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In the past decades several definitions of oral leukoplakia have been proposed, the last one, being authorized by the World Health Organization (WHO), dating from 2005. In the present treatise an adjustment of that definition and the 1978 WHO definition is suggested, being : “A predominantly white patch or plaque that cannot be characterized clinic...
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... after elimination of the suspected mechanical irritation (e.g However, in case of persistence, it seems safe practice to consider a diagnosis of Candida-associated leukopla- kia. -3.3 Frictional "keratosis" Another possible reversible white lesion is the frictional lesion caused by mechanical irritation, e.g. vigorously brushing of the teeth (Fig. 2). This lesion is sometimes referred to as "frictional keratosis". The term "lesion" is preferred because "keratosis" is actually a histopatho- logical term. There may be some overlap with the pre- viously discussed alveolar ridge keratosis (see ad ...
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Proliferative verrucous leukoplakia (PVL) is a rare form of oral leukoplakia, which was first described in 1985 by Hansen et al. Since then, various published case series have presented PVL as a disease with aggressive biological behavior due to its high probability of recurrence and a high rate of malignant transformation, usually higher than 70%....
Citations
... The most frequent oral mucosa sites affected by OLK are the buccal mucosa, the floor of the mouth, and the tongue, but all areas of the oral mucosa can be involved [5]. The most common clinical classification of OLK divides it into a homogeneous form and a nonhomogeneous form, with verrucous, speckled, and nodular subtypes [6]. ...
... The demographic data recorded were gender, age, and smoking status. The clinical form of the OLK lesions was classified, as recommended by van der Waal, 2015 [6], as homogenous or non-homogenous (further categorized as verrucous, speckled, or nodular). We also recorded the number of lesions (single or multiple lesions) and the size of the lesions: smaller than 2 cm 2 , between 2 and 4 cm 2 , and larger than 4 cm 2 . ...
Background/Objectives: Oral leukoplakia (OLK) is an oral mucosal lesion classified in the oral potentially malignant disorder group and is associated with an increased risk of malignant transformation (MT). The aim of this study was to compare the clinical and histopathological features of two OLK groups, a group of smokers and a group of non-smokers. Methods: In this retrospective study, a cohort of 154 patients with OLK was divided into two groups based on the presence of smoking as a major risk factor. OLK diagnoses were established via clinical and histopathological examination. Results: Females were more abundant in the non-smoking group than in the smoking group, where males were more abundant (p < 0.001). The average age of the smokers was lower than that of the non-smokers (p = 0.003). In the smokers, the buccal mucosa was most frequently affected, while in the non-smokers, the gums and the tongue were primarily involved (p = 0.016). In female smokers, involvement of the buccal area and multiple-site involvement were statistically significantly more frequently observed compared to that in female non-smokers (p = 0.006). Non-dysplastic lesions were predominant in both groups, with severe dysplasia observed more frequently in the non-smokers than in the smokers. MT was higher in the non-smoker group compared to that in the smoker group. Conclusions: OLK in smokers is different from OLK in non-smokers concerning female gender involvement, site location, the number of lesions, and the MT rate.
... Quando são observadas projeções em suas superfícies, são denominadas leucoplasia verruciforme ou verrucosa e quando as lesões apresentarem áreas brancas e áreas vermelhas, a denominação leucoeritroplasia ou leucoplasia salpicada é utilizada.15 Dependendo da quantidade desses aspectos clínicos descritos anteriormente, em uma mesma lesão, as leucoplasias são classificadas em homogêneas e não homogêneas (heterogêneas).7 Embora o tipo clínico mais comum da leucoplasia seja do tipo homogêneo, as lesões não homogêneas estão relacionadas com um maior risco de transformação maligna.38,39 A leucoplasia é um termo clínico e não apresenta uma alteração histopatológica específica.13 ...
