Diagnosis of oral squamous cell carcinoma and its precursor lesions

Automatic Detection of Oral Squamous Cell Carcinoma from Histopathological Images of Oral Mucosa Using Deep Convolutional Neural Network

Worldwide, oral cancer is the sixth most common type of cancer. India is in 2nd position, with the highest number of oral cancer patients. To the population of oral cancer patients, India contributes to almost one-third of the total count. Among several types of oral cancer, the most common and dominant one is oral squamous cell carcinoma (OSCC). The major reason for oral cancer is tobacco consumption, excessive alcohol consumption, unhygienic mouth condition, betel quid eating, viral infection (namely human papillomavirus), etc. The early detection of oral cancer type OSCC, in its preliminary stage, gives more chances for better treatment and proper therapy. In this paper, author proposes a convolutional neural network model, for the automatic and early detection of OSCC, and for experimental purposes, histopathological oral cancer images are considered. The proposed model is compared and analyzed with state-of-the-art deep learning models like VGG16, VGG19, Alexnet, ResNet50, ResNet101, Mobile Net and Inception Net. The proposed model achieved a cross-validation accuracy of 97.82%, which indicates the suitability of the proposed approach for the automatic classification of oral cancer data.

Autofluorescence Image-Guided Endoscopy in the Management of Upper Aerodigestive Tract Tumors

At this juncture, autofluorescence and narrow-band imaging have resurfaced in the medicine arena in parallel with current technology advancement. The emergence of newly developed optical instrumentation in addition to the discovery of new fluorescence biomolecules have contributed to a refined management of diseases and tumors, especially in the management of upper aerodigestive tract tumors. The advancement in multispectral imaging and micro-endoscopy has also escalated the trends further in the setting of the management of this tumor, in order to gain not only the best treatment outcomes but also facilitate early tumor diagnosis. This includes the usage of autofluorescence endoscopy for screening, diagnosis and treatment of this tumor. This is crucial, as microtumoral deposit at the periphery of the gross tumor can be only assessed via an enhanced endoscopy and even more precisely with autofluorescence endoscopic techniques. Overall, with this new technique, optimum management can be achieved for these patients. Hence, the treatment outcomes can be improved and patients are able to attain better prognosis and survival.

Multistage classification of oral histopathological images using improved residual network

Oral cancer is a prevalent disease happening in the head and neck region. Due to the high occurrence rate and serious consequences of oral cancer, an accurate diagnosis of malignant oral tumors is a major priority. Thus, early diagnosis is very effective to give the patient a prompt response to treatment. The most efficient way for diagnosing oral cancer is from histopathological imaging, which provides a detailed view of inside cells. Accurate and automatic classification of oral histopathological images remains a difficult task due to the complex nature of cell images, staining methods, and imaging conditions. The use of deep learning in imaging techniques and computational diagnostics can assist doctors and physicians in automatically analysing Oral Squamous Cell Carcinoma biopsy images in a timely and efficient manner. Thus, it reduces the operational workload of the pathologist and enhance patient management. Training deeper neural networks takes considerable time and requires a lot of computing resources, due to the complexity of the network and the gradient diffusion problem. With this motivation and inspired by ResNet's significant successes to handle the gradient diffusion problem, in this study we suggest the novel improved ResNet-based model for the automated multistage classification of oral histopathology images. Three prospective candidate model blocks are presented, analyzed, and the best candidate model is chosen as the optimal one which can efficiently classify the oral lesions into well-differentiated, moderately-differentiated and poorly-differentiated in significantly reduced time, with 97.59% accuracy.

