Diagnostic criteria in proliferative verrucous leukoplakia: evaluation

Characterization of initial/early histologic features of proliferative leukoplakia and correlation with malignant transformation: a multicenter study

The aim of this multicenter retrospective study is to characterize the histopathologic features of initial/early biopsies of proliferative leukoplakia (PL; also known as proliferative verrucous leukoplakia), and to analyze the correlation between histopathologic features and malignant transformation (MT). Patients with a clinical diagnosis of PL who have at least one biopsy and one follow-up visit were included in this study. Initial/early biopsy specimens were reviewed. The biopsies were evaluated for the presence of squamous cell carcinoma (SCCa), oral epithelial dysplasia (OED), and atypical verrucous hyperplasia (AVH). Cases that lacked unequivocal features of dysplasia were termed "hyperkeratosis/parakeratosis not reactive (HkNR)". Pearson chi-square test and Wilcoxon test were used for statistical analysis. There were 86 early/initial biopsies from 59 patients; 74.6% were females. Most of the cases had a smooth/homogenous (34.8%) or fissured appearance (32.6%), and only 13.0% had a verrucous appearance. The most common biopsy site was the gingiva/alveolar mucosa (40.8%) and buccal mucosa (25.0%). The most common histologic diagnosis was OED (53.5%) followed by HkNR (31.4%). Of note, two-thirds of HkNR cases showed only hyperkeratosis and epithelial atrophy. A lymphocytic band was seen in 34.8% of OED cases and 29.6% of HkNR cases, mostly associated with epithelial atrophy. Twenty-eight patients (47.5%) developed carcinoma and 28.9% of early/initial biopsy sites underwent MT. The mortality rate was 11.9%. Our findings show that one-third of cases of PL do not show OED with most exhibiting hyperkeratosis and epithelial atrophy, but MT nevertheless occurred at such sites in 3.7% of cases.

Lichenoid areas may arise in early stages of proliferative verrucous leukoplakia: A long-term study of 34 patients

Background

Proliferative verrucous leukoplakia is considered an uncommon oral potentially malignant disorder with a high malignant transformation rate. The objective of this paper was to define its cancer incidence and related risk factors.

Methods

A retrospective audit of 34 patients diagnosed with proliferative verrucous leukoplakia from a university‐based unit, during the period from 1995 to 2019 was performed. The mean number of visits was 23 ± 18.6. The follow‐up was divided into four‐time intervals to evaluate the clinical presentation, number of lesions, dysplasia grade, and malignant transformation rate.

Results

The majority of patients were females 29 (85.3%), with verrucous component (77.8%), with a gingival presentation (31.8%), and with a preceding lichenoid area (44.1%). Eleven patients (32.4%) were affected by oral cancer during the follow‐up, developing a total of 15 carcinomas. The mean age of malignant transformation was 67.2 ± 12.9 years, particularly 8 ± 8.5 from the onset of the lesions. Warty forms presented a higher mean estimate for malignant transformation (15.2 years, 95% confidence interval 4.4–26 years) than nodular forms (1.9 years, 95% confidence interval 1.9–1.9) (p = 0.019). Patients with an initial proliferative verrucous leukoplakia diagnosis suffered a higher risk of malignancy, particularly 15.55 times (95% confidence interval 1.69–143.17; p = 0.015) than those who did present a preceding area with lichenoid morphology.

Conclusion

Proliferative verrucous leukoplakia presented a high malignant transformation rate and sometimes displayed preceding oral lichenoid areas in early stages. Further studies are needed to understand the impact of these lichenoid areas in proliferative verrucous leukoplakia progression.

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.

A Scoping Review on Gaps in the Diagnostic Criteria for Proliferative Verrucous Leukoplakia: A Conceptual Proposal and Diagnostic Evidence-Based Criteria

Proliferative verrucous leukoplakia (PVL) is considered as an oral potentially malignant disorder (OPMD) that presents with a high tendency to recurrence after treatment and has the highest malignant transformation ratio among all OPMD (50%). Evidence-based publications have indicated that the malignant evolution reported is significantly related to the inconsistent diagnostic criteria used in primary-level studies; so, it has been hypothesized that the risk of oral cancer for this disease could even be underestimated. This is important because PVL requires specific management protocols, evidence-based, aimed at the early diagnosis of cancer developing in these lesions. We present a scoping review-a novel approach to mapping the available literature on a given topic to provide an overview of the available research evidence and to highlight possible gaps in the evidence-especially related in our study to the diagnostic aspects of PVL, and to issue a conceptual proposal and diagnostic criteria for PVL. We conclude that PVL is a white, multifocal and progressive lesion with a high malignant transformation rate which is diagnosed mainly around the age of 60 years without any specific histological characterization. We also advise a personal reflection on the level of certainty with which the clinician makes the diagnosis of a particular case of PVL.

