Cancerisation within the oral cavity: the use of 'field mapping biopsies' in clinical management

Management of Oral Potentially Malignant Disorders

Patients with oral potentially malignant disorders (OPMDs), including oral leukoplakia and erythroplakia, proliferative verrucous leukoplakia, oral submucous fibrosis, and oral lichen planus/lichenoid lesions can be challenging to manage. A small proportion will undergo cancer development and determining a patient's cancer risk is key to making management decisions. Yet, our understanding of the natural history of OPMDs has not been fully elucidated, and a precision approach based on the integration of numerous predictive markers has not been validated by prospective studies. Evidence-based health promotion by clinicians and healthcare systems is not embraced universally. Medical and surgical interventions evaluated by rigorous research measuring important endpoints, such as cancer development, mortality, or survival are difficult and expensive to run. Most of these studies employ non-ideal surrogate endpoints and have deep methodologic flaws. Diagnostic criteria for enrolling research subjects are not uniform, and patients with the highest risk for cancer development comprise small proportions of those enrolled. Few studies explore quality of life and patient preferences. It is time to rethink how we approach the management of these patients, across each OPMD, and considering the healthcare infrastructure and cost effectiveness. Global networks with well-characterized patient populations with OPMDs and well-designed interventional trials using validated outcome measures are needed.

The "Peter Principle" revisited-Reflections on science, surgery and research

Revisiting the eponymous "Peter Principle," in this article the author reflects upon a professional lifetime as a clinician, surgeon and researcher, and summarises his efforts to improve contemporary understanding of oral cancer development, refine diagnostic procedure and facilitate efficacious, early treatment intervention to halt the process of carcinogenesis. The author reviews the principles underpinning effective translational research. Utilising his own work in oral epithelial cell science, interventional surgery and potentially malignant disorder patient management and surveillance, a number of significant advances in our knowledge base and their specific clinical application and potential impact are discussed. Research remains an active and ongoing process, however, and the author believes it essential for future relevance that hypotheses should always be initiated, led and mentored by experienced clinical practitioners.

Perspectives on oral squamous cell carcinoma prevention-proliferation, position, progression and prediction

Squamous cell carcinoma arising from oral mucosal epithelium remains a lethal and deforming disease due to tumour invasion, oro-facial destruction, cervical lymph node metastasis and ultimate blood-borne dissemination. Worldwide, 300 000 new cases are seen each year, with a recent and significant rise in incidence affecting particularly the young. To rationalize perspectives on preventive strategies in oral cancer management, this study addresses a number of fundamental questions regarding carcinogenesis: proliferation-what epithelial cell changes precede tumour development? Position-why are certain oral sites so predisposed to cancer? Progression-why do some precursor lesions progress to invasive carcinoma and others do not? Prediction-how can we predict individual patient and/or lesion behaviour to prevent disease progression? By improving our understanding of oral carcinogenesis, can we thereby facilitate more effective primary, secondary and tertiary preventive strategies and ultimately reduce the global burden of oral squamous cell carcinoma (OSCC)?

Diseases and Molecular Diagnostics: A Step Closer to Precision Medicine

The current advent of molecular technologies together with a multidisciplinary interplay of several fields led to the development of genomics, which concentrates on the detection of pathogenic events at the genome level. The structural and functional genomics approaches have now pinpointed the technical challenge in the exploration of disease-related genes and the recognition of their structural alterations or elucidation of gene function. Various promising technologies and diagnostic applications of structural genomics are currently preparing a large database of disease-genes, genetic alterations etc., by mutation scanning and DNA chip technology. Further the functional genomics also exploring the expression genetics (hybridization-, PCR- and sequence-based technologies), two-hybrid technology, next generation sequencing with Bioinformatics and computational biology. Advances in microarray “chip” technology as microarrays have allowed the parallel analysis of gene expression patterns of thousands of genes simultaneously. Sequence information collected from the genomes of many individuals is leading to the rapid discovery of single nucleotide polymorphisms or SNPs. Further advances of genetic engineering have also revolutionized immunoassay biotechnology via engineering of antibody-encoding genes and the phage display technology. The Biotechnology plays an important role in the development of diagnostic assays in response to an outbreak or critical disease response need. However, there is also need to pinpoint various obstacles and issues related to the commercialization and widespread dispersal of genetic knowledge derived from the exploitation of the biotechnology industry and the development and marketing of diagnostic services. Implementation of genetic criteria for patient selection and individual assessment of the risks and benefits of treatment emerges as a major challenge to the pharmaceutical industry. Thus this field is revolutionizing current era and further it may open new vistas in the field of disease management.

