Biopsy of the sentinel lymph node in oral squamous cell carcinoma: analysis of error in 100 consecutive cases.

UK national guidelines in 2016 recommended that sentinel lymph node biopsy should be offered to patients with early oral cancer (T1-T2 N0) in which the primary site can be reconstructed directly. This study describes the pitfalls that can be avoided in the technique of biopsy to improve outcomes. We retrospectively analysed the data from 100 consecutive patients and recorded any adverse events. Lymphatic drainage of tracer failed in two patients as a result of procedural errors. Two patients with invaded nodes developed recurrence after total neck dissection, one after micrometastases had been diagnosed, and the other as a result of extranodal spread that had led to understaging and therefore undertreatment. Two results would not have been mistakenly classified as clear if all the harvested nodes had been analysed histologically according to the protocol. The disease-specific (96%) and disease-free (92%) survival were better than expected for a group of whom a third had stage 3 disease. If all harvested nodes had been analysed by the correct protocol then two of the three nodes wrongly designated clear would have been detected, two deaths potentially avoided, and the false-negative rate would have fallen from 8.3% to 2.7%. We conclude that minor deviations from protocol can result in a detrimental outcome for the patient.

Epithelioid Haemangioendothelioma of the mandibular gingiva: case report and literature review.

INTRODUCTION: Epithelioid hemangioendothelioma (EHE) is a rare vascular neoplasm that exhibits the potential for recurrence and metastasis but rarely involves the oral cavity. PRESENTATION OF CASE: We report the management and long term follow up of recurrent EHE in a 23- year-old woman. The lesion initially presented as a small area of erythematous gingival swelling with localised bone loss around the lower anterior teeth. It was treated by buccal and lingual stripping of the gingival tissues. The patient suffered local recurrence after 7 years and was treated with a wider surgical excision of the buccal and lingual gingivae, conserving the adjacent teeth and bone with an excellent cosmetic outcome. Over 21 years later, there have been no further recurrences. DISCUSSION: This case highlights the management challenges of EHE and is the only case in the literature to have reported a case of mandibular gingivae with a long review period of 21 years. CONCLUSION: Oral EHE is an unpredictable lesion with a relatively benign course, unlike non-oral EHE where up to one third of cases may metastasise. Because of the propensity to recur locally after excision and curettage, a wide local excision with close clinical follow has been suggested in the literature as the treatment of choice for oral lesions. However, the lack of metastases from oral lesions, the small size, mandibular site and bland histology in this case suggests that a limited soft tissue excision and bone curettage, with long term follow-up would be appropriate for similar gingival lesions in future.

Correlation between Ki-67 immunohistochemistry and 18F-fluorothymidine uptake in patients with cancer: A systematic review and meta-analysis.

