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Gary P Moran - One of the best experts on this subject based on the ideXlab platform.
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the microbiome of potentially malignant oral Leukoplakia exhibits enrichment for fusobacterium leptotrichia campylobacter and rothia species
Frontiers in Microbiology, 2017Co-Authors: Abdrazak Amer, Claire M Healy, Sheila Galvin, Gary P MoranAbstract:Oral Leukoplakia presents as a white patch on the oral mucosa and is recognised as having significant malignant potential. Although colonisation of these patches with Candida albicans is common, little is known about the bacterial microbiota of these patches. In the current study we analysed the microbiome of oral Leukoplakia in 36 patients compared to healthy mucosal tissue from the same patients and healthy control subjects to determine if specific microbial enrichments could be identified early in the malignant process that could play a role in progression. This was carried out by sequence analysis of the V1-V2 region of the bacterial 16S rRNA gene using the Illumina MiSeq. Oral Leukoplakia exhibited increased abundance Fusobacteria and reduced levels of Firmicutes (Metastats P <0.01). Candida colonisation was also more prevalent in Leukoplakia patients relative to healthy controls (P 0.025). Bacterial colonisation patterns on oral Leukoplakia were highly variable and five distinct bacterial clusters were discerned. These clusters exhibited co-occurrence of Fusobacterium, Leptotrichia and Campylobacter species (Pearson P <0.01), which is strikingly similar to the microbial co-occurrence patterns observed on colorectal cancers (Warren et al., 2013). Increased abundance of the acetaldehydogenic microorganism Rothia mucilaginosa was also apparent on oral Leukoplakias from lingual sites (P 0.0012). Severe dysplasia was associated with elevated levels of Leptotrichia spp. and Campylobacter concisus (P <0.05). Oral Leukoplakia exhibits an altered microbiota that has similarities to the microbiome of colorectal cancer.
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the microbiome of oral Leukoplakia shows enrichment in fusobacteria and rothia species
Journal of Oral Microbiology, 2017Co-Authors: Abdrazak Amer, Claire M Healy, Sheila Galvin, Gary P MoranAbstract:ABSTRACTThe current study was carried out to determine if changes in the oral microbiome were associated with oral Leukoplakia. Swabs of oral Leukoplakias were taken from 36 patients. Contralateral normal tissue was also swabbed. Swabs from 35 control patients without symptoms of Leukoplakia were also taken. DNA was extracted and the V1V2 region of the 16s rRNA gene was sequenced using the Illumina MiSeq and analysed using the Mothur software package.The structure of oral mucosal communities was most affected by smoking and the location of the site (AMOVA p < 0.01). Analysis of the constituents of these communities using LEfSe showed that Fusobacterium sp. and Leptotrichia sp. were enriched on Leukoplakia sites. Patients with Leukoplakia also showed enrichment for Rothia mucilaginosa and Campylobacter sp. Quantitative RT-PCR also showed that Leukoplakias from lingual sites were more likely to be colonised by Candida sp. Analysis of these enrichments identified specific co-localisation patterns (Pearson co...
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The microbiome of oral Leukoplakia shows enrichment in Fusobacteria and Rothia species
Taylor & Francis Group, 2017Co-Authors: Abdrazak Amer, Sheila Galvin, Claire Healy, Gary P MoranAbstract:The current study was carried out to determine if changes in the oral microbiome were associated with oral Leukoplakia. Swabs of oral Leukoplakias were taken from 36 patients. Contralateral normal tissue was also swabbed. Swabs from 35 control patients without symptoms of Leukoplakia were also taken. DNA was extracted and the V1V2 region of the 16s rRNA gene was sequenced using the Illumina MiSeq and analysed using the Mothur software package. The structure of oral mucosal communities was most affected by smoking and the location of the site (AMOVA p < 0.01). Analysis of the constituents of these communities using LEfSe showed that Fusobacterium sp. and Leptotrichia sp. were enriched on Leukoplakia sites. Patients with Leukoplakia also showed enrichment for Rothia mucilaginosa and Campylobacter sp. Quantitative RT-PCR also showed that Leukoplakias from lingual sites were more likely to be colonised by Candida sp. Analysis of these enrichments identified specific co-localisation patterns (Pearson correlation P
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The Microbiome of Potentially Malignant Oral Leukoplakia Exhibits Enrichment for Fusobacterium, Leptotrichia, Campylobacter, and Rothia Species