Second primary cancer after index head and neck squamous cell carcinoma in Northern China

OBJECTIVE

To evaluate the clinicopathologic features, prognostic factors, and management of patients in the North Chinese population with head and neck squamous cell carcinoma (HNSCC) who developed a second primary malignancy (SPM).

METHODS

This was a retrospective study including 1818 eligible patients between June 1999 and April 2011.

RESULTS

A total of 188 HNSCC patients developed SPM. Multiple oral dysplastic lesions (MODLs) (P < .001) were among the risk factors for occurrence of SPM. However, MODLs were closely associated with many mild pathologic features, such as early T stage (P < .001), early N stage (P = .036), good pathologic differentiation (P < .001), and mild growth pattern (P < .001). Interestingly, multivariate survival analysis showed that SPM patients had a better prognosis if they had the characteristics of MODLs (P = .020).

CONCLUSIONS

MODLs were a crucial risk factor leading to the occurrence of oral SPM after an index HNSCC in patients in Northern China. However, SPM patients with the characteristics of MODLs had a better prognosis.

Application of direct oral microscopy in evaluating mucosal margins around invasive oral squamous cell carcinoma

INTRODUCTION

Direct oral microscopy constitutes a novel, non-invasive diagnostic technique, which aids clinical examination of the oral cavity. The oral mucosa is examined at multiple magnifications and features such as sub-epithelial mucosal vessels, surface patterns, colour tone, transparency and the exact demarcation of mucosal lesions are estimated. The incidence of oral squamous cell carcinoma (OSCC) oscillates between 1.9% and 3.5%, which makes it the eighth most common carcinoma occurring around the world and in Poland. The 5-year survival rates oscillate between 20% and 30%.

AIM

The aim of the study was to evaluate clinically unchanged mucosal margins around OSCC by direct oral microscopy. The authors approached the question whether the borders of mucosal margins around OSCC established via direct oral microscopy differ from those established based on clinical examination.

MATERIAL AND METHODS

Fifteen patients diagnosed with OSCC were enrolled. Patients were first clinically examined to evaluate the extent of the tumour and to plan resection margins. Eventually, direct oral microscopy was performed to establish the width of the subclinically unchanged mucosal margins based on a standard picture of healthy oral mucosae, followed by comparison with those established by clinical evaluation.

RESULTS

Histopathologic results of biopsies from areas indicated by direct oral microscopy revealed dysplasia in 86.7% of patients, whereas biopsies from areas indicated by clinical examination revealed dysplasia only in 40% of individuals, resulting in the need for widening of mucosal margins.

CONCLUSIONS

Direct oral microscopy enables detection of dysplasia within clinically unaltered mucosal margins around OSCC, which results in more precise establishing of resection boundaries, contributing to improvement of resection totality.

Risk factors for patients with multiple synchronous primary cancers involving oral and oropharyngeal subsites

OBJECTIVE

To evaluate risk factors and prognosis for multiple synchronous primary cancers (MSPCs) associated with head and neck squamous cell carcinoma.

STUDY DESIGN

The retrospective study included 1623 patients.

RESULTS

The most common MSPC site involved was the head and neck region. The presence of multiple oral dysplastic lesions (P < .001) was the sole risk factor for the occurrence of MSPCs. A multivariate survival analysis showed that the pathologic grade (P = .003) was an independent predictive factor for the 5-year disease-specific survival of patients with MSPCs. A Kaplan-Meier analysis showed that the 5-year disease-specific survival of patients who developed MSPCs was worse than that of patients who did not develop MSPCs (P = .020).

