Proliferative verrucous leukoplakia of the gingiva

A Bibliometric and Visualised Analysis of Proliferative Verrucous Leucoplakia From 2003 to 2023

BACKGROUND

Proliferative verrucous leucoplakia (PVL) is a rare but slow-growing, aggressive leucoplakia lesion associated with the highest malignant transformation rate in oral potentially malignant disorders (OPMDs). With increasing attention paid to PVL, it is urgent for us to analyse and summarise the publications globally using comprehensive bibliometric studies to help researchers propose possible future research directions and guide them to further conduct relevant studies in the domain.

OBJECTIVES

The purpose of the study was to evaluate global academic productivity, impact, and collaboration of potentially malignant oral disorder PVL utilising bibliometrics based on annual number of publications, countries and regions, institution, authors, journals, citations and co-occurrences of author keywords over the last 20 years.

METHODS

This study searched publications pertaining to proliferative verrucous leucoplakia in the Web of Science Core Collection, spanning from 2003 to 2023. Utilizing VOSviewer, R software, Bibliometric online analysis platform, CiteSpace software, and Microsoft Excel, we conducted a bibliometric and visualised analysis of PVL.

RESULTS

The quantity of pertinent publications in this research domain displays a fluctuating but overall upward trend. In aggregate, there are 148 articles and 61 reviews, encompassing research contributions from 44 countries, 45 institutions, and involving 831 authors. Among these publications, the USA, Spain, and UK emerged as the predominant contributing nations. Predominantly, articles found their publication venue in "Pathology Research and Practice." Notably, the author with the highest number of publications and most influence is Warnakulasuriya S. The top 3 keywords include "Proliferative Verrucous Leucoplakia," "Squamous-Cell Carcinoma," "Oral Leucoplakia," and "Potentially Malignant Disorders."

CONCLUSION

In this investigation, statistical analysis and network visualisation were conducted to reveal the research progress, trends, and trending topics on PVL via a thorough bibliometric analysis. We found that current publications comprise mainly case reports, there is a significant research need to explore the molecular mechanisms, specific diagnostic criteria, and effective management options for PVL. Our work should serve as a key reference and a directional guide for future research in this domain.

Proliferative verrucous and homogeneous Leukoplakias exhibit differential methylation patterns

OBJECTIVE

Proliferative verrucous leukoplakia (PVL) is considered a clinically distinct entity from other oral leucoplakias (OLs) due to its clinical presentation and evolution. However, molecular differences between them remain unclear. We aimed to determine whether there are methylation differences between PVL and other forms of OLs.

MATERIALS AND METHODS

Oral biopsies from 12 patients with PVL, eight patients with homogeneous leucoplakia (HL), and 10 healthy individuals were obtained for a genome-wide DNA methylation analysis via the Infinium EPIC Platform.

RESULTS

A total of 1815 differentially methylated CpGs were found between PVL and HL, with a prominent state of hypermethylation in HL patients. CpGs covered 813 genes with distinct roles, including cell adhesion, extracellular matrix organization, and cell and synaptic signaling. 43% of these genes had been previously described in cancer and associated with prognosis. We developed a multinomial logistic regression model able to differentiate HL, PVL, and control samples. The model had a cross-validated estimate of 73% and included differentially methylated cancer-related genes between the pathological conditions and the healthy donors, including ADNP, BRCA2, CDK13, GNB1, NIN, NUMB, PIK3C2B, PTK2, SHISA4, THSD7B, WWP1, and ZNF292. It also included CpGs covering differentially methylated genes in HL (MEN1 and TNRC6B) and PVL (ACOXL, ADH1B, CAMTA1, CBFA2T3, CPXM2, LRFN2, SORCS2, and SPN).

CONCLUSIONS

PVL and HL present differential methylation patterns that could be linked to their differential clinical behavior. Our findings show the potential of methylation markers and suggest novel diagnostic biomarkers.

Proliferative Verrucous Leukoplakia Presenting as a Ring Around the Collar and Cancer: A Case Report

Proliferative verrucous leukoplakia (PVL) is an oral mucosa lesion with a high rate of malignant transformation. The diagnosis is often difficult, especially when the initial lesion is a simple homogeneous white leukoplakia, and when located only on the gingiva or palate. Moreover, the anatomopathological analysis is non-specific in the initial stages. The gingival PVL localisation (gPVL) is described as the most aggressive form with the highest rate of malignant transformation. Cases with a unique gingival localisation are rare, described with a "ring around the collar" clinical form. Considering the difficulty of early diagnosis of gPVL, we report the case of a 72-year-old woman, who presented "white lesions on her gingiva" with a slight discomfort in February 2019. The lesion was initially limited to the buccal part of the mandibular right gingiva, but rapidly extended to all the lingual and buccal mandibular gingiva during follow-up, leading to a diagnosis of gPVL. Two biopsies were performed, which concluded a verrucous hyperplasia and papilloma with a lichenoid part. The diagnosis of gPVL was made after a six-month follow-up based on clinical and anatomopathological factors. The gPVL transformed into a squamous cell carcinoma (SCC) after 18 months of follow-up. A surgical right mandibular bone excision with an autologous left fibula graft associated with radiotherapy was performed. Three years after the surgery, the patient remains under monitoring, with several gPVL and SCC recurrences treated. This case highlights that gPVL is a rare and aggressive form of PVL, with a high risk of fast malignant transformation. Knowledge about its aetiology, anatomic pathology, and biological markers is highly needed to speed up the diagnosis and develop specific follow-up and treatment.

Molecular landscape of proliferative verrucous leukoplakia: a systematic review

Proliferative verrucous leukoplakia (PVL) is a rare oral potentially malignant disorder characterised by multifocal origin and unpredictable long-term evolution to oral squamous cell carcinoma (OSCC) or oral verrucous carcinoma (OVC). Currently no predictive biomarkers are in clinical use. We aimed to explore the genomic profile of PVL. A total of 685 cases in 26 studies were included in this review. Genomic data were presented in 15% of studies and biomarker analysis was reported in 85% of studies. At first clinical presentation, PVL is characterised by a high loss of heterozygosity (LOH), similar to OSCC, and low copy number alterations (CNA). As these progress, more CNAs and mutations in CDKN2A and alterations to ELAVL1 expression are noted, but no TP53 mutations are identified. There is significantly lower LOH at 17p in early PVL compared with OSCC (p = 0.037). Deletions in chromosomal loci 17q12, 5q31.1 and amplifications in 7q11.2, 7q22 are shared between early lesions and OVC. PVL shows CNAs at 11q31. WNT signalling pathway genes (SUZ12, CTTN and FOLR3) are enriched in CN-altered regions. PVL stroma shows significantly lower α-SMA and higher CD34 expression than OVC and OSCC. The exact genomic landscape is currently unclear, and further studies are necessary to unravel this mystery.

