On the natural course of oral lichen lesions in a Swedish population-based sample

OBJECTIVES: The aim was to assess the natural course of oral lichen lesions (OLL) among unselected, non-consulting individuals. SUBJECTS AND METHODS: A cohort of 327 subjects with OLL, confirmed in 1973-1974 during a population-based survey in two Swedish municipalities, was followed through January 2002 via record linkages with nationwide and essentially complete registers. A sample of 80 drawn from the 194 surviving subjects who still resided in the area in 1993-1995 was invited for interview and oral re-examination. RESULTS: At the end of follow-up, one case of oral cancer was detected, while 0.4 were expected. The overall mortality among subjects with OLL was not significantly different from that in the 15,817 OLL-free subjects who participated in the initial population based survey in 1973-1974. The lesion had disappeared in 14 (39%) of 36 re-examined subjects with white OLLs in 1973-1974, and four (11%) had transformed into red types. In the corresponding group of 19 with red forms initially, five (26%) had become lesion free and four (21%) had switched to white types. Although the cohort size does not permit firm conclusions regarding oral cancer risk, the natural course over up to 30 years appears to be benign in the great majority.     

Progressive increase of human papillomavirus carriage rates in potentially malignant and malignant oral disorders with increasing malignant potential

Introduction:  We investigated the potential role of human papillomaviruses (HPVs) in potentially malignant oral disorders, oral leukoplakia (OL) and oral lichen planus (OLP), and in oral squamous cell cancer (OSCC) in an Eastern Hungarian population with a high incidence of OSCC.
Methods:  Excised tumor samples (65 OSCC patients) and exfoliated cells from potentially malignant lesions (from 44 and 119 patients with OL and OLP, respectively) as well as from healthy controls (72 individuals) were analysed. OLPs were classified based on clinical appearance, 61 patients had erosive–atrophic lesions (associated with higher malignancy risk, EA-OLP) and 58 had non-erosive non-atrophic lesions (with lower risk of becoming malignant, non-EA-OLP), respectively. Exfoliated cells collected from apparently healthy mucosa accompanied each lesion sample. HPV was detected by MY/GP polymerase chain reaction (PCR) and genotyped by restriction analysis of amplimers. Copy numbers in lesions were determined using real-time PCR. Prevalence rates, copy number distributions, and association with risk factors and diseases were analysed using chi-square test, t -test, and logistic regression, respectively.
Results:  We detected HPVs significantly more frequently in lesions than in controls ( P  ≤ 0.001 in all comparisons). HPV prevalence increased gradually with increasing severity of lesions (32.8, 40.9, and 47.7% in OLP, OL, and OSCC, respectively). Copy number distribution patterns roughly corresponded to prevalence rates, but OLP and OL were comparable. HPV prevalence differed significantly between EA-OLP and non-EA-OLP groups (42.6 vs. 22.4%); EA-OLP group showed a prevalence similar to that found in OL.
Conclusion:  HPVs may be involved in the development or progression of not only OSCC but also of potentially malignant oral lesions.     

Is alveolar ridge keratosis a true leukoplakia?: A clinicopathologic comparison of 2,153 lesions

BACKGROUND: Alveolar ridge keratosis (ARK) is not widely recognized as a distinct clinicopathologic entity, and it often is included in studies of oral leukoplakia (OL), thereby implying premalignant potential. The authors' objectives were to characterize the clinicopathologic features of ARK and determine whether removing ARK from the OL category would significantly affect the prevalence of dysplasia or carcinoma in OL. METHODS: The authors conducted a retrospective consecutive case review of 477 ARK cases and 1,676 OL cases submitted to their biopsy service from 1995 through 2004. The authors defined ARK as a white plaque without erythema or ulceration and limited to the retromolar pad or edentulous ridge. RESULTS: Microscopically, most ARK cases (97.9 percent) exhibited hyperkeratosis without dysplasia. The few dysplastic cases (2.1 percent) were associated with one or more of the following: verrucous appearance, tobacco or alcohol use, multiple OL lesions and previous oral squamous cell carcinoma. Excluding ARK from OL increased the percentage of OL cases exhibiting dysplasia or carcinoma from 20.2 percent to 24.8 percent. Including versus excluding ARK resulted in good but less than excellent agreement in the OL case definition (kappa = 0.6128). CONCLUSIONS: ARK in patients without high-risk habits or other clinical warning signs appears to be a distinctly different lesion from OL, with a much smaller proportion of dysplasia or carcinoma evident among ARK versus OL cases. However, prospective studies are needed to confirm this hypothesis. CLINICAL IMPLICATIONS: Although most cases clinically consistent with ARK are benign hyperkeratoses, dysplasia or carcinoma can be excluded only by means of biopsy and histopathologic examination.     