Frontiers Media S.A., 2017Co-Authors: Abdrazak Amer, Claire M Healy, Sheila Galvin, Gary P MoranAbstract:Oral Leukoplakia presents as a white patch on the oral mucosa and is recognized as having significant malignant potential. Although colonization of these patches with Candida albicans is common, little is known about the bacterial microbiota of these patches. In the current study we analyzed the microbiome of oral Leukoplakia in 36 patients compared to healthy mucosal tissue from the same patients and healthy control subjects to determine if specific microbial enrichments could be identified early in the malignant process that could play a role in the progression of the disease. This was carried out by sequence analysis of the V1–V2 region of the bacterial 16S rRNA gene using the Illumina MiSeq. Oral Leukoplakia exhibited increased abundance of Fusobacteria and reduced levels of Firmicutes (Metastats P < 0.01). Candida colonization was also more prevalent in Leukoplakia patients relative to healthy controls (P = 0.025). Bacterial colonization patterns on oral Leukoplakia were highly variable and five distinct bacterial clusters were discerned. These clusters exhibited co-occurrence of Fusobacterium, Leptotrichia, and Campylobacter species (Pearson P < 0.01), which is strikingly similar to the microbial co-occurrence patterns observed on colorectal cancers (Warren et al., 2013). Increased abundance of the acetaldehydogenic microorganism Rothia mucilaginosa was also apparent on oral Leukoplakias from lingual sites (P 0.0012). Severe dysplasia was associated with elevated levels of Leptotrichia spp. and Campylobacter concisus (P < 0.05). Oral Leukoplakia exhibits an altered microbiota that has similarities to the microbiome of colorectal cancer
Abdrazak Amer - One of the best experts on this subject based on the ideXlab platform.
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the microbiome of potentially malignant oral Leukoplakia exhibits enrichment for fusobacterium leptotrichia campylobacter and rothia species
Frontiers in Microbiology, 2017Co-Authors: Abdrazak Amer, Claire M Healy, Sheila Galvin, Gary P MoranAbstract:Oral Leukoplakia presents as a white patch on the oral mucosa and is recognised as having significant malignant potential. Although colonisation of these patches with Candida albicans is common, little is known about the bacterial microbiota of these patches. In the current study we analysed the microbiome of oral Leukoplakia in 36 patients compared to healthy mucosal tissue from the same patients and healthy control subjects to determine if specific microbial enrichments could be identified early in the malignant process that could play a role in progression. This was carried out by sequence analysis of the V1-V2 region of the bacterial 16S rRNA gene using the Illumina MiSeq. Oral Leukoplakia exhibited increased abundance Fusobacteria and reduced levels of Firmicutes (Metastats P <0.01). Candida colonisation was also more prevalent in Leukoplakia patients relative to healthy controls (P 0.025). Bacterial colonisation patterns on oral Leukoplakia were highly variable and five distinct bacterial clusters were discerned. These clusters exhibited co-occurrence of Fusobacterium, Leptotrichia and Campylobacter species (Pearson P <0.01), which is strikingly similar to the microbial co-occurrence patterns observed on colorectal cancers (Warren et al., 2013). Increased abundance of the acetaldehydogenic microorganism Rothia mucilaginosa was also apparent on oral Leukoplakias from lingual sites (P 0.0012). Severe dysplasia was associated with elevated levels of Leptotrichia spp. and Campylobacter concisus (P <0.05). Oral Leukoplakia exhibits an altered microbiota that has similarities to the microbiome of colorectal cancer.
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the microbiome of oral Leukoplakia shows enrichment in fusobacteria and rothia species
Journal of Oral Microbiology, 2017Co-Authors: Abdrazak Amer, Claire M Healy, Sheila Galvin, Gary P MoranAbstract:ABSTRACTThe current study was carried out to determine if changes in the oral microbiome were associated with oral Leukoplakia. Swabs of oral Leukoplakias were taken from 36 patients. Contralateral normal tissue was also swabbed. Swabs from 35 control patients without symptoms of Leukoplakia were also taken. DNA was extracted and the V1V2 region of the 16s rRNA gene was sequenced using the Illumina MiSeq and analysed using the Mothur software package.The structure of oral mucosal communities was most affected by smoking and the location of the site (AMOVA p < 0.01). Analysis of the constituents of these communities using LEfSe showed that Fusobacterium sp. and Leptotrichia sp. were enriched on Leukoplakia sites. Patients with Leukoplakia also showed enrichment for Rothia mucilaginosa and Campylobacter sp. Quantitative RT-PCR also showed that Leukoplakias from lingual sites were more likely to be colonised by Candida sp. Analysis of these enrichments identified specific co-localisation patterns (Pearson co...