BACKGROUND: Positron emission tomography (PET) imaging using the radiotracer 18F-Fluorothymidine (FLT) has been proposed as an imaging biomarker of tumour proliferation. If FLT-PET can be established as such it will provide a non-invasive, quantitative measurement of tumour proliferation across the entire tumour. Results from validation studies have so far been conflicting with some studies confirming a good correlation between FLT uptake and Ki-67 score and others presenting negative results. METHODS: Firstly we performed a systematic review of published studies between 1998 and 2011 that explored the correlation between FLT uptake and Ki-67 score and examined possible variations in the methods used. Studies were eligible if they: (a) included patients with cancer, (b) investigated the correlation between Ki-67 measured by immunohistochemistry and FLT uptake measured with PET scanning, and (c) were published as a full paper in a peer-reviewed scientific journal. Secondly a meta-analysis of the correlation coefficient values reported from each study was performed. Correlation coefficient (r) values were extracted from each study and 95% confidence intervals (CIs) were calculated after applying Fisher's z transformation. For subgroup analysis, studies were classified by the index used to characterise Ki-67 expression (average or maximum expression), the nature of the sample (whole specimen or biopsy) and the cancer type. FINDINGS: Twenty-seven studies were identified as eligible for the meta-analysis. In the studies we examined there were variations in aspects of the methods and reporting. The meta-analysis showed that given an appropriate study design the FLT/Ki-67 correlation is significant and independent of cancer type. Specifically subgroup analysis showed that FLT/Ki-67 correlation was high in studies measuring the Ki-67 average expression regardless of use of surgery or biopsy samples (r=0.70, 95% CI=0.43-0.86, p<0.001). Of the studies that measured Ki-67 maximum expression, only those that used the whole surgical specimen provided a significant r value (r=0.72, 95% CI=0.54-0.84, p<0.001). Studies that used biopsy samples for Ki-67 maximum measurements did not produce a significant r value (r=0.04, 95% CI=-0.18-0.26, p=0.71). In terms of the cancer type subgroup analysis there is sufficient data to support a strong FLT/Ki-67 correlation for brain, lung and breast cancer. No publication bias was detected. INTERPRETATION: This systematic review and meta-analysis highlights the importance of the methods used in validation studies comparing FLT-PET imaging with the biomarker Ki-67. The correlation is significant and independent of cancer type provided a study design that uses Ki-67 average measurements, regardless of nature of sample, or whole surgical samples when measuring Ki-67 maximum expression. Sufficient data to support a strong correlation for brain, lung and breast cancer exist. However, larger, prospective studies with improved study design are warranted to validate these findings for the rest of the cancer types.

Human Gyrovirus Apoptin shows a similar subcellular distribution pattern and apoptosis induction as the chicken anaemia virus derived VP3/Apoptin.

The chicken anaemia virus-derived protein Apoptin/VP3 (CAV-Apoptin) has the important ability to induce tumour-selective apoptosis in a variety of human cancer cells. Recently the first human Gyrovirus (HGyV) was isolated from a human skin swab. It shows significant structural and organisational resemblance to CAV and encodes a homologue of CAV-Apoptin/VP3. Using overlapping primers we constructed a synthetic human Gyrovirus Apoptin (HGyV-Apoptin) fused to green fluorescent protein in order to compare its apoptotic function in various human cancer cell lines to CAV-Apoptin. HGyV-Apoptin displayed a similar subcellular expression pattern as observed for CAV-Apoptin, marked by translocation to the nucleus of cancer cells, although it is predominantly located in the cytosol of normal human cells. Furthermore, expression of either HGyV-Apoptin or CAV-Apoptin in several cancer cell lines triggered apoptosis at comparable levels. These findings indicate a potential anti-cancer role for HGyV-Apoptin.

Apoptin induces apoptosis by changing the equilibrium between the stability of TAp73 and ΔNp73 isoforms through ubiquitin ligase PIR2.

Apoptin, a protein derived from the chicken anaemia virus, induces cell death in various cancer cells but shows little or no cytotoxicity in normal cells. The mechanism of apoptin-induced cell death is currently unknown but it appears to induce apoptosis independent of p53 status. Here we show that p73, a p53 family member, is important in apoptin-induced apoptosis. In p53 deficient and/or mutated cells, apoptin induced the expression of TAp73 leading to the induction of apoptosis. Knockdown of p73 using siRNA resulted in a significant reduction in apoptin-induced cytotoxicity. The p53 and p73 pro-apoptotic target PUMA plays an important role in apoptin-induced cell death as knockdown of PUMA significantly reduced cell sensitivity to apoptin. Importantly, apoptin expression resulted in a marked increase in TAp73 protein stability. Investigation into the mechanisms of TAp73 stability showed that apoptin induced the expression of the ring finger domain ubiquitin ligase PIR2 which is involved in the degradation of the anti-apoptotic ∆Np73 isoform. Collectively, our results suggest a novel mechanism of apoptin-induced apoptosis through increased TAp73 stability and induction of PIR2 resulting in the degradation of ∆Np73 and activation of pro-apoptotic targets such as PUMA causing cancer cell death.

Grading oral epithelial dysplasia: analysis of individual features.