Expression of p16 in oral cancer and premalignant lesions

Background:  Expression of p16 has been proposed as a marker for malignant transformation. This study aimed to evaluate p16 expression in oral squamous cell carcinoma (OSCC) and premalignant lesions including oral leukoplakia (OL) with and without dysplasia.
Methods:  Expression of p16 was investigated in 56 samples including OSCC, OL with and without dysplasia, and normal oral mucosa. Expression of p16 was identified by immunohistochemistry, using the CINtecTM p16INK4a Histology Kit. Both nuclear and/or cytoplasmic staining of the keratinocytes were considered to be positive and the percentage of positive cells was calculated.
Results:  Expression of p16 was detected in 3/16 (18.75%) cases of OSCC, in 4/15 (26.7%) cases of OL without dysplasia, and in none of OL with dysplasia and normal mucosa. No significant differences in p16 expression prevalence were found among OSCC, OL with and without dysplasia and normal mucosa. The percentages of positive cells in OSCC and OL without dysplasia were 0.89 and 0.17, respectively. No significant difference in the percentage of positive keratinocytes was found.
Conclusion:  As a marker, p16 is not reliable for oral mucosal dysplasia and malignant transformation.     

口腔粘膜癌变过程中细胞角蛋白CK10和CK13的变化

目的：探讨细胞角蛋白ＣＫ１０和ＣＫ１３在口腔粘膜癌变过程的各阶段组织中的分布和表达强度。方法：用ＬＳＡＢ免疫组化染色方法对口腔正常粘膜、上皮单纯增生、上皮异常增生和口腔磷癌切片进行染色,光镜观察。结果：正常颊粘膜和口底舌腹粘膜基底上层ＣＫ１０表达阴性,ＣＫ１３表达强阳性;上皮过度不全角化时,ＣＫ１０表达可为阳性,ＣＫ１３表达减少;上皮过度正角化时,ＣＫ１０在基底上层呈强阳性表达,ＣＫ１３表达进一步减少甚至缺失。随上皮异常增生程度加重,基底上层细胞ＣＫ１０和ＣＫ１３表达减少甚至缺失。在口腔浸润癌中,不管分化程度如何,ＣＫ１３均表达阴性,而ＣＫ１０在分化较好的癌细胞及癌巢中呈阳性表达。结论：ＣＫ１３表达减少或缺失可作为口腔癌前病变诊断的辅助指标,ＣＫ１０可为口腔癌的分化程度及其预后判定提供帮助。     

The prevalence of oral leukoplakia in 138 patients with oral squamous cell carcinoma

OBJECTIVES: To determine the relationship between oral leukoplakia (OL) and oral squamous cell carcinoma (OSCC), and to evaluate possible differences between those carcinomas with and without associated leukoplakia. MATERIAL AND METHODS: A total of 138 patients were studied at the Stomatology Service of the University General Hospital, Valencia, Spain. These patients were divided into two groups: group 1, patients with oral cancer and leukoplakia, and group 2, patients with OSCC but with no associated premalignant lesions. The relationship between this precancerous lesion and the OSCC was evaluated, as well as the possible clinical and histological differences between the tumours of the two groups. RESULTS: Leukoplakia was detected in 27 (19.56%) patients with OSCC. No differences were found between the two groups regarding age and tumour location. However, statistically significant differences were observed with respect to the form, tumour stage and the presence of adenopathies in the cancers with and without leukoplakia; in that the tumours associated with leukoplakia were diagnosed as being at a more initial stage. CONCLUSIONS: Those patients with OL associated with oral cancer presented with tumours at a less advanced stage than those where no associated leukoplakia existed.     