Long non-coding RNA TTN-AS1/microRNA-199a-3p/runt-related transcription factor 1 gene axis regulates the progression of oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) has a high degree of malignancy, which affects the quality of life and prognosis of patients with OSCC. Our study aimed to reveal the function of long non-coding RNA TTN-AS1/microRNA-199a-3p (miR-199a-3p)/runt-related transcription factor 1 (RUNX1) axis in OSCC progression, thereby providing a novel OSCC effective strategy. Real-time quantitative polymerase chain reaction and western blotting were performed to detect the expression of TTN-AS1, miR-199a-3p, and RUNX1 in OSCC. Several cell functional experiments, including Cell Counting Kit-8, flow cytometry, and cell adhesion assays, were used to assess cell proliferation, apoptosis, adhesion, and migration. A luciferase assay was performed to confirm the interaction between TTN-AS1, miR-199a-3p, and RUNX1. Our results revealed that TTN-AS1 and RUNX1 were upregulated in OSCC tissues and cells, whereas miR-199a-3p expression was downregulated. Knockdown of TTN-AS1 or RUNX1 suppressed cell proliferation, adhesion, and migration but induced apoptosis. Additionally, miR-199a-3p inhibitor partly relieved the effects of silencing TTN-AS1 and RUNX1 in OSCC cells due to their targeting relationship. In conclusion, TTN-AS1 and RUNX1 could promote OSCC progression and miR-199a-3p partly relieved the effects of TTN-AS1 and RUNX1.

A systematic scoping review on utility of cytomorphometry in the detection of dysplasia in oral potentially malignant disorders

Background

Oral exfoliative cytology is simple, non-invasive, inexpensive tools prone to subjective bias. Objective computer-based quantitative cytomorphometry technique was developed in last few decades to overcome its limitation. However, there is no consensus about the utility of cytomorphometry as a routine screening tool for early detection of dysplastic changes.

Objectives

To review the utility of cytomorphometry in OPMDs in the detection of dysplasia changes.

Method

A scoping review was undertaken focusing on cytomorphometric analysis in exfoliative cells for detection of oral epithelial dysplasia and cytomorphometric parameter denoting dysplasia. The systematic search was carried out in the online journal databases (Scopus, Google Scholar, PubMed, Web of Science) using keywords until December 2019 for the studies evaluated the cytomorphometry in the detection of dysplastic changes in OPMDs. Three authors independently extracted data using collection forms.

Result

The search strategy found seven analytical cross-sectional studies for scoping review after eliminating 8940 out of 8947 initial results. The scoping review showed that cytomorphometry is useful tool in detecting the dysplastic changes in OPMDs. In addition, decrease in mean cellular area, increase in mean nuclear area, and decrease in mean cell diameter, increase mean nuclear diameter, increase in mean nuclear and cytoplasmic area ratio, associated with development of dysplastic changes in OPMDs.

Conclusion

Cytomorphometry is promising tool, yet there is currently no-good evidence to support role of cytomorphometry in detecting the dysplastic changes in OPMDs in this setting. More research is required for refinement of cytomorphometry as a screening tool.

Minimally invasive procedures for the recognition and diagnosis of oral precancer and cancer

Oral cancer represents a blend of genetic and epigenetic instability. Many a times, oral cancer occurs in the background of oral potentially malignant disorders (OPMDs), which could be easily detected and diagnosed. Various diagnostic aids have been explored for early detection of oral cancer. Some of the minimally invasive (chair-side diagnostic) procedures such as vital staining and light-based systems are used widely in the clinical practice as well as in the hospital setting owing to their simple and easy operability. In addition, these chair-side diagnostic procedures offer relatively good sensitivity and specificity despite some of their limitations. These diagnostic tools could complement good clinical history and thorough examination of patients for early detection of oral precancer and cancer.

Oral Brush Liquid-Based Cytology: A Study of Concordance between a Cytotechnologist and a Cytopathologist

OBJECTIVE

Oral cancer accounts for almost 40% of all cancers in the Indian subcontinent. Techniques like oral scrape cytology are helpful in early diagnosis of premalignant lesion and thus prevention of malignant transformation. The purpose of this study is to evaluate the performance of cytotechnologists in assessing the adequacy and preliminary diagnostic accuracy of oral brush liquid-based cytology.

STUDY DESIGN

110 oral brush liquid-based cytology smears were prospectively screened by a cytotechnologist for adequacy assessment, and a preliminary diagnosis was recorded. Smears were subsequently studied by the reporting cytopathologist for the final diagnosis. The performance of the cytotechnologist in the assessment of adequacy and the preliminary diagnosis were compared with the final interpretation rendered by the cytopathologist.

RESULTS

There was no significant difference in adequacy assessment between both observers, and good concordance was observed in the identification of frankly malignant lesions; however, in premalignant cases, complete agreement in all the cases was not observed. Maximum numbers of discrepant cases were seen in high-grade squamous intraepithelial lesions, 4/17 were downgraded to low-grade squamous intraepithelial lesions and 2/17 to negative for intraepithelial lesion or malignancy, respectively.

