Malignant transformation of oral lichen planus

An Evidence-Based Update on the Potential for Malignancy of Oral Lichen Planus and Related Conditions: A Systematic Review and Meta-Analysis

A systematic review and a meta-analysis is presented on published articles on the malignant transformation of oral lichen planus (OLP) and related conditions, which, based on current evidence, updates an earlier systematic review published by our research group that included publications until November 2018. In this updated study (Nov-2023) we searched MEDLINE, Embase, Web of Science, and Scopus. We evaluated the methodological quality of studies (QUIPS tool) and carried out meta-analyses. The inclusion criteria were met by 101 studies (38,083 patients), of which, 20 new primary-level studies (11,512 patients) were published in the last 5 years and were added to our updated study. The pooled malignant transformation ratio was 1.43% (95% CI = 1.09-1.80) for OLP; 1.38% (95% CI = 0.16-3.38) for oral lichenoid lesions; 1.20% (95% CI = 0.00-4.25) for lichenoid reactions; and 5.13% (95% CI = 1.90-9.43) for OLP with dysplasia. No significant differences were found between the OLL or LR groups and the OLP subgroup (p = 0.853 and p = 0.328, respectively), and the malignant transformation was significantly higher for the OLP with dysplasia group in comparison with the OLP group (p = 0.001). The factors that had a significant impact with a higher risk of malignant transformation were the presence of epithelial dysplasia, a higher methodological quality, the consumption of tobacco and alcohol, the location of lesions on the tongue, the presence of atrophic and erosive lesions, and infection by the hepatitis C virus. In conclusion, OLP behaves as an oral potentially malignant disorder (OPMD), whose malignancy ratio is probably underestimated as a consequence essentially of the use of inadequate diagnostic criteria and the low methodological quality of the studies on the subject.

Review of Nail Lichen Planus: Epidemiology, Pathogenesis, Diagnosis, and Treatment

Nail lichen planus is an inflammatory disorder of the nails with potential for significant cosmetic disfigurement and functional impairment. Nail manifestations may be isolated or appear concurrently with other forms of lichen planus. Longitudinal ridging is the most common clinical finding, but progressive disease may result in irreversible scarring (dorsal pterygium) or permanent nail loss (anonychia). Data on treatment are limited to retrospective studies and case reports. The mainstays of treatment are intralesional and intramuscular corticosteroid injections and oral retinoids. There is a need for randomized controlled trials on nail lichen planus to more rigorously assess efficacy and outcomes.

Malignant transformation in oral lichen planus and lichenoid lesions: a 14-year longitudinal retrospective cohort study of 829 patients in New Zealand

OBJECTIVE

The aim of this study was to identify the rate of malignant transformation in a longitudinal cohort of patients with oral lichen planus and oral lichenoid lesion (OLP/OLL) and to assess the associations between clinicopathologic aspects and malignant transformation.

STUDY DESIGN

Data were taken from the records of 829 patients histologically diagnosed with OLP/OLL in the years 2005 to 2018.

RESULTS

Of the study patients, 548 (66.1%) were females and 281 (33.9%) were males. The average age at diagnosis was 57.3 years. The hyperplastic type was the most frequent (58.5%). Most patients had multiple sites of involvement, with the buccal mucosa being the most frequent site of biopsy. Oral epithelial dysplasia developed in 5 (0.6%) patients with a previous histologic diagnosis of OLP/OLL and developed oral squamous cell carcinoma (OSCC) in 23 patients (2.8%) during the follow-up period. The atrophic/ulcerative forms are 25.8 times more likely to progress to OSCC compared with the hyperplastic types (hazard ratio [HR] 25.8; P < .05). The HR increases by 5% with every year of age (HR 1.05; 95% confidence interval; P < .05).

CONCLUSIONS

In our study, oral epithelial dysplasia developed in less than 1% of patients with OLP/OLL, and OSCC in 2.8%during the follow-up period. The atrophic/ulcerative forms are 25.8 times more likely to progress to OSCC compared with the hyperplastic types. The HR increases by 5% with every year of age.

Clinicopathological and prognostic characteristics of oral squamous cell carcinomas arising in patients with oral lichen planus: A systematic review and a comprehensive meta-analysis

OBJECTIVES

To evaluate current evidence in relation to the prognostic and clinicopathological significance of oral squamous cell carcinomas arising in patients with oral lichen planus (OLP-OSCC).

MATERIAL AND METHODS

We searched PubMed, Embase, Web of Science and Scopus for studies published before May-2019. We evaluated the quality of studies (QUIPS tool). We carried out meta-analyses to fulfill our objective. We examined the between-study heterogeneity and small-study effects, and conducted sensitivity and subgroup analyses.

RESULTS

Inclusion criteria were met by 27 studies (10,505 patients with OLP, of whom 205 developed a total of 247 OSCCs). The combined 5-year mortality rate was 15.48% for OLP-OSCC (95%CI  =  7.34-25.19), clearly lower than the 34.70-50.00% mortality rate for conventional oral cancer communicated in previous official reports. Also, 14.67% (95%CI  =  6.34-24.81) of OLP-OSCC developed N+ status, compared to 47.00% of conventional oral carcinomas. Likewise, most of the OSCCs in the study were T1/T2 (93.57%, 95%CI  =  82.20-99.88) and presented at stage I/II (81.51%, 95%CI = 68.32-92.38) at the time of diagnosis, which contrasts with 50.00% of conventional carcinomas diagnosed in stages I/II. Furthermore, most of the cases were grade I (well differentiated OSCC) (67.79%; 95%CI = 43.50-88.65), in comparison to conventional OSCCs, which present typically in grade II in 90.00% of cases. Our results also show an 11.21% of the OLP-OSCC patients in this study developed multiple tumors.