Incidence rates for oral leukoplakia and lichen planus in a Japanese population

BACKGROUND: Data on the incidence rates of potentially malignant diseases of the oral cavity in different populations is meagre. This is the first study to report on the age-specific incidence of oral leukoplakia and oral lichen planus from an industrialized country. METHODS: Annual screening for oral cancer and pre-cancer was undertaken in Municipal Health Centres in Tokoname city, Japan from 1995 to 1998. A total of 9536 volunteers aged 40-95 years participated in this programme. A cohort of 6340 (67%) subjects attended annual mouth examinations following a negative screen result at entry, allowing 13 072 person-years of observations. Some associated risk factors (tobacco and alcohol misuse) and health-related variables were also evaluated. RESULTS: Over a 4-year follow-up period, 18 new oral leukoplakias (all homogenous; 11 idiopathic and seven tobacco-associated) and 24 oral lichen planus (22 reticular, one erythematous and one ulcerative) were detected at screening and confirmed by re-examination at specialist units. The age-adjusted incidence rate for leukoplakia was 409.2 (95% CI: 90.6-727.9) in male and 70.0 (95% CI: 17.9-121.8) in female per 100,000 person-years observations. For lichen planus, the corresponding rates were 59.7 (95% CI: 7.4-112.1) and 188.0 (95% CI: 96.0-280.1). The age-adjusted incidence rate for tobacco-associated leukoplakia in males was almost 12 times compared with female (560.3 vs. 45.2 per 100,000). Age-specific incidence rates for oral leukoplakia varied by age groups. New oral leukoplakias were more prevalent on gingival/alveolar ridge (33.3%) than in other oral sites, and lichen planus at buccal site (33.3%). Prevalence of smoking habits among those positive for leukoplakia (38.9%) was higher compared with the screen-negatives (26.4%) but these differences did not reach statistical significance (P = 0.232). Regular drinking was not related to occurrence of either oral leukoplakia or oral lichen planus. In cases with diabetes mellitus, relative risk for oral lichen planus adjusted by logistic regression was 6.4 (95% CI: 2.4-17.6), suggesting an association. CONCLUSIONS: The reported incidence rates for oral leukoplakia in this Japanese population are somewhat higher to those reported from India, the risk habits of the two groups being markedly different. The reported rates for oral leukoplakia and lichen planus allow estimation of service needs in specialist oral medicine clinics and for the training of primary care dentists. A high incidence of idiopathic leukoplakia found in this study raises challenges to the strategy of screening high-risk populations aimed at conserving resources.     

Tobacco use increase the number of aneuploid nuclei in the clinically healthy oral epithelium

J Oral Pathol Med (2010) 39 : 605–610 Background: The most important risk factor linked to the development of oral leukoplakia (OL) and oral squamous cell carcinoma (OSCC) is tobacco use. Tobacco contains carcinogens that influence the DNA repair, cell cycle control and may produce chromosomal aberrations. The loss or acquisition of one or more chromosomes is defined as aneuploidy. Methods: Aneuploidy was determined by means of the DNA‐content included in cells obtained by exfoliative cytology and Feulgen’s staining. The cells were collected from the clinically healthy lateral margin of the tongue of non‐smokers without oral lesions, smokers without oral lesions, smokers with OL, and smokers with OSCC, using the CytoBrush^®. Each group was composed of 20 individuals. A Carl Zeiss image analyzer system and the KS300 software were used. Statistical analysis was performed with BioEstat^® software. Results: The mean percentage of aneuploid nuclei was statistically higher in the smokers (79.65%), smokers with OL (68.4%), and smokers with OSCC (93.65%), as compared to non‐smokers (39.3%) (P < 0.05). A trend toward an increase in the aneuploidy of the smokers with OSCC group (P = 0.02), as compared to the non‐smoker group, could be observed. No significant difference could be observed as regards the mean percentage of aneuploid nuclei in relation to duration of tobacco use or the number of the cigarettes smoked. Conclusions: Tobacco use is responsible for an increased number of aneuploid nuclei in the oral epithelium.     