CONCLUSION

Trained cytotechnologists are capable of assessing the adequacy and identifying the malignancy in oral brush liquid-based cytology smears, and hence there is potential for them to perform initial screening of such cases.

Frequency of Delayed Diagnosis of Oral Squamous Cell Carcinoma in Pakistan

Objectives:

To determine the frequency of delayed diagnosis of oral squamous cell carcinoma in our setup; highlighting factors responsible for any delay and their possible relevance to demographic and diagnostic features.

Methods:

This cross sectional study of six months duration was conducted in the Oral and Maxillofacial Surgery Department of the Armed Forces Institute of Dentistry, Rawalpindi, Pakistan. A total of 246 patients, both male and female, having a biopsy proven definitive diagnosis of OSCC were included using a consecutive sampling technique. Delay in diagnosis was assessed from the stated period of time from when the patient first noticed symptoms of disease until a definitive diagnosis was made. We concluded delayed diagnosis if this was more than 40 days.

Results:

The ages of patients ranged from 27 to 60 years with a mean of 46.7 ± 10.2 years and a marked male predominance (3.7:1). Delayed diagnosis was observed in 91.5% of cases. However, statistically no significant differences were found with age, gender, marital, education status, household income and time of biopsy.

Conclusion:

Our primary finding of delayed diagnosis with no prior contact with any health care professional clearly reflects a need of taking urgent measures to avoid serious impacts on morbidity and mortality associated with OSCC.

The prognostic value of GLUT-1 staining in the detection of malignant transformation in oral mucosa

BACKGROUND

Head and neck squamous cell carcinoma (HNSCC) ranks as the sixth most common tumor entity worldwide. Unfortunately, the multimodal treatment consisting of surgery, radiation, and chemotherapy does not show the desired efficacy. The intent of this study was to evaluate the sensitivity and specificity of an oral brush biopsy in combination with glucose transporter (GLUT)-1 staining in identifying premalignant and malignant lesions.

METHODS

A total of 72 patients were included in the study, divided into four diagnostic subgroups (24 healthy, 15 carcinoma, 18 leukoplakia, 15 oral lichen planus). Oral brush biopsies were taken and analyzed for GLUT-1 expression by immunocytologic staining. Incisional biopsy served as the gold standard.

RESULTS

Twelve (80 %) of the 15 carcinomas, nine (50 %) of the 18 leukoplakia, nine (60 %) of the 15 oral lichen planus, and none of the healthy specimens stained positive for GLUT-1. This resulted in a sensitivity rate of 80 % and a specificity rate of 68.42 %. Diagnostic accuracy was 70.83 % based on the correct diagnoses in 51 of 72 patients.

CONCLUSION

An oral brush biopsy can easily be performed throughout the entire oral cavity, is noninvasive, and shows high sensitivity and specificity rates with conventional cytology or computer-assisted analysis.

CLINICAL RELEVANCE

The significance of GLUT-1-specific staining with an oral brush biopsy is more limited than expected but could be used as an additional tool in detecting malignant transformation in the oral cavity.

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

BACKGROUND

The use of oral cytology to diagnose malignant and premalignant lesions at an early stage is considered crucial. The aim of this study was to evaluate the diagnoses of the spatula and the cytobrush techniques compared with the gold standard histopathological findings, analysed according to different diagnostic criteria.

METHODS

Cytological smears were obtained from 76 suspicious oral malignant lesions and 116 oral leukoplakia lesions using two techniques: cytobrush plus cell collector and metal spatula. Subsequently, a surgical biopsy was performed on each lesion to achieve a histopathological diagnosis. Evaluation was conducted with respect to three different diagnostic criteria.

RESULTS

The sensitivity for diagnosing carcinoma in clinically malignant cases was 89.58% and 60.42% for cytobrush and spatula techniques, respectively. Inclusion of severe dysplastic cases for 'high-risk' lesions increased the sensitivity up to 96.36% and 78.18% for two techniques, respectively. In leukoplakia lesions, malignant and severely dysplastic cells were diagnosed at a sensitivity of 88.89% in the cytobrush and 55.56% in the spatula techniques. Extending the criteria by defining malignant or any dysplastic findings as positive, sensitivity was increased to 98.02% and 89.11% for the spatula and the cytobrush techniques, respectively. Specificity for both techniques increased to 100%. The difference between the diagnoses of histopathology and the spatula cytology was statistically significant (P < 0.01), while no such difference was found with the cytobrush technique (P > 0.1).