Oral Squamous Papilloma Mimicking Oral Verrucous Leukoplakia

The human papillomavirus (HPV) is a non-enveloped DNA virus that causes a variety of skin and mucosal lesions. This report reviews a likely HPV-related lesion of oral squamous cell papilloma clinically mimicking oral verrucous leukoplakia. A 71-year-old white male presented with a raised white lesion on the palatal mucosa. It felt hard on palpation and had a sessile fixed base, and a rough verrucous surface. The lesion was fully excised. Histopathology showed short, thin, fingerlike projections lined by stratified squamous epithelium with thin central connective tissue cores. The epithelial superficial layers demonstrated focal koilocytotic changes suggestive of an HPV infection. High-risk HPV-related lesions have the potential to turn malignant. Early diagnosis and management are critical to preventing serious complications.

Prognostic outcomes of OSCC derived from proliferative verrucous leukoplakia: a systematic review

OBJECTIVE

This study aimed to evaluate prognostic outcomes of PVL-derived oral squamous cell carcinomas (P-OSCC) based on recurrence, new primary tumour, metastasis and survival information.

STUDY DESIGN

Five databases and grey literature were searched electronically with the following main keywords (proliferative verrucous leukoplakia, squamous cell carcinoma and malignant transformation) to answer the following review question: 'Are survival outcomes for P-OSCC worse?' based on the PECOS principle. The Joanna Briggs Institute Critical Appraisal tool was used to identify possible biases and assess the quality of each of the primary studies.

RESULTS

A total of 21 articles met the inclusion criteria, and the results of this systematic review suggest that P-OSCC can recur and generate new primary tumours; however, metastases are rare. Thus, most patients remain alive for an average period of 5 years.

CONCLUSION

Apparently, P-OSCC has better clinical prognostic characteristics than conventional OSCC. There is a lack of information on the main prognostic outcomes of P-OSCC; therefore, specific studies must be performed to achieve a better comparison between P-OSCC and conventional OSCC progression.

Malignant development of proliferative verrucous/multifocal leukoplakia: A critical systematic review, meta-analysis and proposal of diagnostic criteria

BACKGROUND

Proliferative verrucous/multifocal leukoplakia (PVML) is an oral potentially malignant disorder (OPMD) that exhibits high rates of malignant development (MD). This study aimed to analyse the risk of MD of PVML, as well as to investigate the possible risk factors associated with its malignization.

METHODS

A bibliographical search of the PubMed, Embase, Web of Science, and Scopus databases was conducted. PVML MD rates were calculated as a pooled proportion, and the risk factors were calculated as risk ratios, using fixed and random models based on the presence of heterogeneity.

RESULTS

From a total of 417 records, 16 articles were retrieved for inclusion. The subgroup analysis revealed a higher MD rate in the studies that were conducted in America, and, likewise, said studies involved a longer follow-up time (>6 years). There was a non-significant lower risk of malignization among males. A negative correlation was observed between MD and the year in which the studies were published.

CONCLUSIONS

The pooled MD of PVML was 65.8% (95% CI: 55.3-76.2, p < 0.001). Prospective studies of PVML must be designed using simple and universal clinical diagnostic criteria to be able to make an early diagnosis of this important OPMD and acknowledge the frequency of MD.

Prognosis Parameters of Oral Carcinomas Developed in Proliferative Verrucous Leukoplakia: A Systematic Review and Meta-Analysis

Simple Summary

Proliferative verrucous leukoplakia is considered by the WHO as an oral potentially malignant disorder that presents the highest tendency to recurrence and malignant transformation rate. However, to date limited evidence-based prognostic data for oral carcinomas developed in patients with proliferative verrucous leukoplakia (PVL-OC) have been published, and these carcinomas probably perform better than conventional oral carcinomas. In this study we present a systematic review and meta-analysis to evaluate the current evidence in relation to the prognosis of oral carcinomas developed in patients PVL-OC.

Abstract

Proliferative verrucous leukoplakia (PVL) is contemplated by the World Health Organization (WHO) as an oral potentially malignant disorder (OPMD) with a high the highest malignant transformation ratio among all OPMD (approximately 50%). Our aim was to evaluate the current evidence in relation to the prognosis of oral carcinoma developed in patients with proliferative verrucous leukoplakia (PVL-OC). We searched PubMed, Embase, Web of Science and Scopus for published studies (upper date limit = June 2021). We evaluated the quality of studies (QUIPS tool). We carried out meta-analyses, examined inter-study heterogeneity through subgroup and meta-regression analyses, and performed sensitivity and small-study effects analyses to test the stability and reliability of results. 23 studies met inclusion criteria (505 patients with PVL, of which 288 developed a total of 504 carcinomas). The meta-analyzed overall mortality rate was 21.29% (pooled proportions [PP] = 95% confidence intervals [CI] = 8.77–36.36) for PVL-OC, clearly lower than the 34.7–50% mortality rate for conventional oral cancer reported in previous studies. In comparison with a single study reporting on conventional oral cancers, mortality was significantly lower for PVL-OC (hazard ratio = 0.29 [95%CI = 0.10–0.89], p = 0.03). Univariable meta-regression verified that case series that presented higher proportions of verrucous carcinomas showed a better survival of PVL-OC (p = 0.05), but not with higher proportion of oral squamous cell carcinomas (p = 0.74). Significant differences were not found for other relevant variables such as follow up period (p = 0.44) or multiple tumor development (p = 0.74). In conclusion, PVL-OC show favorable prognostic parameters, especially with regard to the mortality rate.

Oral Proliferative Verrucous Leukoplakia: Progression to Malignancy and Clinical Implications. Systematic Review and Meta-Analysis

Simple Summary

Proliferative verrucous leukoplakia (PVL) was recognized in 2005 by the World Health Organization as a rare subtype of true oral leukoplakia, with unknown etiology. Since its first description in 1985, several diagnostic criteria have been proposed over the years. The aim of this systematic review is to investigate the percentage of patients diagnosed with proliferative verrucous leukoplakia who progressed to oral verrucous carcinoma (OVC) or conventional oral squamous cell carcinoma (OSCC).