Alteration in the expression of cdk4 and cdk6 proteins in oral cancer and premalignant lesions

J Oral Pathol Med (2010) 39 : 793–799 Background: Cdk4 and cdk6, key players in G1 phase, have been shown to play an important role in the development of oral squamous cell carcinoma (OSCC). This study investigated the expression of these two proteins in OSCC and premalignant lesions including oral leukoplakia (OL) with and without dysplasia and determined if alterations in the expression of these two proteins could be used as markers of malignant transformation. Methods: Expressions of cdk4 and cdk6 were evaluated in 61 samples including OSCC, OL with and without dysplasia and normal oral mucosa using immunohistochemistry method. Nuclear staining of the keratinocytes was considered positive and the percentage of positive cells was calculated. Results: Expression of cdk4 was found in 11/15 (73.33%) OSCC, 13/14 (92.85%) OL with dysplasia, 13/20 (65%) OL without dysplasia and 3/12 (25%) normal mucosa. Expression of cdk6 was detected in 9/15 (60%) OSCC, 3/14 (21.43%) OL with dysplasia, 5/20 (25%) OL without dysplasia and 1/12 (8.33%) normal mucosa. In cdk4 stained specimens, the frequency of positive cases and the percentage of positive cells in normal mucosa was significantly lower than OL with dysplasia and OSCC. For cdk6 staining, the prevalence of positive cases and the percentage of positive cells in normal mucosa were significantly lower than OSCC. Conclusions: Overexpressions of cdk4 and cdk6 were observed in OSCC, indicating that these two proteins play a crucial role in OSCC. The aberrant expression of cdk4 was found in OL with dysplasia, suggesting that cdk4 may be involved in the early event of carcinogenesis.     

Cancer Prevention in the Dental Practice: Oral Cancer Screening and Tobacco Cessation Advice

Objectives : In this paper we describe the proportion of US adults who report receiving oral cancer screening and tobacco cessation counseling and assistance from dentists and other health professionals. Methods : Data from the 1992 National Health Interview Survey (NHIS) Cancer Control Supplement, a nationally representative sample of 12,035 adults 18 years of age and older, are analyzed. Results : In 1992, less than 10 percent of adults reported oral cancer screening by a dentist or hygienist within the past three years. White adults (10.1%; 95% Cl=9.3,10.9) reported an oral cancer screening three times more frequently than black (3.2%; 95% Cl=1.9, 4.5) or Hispanic (3.4%; 95% Cl=2.1, 4.7) adults. About half of adult current smokers had seen a dentist within 12 months, and of those only 24.1 percent (95% Cl=21.7, 26.5) had been advised to quit smoking. Heavy smokers (two or more packs a day) were more likely to have been advised to quit than light (pack or less per day) or occasional smokers. A similar proportion (24.3%; 95% Cl=17.6, 31.0) of white adult men who reported using smokeless tobacco products had been told by a dentist to quit using tobacco. Conclusions : Results from this population-based survey indicate that cancer screening and tobacco cessation advice are underutilized in the dental practice. Increased patient awareness and implementation of screening and tobacco cessation interventions could improve oral cancer incidence and mortality and have a public health benefit for other tobacco-related morbidity and mortality as well.     

Epstein–Barr virus prevalence in oral squamous cell cancer and in potentially malignant oral disorders in an eastern Hungarian population

We tested 65, 44, and 116 patients with oral squamous cell cancer (OSCC), oral leukoplakia (OL), and oral lichen planus (OLP) against 68 age-matched controls for the presence of Epstein–Barr virus (EBV). Apparently healthy mucosa was simultaneously sampled and examined in all patients. Paraffin-embedded tissue sections of all EBV-positive patients with OSCC were examined for latent membrane protein-1 (LMP-1) expression (demonstrable in most EBV-associated malignancies) using immunohistochemistry. The prevalence of EBV in the controls and in OSCC, OL, and OLP lesions was 19.1%, 73.8%, 29.5%, and 46.6%, respectively, and 66.2%, 22.7%, and 31.9% in the healthy mucosa of patients, respectively. The prevalence of EBV in OSCC patients was significantly higher than in controls or in respective samples of the other two patient groups both in the lesion and in the healthy mucosa. Comparisons including only patients with EBV-negative lesions yielded similar results. Lesions of patients with OLP, but not of patients with OL, differed significantly from controls in EBV prevalence. In OSCC, LMP-1 expression was not detected, and EBV carriage was not significantly associated with any risk factors and did not influence the outcome. Although a high prevalence of EBV was found in OSCC, comparable carriage rates on healthy mucosa of patients indicated that an aetiological role of EBV is unlikely.     