CONCLUSIONS

MSPCs are a significant negative prognostic factor for patients with head and neck squamous cell carcinoma. However, a worse prognosis is predicted for patients with MSPCs with several features: a higher pathologic grade, a more aggressive growth pattern, male gender plus a tobacco or alcohol habit, and no multiple oral dysplastic lesions.

Managing oral potentially malignant disorders:A question of risk

The concept of an oral disease process that presents as a ‘potentially malignant state’ that is neither entirely benign nor frankly malignant is a difficult concept both for clinicians and their affected patients. While it is recognised that a range of oral mucosal conditions, now collectively termed ‘potentially malignant disorders’, harbour an increased risk of squamous carcinoma, we remain frustratingly unable in contemporary clinical practice to predict individual lesion behaviour, quantify the risk of malignant transformation or objectively plan interventions.

Multiple Second Primary Oral Squamous Cell Carcinomas in a Nonsmoker and Nondrinker Woman: Case Report and Review of the Literature

AIM

This manuscript aims to describe an unusual case of multiple second primary squamous cell carcinomas (SCCs) in several sites of the oral mucosa in a nonsmoker and nondrinker woman and to discuss the diagnostic criteria, clinicopathological aspects and outcome of second primary tumor (SPT).

BACKGROUND

Patients treated for SCC of the head and neck are at high risk for developing SPT arising from the same dysplastic mucosal feld. Currently, there is no reliable method to predict which of the patients will develop SPT.

CASE DESCRIPTION

A 64-year-old nonsmoker and nondrinker woman developed several second primary oral SCCs in 7 years of follow-up, most of them being synchronic, treated by surgery without and with chemotherapy and radiotherapy.

CONCLUSION

Patients treated for SCC require a long-term and careful follow-up as the development of SPT contributes with significantly negative impact on the prognosis.

CLINICAL SIGNIFICANCE

This report describes the diagnosis and management of a very unusual case of several SPTs affecting different sites of the oral mucosa in the same patient. Moreover, the patient had no apparent risk factors associated with the development of the oral cancer. Therefore, a brief update concerning SPT and its diagnosis and management is also provided.

The role of interventional surgery in oral potentially malignant disorders

Oral potentially malignant disorders are mucosal diseases with a significantly increased risk of squamous carcinoma development – a lethal and deforming disease with rising incidence, especially in young people. Despite the ability to recognise pre-cancer disorders in patients, clinicians remain unable to predict individual mucosal lesion behaviour or quantify the risk of malignant transformation. No clear management guidelines exist and the available scientific literature is unable to answer the fundamental question: does early diagnosis and interventional management treat pre-cancer effectively and prevent malignant transformation?

Between-lesion discrepancies in terms of dysplasia, cell turnover and diagnosis in patients with multiple potentially malignant oral lesions

Objective:

The present study assessed patients with multiple oral lesions to evaluate the mis-estimation rate in terms of diagnosis and risk of malignant transformation when only one biopsy is performed.

Study Design:

Thirty-five patients presenting at least two white and/or red lesions in different oral mucosa sites with a final diagnosis of leuko/erythroplakias or lichenoid lesions were included, for a total of 70 biopsies.

Results:

Nineteen patients (54%) had at least one between-lesion discrepancy considering the presence/absence of dysplasia (10 patients), normal/high cell turnover (13 patients) or diagnosis (5 patients). Discrepancies were not related to clinical aspect or within-patient similarity of lesions.

Conclusions:

Multiple oral lesions in the same patient can significantly differ in terms of dysplasia, high cell turnover and, even diagnosis. Multiple biopsies are imperative and diagnosis as well as risk of malignant transformation should be formulated for each single lesion rather than for each individual patient.

Oral field cancerization: current evidence and future perspectives

INTRODUCTION

Oral field cancerization implies that oral cancer does not arise as an isolated cellular phenomenon but rather as an anaplastic tendency involving many cells at once and results in the multifocal development of cancer at various rates within the entire field in response to a carcinogen especially tobacco. This concept has been frequently used to explain the occurrence of multiple primary cancers and recurrences following complete excision of oral cancer.