BACKGROUND: Assessing epithelial dysplasia to predict malignant transformation remains problematic in many tissues because grading systems are poorly structured and individual features poorly defined. Dysplasia grading is criticised for lack of reproducibility and poor predictive value. Grading systems for upper aerodigestive tract dysplasia have evolved over several decades and are not supported by good outcome experimental data. METHODS: This study analysed the individual features of dysplasia in 86 oral dysplastic lesions and determined the reproducibility of scoring for each, and correlated them with other features and clinical factors using complex clustering analyses. RESULTS: A uniform pattern of dysplasia was found in 37 lesions, focal dysplasia in 36 and in 13 lesions dysplasia formed complex discontinuous patterns. There was wide variation in reproducibility of scoring of individual features and many, including thickness, some types of rete morphology, basaloid cell anisonucleosis, basal dyscohesion, and dyskeratosis as deep single cells correlated with sub-sites. Rete morphology, type of keratinisation, hyperchromatism of the basaloid compartment, prickle cell anisonucleosis and extension down salivary ducts correlated with smoking. Conventional grading and oral intraepithelial neoplasia (OIN) grading by 'thirds affected' showed strong correlation overall but scores obtained with the OIN system tended to a higher grade at all sites except soft palate/fauces. There was poor correlation between the systems for moderate dysplasia and also severe dysplasia at some sites. Individual features could not be shown to cluster to form distinct patterns of dysplasia. CONCLUSIONS: These variations may account in part for the lack of reproducibility and poor predictive value of the grading systems in current use and could inform the design of future grading systems.

Impact of WWOX alterations on p73, ΔNp73, p53, cell proliferation and DNA ploidy in salivary gland neoplasms.

OBJECTIVE: WWOX gene is altered in a variety of neoplasms. Wwox is pro-apoptotic through interaction with p73 and may be involved in chromosomal stability by interaction with p73 and p53. The aims of this study were to characterize WWOX transcription, methylation status and immunoexpression in salivary neoplasms and to determine whether these were associated with p73, p53, cell proliferation and DNA ploidy. MATERIALS AND METHODS: Seven malignant and 21 benign fresh salivary neoplasms were included. WWOX expression was determined by RT-PCR and sequencing of transcripts, quantitative PCR and immunohistochemistry. Methylation-specific PCR was used to assess the methylation of its first exon. For p73, ΔNp73, p53 and ki67 immunohistochemistry and ploidy analysis, 29 malignant samples from archives were included. RESULTS: No consistent pattern of WWOX exon 1 methylation was found, but aberrant and novel transcripts were observed in 17/28 neoplasms; 55% of tumours showed reduced WWOX RNA. WWOX RNA levels were associated with p53 immunopositivity. Immunohistochemical Wwox expression did not correlate with methylation status, p53 or p73 expression or proliferation. p73, proliferation and DNA ploidy were associated with malignant phenotype. CONCLUSION: Aberrant WWOX transcription and decreased expression are frequent in salivary neoplasms and WWOX transcription is associated with p53 staining.

Abnormal DNA content in oral epithelial dysplasia is associated with increased risk of progression to carcinoma.

BACKGROUND: Oral epithelial dysplasia (OED) is a histologically detectable lesion that may progress to carcinoma but there are no accurate markers that predict progression. This study examined the development of carcinoma from oral dysplastic lesions, and the association between abnormal DNA content and progression to carcinoma. METHODS: Epithelial dysplasias from the Oral Pathology Diagnostic Service were matched against the Ontario Cancer Registry database to identify cases that progressed to carcinoma. A case-control study was conducted to compare DNA image cytometry of dysplasias that progressed with those that have not progressed. For a subset of the progressed dysplasias, DNA content of the carcinoma was also analysed. RESULTS: A total of 8% of epithelial dysplasias progressed to carcinoma after 6-131 months. In all, 28 of 99 dysplasias showed abnormal DNA content by image cytometry. In multivariate analysis of time to progression, abnormal DNA content was a significant predictor with hazard ratio of 3.3 (95% confidence interval: 1.5-7.4) corrected for site and grade of dysplasia. Analysis of sequential samples of dysplasia and carcinoma suggested that epithelial cell populations with grossly abnormal DNA content were transient intermediates during oral cancer development. CONCLUSIONS: Abnormal DNA content is a significant biomarker of a subset of OED that progress to carcinoma.