CONCLUSIONS

Oral squamous cell carcinomas that developed in oral lichen planus show favorable prognostic parameters, especially with regard to the mortality rate. Around 11% of OLP-OSCC patients develop multiple tumors, which confirms that OLP can lead to field cancerization.

Oral Lichen Planus-Associated Oral Cavity Squamous Cell Carcinoma Is Associated With Improved Survival and Increased Risk of Recurrence

PURPOSE

We investigated the overall survival (OS), disease-specific survival (DSS), and disease-free survival among patients with oral lichen planus-associated oral cavity squamous cell carcinoma (OLP-OCSCC). The secondary objective was to assess the annual risk of tumor recurrence or second primary tumor (SPT).

MATERIALS AND METHODS

A comparative retrospective study was performed of patients with OLP-OCSCC presenting between June 2007 and December 2018 to the Department of Oral and Maxillofacial Surgery, Michigan Medicine (Ann Arbor, MI) and patients with OCSCC in the National Cancer Institute Surveillance, Epidemiology, and End Results (SEER) database (1973 to 2015).

RESULTS

A total of 87 patients with OLP-OCSCC met the inclusion criteria, and 55,165 patients with OCSCC from the SEER database were included. The proportion of women was greater in the OLP group than in the SEER group (56.3 vs 38.0%; P < .001). In the OLP group, 47.1% had no smoking history and 43.7% had no alcohol history. Most patients in the OLP group had presented with stage I disease (46.0%) compared with 31.7% in the SEER group (P = .004). Overall, the OS and DSS were significantly greater in the OLP group than in the SEER group at all points from 1 to 5 years (P ≤ .01). In the OLP group, 46 patients (52.9%) had at least 1 recurrence or SPT. At 10 years, the predicted mean number of recurrences was 1.93 per patient (95% confidence interval, 1.56 to 2.39).

CONCLUSIONS

OLP-OCSCC frequently affects women, nonsmokers, and nondrinkers and presents with localized disease at a high frequency. Patients with OLP-OCSCC have increased OS and DSS and a greater risk of tumor recurrence or SPT compared with OCSCC in the general population. Lifelong, frequent surveillance is recommended for patients with OLP-OCSCC owing to the risk of late recurrence. Future studies are needed to understand the pathophysiology of OLP-OCSCC.

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.

Malignant transformation risk of oral lichen planus: A systematic review and comprehensive meta-analysis

OBJECTIVES

To evaluate current evidence on the malignant transformation of oral lichen planus (OLP), oral lichenoid lesions (OLLs), and oral lichenoid reactions (LRs) and to determine the variables with greatest influence on cancer development.

MATERIAL AND METHODS

We searched PubMed, Embase, Web of Science, and Scopus for studies published before November 2018. We evaluated the quality of studies (QUIPS tool). We carried out meta-analyses to fulfill our objectives. We examined the between-study heterogeneity and small-study effects, and conducted sensitivity studies and subgroup analyses.

RESULTS

Inclusion criteria were met by 82 studies (26,742 patients. The combined malignant transformation rate was 1.14% for OLP (95% CI = 0.84-1.49), 1.88% for OLLs (95% CI = 0.15-4.95) and 1.71% for LRs (95% CI = 0.00-5.46). Subgroup analysis revealed a higher malignant transformation rate in studies when the presence of epithelial dysplasia was not an exclusion criterion (p = 0.001), when both clinical and histopathological criteria were used for diagnosis (p < 0.001), when the follow-up was at least 12 months (p = 0.048), and when there was lower risk of potential bias (p = 0.002). Malignant transformation risk factors were: tongue localization (RR = 1.82, 95% CI = 1.21-2.74, p = 0.004), presence of atrophic-erosive lesions (RR = 4.09, 95% CI = 2.40-6.98, p < 0.001), tobacco use (RR = 1.98, 95% CI = 1.28-3.05, p = 0.002), alcohol consumption (RR = 2.28, 95% CI = 1.14-4.56, p = 0.02), and hepatitis C virus infection (RR = 4.46, 95% CI = 0.98-20.22, p = 0.053).

CONCLUSIONS

The malignant transformation rates of OLP, OLLs and LRs are underestimated due essentially to restrictive diagnostic criteria, inadequate follow-up periods, and/or low quality of studies.

Rate of malignant transformation of oral lichen planus: A systematic review

OBJECTIVE

The aim of this study was to systematically review the literature to determine: (a) the malignant transformation rate (TR) of oral lichen planus (OLP) and its risk factors; (b) whether or not oral lichenoid lesions (OLL) have a different malignant TR.

MATERIALS AND METHODS

PubMed, Scopus, and Web of Science were used as search engines: only observational, full-length, English language studies were investigated. PRISMA protocol was used to evaluate and present results. PROSPERO registration code is CRD42016048529.