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The microbiome of oral Leukoplakia shows enrichment in Fusobacteria and Rothia species
Taylor & Francis Group, 2017Co-Authors: Abdrazak Amer, Sheila Galvin, Claire Healy, Gary P MoranAbstract:The current study was carried out to determine if changes in the oral microbiome were associated with oral Leukoplakia. Swabs of oral Leukoplakias were taken from 36 patients. Contralateral normal tissue was also swabbed. Swabs from 35 control patients without symptoms of Leukoplakia were also taken. DNA was extracted and the V1V2 region of the 16s rRNA gene was sequenced using the Illumina MiSeq and analysed using the Mothur software package. The structure of oral mucosal communities was most affected by smoking and the location of the site (AMOVA p < 0.01). Analysis of the constituents of these communities using LEfSe showed that Fusobacterium sp. and Leptotrichia sp. were enriched on Leukoplakia sites. Patients with Leukoplakia also showed enrichment for Rothia mucilaginosa and Campylobacter sp. Quantitative RT-PCR also showed that Leukoplakias from lingual sites were more likely to be colonised by Candida sp. Analysis of these enrichments identified specific co-localisation patterns (Pearson correlation P
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The Microbiome of Potentially Malignant Oral Leukoplakia Exhibits Enrichment for Fusobacterium, Leptotrichia, Campylobacter, and Rothia Species
Frontiers Media S.A., 2017Co-Authors: Abdrazak Amer, Claire M Healy, Sheila Galvin, Gary P MoranAbstract:Oral Leukoplakia presents as a white patch on the oral mucosa and is recognized as having significant malignant potential. Although colonization of these patches with Candida albicans is common, little is known about the bacterial microbiota of these patches. In the current study we analyzed the microbiome of oral Leukoplakia in 36 patients compared to healthy mucosal tissue from the same patients and healthy control subjects to determine if specific microbial enrichments could be identified early in the malignant process that could play a role in the progression of the disease. This was carried out by sequence analysis of the V1–V2 region of the bacterial 16S rRNA gene using the Illumina MiSeq. Oral Leukoplakia exhibited increased abundance of Fusobacteria and reduced levels of Firmicutes (Metastats P < 0.01). Candida colonization was also more prevalent in Leukoplakia patients relative to healthy controls (P = 0.025). Bacterial colonization patterns on oral Leukoplakia were highly variable and five distinct bacterial clusters were discerned. These clusters exhibited co-occurrence of Fusobacterium, Leptotrichia, and Campylobacter species (Pearson P < 0.01), which is strikingly similar to the microbial co-occurrence patterns observed on colorectal cancers (Warren et al., 2013). Increased abundance of the acetaldehydogenic microorganism Rothia mucilaginosa was also apparent on oral Leukoplakias from lingual sites (P 0.0012). Severe dysplasia was associated with elevated levels of Leptotrichia spp. and Campylobacter concisus (P < 0.05). Oral Leukoplakia exhibits an altered microbiota that has similarities to the microbiome of colorectal cancer
Joel B Epstein - One of the best experts on this subject based on the ideXlab platform.
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proliferative verrucous Leukoplakia and its progression to oral carcinoma report of three cases
Journal of Oral Pathology & Medicine, 2007Co-Authors: Thomas H Morton, Robert J Cabay, Joel B EpsteinAbstract:Proliferative verrucous Leukoplakia (PVL) is a distinct clinical form of oral Leukoplakia defined by its progressive clinical course, changing clinical and histopathologic features, and potential to develop into cancer. PVL behaves in a more aggressive and relentless manner than the more innocuous white oral lesions that it can resemble clinically. We present three cases of PVL that progressed to carcinoma and discuss the histopathologic findings that may either hinder or assist in the diagnosis.
Saman Warnakulasuriya - One of the best experts on this subject based on the ideXlab platform.
