studies with low concern, 31% with unclear quality evidence of concern, and 10% with high concern.

Conclusion

The review findings support the use of these diagnostic methods as valuable adjuncts to biopsy for the early detection of various OPMD and OC. They also highlight the importance of regular screening and awareness in reducing the global burden of OC, while acknowledging that they cannot replace the gold standards of surgical biopsy and histopathological evaluation.

Micronuclei detection in oral cytologic smear: does it add diagnostic value?

BACKGROUND

Screening and early diagnosis of oral squamous cell carcinoma (OSCC) are directly associated with increased survival rate and improved prognosis. Noninvasive diagnostic tools have been implemented in the early detection as toluidine blue staining, optical imaging, and oral cytology. This study aimed to assess and compare the presence of micronuclei (MN) in oral exfoliative cytology of healthy controls, subjects exposed to high-risk factors for oral cancer, subjects with oral potentially malignant lesions (OPMLs), and those with malignant oral lesions.

SUBJECTS AND METHODS

A total number of 92 subjects were divided into 46 healthy controls with no oral mucosal lesions (23 with no evidence of cancer risk factors and 23 with cancer risk factors), 23 with OPMLs and 23 with oral malignant lesions. All the 92 participants were subjected to cytological sampling for detection of MN. The final diagnosis of the oral lesions was confirmed by the histopathological picture and compared to the cytological results.

RESULTS

The results showed that the diagnostic accuracy of MN was higher in OPMLs group (95.2%). The sensitivity of MN test in malignant group was much lower (52.2%); however, all the cytological criteria of malignancy were markedly detected as compared to the OPMLs group.

CONCLUSIONS

Conventional oral cytology supported by MN is highly beneficial as adjunctive tool in the screening for early detection of dysplastic oral lesions.

Retrospective evaluation of the oral brush biopsy in daily dental routine - an effective way of early cancer detection

OBJECTIVES

Oral brush biopsies are a well researched index for early detection of oral cancer in specialised centers. But the performance of the exfoliative biopsy is not yet researched in daily dental routine.

METHODS

Private dentists and private oral surgeons in Germany took brush biopsies out of 814 suspicious lesions from 670 patients using the Orcellex brush while regular dental appointments. The analyses of the biopsies were performed by the Cytological Laboratory of Bonn (CLB) using liquid-based cytology.

RESULTS

The final results were 74 oral squamous cell carcinomas and one verrucous carcinoma, histological proven, 232 cases of leukoplakia, 242 cases of lichen planus, 17 cases of erythroplakia, 259 cases of benign inflammatory, traumatic or hyperplastic oral lesions. The sensitivity for the detection of cancer cells using brush biopsy archived 100%, the specificity for the detection of non-neoplastic cells was 86.5%. The positive predictive value was 43.1%, the negative predicative value was at 100%.

CONCLUSION

The oral brush biopsy seems to be a sufficient tool for early cancer detection in private dental offices.

CLINICAL RELEVANCE

Generally, practicing dentists do not see various oral squamous cell carcinomas in their careers, so the experience in identifying oral squamous cell carcinomas as such is very low. The brush biopsy might help them in cases of doubt to prevent tumors from expansive growth.

A Systematic Review of Oral Biopsies, Sample Types, and Detection Techniques Applied in Relation to Oral Cancer Detection