Abstract

Aim: The aim of the present systematic review was to investigate the risk of malignant transformation of proliferative verrucous leukoplakia (PVL). Materials and Methods: the search was carried out using a combination of terms (leukoplakia OR leucoplakia) AND (multifocal OR proliferative) on the following databases: PubMed, Scopus, Web of Science (WOS Core Collection), Cochrane Library, selecting only articles published since 1985 and in the English language. Demographic, disease-related, and follow-up data extracted from the studies included in the qualitative synthesis were combined. Weighted means ± standard deviations were calculated for continuous variables, while categorical variables were reported as frequencies and percentages. Dichotomous outcomes were expressed as odd ratios (ORs) with 95% confidence intervals (CIs). Odd ratios for individual studies were combined using a random-effects meta-analysis, conducted using Review Manager 5.4 Software (Cochrane Community, Oxford, England). Results: twenty-two articles were included, with a total of 699 PVL patients, undergoing a mean follow-up of 7.2 years. Sixty-six percent of patients were females, with a mean age of 70.2 years, and 33.3% were males, with a mean age of 59.6 years. Most patients were non-smokers and non-alcohol users, and the gingiva/alveolar ridge mucosa was the most involved anatomical site by both PVL appearance and malignant transformation. A total of 320 PVL patients developed oral verrucous carcinoma (OVC) or conventional oral squamous cell carcinoma (OSCC) because of malignant transformation of PVL lesions (45.8%). A statistically significant 3.8-fold higher risk of progression to conventional OSCC was found compared to OVC in PVL patients, with women being 1.7 times more likely to develop oral cancer than men, as a consequence of PVL progression. Moreover, a statistically significant higher likelihood of developing conventional OSCC in female PVL patients than in males was found. In 46.5% of patients with PVL malignant transformation, multiple carcinomas, in different oral sites, occurred during follow-up. Conclusions: PVL is an aggressive lesion, which, in a high percentage of cases (almost 50%), undergoes malignant transformation, mainly toward OSCC. The female gender is most affected, especially in the elderly, with a negative history for alcohol and tobacco consumption.

Oral microbiome in Proliferative Verrucous Leukoplakia exhibits loss of diversity and enrichment of pathogens

OBJECTIVES

Oral microbiome plays an important role in oral diseases. Among them, proliferative verrucous leucoplakia (PVL) is an uncommon form of progressive multifocal leukoplakia with a worryingly rate of malignant transformation. Here, we aimed to characterize the oral microbiome of PVL patients and compare it with those of healthy controls.

MATERIAL AND METHODS

Oral biopsies from ten PVL patients and five healthy individuals were obtained and used to compare their microbial communities. The sequence of the V3-V4 region of 16S rRNA gene was used as the taxonomic basis to estimate and analyze the composition and diversity of bacterial populations present in the samples.

RESULTS

Our results show that the oral microbial composition and diversity are significantly different among PVL patients and healthy donors. The average number of observed operational taxonomic units (OTUs) was higher for healthy donors than for PVL, proving a loss of diversity in PVL. Several OTUs were found to be more abundant in either group. Among those that were significantly enriched in PVL patients, potential protumorigenic pathogens like Oribacterium sp. oral taxon 108, Campylobacter jejuni, uncultured Eubacterium sp., Tannerella, and Porphyromonas were identified.

CONCLUSION

Oral microbiome dysbiosis was found in patients suffering from PVL. To the best of our knowledge, this is the first study investigating the oral microbiome alterations in PVL and, due to the limited number of participants, additional studies are needed. Oral microbiota-based biomarkers may be helpful in predicting the risks for the development of PVL.

Malignant transformation of oral proliferative verrucous leukoplakia: A systematic review and meta-analysis

OBJECTIVES

To investigate the available evidence on the malignant transformation (MT) of oral proliferative verrucous leukoplakia (PVL).

MATERIAL AND METHODS

We searched six main electronic and three grey literature databases in a two-phase process. Cohort studies investigating MT of PVL were eligible for inclusion. The risk of bias (RoB) was assessed using a specific tool developed by the Joanna Briggs Institute. Proportion meta-analyses were performed using a random-effects model.

RESULTS

Study selection resulted in the inclusion of 17 studies. The pooled proportion of MT was 43.87% (95% CI = 31.93-56.13). Females (64.02%, 95% CI = 54.87-72.75) were more affected by PVL than males (35.98%, 95% CI = 27.25-45.13). Gingiva (39.6%) and buccal mucosa (21.6%) were the most frequent PVL sites. No conclusive results were found between MT and sex or age distribution, tobacco, or alcohol consumption. Gingiva was the most common site for MT (39.9%), and the most frequent histopathological subtype was conventional squamous cell carcinoma (62.1%). Four studies were classified as low, nine as moderate, and four as high RoB.

CONCLUSION

The MT pooled proportion was 43.87%. Among OPMDs, PVL has the highest risk to transform to malignancy. Development and agreement on diagnostic criteria for PVL would reduce the heterogeneity among future studies.

Recurrences following treatment of proliferative verrucous leukoplakia: A systematic review and meta-analysis

BACKGROUND

A systematic review and meta-analysis were made of the incidence of recurrences in patients with proliferative verrucous leukoplakia (PVL) subjected to different types of treatment.

METHODS

The study was carried out following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement guidelines. A literature search was made in the Medline (PubMed), EMBASE, and Web of Science databases, together with a manual search, covering the period from 1985 to January 2020, with no language restrictions. Studies were included if they described treatments applied to at least 10 patients with the corresponding outcomes. Methodological quality was evaluated using Jadad scale and Newcastle-Ottawa tool. Global incidence was calculated by random effects meta-analysis using the Comprehensive Meta-analysis version 3.0 software. Publication bias was assessed using funnel plots and the Duval and Tweedie trim and fill method.

RESULTS

Of the 922 identified articles, 12 were found to meet the inclusion criteria. Most of them presented moderate or low risk of bias. A total of 397 patients were analyzed. The mean age was 62.34 years and 248 were women (62.5%). The mean follow-up was 79.3 months. The most frequent treatment was surgical removal with a cold scalpel or laser (339 patients). A total of 232 subjects presented lesion recurrence. The combination of proportions global effect meta-analysis yielded a recurrence rate of 67.2% (95% CI: 48.3-81.8), with the absence of publication bias.

CONCLUSIONS

There is not enough scientific evidence to conclude that any treatment strategy is able to reduce the recurrence in PVL.