Risk factors for oral epithelial dysplasias to become malignant: clinical implications

There is a lack of effective clinical management of oral epithelial dysplasias to reduce their risk of malignant transformation and considerable gaps in knowledge regarding the most effective means of treating such lesions. A retrospective cohort of biopsy-confirmed oral epithelial dysplasias consecutively diagnosed in the period 1995–2014 and followed-up until 2017 was identified from pathology department files. Demographic, clinical and follow-up information was collected. Multivariate Cox proportional-hazards models were performed to evaluate sociodemographic, clinical and pathological factors associated with progression to oral squamous cell carcinoma. The study included 144 oral epithelial dysplasias, of which 42% progressed to oral cancer at the end of follow-up (21 years). Clinical aspect of the lesion was described for 77 (53.5%) of the patients. Treatment, age, grade of the lesion and diagnostic period were independent prognostic factors for progression. When considering only patients with described clinical aspect, only treatment and grade of the lesion were independently associated with cancer. The results from this non-selected retrospective cohort of oral epithelial dysplasias underscore the existing limitations of the current standard-of-care of the patients and provide novel insights on the management of these lesions with and without described clinical aspect. Well-designed, robust prospective studies, a homogenized staging system and multidisciplinary treatment guidelines are warranted.     

H3 and H3.3 histone mRNA amounts and ratio in oral squamous cell carcinoma and leukoplakia

Histone variants (e.g. H3) play an important role in chromatin structure and gene expression regulation of normal cells. Aims of this study were to: (1) estimate H3 and H3.3 histone mRNA expressions and their ratio in oral squamous cell carcinoma (OSCC) and oral leukoplakia (OL); (2) investigate whether H3 and H3.3 variants could play a role in the pathogenesis of OSCC and OL, also conditionally to HPV infection, age, gender, and main habits (tobacco smoking and alcohol drinking) in human beings studied. Twenty-three cases of OSCC and 20 cases of OL were examined in lesion site (LS) and juxtaposed clinically undamaged site (JUS) by RT-PCR for H3 and H3.3 histone mRNA; 13 healthy oral mucosa samples (HS) were investigated in a single site as controls. HPV DNA presence was investigated in the respective exfoliated oral mucosa cells by nested PCR (nPCR: MY09-MY11/GP5-GP6). The data showed that both H3 and H3.3 histone mRNA crude concentrations are higher in OSCC (LS = 2901 +/- 459 ng of H3; JUS = 2699 +/- 658 ng of H3; LS = 3190 +/- 411 ng of H3.3; JUS = 2596 +/- 755 ng of H3.3) than those in OL (LS = 2095 +/- 349 ng of H3; JUS = 2192 +/- 897 ng of H3; LS = 2076 +/- 911 ng of H3.3; JUS = 1880 +/- 654 ng of H3.3) and in HS (2579 +/- 959 ng of H3; 2300 +/- 758 ng of H3.3), although not reaching any statistical significance. Interestingly, ratio of H3/H3.3 mRNA amounts decrease both in OSCC (0.99) and OL (1.009) vs HS (1.121). No association was found for H3 and H3.3 histone mRNA expressions in OSCC and OL with respect to HPV infection and the social-demographical variables considered (P > 0.2). The overall higher expression of H3.3 in damaged tissues up to the ratio inversion in OSCC especially in HPV+ alcohol drinkers (60.0%) represents the most interesting finding, in consideration of the proven ability of alcohol to act as permeability enhancer of human oral mucosa, to alter the mucosal structure and by this dynamics could favour the penetration through the epithelial layers of HPV.     

Effect of cessation of tobacco use on the incidence of oral mucosal lesions in a 10–yr follow-up study of 12 212 users

OBJECTIVE: To study the effect of cessation of tobacco use on the incidence of lichen planus, leukoplakia and other oral mucosal lesions.
DESIGN: A 10–yr cohort study in a rural population of Ernakulam district, Kerala, India.
MATERIAL AND METHODS: Some 12 212 tobacco users were interviewed and examined in a basetine survey and re-examined annually for 10 years. At each examination they were exposed to health educational programs to encourage them to quit their tobacco use. The incidence rates were calculated using person-years method among those who stopped their tobacco use and all others.
RESULTS: A total of 77 681 person-years of observation accrued among men and 32 544 among women. Among men 6.5% of these and among women 14.4% were in the stopped category. The incidence of oral lichen planus did not show any consistent association with cessation of tobacco habits (incidence ratio I.35) but for leukoplakia there was a substantial drop in the incidence after cessation (incidence ratio 0.3I). Several other tobacco-associated oral mucosal lesions such as oral lichen planus-like lesion, smoker's palate, preteukoplakia, central papillary atrophy of the tongue and leukoedema showed either zero, or very small incidence, after cessation. CONCLUSION: The reported association between tobacco use and lichen planus appears to be indirect but for all other lesions it is direct. The cessation of tobacco use led to a substantial fall in the incidence of leukoplakia and other lesions implying a reduced risk for oral cancer after cessation of tobacco use.     