RESULTS

Among 7,429 records screened, only 21 were included in this review. Ninety-two of 6,559 patients developed oral squamous cell carcinoma, with an overall TR of 1.40% (1.37% for OLP and 2.43% for OLL), an annual TR of 0.20%. Female gender, red clinical forms, and tongue site seem to slightly increase the transformation risk.

CONCLUSIONS

This systematic review confirms that both OLP and OLL, the latter with a slightly higher TR, may be considered potentially malignant disorders and suggest that erosive type, female gender and tongue site should be considered as risk factors for OLP transformation. Major efforts should be done to establish strict clinical and histological criteria to diagnose OLP and to perform sounder methodological observational studies.

Squamous Cell Carcinomas in Two Cases of Nail Lichen Planus: Is There a Real Association?

Lichen planus (LP) is a chronic inflammatory disease that affects the skin and oral mucosa. Although its etiology is unknown, its potential for cancerization has been confirmed. We herein report the cases of a brother and sister, both with a 15-year history of nail lichen planus of the fingers and toes, who developed squamous cell carcinomas of the nail bed and matrix. This article shows the potential for malignant transformation in lichen planus disease and highlights the importance of periodic clinical follow-up.

Crosstalk between DNA Damage and Inflammation in the Multiple Steps of Carcinogenesis

Inflammation can be induced by chronic infection, inflammatory diseases and physicochemical factors. Chronic inflammation is estimated to contribute to approximately 25% of human cancers. Under inflammatory conditions, inflammatory and epithelial cells release reactive oxygen (ROS) and nitrogen species (RNS), which are capable of causing DNA damage, including the formation of 8-oxo-7,8-dihydro-2'-deoxyguanosine and 8-nitroguanine. We reported that 8-nitroguanine was clearly formed at the sites of cancer induced by infectious agents including Helicobacter pylori, inflammatory diseases including Barrett's esophagus, and physicochemical factors including asbestos. DNA damage can lead to mutations and genomic instability if not properly repaired. Moreover, DNA damage response can also induce high mobility group box 1-generating inflammatory microenvironment, which is characterized by hypoxia. Hypoxia induces hypoxia-inducible factor and inducible nitric oxide synthase (iNOS), which increases the levels of intracellular RNS and ROS, resulting DNA damage in progression with poor prognosis. Furthermore, tumor-producing inflammation can induce nuclear factor-κB, resulting in iNOS-dependent DNA damage. Therefore, crosstalk between DNA damage and inflammation may play important roles in cancer development. A proposed mechanism for the crosstalk may explain why aspirin decreases the long-term risk of cancer mortality.

Clinicopathological Profile and Malignant Transformation in Oral Lichen Planus: A Retrospective Study

OBJECTIVES

The aim of this study was to analyze the histopathologically diagnosed cases of oral lichen planus (OLP) in terms of age, gender, clinical variant, site, hyperpigmentation, systemic illness, grade of dysplasia, and associated malignant transformation. This study also intended to do a review of reported cases of OLP with malignant transformation.

MATERIALS AND METHODS

One hundred and forty-three cases of histopathologically diagnosed OLP between 2010 and 2016 were retrospectively reviewed. Demographic and clinicopathological data including malignant transformation were obtained. The data obtained were analyzed using the Statistical Package for the Social Sciences (SPSS) software for Windows version 20.0 (IBM SPSS, SPSS Inc., Chicago, IL, USA). A review of published literature on OLP with malignant transformation was also done from 1988 to 2017 and tabulated.

RESULTS

OLP in this study showed a male predilection with most of the patients in the third decade. The buccal mucosa (bilateral presentation) was the most common site (79.72%), and reticular type was the most common clinical type (79.02%) followed by erosive type (20.98%). The majority (92.31%) of cases were diagnosed with OLP without dysplasia. The rest (7.69%) of dysplastic cases were predominantly seen in the buccal mucosa of 58 years and above, female patients manifesting mainly as erosive type. Two patients (1.4%) previously diagnosed clinically and histopathologically as OLP developed oral squamous cell carcinoma.

CONCLUSION

The present investigation revealed the predominance of OLP among middle-aged male population and the prevalence of bilateral involvement of buccal mucosa. Two of our cases showed malignant transformation over an average period of 3.5 years. The outcome of this study emphasizes the role of clinical follow-up of patients with OLP.

Malignant transformation of oral lichen planus and oral lichenoid lesions: A meta-analysis of 20095 patient data

OBJECTIVES

For over a century, a heated debate existed over the possibility of malignant transformation of oral lichen planus (OLP). We performed this meta-analysis to evaluate the malignant potential of OLP and oral lichenoid lesions (OLL) and investigate the possible risk factors for OLP malignant transformation into oral squamous cell carcinoma (OSCC).

MATERIALS AND METHODS

We searched Medline, Scopus, and Web of Knowledge for relevant observational studies. Data on OLP malignant transformation were calculated as a pooled proportion (PP), using the Der-Simonian Liard method. We performed subgroup analyses by OLP diagnostic criteria, site, and clinical type, using Open Meta[Analyst] software. Data on possible risk factors for malignant transformation were pooled as odds ratios (ORs), using Comprehensive Meta-Analysis software.