DISCUSSION

This review deals in detail with the origin, principle, various theories used to explain this effect and molecular, genetic, as well as cytogenetic findings related to oral field cancerization. Further, the clinical implications and future research directives are also discussed.

Factors related to late stage diagnosis of oral squamous cell carcinoma

AIMS

To identify factors related to advanced-stage diagnosis of oral cancer to disclose high-risk groups and facilitate early detection strategies.

STUDY DESIGN

An ambispective cohort study on 88 consecutive patients treated from January 1998 to December 2003.

INCLUSION CRITERIA

pathological diagnosis of OSCC (primary tumour) at any oral site and suffering from a tumour at any TNM stage. Variables considered: age, gender, smoking history, alcohol usage, tumour site, macroscopic pattern of the lesion, co-existing precancerous lesion, degree of differentiation, diagnostic delay and TNM stage.

RESULTS

A total of 88 patients (mean age 60±11.3; 65.9% males) entered the study. Most patients (54.5%) suffered no delayed diagnosis and 45.5% of the carcinomas were diagnosed at early stages (I-II). The most frequent clinical lesions were ulcers (70.5%). Most cases were well- and moderately-differentiated (91%). Univariate analyses revealed strong associations between advanced stages and moderate-poor differentiation (OR=4.2; 95%CI=1.6-10.9) or tumour site (floor of the mouth (OR=3.6; 95%CI=1.2-11.1); gingivae (OR=8.8; 95%CI=2.0-38.2); and retromolar trigone (OR=8.8; 95%CI=1.5-49.1)). Regression analysis recognised the site of the tumour and the degree of differentiation as significantly associated to high risk of late-stage diagnosis.

CONCLUSIONS

Screening programmes designed to detect asymptomatic oral cancers should be prioritized. Educational interventions on the population and on the professionals should include a sound knowledge of the disease presentation, specifically on sites like floor of the mouth, gingivae and retromolar trigone. More studies are needed in order to analyse the part of tumour biology on the extension of the disease at the time of diagnosis.

Predictors for tumor recurrence after primary definitive surgery for oral cancer

PURPOSE

The purpose of this study was to identify significant predictors for oral squamous cell carcinoma recurrence.

PATIENTS AND METHODS

This Ambispective cohort study was performed in consecutive metastasis-free patients treated for oral squamous cell carcinoma with curative intent from 1998 through 2003. Variables included gender, age, tumor site, macroscopic pattern of the lesion, coexisting disorders (diabetes, hepatic and heart disorders, other tumors/diseases), degree of differentiation, and pathologic TNM stage. Tumor recurrence was considered the dependent variable (outcome). The distribution of recurrences was assessed with χ(2) test. Survival times were estimated by Kaplan-Meier curves and differences were examined with log-rank test. Multiple Cox regression study was also performed. The significance level chosen for all tests was P < .05.

RESULTS

One hundred eighteen patients entered the study. Tumor recurrence was 44.9% during the follow-up period (10% local, 29.7% regional, and 5% distant). The mean period that had elapsed before recurrence was 15 months (1.5 to 81.8), with most recurrences (66%) during the first year after treatment (84.9% before 2 years). Multivariate Cox regression analysis indicated the presence of a coexisting disorder (P = .022) as the most relevant prognostic factor for relapse, because patients with associated diseases had a 2.43-fold risk of recurrence. Tumor stage (P = .037), degree of differentiation (P = .042), and macroscopic pattern of the lesion (P = .022) were also identified as prognostic factors for relapse.

CONCLUSIONS

The risk profile for oral cancer recurrence includes patients younger than 60 years with coexisting diseases whose primary tumor occurred as an ulcerated lesion, and diagnosed at an advanced stage with a poorly differentiated tumor.