Molecular, genomic and mutational landscape of oral leukoplakia

Oral leukoplakia (OLK) and its more aggressive clinical variant proliferative verrucous leukoplakia (PVL) remain enigmatic disorders clinically and histopathologically. Despite decades of research into both, there has been only incremental advancement in our understanding of their aetiology and pathogenesis and only minimal improvement in effective management strategies. Currently, no specific prognostic genetic or molecular marker has been reported for leukoplakia. There is, however, an emerging body of evidence characterising the genomic and transcriptomic profile of OLK. Regardless of the significance of cellular and architectural features of OLK and PVL, it is clear from studies reported in this review that new emerging evidence points to the presence of premalignant molecular subtypes of leukoplakia which require further investigation. This up-to-date review explores the contemporary genomic, transcriptomic and mutational landscape of leukoplakia broadly, discusses concepts that may not be widely recognised or accepted and purposefully highlights studies with juxtaposed findings in an effort to challenge dogma. It also highlights the urgent need for a concerted international effort of original collaborative research which will only occur by pooling collective efforts, resources and intellect to define the molecular fingerprint of this enigmatic disorder, in the hope it will better inform diagnosis, stratification and treatment.

Association of Human Papillomavirus With Oral Lichen Planus and Oral Leukoplakia: A Meta-analysis

OBJECTIVES

To estimate the association of human papillomavirus (HPV) infection with oral lichen planus (OLP) and oral leukoplakia (OLK), and determine risk cofactors.

STUDY DESIGN

Seven databases were searched for case-control or cross-sectional studies of OLP and OLK with healthy controls, published between 1976 and 2020. The Meta package of R software was applied to calculate the pooled odds ratios (OR) and 95% confidence interval (CI).

RESULTS

Thirty-six articles were finally included. OLP and OLK cases had a higher association with HPV infection than controls (OLP: OR: 4.91, 95% CI: 2.76-8.72; OLK: OR: 2.51, 95% CI: 1.55-4.07). In subgroup analyses, the OR of HPV infection was higher with erosive lesions than with nonerosive lesions (OLP: OR: 5.36 and 3.47, respectively; OLK: OR: 3.34 and 3.21, respectively). Oral lesions were more strongly associated with HPV16/18 than with HPV6/11 (OLP: OR: 7.84 and 1.42, respectively; OLK: OR: 6.05 and 1.87, respectively) and varied by geographic region (OLP: OR: 4.01-7.02; OLK: OR: 1.46-27.13).

CONCLUSIONS

Oral HPV infection, particularly infection with HPV 16/18, was strongly associated with OLP and OLK. Risk cofactors included erosive lesions and geographic region.

Marginal linear gingival leukoplakia progressing to "ring around the collar"-An ominous sign of proliferative verrucous leukoplakia

BACKGROUND

Potentially malignant lesions of the gingiva may frequently present as well-demarcated white lesions confined to the marginal gingiva. These lesions often become thick and verrucoid and spread along the marginal gingiva to encircle the tooth. Some cases of marginal gingival leukoplakia, over time, progress to extensively involve the gingiva fulfilling the criteria for proliferative verrucous leukoplakia (PVL). The objective of this study is to raise awareness of this pattern of leukoplakia by reporting a series of cases of marginal gingival leukoplakia.

METHODS

An Institutional Review Board approved retrospective search of University of Florida and University of Nebraska Medical Center oral biopsy services was performed for all gingival biopsies. Inclusion criteria included cases exhibiting marginal gingival leukoplakia, and with accompanying clinical images.

RESULTS

A total of 30 cases of marginal gingival leukoplakia were included. All cases presented as well-demarcated leukoplakias, either on the buccal or lingual gingival margin, or circumferentially forming a "ring around the collar" of single or multiple teeth. Eight patients had recurrent lesions and 12 had multifocal involvement. Six of the 12 patients with multifocal involvement presented with a "ring around the collar." The histopathologic diagnoses were representative of benign lesions in seven cases, premalignant in 13, and malignant or suggestive of malignancy in 10 cases. Seven patients had carcinoma at the time of first biopsy, whereas 6 cases showed progression at time of follow-up.

CONCLUSION

This study aims to raise awareness that marginal gingival leukoplakia may represent potentially malignant lesions, and if circumferential and/or thick, may be the first manifestation of PVL.

World Workshop on Oral Medicine VII: Prognostic biomarkers in oral leukoplakia and proliferative verrucous leukoplakia-A systematic review of retrospective studies

OBJECTIVE

To systematically review retrospective studies examining prognostic potentials of candidate biomarkers to stratify malignant progression of oral leukoplakia (OL) and proliferative verrucous leukoplakia (PVL).

MATERIALS AND METHODS

A systematic literature search of PubMed, EMBASE, Evidence-Based Medicine and Web of Science databases targeted literature published through 29 March 2018. Inter-rater agreement was ascertained during title, abstract and full-text reviews. Eligibility evaluation and data abstraction from eligible studies were guided by predefined PICO questions and bias assessment by the Quality in Prognosis Studies tool. Reporting followed Preferred Reporting Items for Systematic Review and Meta-Analysis criteria. Biomarkers were stratified based on cancer hallmarks.

RESULTS

Eligible studies (n = 54/3,415) evaluated 109 unique biomarkers in tissue specimens from 2,762 cases (2,713 OL, 49 PVL). No biomarker achieved benchmarks for clinical application to detect malignant transformation. Inter-rater reliability was high, but 65% of included studies had high "Study Confounding" bias risk.

CONCLUSION

There was no evidence to support translation of candidate biomarkers predictive of malignant transformation of OL and PVL. Systematically designed, large, optimally controlled, collaborative, prospective and longitudinal studies with a priori-specified methods to identify, recruit, prospectively follow and test for malignant transformation are needed to enhance feasibility of prognostic biomarkers predicting malignant OL or PVL transformation.

Potentially malignant disorders of the oral cavity and oral dysplasia: A systematic review and meta-analysis of malignant transformation rate by subtype

IMPORTANCE

Potentially malignant disorders of the oral cavity (OPMD) are a heterogeneous group of lesions associated with a variable risk of malignant transformation (MT) to invasive cancer. Leukoplakia (LE), lichen planus (LP), oral lichenoid lesions (OLL), oral erythroplakia (OE), oral submucous fibrosis (OSF), and proliferative verrucous leukoplakia (PVL) are among the most common of these lesions. Oral dysplasia is a mucosal area characterized by cellular and architectural derangement, which may be associated with OPMDs or not.

OBJECTIVE

To define the MT rate of OPMDs and the risk of development into cancer of mild vs moderate/severe oral dysplasia. This in order to implement adequate follow-up strategies and treatment decisions.

STUDY DESIGN

We performed a systematic review and meta-analysis on studies reporting the MT rates of OPMDs and oral dysplasia. Ninety-two studies were included for the analysis. Cumulative rates were reported for OPMDs overall and as a subgroup, a comparison was made of mild vs moderate/severe dysplasia. Meta-regression on OPMD and year of publication was also performed.