Metallothionein and p-Akt proteins in oral dysplasia and in oral squamous cell carcinoma: an immunohistochemical study

Background:  Oral leukoplakia (OL) is the main potentially malignant lesion of the oral cavity, and oral squamous cell carcinoma (OSCC) accounts for more than 95% of all malignant neoplasms in the oral cavity. Therefore, the aim of this study was to verify the immunoexpression of p-Akt and Metallothionein (MT) proteins in dysplasic and neoplasic oral lesions.
Methods:  Immunohistochemical studies were carried out on 10 normal epithelium, 30 OL and 15 OSCC paraffin-embedded samples. Immunoperoxidase reaction for p-Akt and MT proteins was applied on the specimens, and the positivity of the reactions was calculated for 1000 epithelial cells.
Results:  Using the ANOVA and the Tukey's post hoc statistical analyses, it was observed a significant difference in the immunoexpression for p-Akt and MT when the OSCC samples were compared with normal and dysplasic epithelial groups. In addition, the Pearson's correlation test showed a significant correlation between the proteins' expression.
Conclusion:  Based on the data obtained, p-Akt and MT activation may play an important role in the conversion of a potentially malignant oral lesion to a malignant carcinoma since its earlier stages.     

Decline in the rate of oral opportunistic infections following introduction of highly active antiretroviral therapy

In recent years the management of human immunodeficiency virus (HIV)-positive individuals has been based on highly active antiretroviral therapy (HAART) comprising a combination of nucleoside analogues or the combination of these agents with protease inhibitors. The aim of the present study was to describe the prevalence of oral lesions in a cohort of 103 HIV-seropositive patients on HAART, to compare these data with the prevalence of lesions prior to HAART and to correlate these finding with the immunologic data. A total of 103 HIV-seropositive patients on HAART were selected. Oral lesions associated with HIV infection and immunological parameters were registered. On re-examination 6 months after the first evaluation, 61/103 patients were available. Comparing the prevalence of oral lesions before and after the onset of HAART, the number of oral lesions was significantly lower (P=0.001). The number of CD4+ cells increased and the viral load decreased significantly after initiation of HAART (P=0.001 and P= 0.0001). On re-examination 6 months later, the prevalence of lesions again decreased significantly (P=0.001). The immunological benefits of HAART may prevent HIV-associated oral lesions in patients with advanced HIV disease. Our results showed that oral manifestations decrease on HAART, but in four patients the immunological effects of therapy did not provide sufficient protection against human papillomavirus (HPV)induced lesions.     

Oral cancer knowledge and examination experiences among North Carolina adults

OBJECTIVE: This study assesses knowledge of oral cancer risk factors, clinical signs, and oral cancer examination experience among North Carolina adults. METHODS: A statewide random digit dial, computer-assisted telephone interview was conducted in 2002. Data from 1,096 respondents, with a response rate of 62 percent, were poststratified to 2000 census data by sex, race, and age group to produce population-based estimates. Knowledge of one sign of oral cancer, four or more risk factors for oral cancer, and having ever had an oral cancer examination were compared in logistic regression models using normalized weights. RESULTS: Fourteen (95% confidence interval [CI] +/-2) percent of adults had never heard of oral or mouth cancer. Risk factor knowledge was high for 56 percent (95% CI+/-3) and associated in a logistic regression model with younger age, feeling personal factors cause cancer, and nonuse of snuff. One sign of oral cancer (sore/lesion, red or white patch in mouth, and bleeding in the mouth) was correctly identified by 53 percent (95% CI+/-3) with significantly more correct responses from younger people, nonsmokers, and some college education. Only 29 percent (95% CI+/-3) reported ever having had an oral cancer examination when this procedure was described. Most respondents reported exams performed by dentists. In a weighted logistic regression model, older age, being dentate, nonsmokers, alcohol users, and those with some college education were significantly more likely to report having ever had an oral cancer examination. CONCLUSIONS: Although there is moderate knowledge of signs and risk factors for oral cancer among North Carolina adults, knowledge deficits remain. Oral cancer examinations need to be increased, particularly among tobacco smokers.     