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malignant transformation of oral Leukoplakia a systematic review of observational studies
Journal of Oral Pathology & Medicine, 2016Co-Authors: Saman Warnakulasuriya, Anura AriyawardanaAbstract:The aim of this systematic review was to ascertain the malignant transformation rate of oral Leukoplakia and the associated risk factors. Method: Published literature was searched through several search engines from 1960 to the end of December 2013. The inclusion criteria included 'Leukoplakia', 'pre-cancer', 'malignant transformation', 'follow-up' and 'outcome'. Two reviewers extracted the data independently and also assessed the quality of evidence. Results: The search strategy resulted in 1032 abstracts or full-text articles, of which 24 met the inclusion criteria. There was much variation in the definitions used by the various authors in their original reports to define oral Leukoplakia or in the criteria used to recruit their patients for follow-up. The estimated overall (mean) malignant transformation rate for the total population described in these 24 studies amounts to 3.5% (405/11423), with a wide range between 0.13% and 34.0%. Based on the evidence presented, the features that stand out as significant determinants contributing to malignant potential of OL include advanced age, female sex, Leukoplakia exceeding 200 mm2, non-homogeneous type (eg. erythroLeukoplakia) and the higher grades of dysplasia. Conclusion: The review indicates that drawing meaningful evidence-based conclusions are difficult from retrospective studies of this nature. However, many of the determinants exposed in the review require further investigation by well-designed prospective studies.
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nomenclature and classification of potentially malignant disorders of the oral mucosa
Journal of Oral Pathology & Medicine, 2007Co-Authors: Saman Warnakulasuriya, Newell Walter Johnson, I Van Der WaalAbstract:At a workshop coordinated by the WHO Collaborating Centre for Oral Cancer and Precancer in the UK issues related to terminology, definitions and classification of oral precancer were discussed by an expert group. The consensus views of the Working Group are presented here. The term, ‘potentially malignant disorders’, was recommended to refer to precancer as it conveys that not all disorders described under this term may transform into cancer. Critically evaluating all definitions proposed so far for oral Leukoplakia, the Working Group agreed that the term Leukoplakia should be used to recognize ‘white plaques of questionable risk having excluded (other) known diseases or disorders that carry no increased risk for cancer’. An outline was proposed for diagnosing oral Leukoplakia that will prevent other oral white disorders being misclassified as Leukoplakia. The Working Group discussed the caveats involved in the current use of terminology and classification of oral potentially malignant disorders, deficiencies of these complex systems, and how they have evolved over the past several decades. The terminology presented in this report reflects our best understanding of multi-step carcinogenesis in the oral mucosa, and aspires to engender consistency in use.
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oral precancerous disorders associated with areca quid chewing smoking and alcohol drinking in southern taiwan
Journal of Oral Pathology & Medicine, 2005Co-Authors: Ching Hung Chung, Yihsin Yang, Tung Yiu Wang, Tien Yu Shieh, Saman WarnakulasuriyaAbstract:Objective: To investigate the prevalence and the associated risk factors of oral precancerous disorders in southern Taiwan. Methods: We conducted a cross-sectional community survey interviewing 1075 adult subjects, 15 years of age and over, gathered from randomly selected 591 households, and spanning five villages in southern Taiwan. The study protocol included a visual oral soft tissue examination and a questionnaire-based interview. The chi-square test was used to test the differences in prevalence of oral precancerous lesions and conditions by different ‘life styles’ relating to current risk habits of current areca quid chewing, smoking, and alcohol drinking. To control for possible confounding, a logistic regression model was used to estimate the Odds Ratios (OR) for Leukoplakia and oral submucous fibrosis (OSF). Results: 136 precancerous lesions and conditions were detected among 1075 subjects (12.7%). The analysis of the spectrum of oral precancerous disorders detected, Leukoplakia (n = 80), OSF (n = 17) and verrucous lesions (n = 9), demonstrated an association with gender (P < 0.001). There were statistically significant associations among Leukoplakia (P < 0.01), OSF (P < 0.0001), and verrucous lesions (P < 0.0001) and the life style of current areca quid chewing, smoking, and alcohol drinking. The synergistic effect of smoking and areca quid chewing habit on Leukoplakia and OSF was demonstrated. Conclusion: This study reinforces the association of current areca quid chewing without tobacco, cigarette smoking, and alcohol drinking to Leukoplakia, OSF, and verrucous lesions in Taiwan.
Sookbin Woo - One of the best experts on this subject based on the ideXlab platform.