Objetivo: Realizar uma revisão da literatura sobre as lesões orais classificadas como desordens potencialmente malignas (DPM) de acordo com 5° edição da classificação dos tumores de cabeça e pescoço da Organização Mundial da Saúde. Métodos: Foi utilizada a base de dados do PubMed, não sendo estabelecido um intervalo temporal, com o intuito de se obter o maior número de publicações possíveis, desde que as mesmas se encontrassem em inglês. Resultados: A prevalência mundial das DPM varia de 0,9 a 5%, sendo a leucoplasia, líquen plano oral e lesão liquenoide oral (LLO) as mais comuns e a língua e mucosa jugal os sítios mais acometidos. A taxa de transformação é mais elevada na leucoplasia verrucosa proliferativa, lesões no palato relacionadas ao fumo invertido, eritroplasia e fibrose submucosa e varia entre os grupos populacionais. Conclusão: Na mais recente classificação das DPM orais estabelecida pela OMS na 5° edição da Classificação dos Tumores de Cabeça e Pescoço, foram adicionadas, no grupo de DPM, a LLO, manifestações orais da doença do enxerto versus hospedeiro (DEVH) e síndromes de câncer familiar, como anemia de Fanconi, xeroderma pigmentoso, síndrome de Li Fraumeni, síndrome de Bloom, ataxia telangiectasia e síndrome de Cowden. Em contrapartida, existem, até o momento, evidências insuficientes sobre o potencial maligno da candidíase hiperplásica crônica e da glossite sifilítica, tendo sido, portanto, excluídas da lista de DPM.
... A definitive clinical diagnosis of leukoplakia was considered when a negative result was obtained, even after the elimination of suspected etiologic factors, e.g., mechanical irritation, during a follow-up period of 6 weeks. 27 Leukoplakia is a classic precursor lesion of oral cancer. 28 Such lesions should be managed properly to prevent further severe dysplastic changes. ...
... Oral leukoplakia refers to patchy damage of white or grayishwhite keratotic lesions occurring only on the oral mucosa, of which WHO defines it as 'A predominantly white lesion of the oral mucosa that cannot be characterized by any other definable lesion' (1), and it is a common non-infectious, chronic disease, which can occur in all the mucous membranes of the oral cavity but is most frequent in the buccal and lingual areas, and is an Oral potentially malignant disorders (OPMDs) (2). In addition to white color, white spots can also show red and white damage. ...
Background
Several existing studies have shown a correlation between some of the blood and urine biomarkers and oral leukoplakia (OLK). However, the causality of this relationship remains uncertain. Thus, this study aimed to examine the causal association between 35 blood and urine biomarkers and OLK.
Methods
Single nucleotide polymorphisms (SNPs) associated with 35 blood and urine biomarkers were selected as instrumental variables (IVs) using a two-sample Mendelian randomization(MR) study to assess the causal relationship between the biomarkers and the risk of oral leukoplakia. We used the inverse variance weighted (IVW) method as the main analysis. Furthermore, several sensitivity analyses were performed to assess heterogeneity, horizontal pleiotropy, and stability.
Results
Based on the selection criteria of the Inverse Variance Weighted (IVW) method, the analysis found that 5 blood and urine biomarkers were significantly associated with the development of leukoplakia, of which the results of IVW showed that abnormalities of Apolipoprotein B (Apo B), Cholesterol, Low-density Lipoprotein (LDL), Triglycerides (TG) promoted the development of oral leukoplakia, and Non Albumin Protein (NAP) had a protective effect on the development of oral leukoplakia. We then performed a Bonferroni correction for these results, and after correction Apo B was still causally associated with the development of oral leukoplakia (IVW P<0.0007), whereas the other four biomarkers could only provide some evidence of predisposition.
Conclusion
Our two-sample Mendelian randomization study supports the existence of a causal relationship between these five blood and urine biomarkers and the occurrence of oral leukoplakia, and provides evidence for a number of risk and protective factors for the development of oral leukoplakia; however, the definitive mechanisms for the occurrence and development of oral leukoplakia still remain to be elucidated, and further studies on these relevant mechanisms are still needed.
... The prevalence of leukoplakia ranges between 1.5% and 4% throughout the world, whereas, in India, this range is wider with an estimated value of 0.2%-4.8% [8,9]. ...
Background: Squamous cell carcinoma of the oral cavity may show precursor lesions, termed as potentially malignant disorders, of which leukoplakia is the most frequent one. Oral leukoplakia is a clinical diagnosis for which the histological diagnosis may be either hyperplasia or oral epithelial dysplasia (OED) and sometimes even oral squamous cell carcinoma (OSCC). Cancer stem cells (CSCs), identified in various tumors, are a specific group of cells that exhibit the properties of self-renewal and differentiation. Among the various biomarkers that identify CSCs, the transcription factor NANOG is considered to be a significant one.
Aim: In this study, we intend to identify and compare the immunohistochemical expression of NANOG in OSCC, OED, and normal oral mucosa.