MAIN OUTCOME AND MEASURES

Overall MT rates of OPMDs and odds ratio of MT of mild vs moderate/severe dysplasia.

RESULTS

Overall MT rate across all OPMD groups was 7.9% (99% confidence interval [CI] 4.9%-11.5%). MT rates of the specific OPMD subgroups were as follows: LP 1.4% (99% CI 0.9%-1.9%), LE 9.5 (5.9%-14.00%), OLL 3.8% (99% CI 1.6%-7.00%), OSF 5.2% (99% CI 2.9%-8.00%), OE 33.1% (99% CI 13.6%-56.1%), and PVL 49.5% (99% CI 26.7%-72.4%). Regarding the dysplasia grades comparison, the meta-analysis showed that moderate/severe dysplasia is meaningfully associated to a much greater risk of MT compared to mild dysplasia with an odds ratio of 2.4 (95% CI 1.5-3.8) [Correction added on 27 December 2019, after first online publication: CI updated from 99% to 95%.]. Heterogeneity was not significant. Annual MT rates were approximated based on the average follow-up as reported in the various subgroups. Lichen planus had an annual MT of 0.28%, OLL of 0.57%, leukoplakia of 1.56%, PVL of 9.3%, and OSF of 0.98%. Mild dysplasia had an annual MT of 1.7%, while severe dysplasia of 3.57%. Meta-regression showed a significant negative correlation of PVL MT rate and year of the study (P value <.001).

CONCLUSIONS AND RELEVANCE

OPMDs and oral dysplasia are relatively common conditions that general practitioners, head and neck, and oral medicine specialists, face in their everyday practice. Our analysis confirms the significant risk of MT of these lesions, although variable among the subgroups. Moderate/severe dysplasia bears a much higher risk of cancer evolution than mild dysplasia. It is important to raise public health awareness on the MT rates of these conditions, at the same time efficacious communication with the patient is of utmost importance. This, coupled with strict follow-up measures and optimal treatment strategies, would help in reducing the transformation of these oral conditions into invasive cancer.

Clinicopathologic analysis of verrucous hyperplasia, verrucous carcinoma and squamous cell carcinoma as part of the clinicopathologic spectrum of oral proliferative verrucous leukoplakia: A literature review and analysis

OBJECTIVE

Proliferative verrucous leukoplakia is classified as a potentially malignant disorder because of its high rate of malignant transformation. PVL progresses in a series of clinical stages where the early stage represents multiple, multifocal leukoplakias with a high recurrence rate. The intermediate and late stages are clinically exophytic lesion, diagnosed microscopically as verrucous hyperplasia that often progresses into verrucous carcinoma and/or squamous cell carcinoma. There is no single histologic definition and the diagnosis is retrospective following observed progression of the disorder. The goal of the current study was to conduct a literature review and analysis of PVL in the later stages to gain further knowledge on their clinicopathologic features.

DATA SOURCES

Medline's PubMed and Google Scholar were searched for adequately documented cases from 1985 to 2018. References of published articles were searched for additional cases.

REVIEW METHODS

Overall, 57 manuscripts were analyzed. 35/57 manuscripts provided adequate data on the clinicopathologic features in the premalignant and malignant stages.

RESULTS

Malignant transformation rate was 50% (average of 57 months). Gingiva, palate and buccal mucosa were the most common locations. Clinicopathologic features included; well differentiated carcinoma (78%), perineural invasion (3%), lymph node metastasis (4%); distant metastasis (0%), average duration of illness (65 months), DOD-dead of disease (44%). Moderate dysplasia, severe dysplasia and carcinoma in situ were exceptionally uncommon in the premalignant stages (0.8%).

CONCLUSION

Prognostic factors such as perineural invasion, lymph node metastasis and distant metastasis were uncommon occurrences which may have practical implications on treatment. Further studies are needed to substantiate our findings.

Second primary tumors in proliferative verrucous leukoplakia: a series of 33 cases

OBJECTIVES

To describe the number of second primary malignancies in a series of 33 patients with proliferative verrucous leukoplakia (PVL), detailing the mean time between primary malignancies and their clinical characteristics.

MATERIALS AND METHODS

Two groups of patients were included in this study: group 1 comprised 33 PVL patients who had developed ≥ 2 oral squamous cell carcinoma (OSCC) and group 2 comprised 48 PVL patients without malignant degeneration. We compared the groups with regard to age, gender, oral location, and number of oral sites affected. For patients in group 1, we determined the locations, clinical forms, and TNM stages of oral cancers. We also recorded the intervals of time between instances of oral cancer for all patients.

RESULTS

The groups did not differ significantly in age; however, group 1 included more women (p < 0.05). The follow-up period and number of oral PVL locations were greater in group 1 (p < 0.01). Moreover, in group 1, as the number of OSCCs increased, the intervals between them became shorter. The gingiva was the most common site. The mean number of cancers in group 1 was 3.15; five second primary tumors were diagnosed in one patient.

CONCLUSIONS

Multiple cancers in PVL patients were more frequently located on the gingiva in the form of erythroleukoplastic areas. In addition, the interval between new cancers decreased over time.

CLINICAL RELEVANCE

This is the series with the highest number of cases described with second primary tumors in PVL.

A Retrospective 20-Year Analysis of Proliferative Verrucous Leukoplakia and Its Progression to Malignancy and Association with High-risk Human Papillomavirus

Proliferative verrucous leukoplakia (PVL) is defined as an aggressive, relentless and recalcitrant form of leukoplakia that has a high propensity for malignant transformation. The aim of this study was to evaluate the malignant potential of PVL and determine its possible association with high-risk human papillomavirus (HPV). Twenty cases with a clinical and biopsy proven diagnosis of PVL were collected from the University of Florida Oral Medicine clinic database. Immunohistochemistry was performed to evaluate the expression of p16INK4A and p53 genes in the PVL lesions. The lesions were also tested for high-risk HPV by DNA in-situ hybridization. The average age of the patients at the time of first biopsy was 62.7 years. Most patients had multiple sites of involvement, gingiva being the most common location. The lesions progressed to malignancy in approximately 50% of patients. The expression of p16INK4A gene was considered negative, with at least a 50-65% immunoreactivity observed in only three cases that progressed to malignancy. No expression of high-risk HPV was detected, whereas p53 staining was positive in less than 25% of the cells demonstrating gene expression. No definite association between PVL and high-risk HPV infection could be established. Due to the high transformation potential of PVL, early recognition with aggressive treatment, including multiple biopsies, and continued close clinical follow-up, remain the mainstay of favorable management of this condition.