PML involvement in the p73-mediated E1A-induced suppression of EGFR and induction of apoptosis in head and neck cancers.

Epidermal growth factor receptor (EGFR) tyrosine kinase is commonly overexpressed in human cancers; however, the cellular mechanisms regulating EGFR expression remain unclear. p53, p63 and p73 are transcription factors regulating many cellular targets involved in controlling the cell cycle and apoptosis. p53 activates EGFR expression, whereas TAp63 represses EGFR transcription. The involvement of p73 in the regulation of EGFR has not been reported. Here, a strong correlation between EGFR overexpression and increased levels of the oncogenic DeltaNp73 isoform in head and neck squamous cell carcinoma (HNSCC) cell lines was observed. Ectopic expression of TAp73, particularly TAp73beta, resulted in suppression of the EGFR promoter, significant downregulation of EGFR protein and efficient induction of cell death in all six EGFR-overexpressing HNSCC cell lines. EGFR overexpression from a heterologous LTR promoter protected lung cancer cells from TAp73beta-induced EGFR suppression and apoptosis. Expression of TAp73beta efficiently induced promyelocytic leukaemia (PML) protein expression and PML knockdown by shRNA attenuated the downregulation of EGFR and induction of apoptosis by p73 in HNSCC cells. Furthermore, PML was found to be important for E1A-induced suppression of EGFR and subsequent killing of HNSCC cells. Our data therefore suggest a novel pathway involving PML and p73 in the regulation of EGFR expression.

ERBB receptors in developing, dysplastic and malignant oral epithelia.

Some oral squamous cell carcinomas (OSCCs) overexpress epidermal growth factor receptor (EGFR) but little is known about the receptor system overall during oral carcinogenesis. We studied all four ERBB receptors (EGFR, ERBB2-4) in developing (n=2), normal (n=7), dysplastic (n=23) and malignant (n=26) oral epithelia by means of immunohistochemistry. The investigations were supplemented by conducting reverse transcription-polymerase chain reactions in relation to 13 OSCC samples. All four ERBB receptors were detected in developing oral epithelium and, to a lesser degree, in mature oral epithelium. An increase in EGFR immunoreactivity was seen in 61% and 54% of dysplasias and OSCCs, respectively. The corresponding percentages for ERBB2 were 48 and 12, for ERBB3 48 and 43. ERBB4 nuclear staining was increased in 30% of dysplasias and 26% of OSCCs. Changes in ERBB receptor mRNA levels were not statistically significant. The results show that ERBB receptor profiles are specific to each tumour. Increased nuclear translocation of ERBB4 in some OSCCs may alter transcription of target genes and be associated with cancer progression. This information may be useful for clinicians as EGFR inhibitors are becoming treatment options in modern oncology.

DNA ploidy in proliferative verrucous leukoplakia.

Proliferative verrucous leukoplakia (PVL) is a clinicopathologically distinctive form of oral leukoplakia presenting with multifocal flat, nodular and verrucous lesions that progress inexorably to squamous carcinoma. The aims of this investigation were to describe the clinical and histopathological features of six cases of PVL and to determine whether lesional epithelium demonstrates DNA ploidy anomalies prior to malignant transformation. The clinical and pathological features of six patients were reviewed and all biopsy specimens were subjected to image-based DNA ploidy analysis. The female:male ratio was 5:1 and the average age on first biopsy was 66 years. Only one patient reported both tobacco smoking and alcohol intake. The most frequently affected sites were alveolar ridge and/or gingiva (6/6), buccal mucosa (3/6), palate (3/6), tongue (2/6), buccal sulcus (2/6), and lip (1/6). Three patients developed multiple primary carcinomas, either invasive or verrucous. A ploidy anomaly at any oral site would have predicted malignant transformation in four cases and probably in a fifth for whom DNA ploidy failed to meet diagnostic criteria but was suspicious of aneuploidy. The site of transformation was predicted by ploidy and histopathology for three carcinomas and a further carcinoma showed severe dysplasia and a suspicious ploidy result in adjacent tissue. Both conventional histopathology and DNA ploidy proved effective in predicting the site of transformation in this limited series.