Methodology: Tissue blocks of OSCC (n=28), OED (n=28), and normal oral mucosa (n=28) were used in this study. Specimens were immunohistochemically analyzed for NANOG expression. The results were statistically analyzed using one-way ANOVA, Games-Howell post hoc, and Student t-test. Statistical Product and Service Solutions (SPSS, version 21; IBM SPSS Statistics for Windows, Armonk, NY) software was used for performing the statistical analysis, and the level of significance was set as 0.05.
Observations: NANOG expression was higher in OSCC when compared to oral dysplasias and normal oral mucosa, in decreasing order. A significantly higher histo-score and labeling index score were observed in OSCC and oral dysplasias compared to normal oral mucosa (p=<0.001).
Conclusion: The expression levels of NANOG were positively correlated with disease progression in OSCC, implicating that NANOG can be used as a surrogate marker of oral oncogenesis and prognosis. Therefore, decoding the molecular mechanisms of NANOG regulation in the progression of cancer helps in developing new therapeutic strategies for oral cancer.
... highlighting the need for histological examination (6). OPMDs make up to 17-35% of all newly diagnosed instances of oral cancer and they progress to cancer on average at a rate of 0.7% to 2.9% each year (7). ...
... According to the van der Waal criteria, a non-scrapable mixed red and white lesion with no other known cause than tobacco was classified as non-homogenous leukoplakia. 16 growth with central necrosis and rolled borders. Following a clinical examination and palpation, the growth was classified using the TNM classification. ...
Objectives
The aim of this study was to assess and compare the serum and salivary levels of Vitamin D in patients with oral potentially malignant disorders (OPMD) and Oral squamous cell carcinoma (OSCC) with healthy controls.
Method
This cross-sectional study was carried out among 60 patients reporting to the department of Oral Medicine and Radiology, and included patients with OPMDs, OSCC and healthy controls. The Vitamin D levels were estimated using the chemiluminescence immunoassay. One-way ANOVA was used to compare mean and statistical difference between the groups. Tukey's post HOC test calculated for inter group difference. Serum and salivary Vitamin D levels were corelated with Pearson's coefficient. The values of p < 0.005 was considered as significant.
Results
The levels of Vitamin D were decreased in study group as compared to controls both in serum and saliva. (p < 0.001). Between serum and salivary Vitamin D levels, a strong association was discovered using the Pearson's coefficient value of 0.737 (p < 0.001)
Conclusion
In this study, patients with both OPMDs and OSCC had Vitamin D insufficiency & deficiency. Vitamin D level assessment should be included as a standard component of routine investigations for these individuals.
... In 1984, the Malmo Conference added " not associated with any physical or chemical causative agent except use of tobacco" [11]. By 1996, the definition was used widely [12], and was formally published in 1997 [13]. ...
Background
Oral leukoplakia(OLK) is a common oral potentially malignant disorder. The global prevalence of solely OLK was published in 2003, while the prevalence varied among different studies. In recent years, large-scale summary and definition-related analyses obtain insufficient attention. This study aimed to perform a systematic review of prevalence studies of oral leukoplakia and assess predisposing factors of its occurrence.
Methods
The search terms ("Oral leukoplakia" OR OLK OR leukoplakia) AND (prevalence OR incidence OR epidemiology) were searched in databases (Pubmed, Embase, Scopus, and Web of Science) for OLK studies published from January 1996 until December 2022. The estimated prevalence calculation and risk of bias analysis used STATA 16.0.
Results
We obtained 69 studies, including 1,263,028 participants, from 28 countries, and 6 continents. The prevalence was 1.39%, varying from 0.12 to 33.33%. The overall pooled estimated prevalence of OLK was 2.23% for population-based studies, 1.36% for clinic-based population studies, and 9.10% for specific populations. The pooled prevalence in different continents ranged from 0.33 to 11.74% with a statistical difference in the population-based calculation. The estimated prevalence of OLK was higher in males than in females. Those who smoked and consumed alcohol had a higher prevalence than those who did not.
Conclusion
Combining data from 69 published studies, the prevalence of OLK was determined as 1.39% and the pooling estimated global prevalence was 3.41%. The prevalence was relatively consistent and stable across different continents and different definitions. A higher pooled estimated prevalence was found among males, those aged over 60 years old, smokers, and alcohol consumers. The results from the included studies in this systematic review revealed that the prevalence was relatively consistent and stable across various definitions and continents, which may help in developing global treatment and prevention strategies for oral leukoplakia.