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malignant transformation rate of non reactive oral hyperkeratoses suggests an early dysplastic phenotype
Head and Neck Pathology, 2021Co-Authors: Ivan J Stojanov, Sookbin WooAbstract:The presence of epithelial dysplasia (ED) in oral Leukoplakia is the single most important predictor of malignant transformation (MT). The majority of Leukoplakias, however, do not show evidence of ED and yet MT of these lesions is well-recognized. These lesions have been referred to as “hyperkeratosis/hyperplasia, no dysplasia,” “keratosis of unknown significance” and “hyperkeratosis, not reactive (HkNR).” This study evaluates the MT rate of such Leukoplakias. A literature review was performed to identify cohort studies on Leukoplakias where (1) there was a recorded histopathologic diagnosis, (2) cases of “hyperkeratosis/hyperplasia, no dysplasia” comprised part of the cohort, and (3) follow-up information was available. There were 9,358 Leukoplakias, of which 28.5% exhibited ED while 37.7% consisted of HkNR. Follow-up ranged from 15 to 73 months. The incidence of MT in Leukoplakia exhibiting HkNR was 4.9%, compared to 15.3% for ED. Among oral squamous cell carcinomas (SCC) with previously biopsied, site-specific precursor lesions, 55.7% arose from ED/carcinoma in situ and 28.0% arose from HkNR. Leukoplakia exhibiting HkNR has a substantial MT rate, similar to that of mild ED, and must be recognized and managed appropriately to reduce oral SCC incidence.
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Oral Epithelial Dysplasia and Premalignancy
Head and Neck Pathology, 2019Co-Authors: Sookbin WooAbstract:Leukoplakia and erythroplakia are two entities under the moniker of “oral potentially malignant disorders” that are highly associated with the presence of oral epithelial dysplasia (OED) at first biopsy, while lesions of submucous fibrosis develop OED after being present for years. Importantly, traumatic/frictional keratoses are often mistaken clinically for Leukoplakia and it is important for the pathologist to recognize and report them as such. The features of OED have been well-described and other architectural features will be discussed here, in particular verrucous and papillary architecture, bulky epithelial proliferation and epithelial atrophy. Proliferative Leukoplakia, verrucous or otherwise, often show only hyperkeratosis in early lesions, with development of OED occurring over time, and squamous cell carcinoma developing in the majority of cases over time. The concept of hyperkeratosis without features of OED and that is not reactive, is likely a precursor to the dysplastic phenotype. Many cases of Leukoplakia exhibiting OED are associated with a band of lymphocytes at the interface and these should not be mistaken for oral lichen planus.
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Leukoplakia a diagnostic and management algorithm
Journal of Oral and Maxillofacial Surgery, 2017Co-Authors: Alessandro Villa, Sookbin WooAbstract:Oral white lesions are frequently encountered in daily practice. Most white lesions are benign (eg, reactive keratoses or keratoses from inflammatory conditions) and the diagnosis is usually evident from the clinical presentation and histopathology. Leukoplakia is a common condition characterized by an increased risk for malignant transformation. Histopathology of Leukoplakia can disclose hyperkeratosis with dysplasia or carcinoma or hyperkeratosis or parakeratosis without dysplasia. Treatment depends on demographic, social, clinical, and histopathologic factors. This review focuses on the diagnosis and management of oral Leukoplakia.
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morsicatio mucosae oris a chronic oral frictional keratosis not a Leukoplakia
Journal of Oral and Maxillofacial Surgery, 2009Co-Authors: Sookbin Woo, Dorothy LinAbstract:Purpose Morsicatio mucosae oris (MMO) presents as white papules and plaques that may resemble Leukoplakia, and are often biopsied. The objective of this study is to document the clinical features and histopathology of MMO and to reevaluate the prevalence of dysplasia and/or cancer when this frictional keratosis is removed from the category of Leukoplakia. Materials and Methods Cases that were submitted to a single laboratory with a provisional diagnosis of “Leukoplakia,” “hyperkeratosis,” or “white lesion” were evaluated. Results Fifty-six lesions of MMO from 56 patients were identified out of 584 white lesions. Most cases occurred in the third to sixth decades of life. Thirty (53.6%) and 18 (32.1%) out of 56 lesions were located on the lateral tongue and buccal mucosa, respectively. The lesions showed hyperparakeratosis with a characteristic frayed, shaggy, peeling surface, and acanthosis with insignificant inflammation. When MMO is removed from the category of Leukoplakia, the percentage of true Leukoplakia that are dysplastic or malignant increased by 12.9%. Conclusions MMO is a form of chronic oral frictional keratosis that has no malignant potential, and should be signed out as such and not merely “hyperparakeratosis and acanthosis” so that it can be removed from the category of Leukoplakia where it does not belong.