Prospective evaluation of outcome after transoral CO(2) laser resection of T1/T2 oral squamous cell carcinoma

OBJECTIVE

Oral cancer is the sixth most common cancer in the world. The incidence of oral squamous cell carcinoma (OSCC) continues to be high, if not increasing. This prospective study assessed the oncological outcomes following transoral CO(2) laser resection of T1/T2 N0 OSCC. Patients' 3-year disease-specific survival and disease-free survival were evaluated.

MATERIAL AND METHODS

The patients' data included a range of clinical, operative, and histopathological variables related to the status of the surgical margins. Data collection also included recurrence, cause of death, date of death, and last clinic review. Ninety patients (64 males and 26 females) participated in this study. Their mean age at the first diagnosis of OSCC was 63.5 years. Two thirds of the patients were Caucasians. Usually patients present with an ulcer of the tongue, floor of mouth, or buccal mucosa. Current and ex-smokers represented 82.2% of the cohort, whereas current and ex-drinkers were 78.9%. Comorbidities included history of oral lichen planus, oral submucous fibrosis, immunodeficiency, oral dysplasia, or OSCC. Clinically, 81 patients had T1N0 disease and 9 had T2N0 disease.

RESULTS

Pathologic analysis revealed that nearly half of the patients had moderately differentiated OSCC, 18 moderately to poorly differentiated, and 19 poorly differentiated carcinoma. Study of the tumor margins was carried out and showed a mean of 5.7-mm depth of invasion; tumor clearance was primarily achieved in 73 patients. Recurrence was identified in 11 (12%) patients. The mean age of first diagnosis of the recurrence group was 76.4 years. The most common clinical presentation in the recurrence group was an ulcer involving the tongue or buccal mucosa; most commonly were identified in current or ex-smokers or drinkers. Recurrence was associated with clinical N-stage disease. The surgical margins in this group were also evaluated following relaser excision or surgical excision ± neck dissection. Follow-up resulted in a 3-year survival of 86.7%. Twelve patients died: 9 from noncancer-related causes, 2 from locoregional disease spread, and 1 from distant metastasis to the lungs.

CONCLUSIONS

Squamous cell carcinoma of the oral cavity has a poor overall prognosis with a high tendency to recur at the primary site and extend to involve the locoregional lymph nodes. The overall results of this study suggest that CO(2) laser is a comparable modality to other traditional interventions (surgery) in the management of low-risk (T1/T2) tumors of the oral cavity.

Clinicopathological parameters, recurrence, locoregional and distant metastasis in 115 T1-T2 oral squamous cell carcinoma patients

The incidence of oral squamous cell carcinoma remains high. Oral and oro-pharyngeal carcinomas are the sixth most common cancer in the world. Several clinicopathological parameters have been implicated in prognosis, recurrence and survival, following oral squamous cell carcinoma. In this retrospective analysis, clinicopathological parameters of 115 T1/T2 OSCC were studied and compared to recurrence and death from tumour-related causes.

The study protocol was approved by the Joint UCL/UCLH committees of the ethics for human research. The patients' data was entered onto proformas, which were validated and checked by interval sampling. The fields included a range of clinical, operative and histopathological variables related to the status of the surgical margins. Data collection also included recurrence, cause of death, date of death and last clinic review. Causes of death were collated in 4 categories (1) death from locoregional spread, (2) death from distant metastasis, (3) death from bronchopulmonary pneumonia, and (4) death from any non-tumour event that lead to cardiorespiratory failure.

The patients' population comprised 65 males and 50 females. Their mean age at the 1^st diagnosis of OSCC was 61.7 years. Two-thirds of the patients were Caucasians. Primary sites were mainly identified in the tongue, floor of mouth (FOM), buccal mucosa and alveolus. Most of the identified OSCCs were low-risk (T1N0 and T2N0). All patients underwent primary resection ± neck dissection and reconstruction when necessary. Twenty-two patients needed adjuvant radiotherapy. Pathological analysis revealed that half of the patients had moderately differentiated OSCC. pTNM slightly differed from the cTNM and showed that 70.4% of the patients had low-risk OSCC. Tumour clearance was ultimately achieved in 107 patients. Follow-up resulted in a 3-year survival of 74.8% and a 5-year survival of 72.2%.