Proliferative leukoplakia: Proposed new clinical diagnostic criteria

OBJECTIVE

We aimed to characterize proliferative verrucous leukoplakia (PVL) from a clinical and histopathological standpoint and suggest an updated classification.

SUBJECTS AND METHODS

Records of patients seen at three oral medicine centers with a clinical diagnosis of PVL were reviewed for clinical and histopathological features and malignant transformation (MT).

RESULTS

There were 42 patients (median age: 69 years [range: 36-88]; 35 females). 12.2% were current smokers. Family history of cancer was present in 43.7% of patients. Partial demarcation of lesion margins was present in 31.3% of lesions, followed by verrucous (27.5%), smooth (22.7%) erythematous (22.3%), and fissured (18.3%) appearance. Large and contiguous and multisite and non-contiguous lesions comprised 57.1% (24/42) and 35.7% (15/42) of PVL cases, respectively. 19.1% had prominent erythema (erythroleukoplakia). The most common histopathological diagnosis at first visit was hyperkeratosis without dysplasia (22/42; 56.4%). MT occurred in 71.4% patients after a median of 37 months [range: 1-210] from initial visit; erythroleukoplakia exhibited MT in 100% of cases.

CONCLUSION

The generic term "proliferative leukoplakia (PL)" may be more appropriate than PVL because 18.3% were fissured and 22.7% erythematous. We also propose the term proliferative erythroleukoplakia to more accurately describe the subset of PL with prominent erythema, which had the highest MT rate.

Proliferative verrucous leukoplakia misdiagnosed as oral leukoplakia

Correct diagnosis of white lesions of the oral cavity is sometimes difficult, because some oral white lesions behave differently and tend to change their appearance with time. Clinicians often wrongly diagnose such lesions as oral leukoplakias and treat simply. Lesions recur and turn malignant. Proliferative verrucous leukoplakia (PVL) is a distinct form of oral leukoplakia characterized by a high recurrence rate and high rate of transformation into oral squamous cell carcinoma. We present herein a case of PVL which was misdiagnosed as oral leukoplakia and progressed to oral carcinoma.

Proliferative verrucous leukoplakia: diagnosis, management and current advances

Introduction

Proliferative verrucous leukoplakia is a multifocal and progressive lesion of the oral mucosa, with unknown etiology, and commonly resistant to all therapy attempts with frequent recurrences. It is characterized by a high rate of oral squamous cell carcinoma and verrucou carcinoma transformations.

Objective

To analyze the studies about Proliferative verrucous leukoplakia and develop a concise update.

Methods

A Pubmed search identifying studies (laboratory research, case series and reviews of literature) that examined patients with Proliferative verrucous leukoplakia was realized.

Results

There are not enough studies about Proliferative verrucous leukoplakia in the literature. The few found studies not present a consensus about its etiology and diagnosis criteria. Although several treatment strategies have been proposed, most of them still show a high recurrence rate.

Conclusion

More research about Proliferative verrucous leukoplakia is necessary to understand and treat this disease.

Low expression of angiotensinogen and dipeptidyl peptidase 1 in saliva of patients with proliferative verrucous leukoplakia

AIM

To elucidate the profile of the salivary proteome.

METHODS

Unstimulated whole mouth saliva was collected from 30 volunteers [15 proliferative verrucous leukoplakia (PVL) patients and 15 controls] and proteins were submitted for mass spectrometry-based proteomics using the discovery approach, followed by analyses of variance and logistic regression tests.

RESULTS

A total of two hundred and eighty-three proteins were confidently identified in saliva. By combining two low abundance proteins from the PVL group, angiotensinogen (AGT) and dipeptidyl peptidase 1 (DPP1), a model for group differentiation was built with a concordance index of 94.2%, identifying both proteins as potential etiologic biomarkers for PVL.

CONCLUSION

This study suggests that both AGT and DPP1 may be involved in developmental mechanisms of PVL.

Elucidating risk factors for oral leukoplakia affecting gingivae in Japanese subjects

Background:

Clinicopathological studies have revealed some distinct anatomical variations in the clinical presentation of oral leukoplakia (OL). Screening studies have shown that gingival leukoplakia (GL) to be more common among the Japanese.

Objective:

A hospital-based case-control study was undertaken among patients diagnosed with OL to compare clinico-pathological data between GL and OL affecting other sites (n-GL).

Methods:

One hundred fifty-one subjects attending four city hospitals in Japan diagnosed with OL were recruited to this study. OL was diagnosed by World Health Organization criteria. They were interviewed for risk factors, clinical presentations were charted and investigated by patch testing for allergy to dental materials and by biopsy for dysplasia.

Results:

Eighty-eight with GL and 63 with n-GL were included in the study. GL lesions were predominantly white (93%) though n-GL leukoplakia had red (speckled) foci in 26%. Eighty percent of GL were seen in association with prosthesis or restorations. There were no significant differences by age or in tobacco and alcohol use in the two groups. Metal allergy test was positive in 58% of the GL but was not significantly higher compared to the n-GL (41%). Histopathological features showed that inflammatory cell infiltrate was predominant in n-GL group ( p = 0.021). Higher dysplasia grades were also found in n-GL ( p = 0.018). During follow-up, nine oral cancers (14%) were detected in n-GL group and among GL cases four developed oral carcinomas (5%) ( p = 0.043). Cox hazard regression analysis revealed that after adjusting for age and sex, GL group was found to have a lower malignant risk, with a hazard ratio of 0.89 (95% CI: 0.51–1.04) when compared to n-GL.

Conclusions:

GL was more benign compared to n-GL in Japanese subjects, though risk factors appear similar. Further study is warranted to ascertain whether trauma may play an important role for hyperkeratinization of gingival tissues and possible evolution of GL to proliferative verrucous leukoplakia in later years.

Evaluation of different diagnostic criteria of diseases manifesting the oral cavity - A review. Part-1

There are many disorders affecting the oral cavity, which can cause difficulty in diagnosis for an oral physician. A criterion is defined as 'a principle or standard by which something may be judged or decided'. Several criteria have been given by different authors or committee, which further aids in diagnosis of certain disease. This article encompasses a collection and analysis of all the criteria of diseases affecting the oral cavity, which will be beneficial for an oral physician in their routine clinics.

[Proliferative verrucous leukoplakia: Three cases and literature review]

BACKGROUND

The aim of this study was to collect epidemiological, aetiopathogenic, clinical, histological and therapeutic data concerning proliferative verrucous leucoplakia (PVL) and to report three new cases.

