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Oral Leukoplakia (oral + leukoplakia)
Selected AbstractsThe oral health consequences of chewing areca nutADDICTION BIOLOGY, Issue 1 2002C. R. Trivedy Its effects on dental caries and periodontal tissues, two major oral diseases, are less well researched. Areca-induced lichenoid lesions mainly on buccal mucosa or tongue are reported at quid retained sites. In chronic chewers a condition known as betel chewer's mucosa, a discoloured areca nut-encrusted change, is often found where the quid particles are retained. Areca nut chewing is implicated in oral leukoplakia and submucous fibrosis, both of which are potentially malignant in the oral cavity. Oral cancer often arises from such precancerous changes in Asian populations. In 1985 the International Agency for Research on Cancer concluded that there is limited evidence to conclude that areca chewing may directly lead to oral cancer. There is, however, new information linking oral cancer to pan chewing without tobacco, suggesting a strong cancer risk associated with this habit. Public health measures to quit areca use are recommended to control disabling conditions such as submucous fibrosis and oral cancer among Asian populations. [source] Clinicopathological features and immunohistochemical expression of p53, Ki-67, Mcm-2 and Mcm-5 in proliferative verrucous leukoplakiaJOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 6 2010Adriele Ferreira Gouvêa J Oral Pathol Med (2010) 39: 447,452 Background:, Proliferative verrucous leukoplakia (PVL) is a distinct and aggressive type of oral leukoplakia which affects elderly women without risk behavior and presents high rates of malignant transformation. The objective of the present study was to evaluate the clinicopathological characteristics and the distribution of cell proliferation markers, aiming to elucidate the distinct biological behavior of the PVL. Methods:, Clinical and microscopical features of 12 patients with PVL were reviewed. Immunohistochemical analysis for p53, Ki-67, Mcm-2 and Mcm-5 were performed and the data were correlated. Results:, All patients were women, above 50 years of age, 91.7% were non-smoker and 100% were non-habitual drinker. Alveolar ridge (66.6%), tongue (50%) and buccal mucosa (41.6%) were the most affected sites. Four patients developed squamous cell carcinoma (SCC). The immunohistochemical findings showed higher positivity for p53, Ki-67, Mcm-2 and Mcm-5 in SCCs. However, some patients with mild or moderate dysplasia, specially the patients who developed SCC, presented high expression of Mcm-2 and Mcm-5. Conclusions:, High immunoexpression of Mcm-2 and Mcm-5 in mild and moderate dysplasia could be helpful to predict the malignant transformation of PVL. [source] Variant haplotypes at XRCC1 and risk of oral leukoplakia in HPV non-infected samplesJOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 2 2009Mousumi Majumder Background:, One of the mechanisms in human papillomavirus (HPV)-related carcinogenesis is inhibition of DNA repair by HPV oncoprotein. In this study, we investigated whether polymorphisms at XRCC1, one of the DNA repair loci, could modulate the risk of tobacco-related leukoplakia and cancer in HPV-infected individuals. Methods:, Tissue DNA from 83 oral cancer, 91 leukoplakia and 100 healthy controls were screened for HPV 16/18 infection and polymorphisms at XRCC1 by PCR,RFLP to estimate the risk of diseases independently and jointly. Results:, Human papillomavirus infection was significantly associated with increased risk of leukoplakia and cancer (OR = 2.8, 95% CI = 1.2,6.5 and OR = 5.5, 95% CI = 1.6,19, respectively). Independently, genotypes at three polymorphic sites on XRCC1 did not modulate the risk of diseases but pooled variant haplotypes increased the risk of leukoplakia in overall and HPV non-infected (OR = 1.8, 95% CI = 1.2,2.8; OR = 2.2, 95% CI = 1.2,4.0, respectively) samples but not that of cancer. Conclusion:, The association between variant haplotypes at XRCC1 and risk of leukoplakia is pronounced in non-infected individuals since HPV oncoprotein could inhibit directly the DNA repair activity of XRCC1. But more samples of leukoplakia and cancer are essential to validate these results. [source] Patients with oral cancer developing from pre-existing oral leukoplakia: do they do better than those with de novo oral cancer?JOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 3 2008Manon Weijers Background:, It has been suggested that patients with squamous cell carcinomas derived from oral leukoplakia have a better prognosis than patients with carcinomas that are not associated with oral leukoplakia. Aim:, To study the mortality rate of 19 patients with a squamous cell carcinoma derived from pre-existing oral leukoplakia. Method:, The mortality rate of 19 patients with a proven oral squamous cell carcinoma derived from a pre-existing oral leukoplakia was compared with that of a similar size group of patients with oral carcinoma without a pre-existing oral leukoplakia, being matched for gender, age, smoking habits, use of alcohol, oral subsite and histopathologic grade. Treatment in all patients was primarily by surgical excision. The mortality rates up to 5 years have been computed according to the Kaplan,Meier