Background: Early identification of the stage of oral cancer development can lead to better treatment outcomes and avoid malignant transformation. Therefore, this review aims to provide a comprehensive overview that describes the development of standardized procedures for oral sample collection, characterization, and molecular risk assessment. This can help investigators to choose the appropriate sampling method and downstream analyses for different purposes. Methods: This systematic review was conducted according to the PRISMA guidelines. Using both PubMed and Web of Science databases, four independent authors conducted a literature search between 15 and 21 June 2021. We used key search terms to broaden the search for studies. Non-conforming articles were removed using an EndNote-based and manual approach. Reviewers used a designed form to extract data. Results: This review included a total of 3574 records, after eliminating duplicate articles and excluding papers that did not meet the inclusion criteria. Finally, 202 articles were included in this review. We summarized the sampling methods, biopsy samples, and downstream analysis. The biopsy techniques were classified into tissue and liquid biopsy. The common sequential analysis of tissue biopsy includes histopathological examination such as H&E or IHC to identify various pathogenic features. Meanwhile, liquid samples such as saliva, blood, and urine are analyzed for the purpose of screening to detect mutations in cancer. Commonly used technologies are PCR, RT-PCR, high-throughput sequencing, and metabolomic analysis. Conclusions: Currently, tissue biopsies provide increased diagnostic value compared to liquid biopsy. However, the minimal invasiveness and convenience of liquid biopsy make it a suitable method for mass screening and eventual clinical adoption. The analysis of samples includes histological and molecular analysis. Metabolite analysis is rising but remains scarce.

Assessment of Contralateral Biopsy Technique for Improving Tissue Changes in Patients with Tongue Malignancy

Background: Oral cancer is one of the most common type of head and neck cancer, with a 5 year survival rate of < 50%. One of the major problems of oral cancer include the late stage of disease at the time of diagnosis. Mirror image biopsy is a new technique that can be used for detection of early changes in the oral mucosa. Aim of the study: To histologically assess the reflect copy biopsy occupied from clinically usual observing mucosa at consistent contralateral  anatomical place to the main lesion in patients identified with tongue squamous cell carcinoma to notice any indication of arena alteration in oral mucosa. Materials and methods: Seven patients diagnosed with squamous cell carcinoma of the tongue underwent reflect copy biopsy from clinically usual observing mucosa at consistent contralateral anatomical place to the main lesion. The reflect copy biopsy example were exposed to histopathological check. Results: of the seven patients included, four were male and three were female, with an age range from 45 years to 64 years (median 54.5 years). One of the biopsies revealed severe dysplasia and six-revealed hyperplasia of the epithelium. Conclusion: Mirror image biopsy is a useful tool to detect the early field changes in oral mucosa in order to prevent further progression to oral cancer.

Diagnostic tests for oral cancer and potentially malignant disorders in patients presenting with clinically evident lesions

BACKGROUND

Squamous cell carcinoma is the most common form of malignancy of the oral cavity, and is often proceeded by oral potentially malignant disorders (OPMD). Early detection of oral cavity squamous cell carcinoma (oral cancer) can improve survival rates. The current diagnostic standard of surgical biopsy with histology is painful for patients and involves a delay in order to process the tissue and render a histological diagnosis; other diagnostic tests are available that are less invasive and some are able to provide immediate results. This is an update of a Cochrane Review first published in 2015.

OBJECTIVES

Primary objective: to estimate the diagnostic accuracy of index tests for the detection of oral cancer and OPMD, in people presenting with clinically evident suspicious and innocuous lesions.

SECONDARY OBJECTIVE

to estimate the relative accuracy of the different index tests.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the following databases: MEDLINE Ovid (1946 to 20 October 2020), and Embase Ovid (1980 to 20 October 2020). The US National Institutes of Health Ongoing Trials Register (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were also searched for ongoing trials to 20 October 2020. No restrictions were placed on the language or date of publication when searching the electronic databases. We conducted citation searches, and screened reference lists of included studies for additional references.

SELECTION CRITERIA

We selected studies that reported the diagnostic test accuracy of the following index tests when used as an adjunct to conventional oral examination in detecting OPMD or oral cavity squamous cell carcinoma: vital staining (a dye to stain oral mucosa tissues), oral cytology, light-based detection and oral spectroscopy, blood or saliva analysis (which test for the presence of biomarkers in blood or saliva).

DATA COLLECTION AND ANALYSIS

Two review authors independently screened titles and abstracts for relevance. Eligibility, data extraction and quality assessment were carried out by at least two authors, independently and in duplicate. Studies were assessed for methodological quality using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2). Meta-analysis was used to combine the results of studies for each index test using the bivariate approach to estimate the expected values of sensitivity and specificity.