Heterogeneity, histological features and DNA ploidy in oral carcinoma by image-based analysis.

Oral squamous carcinomas appear heterogeneous on DNA ploidy analysis. However, this may be partly a result of sample dilution or the detection limit of techniques. The aim of this study was to determine whether oral squamous carcinomas are heterogeneous for ploidy status using image-based ploidy analysis and to determine whether ploidy status correlates with histological parameters. Multiple samples from 42 oral squamous carcinomas were analysed for DNA ploidy using an image-based system and scored for histological parameters. 22 were uniformly aneuploid, 1 uniformly tetraploid and 3 uniformly diploid. 16 appeared heterogeneous but only 8 appeared to be genuinely heterogeneous when minor ploidy histogram peaks were taken into account. Ploidy was closely related to nuclear pleomorphism but not differentiation. Sample variation, detection limits and diagnostic criteria account for much of the ploidy heterogeneity observed. Confident diagnosis of diploid status in an oral squamous cell carcinoma requires a minimum of 5 samples.

British Society for Oral and Maxillofacial Pathology, UK: minimum curriculum in oral pathology.

This paper describes a minimum curriculum in oral pathology for undergraduate dental education in the United Kingdom prepared by the Teachers Group of The British Society of Oral and Maxillofacial Pathology. Curricular development in UK dental schools is overseen by the General Dental Council (GDC), the Quality Assurance Agency for Higher Education (QAA) and the European Union. These organisations define the framework for education and learning outcomes but provide little or no detailed guidance on syllabus or curriculum. This recommended minimum curriculum has been drawn up by a consensus process involving teachers of oral pathology from all 13 UK and one Irish dental schools and is cross-referenced to the GDC and QAA published requirements for undergraduate dental education.

Clinico-pathological conference 2002.

INTRODUCTION: Six cases are reported, each presented at the 11th Biennial Congress of the International Association of Oral Pathologists as an instructive case for differential diagnosis on the basis of clinical, imaging or histological features. CLINICAL PICTURE: Case diagnoses included a large, possibly intraosseous, myofibroma presenting with an oral mass; Langerhans cell histiocytosis with facial skin lesions; an intraosseous vascular hamartoma of the maxilla with worrying radiological features; an unusual mixed radiolucency of the jaw caused by cemento-ossifying fibroma; an osteosarcoma of the posterior mandible causing a well-defined radiolucency and an intraoral squamous cell carcinoma in a child.

Basal cell adenocarcinoma in minor salivary glands.

Basal cell adenocarcinoma is a rare and relatively recently characterized malignant salivary gland tumour, the malignant counterpart of basal cell adenoma. Diagnosis depends on finding features similar to adenoma but with an infiltrative growth pattern and exclusion of adenoid cystic carcinoma, sialoblastoma and basaloid squamous carcinoma. Basal cell adenocarcinoma is very rarely reported in minor salivary glands. We report three cases of basal cell adenocarcinoma affecting the labial, buccal and palatal minor salivary glands. One recurred following complete removal but with lesional disruption and further local wide excision appeared curative. A further lesion failed to recur in 5 years' follow-up despite marginal excision and a third after 3 years' follow-up. Basal cell adenocarcinoma is considered a low-grade malignancy, and in the minor glands wide excision and radiotherapy are recommended. However, the reported lesions appear to have a more indolent behaviour than previously reported lesions in minor glands.

Expression of ICAM-1 and E-selectin in gingival tissues of smokers and non-smokers with periodontitis.