method. Result:, No significant difference of the mortality rates up to 5 years of follow-up was observed between the two groups of patients. Conclusion:, Patients with oral cancer developing from pre-existing oral leukoplakia do not do better than those with de novo oral cancer. [source] Prevalence of oral cancer and pre-cancer and associated risk factors among tea estate workers in the central Sri LankaJOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 10 2007A. Ariyawardana Background:, To screen for oral cancer or not is being debated, but for high-risk populations with minimal access to regular dental care systematic oral examinations could provide some benefit. Methods:, We undertook oral mucosal examinations of labourers employed in tea estate plantations in Sri Lanka. In a two-stage screening procedure, first by estate medical officers and then by visiting specialists, we examined 12 716 persons at their workplaces achieving a coverage of one-sixth of the total workforce. Results:, Fourteen oral cancers and 848 subjects with oral pre-cancer (6.7%) were detected giving population prevalences of 46.1 per 1000 for leukoplakia and 16.4 per 1000 for oral submucous fibrosis. Among subjects with any oral mucosal disorder (n = 1159) proportions of current users of betel quid, smokers and alcohol use was recorded at 92%, 31% and 61% respectively. The synergistic effect of these three risk habits on the development of oral leukoplakia was evident in mixed habit groups. Conclusions:, The prevalence of oral pre-cancer in tea estate labourers was higher than estimates reported in previous studies. In the absence of state-sponsored preventive activities, it is necessary to improve the capacity of individual health practitioners and small medical centres to participate in oral health promotion and oral cancer/pre-cancer screening. [source] A long-term follow-up study on the natural course of oral leukoplakia in a Swedish population-based sampleJOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 2 2007A. Roosaar Aim:, To assess the natural course of screening-detected oral leukoplakia (OL) among non-consulting individuals. Methods:, A cohort of 555 individuals with OL, confirmed in 1973,1974 during a population-based survey, were followed through January 2002 via record linkages with nationwide and essentially complete registers. A sample of 104 drawn from the 297 surviving cohort members who still were living in the area in 1993,1995 was invited to a re-examination. Sixty-seven of them attended. Results:, At the time of re-examination OL had disappeared in 29 (43%) individuals. There was a statistically significant association between cessation of/no smoking habits in 1993,1995 and the disappearance of OL. Never/previous daily smokers were thus over-represented among individuals whose OL had disappeared compared to those with persisting OL [n = 23 (82%) vs. n = 18 (47%), P < 0.01]. Eighteen (78%) of the twenty three non-smokers with disappearing OL had quit after the initial examination. One man and two women developed oral cancer during follow-up while 0.7 and 0.07, respectively, were expected. Conclusion:, Smoking cessation was associated with an increased disappearance of OL. Hence, at least one-fourth had lesions that could be classified as tobacco-related. Small observed and expected numbers prohibited firm conclusions about a possible excess risk of developing oral cancer. [source] Immunohistochemical study of syndecan-1 down-regulation and the expression of p53 protein or Ki-67 antigen in oral leukoplakia with or without epithelial dysplasiaJOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 9 2003Hideo Kurokawa Abstract Background:, Leukoplakia is an oral pre-cancerous lesion that sometimes develops into squamous cell carcinoma. Therefore, leukoplakia with epithelial dysplasia is useful for studying carcinogenesis at the cellular level. The purpose of this study was to evaluate a potential association between the loss of syndecan-1 expression and the expression of p53 protein and Ki-67 antigen, and to identify reliable markers for predicting malignant changes in oral leukoplakia with epithelial dysplasia. Methods:, Changes in the expression of syndecan-1, p53, and Ki-67 were examined immunohistochemically in 43 cases of oral leukoplakia with or without epithelial dysplasia. The subjects were categorized as: none, 13 cases; mild dysplasia, 5 cases; moderate dysplasia, 17 cases; and severe dysplasia, 8 cases. The expression of these molecules in normal oral epithelia (22 cases) was also investigated. Results:, Strong syndecan-1 expression was observed on the surface of keratinocytes in normal epithelium. Immunopositivity was lost gradually as the extent of epithelial dysplasia increased. In normal epithelium, p53 and Ki-67 appeared mainly in the basal cell layer, while they were more widely distributed in leukoplakia. Specifically, significant changes were observed in the labeling index of p53 and Ki-67 in leukoplakia as epithelial dysplasia progressed from mild to moderate or severe. Conclusion:, Our results reveal that overexpression of p53 protein and Ki-67 antigen, and down-regulation of syndecan-1 expression in the lower part of the epithelium, are associated with dysplastic changes. Therefore, the down-regulation