CONCLUSION

The cytobrush, unlike the spatula, is a useful screening instrument for early diagnosis of suspicious oral lesions and could therefore contribute to improved oral cancer prognosis.

Correlation of clinical, cytological and histological findings in oral squamous cell carcinomas

The present study aimed to investigate the efficiency of exfoliative cytology by correlating the clinical lesions of oral squamous cell carcinoma (OSCC) with exfoliative cytology and histopathological findings. Cases of OSCC diagnosed between 1984 and 2010 were analyzed. The inclusion criteria for the present study were the availability of detailed clinical findings and a diagnosis of the disease through exfoliative cytology and histopathology. The cases were assessed and assigned scores, which were then submitted to modal expression analysis, which considers the higher frequency scores, thus relating the variables. The cytological findings demonstrated that the majority of the cases had malignant potential. Exfoliative cytology should be used as a supplementary tool for the diagnosis of OSCC, as it enables the early detection of these lesions. However, cytology should not be used as a substitute for histopathological examination.

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.

Evaluation of chemiluminescence, toluidine blue and histopathology for detection of high risk oral precancerous lesions: A cross-sectional study

Background

Early detection holds the key to an effective control of cancers in general and of oral cancers in particular. However, screening procedures for oral cancer are not straightforward due to procedural requirements as well as feasibility issues, especially in resource-limited countries.

Methods

We conducted a cross-sectional study to compare the performance of chemiluminescence, toluidine blue and histopathology for detection of high-risk precancerous oral lesions. We evaluated 99 lesions from 55 patients who underwent chemiluminescence and toluidine blue tests along with biopsy and histopathological examination. We studied inter-as well as intra-rater agreement in the histopathological evaluation and then using latent class modeling, we estimated the operating characteristics of these tests in the absence of a reference standard test.

Results

There was a weak inter-rater agreement (kappa < 0.15) as well as a weak intra-rater reproducibility (Pearson's r = 0.28, intra-class correlation rho = 0.03) in the histopathological evaluation of potentially high-risk precancerous lesions. When compared to histopathology, chemiluminescence and toluidine blue retention had a sensitivity of 1.00 and 0.59, respectively and a specificity of 0.01 and 0.79, respectively. However, latent class analysis indicated a low sensitivity (0.37) and high specificity (0.90) of histopathological evaluation. Toluidine blue had a near perfect high sensitivity and specificity for detection of high-risk lesions.

Conclusion

In our study, there was variability in the histopathological evaluation of oral precancerous lesions. Our results indicate that toluidine blue retention test may be better suited than chemiluminescence to detect high-risk oral precancerous lesions in a high-prevalence and low-resource setting like India.

Perspectives of San Juan healthcare practitioners on the detection deficit in oral premalignant and early cancers in Puerto Rico: a qualitative research study

Background

In Puerto Rico, relative to the United States, a disparity exists in detecting oral precancers and early cancers. To identify factors leading to the deficit in early detection, we obtained the perspectives of San Juan healthcare practitioners whose practice could be involved in the detection of such oral lesions.

Methods

Key informant (KI) interviews were conducted with ten clinicians practicing in or around San Juan, Puerto Rico. We then triangulated our KI interview findings with other data sources, including recent literature on oral cancer detection from various geographic areas, current curricula at the University of Puerto Rico Schools of Medicine and Dental Medicine, as well as local health insurance regulations.

Results

Key informant-identified factors that likely contribute to the detection deficit include: many practitioners are deficient in knowledge regarding oral cancer and precancer; oral cancer screening examinations are limited regarding which patients receive them and the elements included. In Puerto Rico, specialists generally perform oral biopsies, and patient referral can be delayed by various factors, including government-subsidized health insurance, often referred to as Reforma. Reforma-based issues include often inadequate clinician knowledge regarding Reforma requirements/provisions, diagnostic delays related to Reforma bureaucracy, and among primary physicians, a perceived financial disincentive in referring Reforma patients.