Recurrence was identified in 23 males and 20 females. The mean age of 1^st diagnosis of the recurrence group was 59.53 years. Most common oral sites included the lateral border of tongue and floor of mouth. Recurrence was associated with clinical N-stage disease. The surgical margins in this group was evaluated and found that 17 had non-cohesive invasion, 30 had dysplasia at margin, 21 had vascular invasion, 9 had nerve invasion and 3 had bony invasion. Severe dysplasia was present in 37 patients. Tumour clearance was achieved in only 8 patients. The mean depth of tumour invasion in the recurrence group was 7.6 mm.

An interesting finding was that 5/11 patients who died of distant metastasis had their primary disease in the tongue. Nodal disease comparison showed that 8/10 patients who died of locoregional metastasis and 8/11 patients who died from distant metastasis had clinical nodal involvement. Comparing this to pathological nodal disease (pTNM) showed that 10/10 patients and 10/11 patients who died from locoregional and distant metastasis, respectively, had nodal disease. All patients who died from locoregional and distant metastasis were shown to have recurrence after the primary tumour resection.

Squamous cell carcinoma of the oral cavity has a poor overall prognosis with a high tendency to recur at the primary site and extend to involve the cervical lymph nodes. Several clinicopathological parameters can be employed to assess outcome, recurrence and overall survival.

MAGE-A as a novel approach in the diagnostic accuracy of oral squamous cell cancer: a case report

Background

The aim of this case report is to introduce the combined use of brush biopsy and measurement of MAGE-A expression in the diagnosis of oral squamous cell carcinoma (OSCC).

Case report

We report of a 49-year old male patient who was referred to our department with a persistent-suspicious looking leukoplakia. Brush biopsy and an incisional biopsy were performed following clinical diagnosis. Histopathological examination revealed no malignancy. Expression analysis of melanoma-associated antigens A (MAGE-A) using real time RT-PCR was applied to brush biopsy materials because of the high prevalence of MAGE-A determined previously in OSCC's. Results indicated significant MAGE-A3 and A4 expression pattern. Therefore, the lesion was excised completely and an early invasive carcinoma was identified.

Conclusion

These results emphasize the role of brush biopsy using a tumor marker with a high expression frequency combined with a high sensitive and high specific detection system in the early diagnosis of OSCC, particularly in widespread leukoplakias.

[Squamous cell carcinoma and potentially malignant disorders of the oral mucosa]

Squamous cell carcinoma is the most frequent malignant tumor of the oral mucosa. Various endogenous and exogenous factors promote its development. Therapy and prognosis depend mainly on tumor stage. Early detection is therefore of utmost importance. In most cases cancer develops from "leukoplakia". Both homogeneous leukoplakias as well as "erythroleukoplakias" should be biopsied. The"brush-biopsy", imaging techniques, molecular biologic or DNA tests are not reliable enough at present, often technically demanding and not applicable in daily practice. In extensive lesions "field cancerization" has to be considered. Further important precursor lesions are proliferative verrucous leukoplakia and erosive lichen planus. The management of oral precancerous lesions should be individually tailored: Low-grade dysplasia can be observed. If indicated, patients at risk should be biopsied in intervals. High-grade dysplasia ("carcinoma in situ") should be surgically removed.

Factors affecting carbon dioxide laser treatment for oral precancer: a patient cohort study

BACKGROUND

Although the benefits of CO(2) laser surgery in oral precancer management have been evaluated, little consideration has been given to the factors which may influence treatment outcome, especially amongst patients developing recurrence or malignant transformation.

STUDY DESIGN

Seventy eight patients (51 males, 27 females; mean age 57.8 years) undergoing CO(2) laser excision of single, new dysplastic oral precancer lesions (OPLs) were followed up for a minimum of 2 years and the influence of clinico-pathological parameters, socio-demographic factors and the presence or absence of residual dysplasia in excision margins upon clinical outcome were examined.