of syndecan-1 expression may be the most important reliable marker for dysplastic changes. [source] Loss of heterozygosity at APC and MCC genes of oral cancer and leukoplakia tissues from Indian tobacco chewersJOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 8 2003Nilabja Sikdar Abstract Background:, Loss of heterozygosity (LOH) at tumor suppressor genes, such as adenomatous polyposis coli (APC) and mutated in colon cancer (MCC) genes, is one of the early events in carcinogenesis of oral tissue in Caucasian and Chinese patients. We wanted to check whether it is also true in Indian oral pre-cancer and cancer patients. Methods:, Loss of heterozygosity at APC and MCC genes was investigated in 57 and 40 unrelated primary oral leukoplakia (a pre-cancerous lesion) and squamous cell carcinomas (SCC), respectively, by polymerase chain reaction. Results:, In these samples, most of the leukoplakia patients had tobacco smoking habit whereas majority of cancer patients had tobacco chewing habit. LOH at APC gene was observed in 4 of 16 (25%) and 1 of 29 (3%) informative tumor and leukoplakia DNAs from tobacco chewers, respectively. LOH at MCC gene was not detected either in tumor or in leukoplakia DNAs. Conclusion:, This infrequent LOH at APC gene of pre-cancer and cancer tissues suggests that it may not be an early event in oral carcinogenesis in these patients. [source] Oral pre-cancer and the associated risk factors among industrial workers in Japan's overseas enterprises in the UKJOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 5 2003Toru Nagao Abstract Background: ,Screening at industries has been advocated as a method of early detection for cancer. This study describes the prevalence of oral pre-cancerous lesions and other mucosal diseases following oral mucosal screening, and associated risk factors among Japanese industrial workers in the UK. Methods: ,Oral mucosal screening was by invitation at 51 industrial locations in the UK. A self-administered questionnaire was used to record socio-behavioural factors and frequency of daily intake of fruits and vegetables. Results: ,Four hundred and eighty-four subjects attended for oral mucosal screening (mean age 39.9 ± 8.3 years) and their mean period of residence in UK was 5.3 ± 4.5 years. 63.4% examined were male. 31.3% of males and 26.6% of females smoked daily. The gender differences were striking compared with Japan's national rates. A higher proportion of managerial staff was regular heavy (20+ per day) smokers. The intake of more than five portions per day of vegetables and/or fruits during the weekend was significantly higher in females than in males (P = 0.022). One hundred and six subjects (22%) were detected with oral mucosal lesions, including 16 leukoplakia lesions (3.3%) and three with oral lichen planus (1%). The rate of positive detections was higher in managers (7.5%). Odds ratios were estimated by socio-behavioural variables. Among subjects positive for oral leukoplakia, managers accounted for 68.8% (OR 5.26; 95% CI, 1.24,22.29). 87.5% of subjects detected with oral leukoplakia smoked daily and had done so for the past 10 years (OR 28.40; 95% CI, 5.63,143.28). Though regular alcohol drinking was a common feature among male leukoplakia cases, heavy alcohol misuse was not encountered. None reported an intake of five or more portions of fruits or vegetables. Conclusions: ,The Japanese nationals working in managerial positions in the UK and daily regular smokers in the industries visited were found to be at a high risk of oral pre-cancer. Regular dental/oral check up and tobacco education programmes are encouraged for oral cancer/pre-cancer control in industrial settings. [source] AgNOR count as objective marker for dysplastic features in oral leukoplakiaJOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 9 2002Amit Chattopadhyay Abstract Background:,, Dysplasia is an important feature of leukoplakia. Because agreement among oral pathologists is poor regarding lesional diagnosis, silver stainable nucleolar organizer regions (AgNORs) as replicatory markers may have a place in objectively characterizing dysplasia in tissue specimens. Methods:,, We studied 41 normal oral epithelia, 51 oral leukoplakia (26 dysplastic, 25 non-dysplastic), and 51 cases of squamous cell carcinoma specimens for their mean AgNOR counts. Results:,, Mean AgNOR counts increased gradually from normal epithelium to non-dysplastic to dysplastic leukoplakia to squamous cell carcinoma. Using ROC analysis, we determined a mean AgNOR count cut-point (2.37) that can be used to distinguish between dysplastic and non-dysplastic leukoplakia. The test had a sensitivity of 75% and specificity of 83% with area under the curve being 88%. Conclusions:, Mean AgNOR count could be a valuable criterion for defining objective parameters for diagnosis/determination of dysplasia distinguishing between dysplastic and non-dysplastic leukoplakia. [source] Effective management of smoking in an oral dysplasia clinic in LondonORAL DISEASES, Issue 1 2006TWJ Poate Background:, Precancerous lesions precede the development of oral cancer; of several clinical types the most common is leukoplakia. The risk factors include tobacco and excess alcohol use and diets low in antioxidants. Studies concerning the management