PATIENTS AND METHODS

A literature review performed using the Medline database enabled us to collate 39 studies involving 607 cases. Three new cases were added.

RESULTS

PVL is a rare disease characterized by extensive and multifocal oral leucoplakic lesions. Its histological pattern depends on the stage of the disease: hyperkeratosis, verrucous hyperplasia, verrucous carcinoma and squamous cell carcinoma. The aetiopathogenesis of PVL is poorly understood and there is no clear consensus concerning therapy. Malignant transformation occurs in over 50 % of cases.

DISCUSSION

Diagnosis of PVL is difficult because of the presenting signs, which can be mistaken for those of other diseases. Management may be complicated and long-term follow-up is essential.

Optimal Management of Proliferative Verrucous Leukoplakia

Objective

Proliferative verrucous leukoplakia (PVL) is a rare and recalcitrant form of leukoplakia. The purpose of this review is to further characterize the risk factors, clinical course, and optimal treatment for this highly aggressive, premalignant lesion.

Data Sources

Twenty-six articles on PVL with a total of 329 PVL cases.

Review Methods

A systematic review of the literature using Ovid, PubMed, Cochrane Database, and gray literature was conducted of all PVL cases reported between 1985 and 2014. Inclusion criteria required reporting of patient follow-up and recurrence rates. Data were analyzed using descriptive statistics. Student t test and Fisher exact test were used to identify factors associated with malignant transformation.

Results

The mean patient age was 63.9 years. Most patients were female (66.9%) and nontobacco users (65.22%). Mean follow-up was 7.4 years, with an average of 9.0 biopsies per patient during this period. Proliferative verrucous leukoplakia exhibited histopathologic features along a progressive spectrum, evolving from leukoplakia to verrucous hyperplasia and ultimately invasive carcinoma. Surgery was the most common treatment implemented, but recurrence rates among 222 patients reached 71.2%. Subgroup analysis of 277 patients identified a 63.9% malignant transformation rate, and 39.6% of patients died of their disease. Age, sex, and tobacco use were not identified as risk factors associated with progression to cancer.

Conclusions

Proliferative verrucous leukoplakia is a rare form of leukoplakia with a high rate of malignant transformation. It necessitates high clinical suspicion, to include a lifetime of close follow-up and repeat biopsies by a health care provider well versed in oral carcinoma.

Oral proliferative verrucous leucoplakia: are there particular features for such an ambiguous entity? A systematic review

Proliferative verrucous leucoplakia (PVL) is a distinct, particularly aggressive form of oral leucoplakia. Given the low prevalence of PVL, data are sparse and are mostly from case reports, case series and only a few case-control studies, meaning that the literature is able to provide only weak evidence. The present systematic literature review aims to collate the available evidence on the following issues: patient demographics, aetiology, lesion location(s), malignant potential, location and histopathological features of transformed lesions, disease-specific survival rates and treatment response. Electronic databases were searched for studies in the English language reporting original data from at least 10 patients with PVL on the target issues of the present review. The retrieved data were merged and a descriptive analysis performed. The 20 studies selected indicated that PVL does not seem to be correlated with the major risk factors for oral carcinoma (tobacco, alcohol and/or areca nut/betel leaf chewing). The disorder affects mainly adult/elderly women and has a very high malignant transformation rate, particular site distribution and particular location and histopathological features of transformed lesions. The present results may be limited by some articles being unintentionally excluded as they were not found during the electronic search, a lack of worldwide accepted diagnostic criteria for PVL, and overlapping data from multiple studies performed in a limited number of centres. Despite these potential drawbacks, the present results demonstrate that PVL does have particular features.

Oral squamous cell carcinoma associated with proliferative verrucous leukoplakia compared with conventional squamous cell carcinoma--a clinical, histologic and immunohistochemical study

OBJECTIVE

Proliferative verrucous leukoplakia (PVL), a potentially malignant disorder, often undergoes malignant transformation to oral squamous cell carcinoma. The aim of our study was to document and compare the histologic, immunohistochemical, and clinical features and the survival rates of carcinoma arising in patients with PVL (p-scca) with conventional squamous cell carcinoma (c-scca) in order to determine if p-scca should be categorized as a separate clinical entity.

MATERIALS AND METHODS

A retrospective review of 11 patients with PVL, 38 with p-scca tumors and 49 with c-scca tumors: buccal mucosa (n = 28) and gingiva or palate (n = 21). Immunohistochemistry was performed by using antibodies directed against p16, p53, and ki67.

RESULTS

P-scca had lower clinical stage (P = .0001), smaller tumor size (P = .0033), no lymph node metastasis (P = .0002) or distant metastasis (P = .05), and better short term (P = .03), but not long term (P = .12) survival. Microscopically, p-scca tumor thickness was significantly less (P = .0001). P-53 overexpression was more common in p-scca (P = .0043) but not ki67 or p16 overexpression.

CONCLUSIONS

P-scca, compared with c-scca, presented with significantly better prognostic factors and short-term survival rates and longer duration of disease. Our results suggest that p-scca may represent a distinct entity, which may have practical implications when deciding on treatment. Further studies on a larger cohort of patients are recommended.

Retrospective case-control study of viral pathogen screening in proliferative verrucous leukoplakia lesions

OBJECTIVE

This study aimed to survey the presence of known oncoviruses in oral biopsies from patients diagnosed with the aetiologically undetermined proliferative verrucous leukoplakia and compare results to those from milder oral leukoplakia (OL) cases, oral squamous cell carcinoma, a common outcome of the lesions of interest, and healthy controls.

DESIGN

Blind, retrospective, case-control study.

SETTING

A stomatology unit in an academic Hospital and a Public Health laboratory.

PARTICIPANTS

Forty patients were divided in four groups. Ten patients had been diagnosed with proliferative verrucous leukoplakia, 10 with OL and 10 with OSCC, and 10 were healthy subjects.

MAIN OUTCOME MEASURES

The presence or absence of oncovirus DNA was assayed with the amplification of viral genetic markers using PCR and subsequent gel electrophoresis confirmation. Amplified fragments were sequenced and identified bioinformatically.

RESULTS

No DNA from the herpesvirus, papillomavirus or polyomavirus species was detected in the samples.

CONCLUSIONS

No association between proliferative verrucous leukoplakia and target viruses was detected. A higher throughput viral metagenomic approach may prove valuable for future analyses, as it would not be restricted to a priori knowledge of potential targets.