... Patient with a discoid lupus erythematosus lesion on the buccal mucosa. videnskab & klinik ∕ oversigtsartikel rende anden sygdom" (14). Leukoplaki er således en klinisk diag nose, der stilles efter udelukkelse af anden tilgrundliggende syg dom (fx plaklignende OLP, DLE, håret leukoplaki, leukødem eller white sponge nevus) eller årsag (fx traumatisk påvirkning af slimhinden) til den hvide forandring. ...
White lesions can be classified according to aetiology and pathogenesis, but in many cases, it is not possible to identify the triggering cause or underlying mechanism, and some conditions are idiopathic. Some white mucosal lesions occur as a reaction to continuous mechanical, thermal or chemical influence, e.g. friction or smoking, while others can be manifestations of for example genetic abnormalities, mucocutaneous diseases or chronic inflammation. It may be necessary to take a biopsy for final verification of the diagnosis. Whitish changes are usually an expression of keratinisation of normally non-keratinized epithelium, increased degree of keratinisation (hyperkeratinisation) and/or increased epithelial thickness (hyperplasia). Inter-/intracellular oedema in the epithelium (e.g. leukoedema)
can also appear as white lesions, and white gelatinous plaques that can be scraped off from the mucosal surface can be a sign of e.g. pseudomembranous candidiasis. Necrosis of the epithelium gives the tissue a grey-white appearance (e.g. necrotising gingivitis). Finally, changes in the connective tissue can mask
the blood vessels, whereby the mucous membrane appears paler than normal (e.g. lichen sclerosus). This article reviews some of the most common oral mucosal diseases and systemic diseases that manifest with white oral mucosal lesions, and are essential in relation to differential diagnosis.
... Подавляющее большинство злокачественных новообразований слизистой оболочки ротовой полости (СОРП) приходится на плоскоклеточный рак. Плоскоклеточный рак СОРП развивается, как правило, в исходе предшествующих потенциально злокачественных заболеваний, ведущим из которых является лейкоплакия [1,2]. ...
Background. The vast majority of malignant neoplasms of the oral mucosa refer to squamous cell carcinomas. The development of squamous cell carcinoma of the oral mucosa is often promoted by previous potentially malignant diseases, with oral leukoplakia dominating among them.
Objective. To determine the clinical significance of the pathogenicity of somatic mutations in oral mucosal leukoplakia.
Methods. The study material included 24 samples of abnormal epithelium of the oral mucosa from leukoplakia patients. QIAamp DNA FFPE Tissue Kit (Qiagen, Germany) was used for deoxyribonucleic acid (DNA) extraction from the samples. DNA sequencing was performed using IlluminaNextSeq 550 sequencer and TruSight™ Oncology 500 DNA Kit For Use with NextSeq (Illumina, USA). All DNA extractions from biological samples, preparation and sequencing of DNA libraries were performed step-by-step in strict accordance with the guidelines provided with the respective reagent kits. Bioinformatics analysis was carried out using specific software Illumina Base Space (Illumina, USA) and Galaxy Project (The Galaxy Community, a non-profit international project) according to current guidelines. The desired power of the study accounted for 90%. Two Proportions Z test was performed by means of The Sample Size Calculation of Statistica 12 (StatSoft, Inc.) with the set option “one-tailed hypothesis”, because it was initially assumed that pathogenic (oncogenic) genetic variants occur in the tissue of oral leukoplakia much more frequently than in the human reference genome used for sequence alignment.
Results. The pathogenic somatic mutations in the TP53 , KRAS , APC , NRAs and BRAF genes, identified in this study, alone or in combination, are highly likely (hazard ratio 3000-11000) to be associated with the development of oral mucosal leukoplakia and low-grade epithelial dysplasia. The multiplicity of pathogenic and likely pathogenic genetic variants associated with epithelial dysplasia, as well as the fact that a number of variants do not occur in all patients, suggests that the same histotype of oral mucosal dysplasia may develop under the influence of different mutations.
Conclusion. The pathogenic and likely pathogenic variants of the TP53, KRAS, APC, NRAS and BRAF genes, identified in this study, alone or in combination, are highly likely (hazard ratio 3000–11000) to be associated with the development of leukoplakia and low-grade epithelial dysplasia.