Proliferative Verrucous Leukoplakia Revisited: A Retrospective Clinicopathological Study

(1) Objective: To review the criteria proposed by Cerero-Lapiedra et al. and to retrospectively identify the under-diagnosed disease in patients diagnosed with proliferative verrucous leukoplakia. (2) Materials and methods: In this study, we included patients who were diagnosed with leukoplakia (histological label consistent with the clinical diagnosis, n = 95), and cases with a final diagnosis within the spectrum of proliferative verrucous leukoplakia (n = 110) as defined by Batsakis et al. We applied the criteria proposed by Cerero-Lepiedra et al. to screen for the possible cases of proliferative verrucous leukoplakia. (3) Results: Although many of our patients satisfied specific isolated criteria, only 11 cases satisfied specific combinations of the guidelines to satisfy a diagnosis of proliferative verrucous leukoplakia. However, due to the lack of follow-up data, the disease is not confirmed in these 11 cases. (4) Conclusion: A limited number of cases of proliferative verrucous leukoplakia were diagnosed using the criteria given by Cerero-Lapiedra et al. The true natural history of the disease could not be studied due to the lack of follow-up data. (5) Clinical relevance: Proliferative verrucous leukoplakia presenting as hyperkeratosis or mild epithelial dysplasia are often not followed up, and they subsequently transform into carcinoma. Thus, clinicians must be vigilant whenever they encounter leukoplakia, especially with multifocal presentations. In such cases, the follow-up data are the key to understanding the true nature of the disease entity.

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.

Immune expression profile identification in a group of proliferative verrucous leukoplakia patients: a pre-cancer niche for oral squamous cell carcinoma development

OBJECTIVES

To explore the pathophysiology of proliferative verrucous leukoplakia, a rare oral disorder that exhibits high rates of recurrence and malignant transformation, through a RNAseq case-control study.

MATERIAL AND METHODS

We obtained oral biopsies from 10 patients with verrucous leukoplakia lesions and from the mucosa of 5 healthy individuals for sequencing using RNAseq technology. Using bioinformatic methods, we investigated gene expression and enrichment differences between patients both with and without the disorder. We applied network biology methods to investigate functional relations among those genes that were differentially deregulated.

RESULTS

We detected 140 differentially expressed genes with distinct roles in immune surveillance, tissue and organ morphogenesis, development, and organization. Of these 140 genes, 111 have been previously described as cancer expression biomarkers, being oral squamous cell carcinoma the most represented type of cancer among them. Of these 140 genes, 26 were prioritized for further investigation as biomarkers using larger sample sizes.

CONCLUSIONS

The gene expression patterns of healthy and unhealthy patients differed in 140 genes whose deregulation has a functional impact on normal functioning of the immune system. This immune expression profile provides a plausible hypothesis to explain the transformation to oral squamous cell carcinoma observed in 6 of the 10 assayed cases.

CLINICAL RELEVANCE

By determining the molecular bases of the proliferative verrucous leukoplakia disorder and identifying early biomarkers of malignancy, this can allow us to develop new treatment strategies.

Inter-observer Variability in the Diagnosis of Proliferative Verrucous Leukoplakia: Clinical Implications for Oral and Maxillofacial Surgeon Understanding: A Collaborative Pilot Study

The use of diverse terminology may lead to inconsistent diagnosis and subsequent mistreatment of lesions within the proliferative verrucous leukoplakia (PVL) spectrum. The objectives of this study were: (a) to measure inter-observer variability between a variety of pathologists diagnosing PVL lesions; and (b) to evaluate the impact of diverse terminologies on understanding, interpretation, and subsequent treatment planning by oral and maxillofacial surgeons (OMFS). Six oral pathologists (OP) and six head and neck pathologists (HNP) reviewed 40 digitally scanned slides of PVL-type lesions. Inter-observer agreement on diagnoses was evaluated by Fleiss' kappa analysis. The most commonly used diagnostic terminologies were sent to ten OMFS to evaluate their resulting interpretations and potential follow-up treatment approaches. The overall means of the surgeons' responses were compared by Student t test. There was poor inter-observer agreement between pathologists on the diagnosis of PVL lesions (κ = 0.270), although there was good agreement (κ = 0.650) when diagnosing frankly malignant lesions. The lowest agreement was in diagnosing verrucous hyperplasia (VH) with/without dysplasia, atypical epithelial proliferation (AEP), and verrucous carcinoma (VC). The OMFS showed the lowest agreement on identical categories of non-malignant diagnoses, specifically VH and AEP. This study demonstrates a lack of standardized terminology and diagnostic criteria for the spectrum of PVL lesions. We recommend adopting standardized criteria and terminology, proposed and established by an expert panel white paper, to assist pathologists and clinicians in uniformly diagnosing and managing PVL spectrum lesions.

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.

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.

The development of proliferative verrucous leukoplakia in oral lichen planus. A preliminary study

Background

Was to describe 14 cases of a proliferative verrucous leukoplakia as a clinical evolution of oral lichen planus.

Material and Methods

The clinical and histopathological characteristics of 14 cases of OLP that progress towards a plaque-like and verrucous form were indicated, with monitoring over a period of six to 24.3 years.

Results

The female/male ratio was 11/3, (78.6 and 21.4%). The mean age when the first biopsy was undertaken was 56.4 years old. None of the patients smoked during the study. As bilateral reticular was clinically diagnostic criterion, the second most frequent clinical form was the plaque form (n=10; 71.4%), followed by the atrophic (n=6; 42.8%), and erosive forms (n=4; 28.5%). Clinically it spread towards attached gingival mucosa and the hard palate. In the histopathologic study, there were a predominance of hyperkeratosis and verrucous epithelial hyperplasia. Three of the cases progressed to a squamous cell carcinoma, and one patient developed two verrucous carcinoma.

Conclusions

Further research is needed to demonstrate if proliferative multifocal oral lichen planus and proliferative multifocal oral leukoplakia are the same disorder but have different behaviour of malignancy for reasons of origin.

Key words:Oral lichen planus, proliferative verrucous oral leukoplakia, malignant oral lichen planus, multifocal verrucous oral lichen planus, proliferative verrucous oral lichen planus.

[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.