Polymorphisms in the apoptosis‐associated genes FAS and FASL and risk of oral cancer and malignant potential of oral premalignant lesions in a Taiwanese population

J Oral Pathol Med (2010) 39: 155–161 Background: Our aim was to measure the relationship of FAS (?1377G>A and ?670A>G), FASL (?844C>T) gene variants and risk of oral cancer. Methods: Polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP) analysis was used to determine the FAS and FASL polymorphisms in 294 oral squamous cell carcinoma (OSCC), 53 oral submucous fibrosis (OSF), and 84 oral leukoplakia (OL) patients, as well as in 333 healthy controls. A standardized questionnaire was applied to collect demographic data, and potential confounding factors. JMP statistical software was used to analyze the association. Results: FAS and FASL polymorphisms were not correlated with OSCC development or the malignant potential of OL by simple and multivariate logistic regression. However, a two‐ to fourfold difference in the risks of betel quid chewing, alcohol consumption, and smoking on OSCC development were observed between participants with different FAS polymorphisms. FAS polymorphisms were significantly correlated with the malignant potential of OSF. Multivariate logistic regression analysis indicated that FAS A_?1377‐G_?670 vs. G_?1377‐A_?670 haplotype (OR = 2.26, 95% CI = 1.16–4.41) was correlated with the malignant potential of OSF. Conclusions: We suggest that FAS and FASL polymorphisms are not significantly correlated with OSCC development or malignant potential of OL. The impact of substance usage on OSCC development could be differentiated by FAS polymorphisms. FAS A_?1377‐G_?670 haplotype may play a role in the malignant potential of OSF.     

Oral leukoplakia in China: a review

Background

Most prevalence studies on oral leukoplakia (OL) in China have been published in the Chinese language. The present review on the literature in Chinese aimed at making the data available to colleagues who are not familiar with the Chinese language.

Methods

The overall rate and 95% confidence interval of OL were calculated using Excel 2003.

Results

Overall prevalence of OL was 9.18% (95%CI?=?9.06-9.30%). Gender ratio of prevalence was 8.03:1 (males/females). Prevalence was high in age groups over 40 years with the highest in the group aged 60-69 years (21.04%, 95%CI?=?19.95-22.13%). The buccal mucosa was most commonly affected (47.08%, 95%CI?=?46.52-47.64%), followed by lip (39.09%), palate (9.85%), gingiva (1.80%), and tongue (1.46%). The prevalence in smokers was 23.43% and in non-smokers 1.93%. Among three variants of smoking, the traditional Hanyan pipe smoking carried the highest risk for the development of OL followed by cigarette and Shuiyan water pipe smoking. The rate of alcohol drinkers with OL was 54.50% and 22.21% in individuals without OL. No case of oral cancer was found in six surveys.

Conclusions

The present data on the prevalence of OL in China are comparable to those in other parts of the world. Some traditional smoking habits, however, are particular to certain regions of China.     

前臂皮瓣与胸大肌皮瓣在口腔癌手术缺损修复中的应用

目的:观察前臂皮瓣和胸大肌皮瓣修复口腔癌手术缺损的治疗效果。方法:30例口腔癌患者在常规联合根治术后,随机分为A、B组,每组15例。A组采用前臂桡侧皮瓣游离移植同期修复口腔癌术后口腔颌面部缺损,B组采用胸大肌皮瓣同期修复口腔癌术后口腔颌面部组织缺损;对比两组的修复效果。结果:A组13例(86.67%)前臂皮瓣顺利成活,B组皮瓣成活率100%。A组中有6例患者虎口感觉消失、4例患者供区颜色极深或极浅;B组中有4例女性患者术后两侧乳房不对称。结论:前臂皮瓣和胸大肌皮瓣修复口腔癌手术缺损均具有较高的成功率,两种皮瓣均适用于口腔癌手术缺损修复。