RESULTS

Pooling data for OLP malignant transformation from 57 studies (19,676 patients) resulted in an overall PP of 1.1% [95% CI: 0.9%, 1.4%], while pooling data from 14 recent studies that used the World Health Organization-2003 diagnostic criteria resulted in an overall-PP of 0.9% [95% CI: 0.5%, 1.3%]. The risk of malignant transformation was higher (PP=2.5%, 95% CI [1%, 4%]) in OLL patients (419 patients). A significant increase of malignant transformation risk was noted among smokers (OR=2, 95% CI [1.25, 3.22]), alcoholics (OR=3.52, 95% CI [1.54, 8.03]), and HCV-infected patients (OR=5, 95% CI [1.56, 16.07]), compared to patients without these risk factors.

CONCLUSION

A small subset of OLP patients (1.1%) develop OSCC; therefore, regular follow-up for these patients is recommended. A higher incidence of malignant transformation was found among smokers, alcoholics, and HCV-infected patients; however, these associations should be further investigated.

Identification of AgNORs and cytopathological changes in oral lichen planus lesions

OBJECTIVE

To evaluate cytopathological changes in epithelial cells of the oral mucosa of patients with oral lichen planus (OLP) compared with patients without OLP.

SUBJECTS AND METHODS

Swabs were collected from the oral mucosa of 20 patients with OLP (case group) and 20 patients without OLP (control group) using liquid-based cytology. After Papanicolaou staining, the smears were characterized based on Papanicolaou classification and degree of maturation. Nuclear area (NA) measurements, cytoplasmic area (CA) measurements, and the NA/CA ratio were determined from 50 epithelial cells per slide. For quantification of argyrophilic nucleolar organizer regions (AgNORs), the smears were stained with silver nitrate, and the number of AgNORs was counted in 100 cells.

RESULTS

In both groups, there was a predominance of Papanicolaou Class I nucleated cells in the superficial layer. The average values of NA (p>0.05) and CA (p=0.000) were greater in the case group (NA=521.6, CA=22,750.3) compared with the control group (NA=518.9, CA=18,348.0). The NA/CA ratio was 0.025 for the case group and 0.031 for the control group (p=0.004). There was no significant difference between the mean AgNORs values of both groups (p>0.05).

CONCLUSION

The oral mucosa of patients with OLP exhibited significant cytomorphometric changes. However, there was no evidence of malignancy.

Buccal Micronuclei Assay as a Tool For Biomonitoring DNA Damage in Oral Lichen Planus

INTRODUCTION

The malignant transformation rate of Oral Lichen Planus (OLP) is between 0% and 5.8%. Oral lesions of lichen planus clinically presents itself multifocally, simulating the process of field cancerization in high risk malignancies. The Buccal MicroNucleus Cytome Assay (BMN Assay) provides a platform to identify the high risk individuals by evaluating the markers of nuclear damage at an earliest micro invasive phase.

AIM

To evaluate DNA damage in exfoliated buccal mucosal cells in individuals with oral lichen planus lesions and thereby to delineate the high risk group.

MATERIALS AND METHODS

Buccal smears from 22 OLP and 10 control samples were stained in modified Feulgen-Rossenback reaction for micronuclei assay. Cytological evaluation of number of MicroNucleated cells (CMN), Total Number of Micronuclei (TMN) in micronucleated cells was done in both groups.

RESULTS

Frequency of micronucleated cells (CMN) when compared among the study and control group, a mean value of 4.27 ± 1.80 and 0.90 ± 0.88 were obtained respectively. On comparing the total number of micronuclei in the micronucleated cells (TMN) between the study and control groups, a mean value of 5.38 ± 2.42 and 1.5 ± 0.88 were obtained respectively.

CONCLUSION

There was a significant increase in the frequency of micronuclei and the micronucleated cells in the oral lichen planus as compared to normal individuals.

Evaluation of Potential Risk Factors that contribute to Malignant Transformation of Oral Lichen Planus: A Literature Review

AIM

Many studies have suggested that a lesion originally diagnosed as oral lichen planus (OLP) has different possibilities of undergoing malignant transformation in time, although these findings remain a controversial issue; for example, some studies reported different values of potential malignancy of OLP.

INTRODUCTION

World Health Organization (WHO) classifies OLP as a "potentially malignant disorder" with unspecified malignant transformation risk, and suggests that OLP patients should be closely monitored. Numerous studies have attempted to confirm the malignant transformation potential of OLP.

REVIEW RESULTS

The Cochrane Controlled Trials Register, Medline and EMBASE databases, PubMed, Google Scholar, Ovid, Up To Date, BMJ Clinical Evidence, MD Consult, and Science Direct were searched for papers published between 1997 and 2015. The medical subject heading search terms were "lichen planus," "oral lichen planus," "erosive oral lichen planus," "dysplasia," "oral precancerous condition," "oral premalignant condition," oral cancer, oral squamous cell carcinoma (OSCC), and atrophic lichen planus. A total of 120 English language abstracts were reviewed, and 50 relevant articles identified. Because of the extensive literature on the association between OLP and SCC, we have divided the data into genetic and non-genetic factors for more accurate assessment.

CONCLUSION

In this evidence base, malignant transformation ranges from 0 to 37% with a mean of 4.59%. The highest rate of malignancy was noted in erythematosus and erosive lesions. In this way, follow-up of OLP patients could be carried out more efficiently and appropriately.