Conclusions

Addressing these issues may be useful in reducing the deficit in detecting oral precancers and early oral cancer in Puerto Rico.

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.

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.

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.

[Screening and diagnosis of precancerous oral mucosa lesions]

The screening and early diagnosis of cancerous oral mucosa lesions are still key elements for a better prognosis. Therefore, it is of tremendous importance to try to determine how and when to diagnose precancerous oral mucosa lesions. Usually, clinical examination data must be completed by a pathological examination. This study, based on an exhaustive literature review, has for purpose to determine the sensitivity and specificity of complementary diagnostic tools currently available.

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.

Searching for metachronous tumours in patients with head and neck cancer: the ideal protocol!

PURPOSE OF REVIEW

As treatment changes in the management of head and neck cancer, patients are reportedly living longer; therefore, their death may be due to comorbidity, metastatic disease or the development of a metachronous second primary tumour (MSPT). This review describes recent developments in the identification of MSPTs of head and neck cancer, oesophagus and lung, and suggests/recommends an 'ideal surveillance protocol'.

RECENT FINDINGS

The rate of MSPT development ranges between 6 and 9% annually for life. Improved accuracy in the detection of mucosal asymptomatic premalignant and early cancer has been enhanced by incorporating fluorescence spectroscopy in addition to modern flexible endoscopic techniques in the outpatient setting. Newer imaging has replaced old techniques (chest radiograph, barium swallow, etc.) by using radiotracer PET-computed tomography to detect local tumour activity. Further advances are anticipated in optical diagnostics and the incorporation of radiopharmaceuticals with labelled antibodies to enhance PET imaging, thus making tumour identification more accurate. Genetic classification of head and neck cancer has already identified high-risk patient groups, thereby allowing expensive tumour screening techniques to be used selectively and specifically. Patients who continue to smoke and abuse alcohol must be helped and encouraged to quit.

SUMMARY

It is now possible to review traditional follow-up policy for treated head and neck cancer patients, to encourage the implementation of an evidence-based surveillance protocol, to identify only patients who are at high-risk of developing a MSPT, to incorporate modern targeted expensive tumour screening and to allow treatment of early cancer and effective treatment, thereby improving patients' quality of life and increasing survival.

MAGE-A antigens in lesions of the oral mucosa

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

Adjunctive techniques for oral cancer examination and lesion diagnosis: a systematic review of the literature

BACKGROUND

Adjunctive techniques that may facilitate the early detection of oral premalignant and malignant lesions (OPML) have emerged in the past decades.

METHODS

The authors undertook a systematic review of the English-language literature to evaluate the effectiveness of toluidine blue (TB), ViziLite Plus with TBlue (Zila Pharmaceuticals, Phoenix), ViziLite (Zila Pharmaceuticals), Microlux DL (AdDent, Danbury, Conn.), Orascoptic DK (Orascoptic, a Kerr Company, Middleton, Wis.), VELscope (LED Dental, White Rock, British Columbia, Canada) and OralCDx (Oral CDx Laboratories, Suffern, N.Y.) brush biopsy. They abstracted data relating to study design, sampling and characteristics of the study group, interventions, reported outcomes and diagnostic accuracy of adjunctive aids from 23 articles meeting inclusion and exclusion criteria, including availability of histologic outcomes.

RESULTS

The largest evidence base was for TB. A limited number of studies was available for ViziLite, ViziLite Plus with TBlue and OralCDx. Studies of VELscope have been conducted primarily to assess the margins of lesions in known OPML. The authors identified no studies of Microlux DL or Orascoptic DK. Study designs had various limitations in applicability to the general practice setting, including use of higher-risk populations and expert examiners.

CONCLUSIONS

There is evidence that TB is effective as a diagnostic adjunct for use in high-risk populations and suspicious mucosal lesions. OralCDx is useful in assessment of dysplastic changes in clinically suspicious lesions; however, there are insufficient data meeting the inclusion criteria to assess usefulness in innocuous mucosal lesions. Overall, there is insufficient evidence to support or refute the use of visually based examination adjuncts. Practical Implications. Given the lack of data on the effectiveness of adjunctive cancer detection techniques in general dental practice settings, clinicians must rely on a thorough oral mucosal examination supported by specialty referral and/or tissue biopsy for OPML diagnosis.