Proliferative verrucous leukoplakia: recognition and differentiation from conventional leukoplakia and mimics

The majority of conventional leukoplakia remains constant and only a subset progress to high-grade dysplasia or invasive carcinoma. A less recognized form known as proliferative verrucous leukoplakia (PVL) represents a unique progressive and elusive variant. Identifying patients with this form can only be achieved through the keen clinical observation of the temporal gross and histologic progression in individual patients with squamous cell carcinoma. The difficulty in the early diagnosis of PVL stems from the overlapping clinical and pathologic features with conventional multifocal leukoplakia with dysplasia. We present the current view on the clinicopathologic and biological characteristics of PVL and discuss their diagnosis, differential diagnosis, and management.

Diagnostic criteria in proliferative verrucous leukoplakia: evaluation

Objectives: to evaluate the ability of the diagnostic criteria proposed by Cerero et al in 2010 to perform an early diagnose in patients with proliferative verrucous leukoplakia. Study Design: retrospective study with patients diagnosed with leukoplakia at Oral Medicine Service at Oral Medicine and Surgery Department at Dentistry Faculty at Universidad Complutense of Madrid. Results: the criteria were applied in 116 patients, turning positive in 40 cases. Out of these, 24 (60%) had been previously diagnosed with PVL. Most frequent criteria were major criteria A and E, concerning lesion’s site and histopathology, and minor criteria b and c, concerning sex and smoking habit. Conclusions: diagnostic criteria developed by Cerero et al can be a useful tool for an early diagnose of PVL, as in 60% of the cases, the criteria would have allowed to make an early diagnose of the disease.

Key words:Proliferative verrucous leukoplakia, criteria, diagnose, early.

Proliferative verrucous leukoplakia: an elusive disorder

Proliferative Verrucous Leukoplakia (PVL) is a multifocal form of progressive leukoplakia with a high rate of malignant transformation that requires early recognition by oral health care providers for proper management.

BACKGROUND AND PURPOSE

PVL will frequently appear as an innocuous white lesion or lesions that can easily be overlooked or considered clinically insignificant, yet it has a high rate of malignant transformation. There is limited in-depth knowledge about the pathobiology of PVL. Oral health care providers lack familiarity with this lesion; consequently the intent of this article is to increase awareness of the clinical aspects of PVL.

METHODS

Case reports, case series and review articles provide a profile of PVL.

CONCLUSION

It is essential that health care providers performing intraoral examinations are aware that PVL is a distinct and rare form of multifocal oral leukoplakia. PVL commonly affects females above the age of 62. Currently, little is known about its etiopathogenesis. Additionally, no specific treatment modality has proven to be effective in aborting its progression. Because of its high recurrence potential and relentless progression to squamous cell carcinoma, all recurrent and multifocal white lesions of the oral cavity should be viewed with suspicion.

Urban legends series: oral leukoplakia

To date, the term oral leukoplakia (OL) should be used to recognize 'predominantly white plaques of questionable risk, having excluded (other) known diseases or disorders that carry no increased risk of cancer'. In this review, we addressed four controversial topics regarding oral leukoplakias (OLs): (i) Do tobacco and alcohol cause OLs?, (ii) What percentage of OLs transform into oral squamous cell carcinoma (OSCC)?, (iii) Can we distinguish between premalignant and innocent OLs?, and (iv) Is proliferative verrucous leukoplakia (PVL) a specific entity or just a form of multifocal leukoplakia? Results of extensive literature search suggest that (i) no definitive evidence for direct causal relationship between smoked tobacco and alcohol as causative factors of OLs, (ii and iii) the vast majority of OLs follow a benign course and do not progress into a cancer, and no widely accepted and/or validated clinical and/or biological factors can predict malignant transformation, and (iv) the distinction between multifocal/multiple leukoplakias and PVL in their early presentation is impossible; the temporal clinical progression and the high rate of recurrences and development of cancer of PVL are the most reliable features for diagnosis.

High incidence of DNA ploidy abnormalities and increased Mcm2 expression may predict malignant change in oral proliferative verrucous leukoplakia

AIMS

To assess the DNA content of cases of oral proliferative verrucous leukoplakia (PVL) and correlate the DNA ploidy findings with the expression of Mcm2, geminin, and Ki67, and with clinicopathological data.

METHODS AND RESULTS

DNA quantification was performed by image cytometry using the ACIS III Automated Cellular Imaging System. Expression of Ki67, Mcm2 and geminin was determined by immunohistochemistry. There were 21 cases of PVL, the female/male ratio was 6:1, and the average age was 65.5 years. Seventeen patients (81.0%) did not report tobacco and alcohol consumption. Nine patients (42.9%) developed verrucous or squamous cell carcinoma. Levels of Mcm2 expression showed a positive correlation with increasingly severe epithelial changes (P = 0.03). Twenty patients had their DNA examined by ACIS III, and 19 (95%) showed aneuploidy. The frequency and severity of aneuploidy (P < 0.0001), the mean values of the DNA heterogeneity index (P < 0.0001) and the 5n-exceeding fractions (P = 0.0007) increased according to epithelial alterations. Abnormal DNA content was observed even in the more indolent lesions.

CONCLUSIONS

Mcm2 expression and DNA ploidy analysis could be used to predict areas of malignant transformation. The clinicopathological findings associated with the immunohistochemical and DNA ploidy results support the distinct and aggressive profile of this entity.

Current evidence in diagnosis and treatment of proliferative verrucous leukoplakia

Proliferative verrucous leukoplakia is multifocal and progressive lesion with a high rate of malignant transformation. This short review highlights the diagnosis, traditional treatment and the current management of the disease. A MEDLINE search for the specific English word including proliferative verrucous leukoplakia in the last two years (2009-2010). This study indicates the current evidence for the diagnosis and the management of proliferative verrucous leukoplakia to help the specialist in this domain for early diagnosis of proliferative verrucous leukoplakia according to the new criteria of diagnosis to prevent the recurrence and any malignant transformation.

Case report of rapidly progressive proliferative verrucous leukoplakia and a proposal for aetiology in mainland China

Proliferative verrucous leukoplakia (PVL) is a rare oral leukoplakia and has four features such as chronic proliferation, multiple occurrences, refractoriness to treatment and high rate of malignant transformation. As mentioned above, most PVL cases processed to malignancy over many years, sometimes 20 years. However, this report described a case of rapid progress, which had malignant transformation in a short period. Additionally, the aetiology of PVL was discussed and immunity was proposed as the possible cause.

Clinicopathological features and immunohistochemical expression of p53, Ki-67, Mcm-2 and Mcm-5 in proliferative verrucous leukoplakia

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.