MAIN RESULTS

This update included 63 studies (79 datasets) published between 1980 and 2020 evaluating 7942 lesions for the quantitative meta-analysis. These studies evaluated the diagnostic accuracy of conventional oral examination with: vital staining (22 datasets), oral cytology (24 datasets), light-based detection or oral spectroscopy (24 datasets). Nine datasets assessed two combined index tests. There were no eligible diagnostic accuracy studies evaluating blood or salivary sample analysis. Two studies were classed as being at low risk of bias across all domains, and 33 studies were at low concern for applicability across the three domains, where patient selection, the index test, and the reference standard used were generalisable across the population attending secondary care. The summary estimates obtained from the meta-analysis were: - vital staining: sensitivity 0.86 (95% confidence interval (CI) 0.79 to 0.90) specificity 0.68 (95% CI 0.58 to 0.77), 20 studies, sensitivity low-certainty evidence, specificity very low-certainty evidence; - oral cytology: sensitivity 0.90 (95% CI 0.82 to 0.94) specificity 0.94 (95% CI 0.88 to 0.97), 20 studies, sensitivity moderate-certainty evidence, specificity moderate-certainty evidence; - light-based: sensitivity 0.87 (95% CI 0.78 to 0.93) specificity 0.50 (95% CI 0.32 to 0.68), 23 studies, sensitivity low-certainty evidence, specificity very low-certainty evidence; and - combined tests: sensitivity 0.78 (95% CI 0.45 to 0.94) specificity 0.71 (95% CI 0.53 to 0.84), 9 studies, sensitivity very low-certainty evidence, specificity very low-certainty evidence.

AUTHORS' CONCLUSIONS

At present none of the adjunctive tests can be recommended as a replacement for the currently used standard of a surgical biopsy and histological assessment. Given the relatively high values of the summary estimates of sensitivity and specificity for oral cytology, this would appear to offer the most potential. Combined adjunctive tests involving cytology warrant further investigation. Potentially eligible studies of blood and salivary biomarkers were excluded from the review as they were of a case-control design and therefore ineligible. In the absence of substantial improvement in the tests evaluated in this updated review, further research into biomarkers may be warranted.

Establishing the accuracy of a new and cheaper sample collection tool: Oral cytology versus oral histopathology

Objective:

High cost of tools used for the collection of oral cytology sample; deters their use as mass screening tool in the developing countries. Hence, this study aims to assess the diagnostic accuracy of a new, cheaper sample collection tool in the field of oral exfoliative cytology through comparison with histopathology.

Materials and Methods:

Fifty-seven patients out of 394 cases were selected for the study in whom the cytological examination was performed using the wooden end of a sterile cotton swab followed by biopsy. The cytological smear classified in accordance with the Pap classification was compared with the histopathological diagnosis.

Results:

The study recruited 11 cases of oral potentially malignant disorders, 33 cases of oral carcinomas, and 13 cases of other lesions. The sensitivity and specificity of the cytology test using the wooden end of a sterile cotton swab was 75.0% and 61.5%, respectively. The Spearman's correlation coefficient was 0.618, with the P < 0.01.

Conclusion:

Our study proves that the use of wooden end of a sterile cotton swab stick offers a low cost and fairly effective solution which is not only easily available but can be potentially applied as a mass screening tool at primary health-care centers.

Adjuncts for the evaluation of potentially malignant disorders in the oral cavity: Diagnostic test accuracy systematic review and meta-analysis-a report of the American Dental Association

BACKGROUND

Oral squamous cell carcinoma is the most common manifestation of malignancy in the oral cavity. Adjuncts are available for clinicians to evaluate lesions that seem potentially malignant. In this systematic review, the authors summarized the available evidence on patient-important outcomes, diagnostic test accuracy (DTA), and patients' values and preferences (PVPs) when using adjuncts for the evaluation of clinically evident lesions in the oral cavity.