CLINICAL SIGNIFICANCE

Oral lichen planus is a premalignant lesion. All types of OLP in any site of oral mucosa must be monitored regularly.

Epigenetic Modifications and Accumulation of DNA Double-Strand Breaks in Oral Lichen Planus Lesions Presenting Poor Response to Therapy

Epigenetics refers to changes in cell characteristics that occur independently of modifications to the deoxyribonucleic acid (DNA) sequence. Alterations mediated by epigenetic mechanisms are important factors in cancer progression. Although an exciting prospect, the identification of early epigenetic markers associated with clinical outcome in premalignant and malignant disorders remains elusive. We examined alterations in chromatin acetylation in oral lichen planus (OLP) with distinct clinical behavior and compared the alterations to the levels of DNA double-strand breaks (DSBs). We analyzed 42 OLP patients, who had different responses to therapy, for acetyl-histone H3 at lys9 (H3K9ac), which is associated with enhanced transcription and nuclear decondensation, and the presence of DSBs, as determined by accumulation of phosphorylated γH2AX foci. Patients with high levels of H3K9ac acetylation failed to respond to therapy or experienced disease recurrence shortly after therapy. Similar to H3K9ac, patients who responded poorly to therapy had increased accumulation of DNA DSB, indicating genomic instability. These findings suggest that histone modifications occur in OLP, and H3K9ac and γH2AX histones may serve as epigenetic markers for OLP recurrence.

Oral lichen planus: study of 21 cases

BACKGROUND:

Lichen planus is considered to be the most common dermatological disease involving the oral mucosa.

OBJECTIVE:

To investigate the profile, clinical features, and the presence of dysplasia and candidiasis in patients with oral lichen planus.

METHODS:

A total of 21 patients were selected from 258 patients at risk for oral cancer development.

RESULTS:

Most of the patients were white (76,2%), female (66,6%), with mean age of 58.8 years. Eight were smokers and seven were alcohol consumers. The buccal mucosa was the most affected site, followed by the tongue and the gingiva. The reticular pattern was the most common appearance. Histopathology depicted dysplasia in nine cases and cytopathology was positive for Candida in eight cases in the first appointment.

CONCLUSION:

Our data are similar to the literature. Cytopathology was important for the diagnosis of candidiasis. Although the presence of dysplasia was verified, further studies are necessary to clarify the importance of this finding.

The impact of GSTM1/GSTT1 polymorphism for the risk of oral cancer

OBJECTIVES

Since development of oral squamous cell cancer (OSCC) is triggered by various noxa, different variants of the antioxidant glutathione S-transferases (GSTs) can counteract toxic compounds (e.g., tobacco smoke). Because different polymorphisms of GST are known to have an increased sensitivity to carcinogenic agents, the aim of this study was to analyze whether GSTM1 or GSTT1 polymorphisms increase the risk for the development of OSCC.

MATERIALS AND METHODS

GSTM1 and GSTT1 polymorphism was examined in healthy volunteers (n = 93) and in patients with OSCC (n = 100) by PCR after brush biopsy of oral mucosa. Odds ratio (OR) was calculated to evaluate the risk of oral cancer development.

RESULTS

GSTM1 and GSTT1 deletion was found in 57% (53/93) and 18% (17/93), respectively, in healthy patients, while the OSCC group showed 57% (57/100) for GSTM1 deletion and 22% (22/100) with a deletion of GSTT1. Odds ratio for GSTM1 polymorphism was 1.00 and for GSTT1 1.26. Comparing smokers and nonsmokers with GSTM1 deletion polymorphism, OR was 4.35, while smokers without GSTM1 deletion showed an OR of 1.45. Adapting these data to the smoking habits of the general population in Germany, the OR was 9.25 for smokers with a GSTM1 deletion and OR 6.68 for smokers without a GSTM1 deletion. In smokers with GSTT1 deletion polymorphism, OR was 1.6 (adapted to the smoking habits of the general population: OR 6.16) and 3.16 (OR 8.56) in smokers without deletion in GSTT1 gene.

CONCLUSIONS

Analysis of GST-M1 polymorphism in smokers could help to identify patients with a higher risk for the development of oral cancer.

CLINICAL RELEVANCE

Early detection of OSCC due to a close meshed monitoring program for patients with GST-M1 polymorphism could help to improve the patient outcome. For polymorphism investigations, the oral brush biopsy is a sufficient method to gain DNA material.

[Potentially malignant character of oral lichen planus and lichenoid lesions]

INTRODUCTION

Many authors have reported the possible malignant transformation of oral lichen. The incidence of this event remains controversial. Many authors make a distinction between the "true" oral lichen planus (OLP) and lichenoid lesions (LL) according to the WHO clinical and histological classification. For these authors an increased risk of development of oral cancer could occur only on LL. Our aim was to check this hypothesis on a cohort followed for 10 years.

MATERIAL AND METHODS

We included patients who were referred to our team for the first time between 1995 and 1997, still followed in 2010, with a histological diagnosis of buccal lichen planus. We classified lesions as OLP or LL according to the WHO clinical and histological classification: the two clinical criteria for OLP were a reticulated aspect and bilateral and symmetric lesions. Three histological criteria were necessary for the diagnosis: dense inflammatory infiltrate in the upper lamina propria, liquefaction degeneration of basal keratinocytes, and no signs of dysplasia. The final diagnosis was OLP, when all clinical ad histological criteria were met otherwise it was LL. We studied the patient's outcome between their first consultations and May 2010.