RESULTS

Seventy three percent of patients were smokers and 78% consumed alcohol regularly. The majority of lesions were leukoplakias arising in the floor of mouth and ventro-lateral tongue and moderate or severe dysplasia accounted for 86% of histopathological diagnoses. Patient follow up ranged from 24 to 119 months (mean 58 months). Sixty four percent of patients were disease free at most recent clinical follow up, whilst 32% developed local recurrent dysplasia or new site dysplasia with 4% developing oral squamous cell carcinoma (but at sites distinct from their initial OPL). Excision margins were clear in 55% of cases, but 19% showed mild, 21% moderate and 5% severe dysplasia on histopathological examination. No statistically significant associations were seen between patients' age, gender, lesion appearance, site of origin, histopathological grading, presence of dysplasia in resection margins, or alcohol consumption and clinical outcome. Smokers, however, were at significantly higher risk of dysplasia recurrence compared to ex-smokers or non-smokers (P = 0.04).

CONCLUSIONS

In the absence of agreed treatment protocols for OPLs, we recommend CO(2) laser surgery as an effective treatment modality offering precise lesion excision, full histopathological assessment, minimal post-operative morbidity and a 64% disease free clinical outcome. Regular patient follow up is encouraged due to the persistence of field cancerisation effects.

Recent advances in Oral Oncology 2007: epidemiology, aetiopathogenesis, diagnosis and prognostication

This paper provides a synopsis of the main papers on epidemiology, diagnosis and prognosis of oral and oropharyngeal squamous cell carcinoma (OSCC) and head and neck SCC (HNSCC) published in 2007 in Oral Oncology - an international interdisciplinary journal which publishes high quality original research, clinical trials and review articles, and all other scientific articles relating to the aetiopathogenesis, epidemiology, prevention, clinical features, diagnosis, treatment and management of patients with neoplasms in the head and neck, and orofacial disease in patients with malignant disease.

Potentially malignant disorders of the oral and oropharyngeal mucosa; terminology, classification and present concepts of management

In a recently held WHO workshop it has been recommended to abandon the distinction between potentially malignant lesions and potentially malignant conditions and to use the term potentially malignant disorders instead. Of these disorders, leukoplakia and erythroplakia are the most common ones. These diagnoses are still defined by exclusion of other known white or red lesions. In spite of tremendous progress in the field of molecular biology there is yet no single marker that reliably enables to predict malignant transformation in an individual patient. The general advice is to excise or laser any oral of oropharyngeal leukoplakia/erythroplakia, if feasible, irrespective of the presence or absence of dysplasia. Nevertheless, it is actually unknown whether such removal truly prevents the possible development of a squamous cell carcinoma. At present, oral lichen planus seems to be accepted in the literature as being a potentially malignant disorder, although the risk of malignant transformation is lower than in leukoplakia. There are no means to prevent such event. The efficacy of follow-up of oral lichen planus is questionable. Finally, brief attention has been paid to oral submucous fibrosis, actinic cheilitis, some inherited cancer syndromes and immunodeficiency in relation to cancer predisposition.

Fluorescence spectroscopy for the detection of tongue carcinoma--validation in an animal model

The efficacy of fluorescence spectroscopy to detect squamous cell carcinoma is evaluated in an animal model following laser excitation at 442 and 532 nm. Lesions are chemically induced with a topical DMBA application at the left lateral tongue of Golden Syrian hamsters. The animals are investigated every 2 weeks after the 4th week of induction until a total of 26 weeks. The right lateral tongue of each animal is considered as a control site (normal contralateral tissue) and the induced lesions are analyzed as a set of points covering the entire clinically detectable area. Based on fluorescence spectral differences, four indices are determined to discriminate normal and carcinoma tissues, based on intraspectral analysis. The spectral data are also analyzed using a multivariate data analysis and the results are compared with histology as the diagnostic gold standard. The best result achieved is for blue excitation using the KNN (K-nearest neighbor, a interspectral analysis) algorithm with a sensitivity of 95.7% and a specificity of 91.6%. These high indices indicate that fluorescence spectroscopy may constitute a fast noninvasive auxiliary tool for diagnostic of cancer within the oral cavity.