TYPES OF STUDIES REVIEWED

The authors searched for preexisting systematic reviews and assessed their quality using the Assessing the Methodological Quality of Systematic Reviews tool. The authors updated the selected reviews and searched MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials to identify randomized controlled trials and DTA and PVPs studies. Pairs of reviewers independently conducted study selection, data extraction, and assessment of the certainty in the evidence by using the Grading of Recommendations Assessment, Development and Evaluation approach.

RESULTS

The authors identified 4 existing reviews. DTA reviews included 37 studies. The authors retrieved 7,534 records, of which 9 DTA and 10 PVPs studies were eligible. Pooled sensitivity and specificity of adjuncts ranged from 0.39 to 0.96 for the evaluation of innocuous lesions and from 0.31 to 0.95 for the evaluation of suspicious lesions. Cytologic testing used in suspicious lesions appears to have the highest accuracy among adjuncts (sensitivity, 0.92; 95% confidence interval, 0.86 to 0.98; specificity, 0.94; 95% confidence interval, 0.88 to 0.99; low-quality evidence).

CONCLUSIONS AND PRACTICAL IMPLICATIONS

Cytologic testing appears to be the most accurate adjunct among those included in this review. The main concerns are the high rate of false-positive results and serious issues of risk of bias and indirectness of the evidence. Clinicians should remain skeptical about the potential benefit of any adjunct in clinical practice.

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.

Assessment of cellular and serum proteome from tongue squamous cell carcinoma patient lacking addictive proclivities for tobacco, betel nut, and alcohol: Case study

The intriguing molecular pathways involved in oral carcinogenesis are still ambiguous. The oral squamous cell carcinoma (OSCC) ranks as the most common type constituting more than 90% of the globally diagnosed oral cancers cases. The elevation in the OSCC incidence rate during past 10 years has an alarming impression on human healthcare. The major challenges associated with OSCC include delayed diagnosis, high metastatic rates, and low 5-year survival rates. The present work foundations on reverse genetic strategy and involves the identification of genes showing expressional variability in an OSCC case lacking addictive proclivities for tobacco, betel nut, and/or alcohol, major etiologies. The expression modulations in the identified genes were analyzed in 16 patients comprising oral pre-cancer and cancer histo-pathologies. The genes SCCA1 and KRT1 were found to down regulate while DNAJC13, GIPC2, MRPL17, IG-Vreg, SSFA2, and UPF0415 upregulated in the oral pre-cancer and cancer pathologies, implicating the genes as crucial players in oral carcinogenesis.

Comparison of 3 corneal cytology collection methods for evaluating equine ulcerative keratitis: Cytobrush, kimura platinum spatula, and handle edge of scalpel blade

PURPOSE

To compare corneal cytology samples from three common sampling techniques: cytobrush (CB), Kimura platinum spatula (KS), and the handle edge of a scalpel blade (SB).

METHODS

Equine patients presenting to the University of Florida College of Veterinary Medicine with ulcerative keratitis were included. Following diagnosis of corneal ulcer and sampling for microbial culture, two cytology samples per technique were collected with sterile CB, KS, and SB in a randomized order. Cytologic evaluation was performed by two observers masked to collection method. Objective measures of sample cellularity, quality, distribution, and identification of infectious organisms were recorded per 10 monolayer cell populations using 50× magnification with oil immersion which were compared to culture results. Variables were compared using ANOVA with Student's t test when appropriate and Cohen's kappa (k) to evaluate inter- and intra-observer agreement (IOA) between observers and techniques.

RESULTS

Twenty equine patients (120 samples) were included. The IOA between observers was substantial (k = 0.75 ± 0.06) for cytological parameters. SB provided the most cellular samples (P < .01). There was a trend toward agreement (k = 0.12 ± 0.16) in technique for sample quality (P = .08). CB and SB had significantly poorer cell distribution than KS (P < .05). Infection was confirmed in 12 of 20 patients with SB and CB techniques having a significantly higher diagnostic yield than KS (P < .05) and was most consistent with infection confirmed on culture.

CONCLUSIONS

The SB provided the most diagnostic samples but all three techniques are clinically useful in evaluating equine ulcerative keratitis.