RESULTS

Thirty-two patients, whose data was available, met inclusion criteria. Eight were diagnosed with OLP and 24 with LL. The mean follow-up was 164 months [154-183]. No oral cancer was observed in the OLP group. Two patients in the LL group presented with oral cancer after 45 and 143 months of follow-up.

DISCUSSION

Malignant transformations were observed only in the LL group. Our results correlate with those of Van Der Meij et al. published in 2006. The strict use of the WHO diagnostic criteria seems to allow identifying patients at risk of developing oral cancer (LL) and others with only a benign course of this chronic oral mucosal disease. These results need to be confirmed by prospective multicentric studies.

Treatment of symptomatic oral lichen planus (OLP) with 0.1% tacrolimus powder in Oraguard-B - A pilot prospective study

OBJECTIVES

The purpose of this study was to investigate the efficacy and safety of 0.1% tacrolimus powder in Oraguard-B for the treatment of patients with symptomatic oral lichen planus (OLP).

METHODS

This was a nonrandomized, nonblinded study conducted in the outpatient department. The 20 patients with symptomatic OLP oral lichen planus who were asked to participate in the study were provided with 20-g containers of the study medication. Patients were asked to use the medication over the symptomatic areas three times a day until resolution of the lesion. Patients were recalled to assess the drug response every 15 days.

RESULTS

The duration of treatment ranged from 30 to 183 days, with a mean of 81.8 ± 44.4 days; all 20 patients reported a favourable response to the topical tacrolimus therapy. Eleven patients had complete resolution of their lesions. In 16 of 20 patients, there was marked resolution in symptoms as recorded by visual analogue scale. Out of 10 patients followed up for a period of 3 months, 5 had recurrence of their lesions but with less intensity, and the patients were symptomless. No serious side effects were associated with the study medication.

CONCLUSION

Topical tacrolimus 0.1% in Oraguard-B was effective and safe in treating patients with OLP. However, there is still a need to undertake more detailed and objective clinical studies to determine the exact benefit of tacrolimus compared with conventional therapies and examine the influence of different dose regimes and formulations and assess the incidence of recurrence.

Oral lichen planus (OLP): clinical and complementary diagnosis

Lichen planus is a common disorder of the stratified squamous epithelium that affects oral and genital mucous membranes, skin, nails, and scalp. Oral Lichen Planus (OLP) affects middle-aged women and shows distribution patterns and characteristics such as white striations, white plaques or papules, erythema, blisters and erosions, and may be associated with medication and/or dental materials used by the patient. The clinical diagnosis can only be made if the disease presents classical patterns such as concomitant lesions in the oral mucosa and skin. The laboratory diagnosis is histopathologically characterized by the presence of projections of the epithelium in the form of sawtooth and Civatte bodies and allows the exclusion of dysplasia and malignancy. Direct immunofluorescence is used when there is suspicion of other diseases, such as pemphigus and pemphigoid. OLP is treated with anti-inflammatory agents, particularly topical corticosteroids; new agents and techniques have proved effective. The malignant transformation of OLP and its exact incidence remain controversial. This work aims at presenting, through literature review, the etiopathogenesis, clinical diagnosis, laboratory tests, and complications of OLP.

Up-regulation of EGF receptor and its ligands, AREG, EREG, and HB-EGF in oral lichen planus

OBJECTIVE

This study aimed to investigate the roles of the epidermal growth factor receptor (EGFR) family members and their ligands in oral lichen planus (OLP).

STUDY DESIGN

The expressions of 4 EGFR-like receptors and 6 EGF-like ligands were measured in OLP tissues from 10 patients and compared with the levels in normal oral mucosa (NOM) from 10 healthy donors.

RESULTS

Of the receptors, only EGFR mRNA and protein were more highly expressed in OLP compared with NOM tissues. Regarding the ligands, the mRNAs of amphiregulin (AREG), epiregulin (EREG), and heparin-binding EGF-like growth factor (HB-EGF) were more highly expressed in OLP compared with NOM tissues. These ligands were strongly expressed by infiltrating lamina propria lymphocytes as well as epithelial keratinocytes in OLP lesions, as shown by immunohistochemistry.

CONCLUSIONS

The enhanced EGFR expression on the keratinocytes in OLP lesions and the up-regulation of EGF-like ligands in keratinocytes and infiltrating mononuclear cells could contribute to the carcinogenesis and pathogenesis of OLP.