of risk factors related to oral precancer are meager. Objectives:, We investigated the effectiveness of smoking cessation at a dysplasia clinic among patients followed up for at least for 12 months. Methods:, Data from case notes relating to180 patients with white and red patches of oral mucosa (excluding other benign disorders confirmed by biopsy findings) attending a dysplasia clinic at a teaching hospital in London and seen by one consultant between 1993 and 2003 were transcribed. Effect of referring to a smoker's clinic to receive specialist help was evaluated against brief advice given at the dysplasia clinic ± medications. Results:, The mean age at the first visit was 48.5 years (±12.5), 65% were male, and 88% were white European. One hundred and sixty-two patients (90%) had used tobacco and 83% were current smokers. Of the smokers 95% had smoked over 10 years, the majority smoking over 10 cigarettes per day. Nine were alcohol misusers including two binge drinkers. One hundred and forty-six were diagnosed with oral leukoplakia, 16 with non-homogeneous types (speckled or nodular). Three patients were diagnosed with an erythroplakia. Nineteen per cent exhibited the presence of dysplasia and one subject had in situ carcinoma. Five patients in the sample quit smoking prior to arrival in the dysplasia clinic. Twenty-seven cases (20%) with oral leukoplakia quit smoking while registered as a patient at the dysplasia clinic: 17 of 100 subjects quit with brief advice ± medications and 10 of 30 following referral to the smoker's clinic. The difference between the two groups was significant for point prevalence abstinence at the last visit to the clinic (minimum 12 months follow up). Out of a total of 180 precancer cases managed in the dysplasia clinic (mean follow up 4.2 years) three patients subsequently developed invasive carcinoma during follow up. Conclusions:, Smoking cessation needs to be an integral component of management of cases attending a dysplasia clinic and referring to smoker's clinics could help to improve the effectiveness of managing patients with oral precancer to quit smoking. [source] S-phase fraction and DNA ploidy in oral leukoplakiaANZ JOURNAL OF SURGERY, Issue 7-8 2010Rahul Khanna Abstract Background:, The risk of malignant conversion in oral leukoplakia is well documented. Histological findings are often unreliable and it is difficult to predict on the basis of clinical and histopathological changes which leukoplakic lesion will turn malignant. Methods:, We used the technique of flow cytometry to evaluate the ploidy status, DNA index and S-phase fraction in leukoplakia, oral cancer and normal oral mucosal biopsies and compared it with histological findings. The study was carried out on 30 patients with oral cancer, 60 with leukoplakia and 30 with normal oral mucosal biopsies. Results:, The aneuploidy rate in oral cancers was 64%, for leukoplakia 20%, while all normal mucosal biopsies were diploid. Aneuploid lesions also had a greater S-phase fraction (SPF). The DNA Index (DI) of aneuploid oral cancers was 1.72 and aneuploid leukoplakias was 1.24. Leukoplakia specimens which showed histological evidence of dysplasia had aneuploidy rate of 38%, DI of 1.19 and SPF of 6.2%. The corresponding values for leukoplakia specimens without dysplasia were 14%, 1.09 and 4.1%, respectively. Conclusion:, The method of flow cytometry can be used to identify the subset of leukoplakia patients who are at a higher risk of malignant conversion. These patients could undergo more rigid surveillance or undergo excision biopsy of their lesions. [source] Human papillomavirus as a risk factor in oral carcinogenesis: a study using in situ hybridization with signal amplificationMOLECULAR ORAL MICROBIOLOGY, Issue 4 2008R. Acay Introduction:, It is still controversial whether human papillomavirus (HPV) can be considered a risk factor in oral carcinogenesis. The aim of this study was to detect HPV DNA in 50 cases diagnosed as oral leukoplakias, with different degrees of epithelial dysplasia, and as oral squamous cell carcinomas, using in situ hybridization with signal amplification (CSA-ISH). Methods:, HPV DNA was assessed in paraffin sections using CSA-ISH with a wide-spectrum biotinylated DNA probe. In HPV-positive cases, genotyping with specific probes to HPV types 6/11, 16/18 and 31/33 was performed. Results:, The overall prevalence of HPV infection was 24%, markedly higher than that found in the control group. Results showed a discrete proportional relationship in the indices found in leukoplakia with no dysplasia, leukoplakia with dysplasia, and squamous cell carcinoma, but this was not statistically significant. When separating the group of leukoplakia by degrees of dysplasia, this relation of proportion was not observed. In genotyping, HPV types 16/18 were the most prevalent, and types 6/11 were only found in groups of mild or no dysplasia. Conclusion:, The results suggest that HPV is not likely to play a role in the progression of malignant transformation in oral lesions. Nevertheless, the increased prevalence of HPV infection compared to normal oral mucosa and the fact that high-risk HPV types were the most frequently identified do not allow the exclusion of HPV as a risk factor in oral carcinogenesis. [source] | ||||||||||