Biomedical subjects
E W Odell
Publications and source records attributed to E W Odell.
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.
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.
A study of videoconferencing for postgraduate continuing education in dentistry in the UK--the teachers' view.
Videoconferencing is an established method for providing medical education over long distances. Our aims were to assess the feasibility of videoconferencing in dental postgraduate education, to evaluate its practicability, teacher satisfaction and evaluate equipment. Twenty-seven teachers from the 4 London Dental Schools provided 41 postgraduate dental education sessions on a range of topics to regional postgraduate centres and dental practices as part of the Thames Health Region's programme. Videoconferencing was carried out using a relatively inexpensive personal computer system link using ISDN2 telephone lines and Z350 protocol. Presenter views and assessment were obtained by questionnaire, interview and videotape. Teachers felt that minimal additional preparation time was required for videoconferencing and 21/27 preferred it to in-person teaching, most noting the saving in travel time. Only 3 of the teachers were dissatisfied with their ability to communicate, 4 were equivocal and 20 were either pleased or very pleased. The teachers largely enjoyed the experience and performed well in the new medium. However, sound quality proved inadequate in 5/41 links and most sessions included some periods of suboptimal sound. Only 4 teachers were satisfied with their ability to perform question and answer interaction with the audience. We conclude that experienced teachers adapt readily to videoconferencing and learn to communicate effectively very quickly. Teachers were positive about the medium despite its shortcomings and improvements in sound quality would allow a rapid expansion of postgraduate dental education by videoconference.
Cystic and glial mixed hamartoma of the tongue.
Choristomas and mixed hamartomas of the oral cavity are uncommon lesions that show a variety of clinical presentations, histological appearances and growth patterns. We report a case of an unusual mixed hamartoma of the posterior tongue composed of dermoid cyst, sebaceous and glial elements. Magnetic resonance imaging indicated a predominantly cystic lesion limited to the pharyngeal and posterior part of the anterior tongue. A conservative approach was adopted and the lesion has shown minimal growth for 2 years following diagnosis.
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.
Characterization of CD44 splicing patterns in normal keratinocytes, dysplastic and squamous carcinoma cell lines.
The CD44 glycoprotein is spliced from a complex gene of 10 constitutive and 10 variant exons. In this study, CD44 splicing patterns and intron 9 retention were investigated by exon-specific RT-PCR for variant exons v1-v10 and intron 9 in normal, immortalized, dysplastic and malignant keratinocytes. Expression of product was determined immunohistochemically for some of the exons. Normal keratinocytes showed one major transcript including exons v2-v10 and 3 minor transcripts. No lines showed a normal CD44 splicing pattern but rather a variety of truncated transcripts of contiguous variant exons which overall correlated with expression. Squamous cell carcinoma (SCC)-4 and SCC-9 lines showed relatively normal transcripts although protein was expressed only by SCC-9. SCC-12B2, SCC-15, SCC-25 and SCC-27 showed a series of shorter overlapping transcripts, with loss of exons v8-v10 in the major transcripts. Intron 9 was not retained in normal keratinocytes or cell lines. Despite the fact that keratinocytes constitutively express all variant exons, splicing patterns are distinctly abnormal and merit investigation as potential markers for epidermal and oral squamous malignancy.
Expression of E-cadherin, cellular differentiation and polarity in epithelial salivary neoplasms.
To investigate whether expression of E-cadherin correlates with polarised tissue organisation, grade or tumour type in salivary neoplasms, frozen sections from 30 salivary gland neoplasms were stained immunohistochemically for E-cadherin using the antibody HECD-1 and compared to the staining patterns in five samples of normal salivary gland. Lesions with areas of lack of staining were restained at two higher antibody concentrations. Normal salivary gland stained strongly around the periphery of acinar and ductal cells. Neoplasms mostly stained strongly regardless of neoplasm type. Reproducible loss of expression was found only in epithelial cells showing stromal or plasmacytoid (hyaline) differentiation in pleomorphic adenoma. Low- and high- grade mucoepidermoid carcinomas, adenocarcinoma NOS and carcinoma ex pleomorphic adenoma showed focal loss of expression but this was not related to tissue architecture, differentiation or invasiveness. We conclude that the relationship seen between E-cadherin expression and cell polarity/glandular organisation in breast and colon does not appear to exist for salivary gland neoplasms in which the diversity of architectural patterns precludes detection of any simple relationship. E-cadherin expression seems unlikely to be a useful marker for diagnosis or prognosis in salivary neoplasia in general.
Plasma concentrations of reputed tumor-associated soluble CD44 isoforms (v5 and v6) in smokers are dose related and decline on smoking cessation.
There is some evidence to suggest that smoking may affect circulating levels of CD44 (sCD44) molecules. Therefore, we investigated the effect of smoking on the circulating level of sCD44 by comparing the change in total sCD44, sCD44v5, and sCD44v6 concentrations over 1 year in a group of people who quit smoking (n = 30) and a control group of people who continued to smoke (n = 30). Smoking status and compliance were monitored by analysis of plasma cotinine and expired CO levels and also by self-reported tobacco use. We show a dose-dependent relationship between smoke intake and baseline plasma concentrations of reputed tumor-associated CD44 variant isoforms (sCD44v5 and sCD44v6) in smokers (n = 60). There was a significant decline in the level of both sCD44v5 and sCD44v6 in quitters as compared with continuing smokers [-13.2 (95% confidence interval, -7.6 to -18.8; P < 0.001) and -62.2 ng/ml (95% confidence interval, -33.9 to -90.6; P < 0.001), respectively], but not in the total sCD44 concentration. These results show that the increased concentrations of sCD44v5 and sCD44v6 in smokers are dose related and reversible and suggest that the attributed diagnostic specificity and prognostic value of sCD44 molecules in malignant and inflammatory disease may be affected by smoking status.
Quantitative assessment of apoptosis in oral lichen planus.
OBJECTIVE: The aims of this study were to examine the frequency of apoptoses in oral lichen planus by in situ end labeling, to ascertain whether this technique is as sensitive as conventional histologic analysis, and to examine the effect of lymphocytic infiltration. STUDY DESIGN: Numbers of apoptoses in hematoxylin-eosin stained sections were compared with numbers of apoptotic nuclei identified by in situ end labeling in oral lichen planus (n = 26) and normal buccal epithelium (n = 8). Immunohistochemical staining with MIB-1 and for Bcl-2 and Bax enabled possible regulatory pathways to be investigated. RESULTS: In oral lichen planus, approximately 1 apoptotic cell was detected per millimeter of basal layer, cell death increasing with lymphocytic infiltration. Epithelial cell proliferation did not correlate with apoptosis. Bcl-2 expression was weak or absent in basal cells, and Bax was localized to upper prickle cells. CONCLUSIONS: Increased numbers of apoptoses were detected in oral lichen planus, especially in association with lymphocytic infiltration, higher numbers being seen with hematoxylin-eosin staining than with in situ end labeling.
Pyostomatitis vegetans associated with asymptomatic ulcerative colitis: a case report.
Pyostomatitis vegetans, a rare pustular disorder of the oral mucosa, is a highly specific marker for inflammatory bowel disease and may be difficult to treat. A case of pyostomatitis vegetans in a patient with long-standing asymptomatic ulcerative colitis is presented. Complete remission was achieved with topical steroids; no systemic treatment was required.
A case of metastasizing pleomorphic adenoma.
The pleomorphic adenoma is the most common benign salivary neoplasm. A case is presented in which a palatal pleomorphic adenoma seeded a metastasis in the medullary cavity of the anterior maxilla, apparently by hematogenous spread after surgical manipulation.