Pathophysiology, etiologic factors, and clinical management of oral lichen planus, part I: facts and controversies

Lichen planus (LP) is an inflammatory disease of the stratified squamous epithelia of unknown etiology. LP affects most frequently the oral mucosa, but it may also involve other mucosa and the skin. Oral LP (OLP) most frequently affects woman aged between 30 and 60 years. Histopathologic examination typically shows orthokeratotic hyperkeratosis, basal cell degeneration, and a dense well-defined infiltrate of lymphocytes in the superficial dermis. OLP lesions may result from the induction of keratinocytes apoptosis by cytotoxic CD8+ T cells stimulated by a yet unidentified self-antigen on a genetically predisposed patient. The association of OLP with hepatitis C virus (HCV) has been more consistently demonstrated in the Mediterranean area. Although HCV RNA and HCV-specific CD4+ and CD8+ T cells have been retrieved in the mucosal lesions of patients with chronic HCV infection and OLP, the eventual pathophysiology of HCV in OLP lesions remains unclear. Available treatments of OLP are not curative, and many have potentially prominent side effects. The objectives of OLP management should be to prevent and screen for malignant transformation and alleviate symptoms on the long-term. Avoidance of potential precipitating drugs, tobacco, alcohol, and local trauma, as well as strict oral hygiene, is essential. The first-line pharmacologic treatment relies on topical steroids. Systemic steroids should be limited to the short-term cure of severe refractory OLP. Life-long clinical follow-up, at least annually, is fundamental.

The efficacy of topical hyaluronic acid in the management of oral lichen planus

BACKGROUND

The aim of this study was to evaluate the efficacy of a topical hyaluronic acid (HA) gel preparation (0.2%) in the management of oral lichen planus (OLP).

METHODS

A total of 124 patients with erosive OLP participated in a randomized, placebo-controlled, double-blind trial to evaluate the efficacy of a topical HA preparation. Outcome measures included soreness relief following immediate application, oral function and size of erosive/ulcerative area. Patients were medicated for 28 days and completed a log diary recording oral function and soreness scores.

RESULTS

Application of topical HA produced a significant reduction (P < 0.05) in soreness scores when compared with placebo for up to 4 h post-application. There was no difference between treatment groups (P > 0.05) with respect to oral function. Patients treated with 0.2% HA showed a significant reduction (P < 0.05) in the size of the erosive/ulcerated area after 28 days of treatment when compared with baseline. There was no significant difference in changes in ulcerative areas between treatment groups.

CONCLUSIONS

Topical HA (0.2%) does appear to be of some benefit in the management of erosive lichen planus providing efficacy for up to 4 h after administration. Very frequent applications should be considered to obtain a more significant clinical benefit. Topical HA gel may be a useful addition to the treatment option for OLP.

Incidence and treatment outcome of oral lichen planus in Southeast Serbia in a 10-year period (1997-2007)

Background/Aim. Lichen planus is a chronic, immunologic, mucocutaneous disease with a wide range of clinical manifestations. The aim of this retrospective study was to evaluate the most common forms of oral lichen planus (OLP) and its symptoms and to describe treatment responses in patients during 10-year period. Methods. The study was conduced on 163 OLP patients who came in the Department of Oral medicine and Periodontology between 1997 and September 2007. Each case was classified into one of four clinical subtypes: reticular, atrophic, erosive-ulcerative, bullous. Results. There was no significant difference in patients age. Women were found to be significantly more likely to have OLP (p < 0.001). Corticosteroids were effective in reducing symptoms, erythema and healing ulcers. Improvement was shown over a long term in 61.35% patients. Over the long term 38.65% patients maintained the same type of OLP or it became a more severe type. Two patients (1.22%) developed oral carcinoma during the follow-up period. Conclusion. The response of patients with erosive OLP to a short course of systemic corticosteroids often was quite remarkable. However, symptoms and signs tended to recur after this treatment. Periodic examinations, patient education, medical treatment, monitoring of side-effects as well as follow-up biopsies are necessary for management of OLP patients.

Oral lichen planus and lichenoid reactions: etiopathogenesis, diagnosis, management and malignant transformation

Lichen planus, a chronic autoimmune, mucocutaneous disease affects the oral mucosa (oral lichen planus or OLP) besides the skin, genital mucosa, scalp and nails. An immune mediated pathogenesis is recognized in lichen planus although the exact etiology is unknown. The disease most commonly affects middle-aged females. Oral lichenoid reactions (OLR) which are considered variants of OLP, may be regarded as a disease by itself or as an exacerbation of an existing OLP, by the presence of medication (lichenoid drug reactions) or dental materials (contact hypersensitivity). OLP usually presents as white striations (Wickham's striae), white papules, white plaque, erythema, erosions or blisters. Diagnosis of OLP is established either by clinical examination only or by clinical examination with histopathologic confirmation. Direct immunofluorescence examination is only used as an adjunct to the above method of diagnosis and to rule out specific autoimmune diseases such as pemphigus and pemphigoid. Histopathologic features of OLP and OLR are similar with suggestions of certain discriminatory features by some authors. Topical corticosteroids are the treatment of choice for OLP although several other medications have been studied including retinoids, tacrolimus, cyclosporine and photodynamic therapy. Certain OLP undergo malignant transformation and the exact incidence and mechanisms are still controversial. In this paper, etiopathogenesis, diagnosis, management and malignant transformation of OLP and OLR have been reviewed.

Oral lichen planus: controversies surrounding malignant transformation

Studies of the malignant potential of oral lichen planus (OLP) have been hampered by inconsistencies in the diagnostic criteria used for OLP, the criteria adopted to identify a true case of malignant transformation in OLP, the risk factors for malignant transformation and the optimum management of patients to ensure the early diagnosis of transformation. Consensus remains elusive, and leading workers in this field have recently published conflicting reports on the malignant potential of OLP and on the important question of the advisability of excluding patients with epithelial dysplasia or a tobacco habit from studies on this issue. The present review outlines these debates and proposes a possible a molecular basis for the malignant transformation in this disease.