BACKGROUND: Tobacco smoking affects systemic concentrations of soluble intercellular adhesion molecule (ICAM)-1, but its effect on local expression of adhesion molecules in gingival tissue has not been studied previously. METHODS: E-selectin and ICAM-1 expression on small blood vessel endothelia in gingival biopsies obtained from smokers (n=17) and non-smokers (n=17) with periodontitis was examined with immunohistochemistry. Blood vessels were identified with monoclonal antibody for von Willebrand's factor. RESULTS: A significantly larger number of vessels were observed in inflamed tissues of non-smokers than smokers (P<0.05). The number and proportion of vessels expressing both ICAM-1 and E-selectin was greater in sites with inflammation compared to non-inflamed sites in both smokers and non-smokers (P<0.05). The proportion of the total number of vessels expressing ICAM-1 in non-inflamed sites was greater in non-smokers compared with smokers (P<0.05). CONCLUSIONS: These results suggest that the inflammatory response in smokers with periodontitis may not be accompanied by an equivalent increase in vascularity. Reduced ICAM-1 expression in non-inflamed areas of smokers could reflect a systemic effect of tobacco smoking on ICAM-1 independent of inflammation.

Rapid growth of giant cell granuloma in pregnancy treated with calcitonin.

The giant cell granuloma of the jaws is a benign osteolytic lesion that may be treated by curettage, intralesional corticosteroids, or calcitonin. These medical treatments may be particularly useful when lesions arise in the immature facial skeleton, recur, or enlarge very rapidly-the last two situations being recognized complications of pregnancy. In this study, a patient is presented with a central giant cell lesion of the maxilla that switched from a relatively indolent growth pattern to become a rapidly enlarging and destructive lesion in the maxilla almost immediately after the patient became pregnant. Although calcitonin treatment is normally avoided in pregnancy, it proved highly effective, caused no obstetric or fetal side effects, and was not contraindicated by renal failure due to lupus nephritis. Histologically, the lesion was converted to a fibro-osseous lesion-like appearance. On the basis of the results of this case, calcitonin appears to be a safe, effective, and conservative treatment for giant cell granulomas that enlarge rapidly during pregnancy.

Participating dentists' assessment of the pilot regional online videoconferencing in dentistry (PROVIDENT) project.

OBJECTIVE: To assess the educational effectiveness of delivering continuing professional education (CPE) from dental schools to small groups of dentists at distant sites via videoconferenced links using relatively inexpensive equipment and ISDN2 links. DESIGN: 41 videoconferences between the four campuses of London Dental Schools and postgraduate centres in South East England were assessed using a pre-piloted questionnaire which contained open and specific questions. The questionnaire was given to all participants at the end of each videoconference. Answers to the specific questions were graded using the Likert scale. RESULTS: 40 of the 41 videoconferences were completed satisfactorily and were attended by 257 participants, all of whom completed questionnaires. However, no individual question was answered by all the participants. Of the responses 90% were positive on the topics of appropriateness of the teaching material for delivery by videoconference and of its educational level. 90% of responses also indicated a wish to attend further videoconferences and satisfaction at avoiding the need to travel to London for similar educational activity. 87% rated the lecturers as good or excellent in their use of the medium. 85% of responses indicated that the question and answer sessions within the videoconferences were useful and 82% that the visual aids enhanced the sessions. The technical aspects of the videoconferences were rated positively but to a lesser extent than the educational aspects with 69% of positive responses for visibility of visual aids, 54% for sound quality and 76% for the lecturers use of the technology. The technical aspects of the videoconferences improved during the pilot study. In response to the open questions, participants stated that they found the most useful aspects of the videoconferences were not having to travel, access to first rate lecturers, the discussions and the opportunity to interact with experts. CONCLUSIONS: The participants in this pilot study were positive about the use of videoconferencing to deliver educational material from dental schools to small groups. Once the technology has improved, this medium has the potential to provide CPE for dentists at work or at home in response to their specific needs.