The possible premalignant character of oral lichen planus and oral lichenoid lesions: A prospective five-year follow-up study of 192 patients

Recently, we reported the preliminary results of a prospective study on the possible premalignant character of oral lichen planus (OLP) and oral lichenoid lesions (OLL). Based on these data it was concluded that there was some but no convincing support for the hypothesis that patients with OLL have an increased risk of development of oral cancer, but not so in patients with OLP. In the present treatise the results of prolonged follow-up of this cohort of patients have been described. A study group of 192 patients, 67 patients diagnosed with OLP and 125 patients with OLL, according to revised World Health Organization diagnostic criteria, was followed for periods ranging from 7.6 to 96.9 months (mean, 55.9 months). The expected number of patients with oral cancer in the group of patients with OLP and in the group of patients with OLL was estimated by comparing the number of patients, their ages, sex, and the length of follow-up to annual incidence rates of oral cancer for the general population in The Netherlands. The binomial test was used to determine whether the observed number of cases of cancer in the OLP group and the OLL group exceeded the expected numbers. Four out of 192 patients, two men and two women, developed a squamous cell carcinoma of the oral mucosa during follow-up. All malignant transformations occurred in the OLL group. The malignant transformation of the OLL group, based on a mean follow-up of 53.8 months, was calculated at 0.71% per year. A comparison of the expected against actual figures for the development of carcinomas revealed no increase in patients with OLP and a 142-fold increase in patients with OLL, the latter being statistically significant, with a p-value of 0.044. The present data give support to the hypothesis that patients with OLL have an increased risk of development of oral cancer. There seems to be no increased risk in patients with OLP. In view of our results we advise to monitor only the subgroup of OLL patients twice a year for early detection of possible malignant transformation.

Frequency of micronucleated exfoliated cells in oral lichen planus

OBJECTIVE

The purpose of this study was to determine the frequency of micronucleated exfoliated cells (MEC) in atrophic and erosive oral lichen planus (OLP).

MATERIALS AND METHODS

Twenty-two patients with atrophic and/or erosive OLP participated in this study. Lesions were scored ranging from 0 (no lesion) to 5 (large erosion) according to the severity and assessed for MEC. Exfoliated cells were obtained by swabbing the lesions and normal-appearing mucosa adjacent to the lesions. Swabbing was also performed in age-sex-matched normal individuals. Five hundred exfoliated cells were screened for nuclear anomalies including micronuclei, karyorhexis, pycnosis, and chromatid clumping.

RESULTS

The severity score of OLP ranged from 2 to 4 with the average of 2. The frequency of MEC in OLP patients was 3.79% and 0.37% in the lesions and normal-appearing mucosa, respectively. In normal individuals, the frequency of MEC was also 0.37%. Using a paired t-test, it was found that the MEC frequency in the OLP lesions was significantly elevated (p<0.01) as compared to that in normal-appearing mucosa adjacent to lesions and that in normal individuals. There were no statistically significant differences in the MEC frequency of the three severity scores as analyzed by Kruskal-Wallis one way analysis of variance on ranks (p>0.05).

CONCLUSION

This study revealed an increase in micronuclei in OLP lesions. The results indicate genotoxic damage in atrophic and erosive OLP.

Cell cycle regulating mechanisms in oral lichen planus: Molecular bases in epithelium predisposed to malignant transformation

OBJECTIVE

Expression of p53, p21, ki-67, Bcl-2 and caspase-3 proteins in oral lichen planus (OLP) was studied to investigate cell cycle regulation mechanisms in this disease.

MATERIAL AND METHODS

Oral biopsies were obtained from 51 patients with OLP and 26 controls for immunohistochemical analysis (peroxidase antiperoxidase) to quantify expression of the proteins under study (-: 0%, +: <10%, ++: 10-25%, +++: 26-50%, ++++: >50% positive cells).

RESULTS

Basal expression of caspase-3 was negative in 22 cases (46.8%) and positive in <10% of basal cells in 22 cases (46.8%); caspase-3 expression in inflammatory infiltrate was negative in 22 cases (46.8%) and positive in <10% of lymphocytes in 20 cases (42.5%). Basal expression of Bcl-2 was negative in 35 cases (74.5%); Bcl-2 was expressed in inflammatory infiltrate in 34 cases (72.3%) and was positive in <25% of lymphocytes in 14 of these (29.7%). Basal expression of p53 and p21 was positive in 32 (67.9%) and 23 (48.8%) cases, respectively. Basal expression of ki-67 was positive in 45 cases (95.7%), of which 20 (42.5%) showed positivity in >25% of cells; ki-67 was expressed in inflammatory infiltrate in 23 cases (48.9%). Significant associations were found between basal expressions of p53 and ki-67 (p<0.001) and between Bcl-2 expression in infiltrate and basal expression of ki-67 (p<0.001). No association was observed between basal expressions of p53 and caspase-3 (p=0.08). Bcl-2 expression in infiltrate and basal expression of ki-67 were independently associated with presence of OLP.

CONCLUSIONS

Epithelial cells in OLP do not preferentially develop apoptosis but rather cycle arrest or an increased proliferation rate, which may create a suitable substrate for malignant transformation.

Oxidative and nitrative DNA damage in animals and patients with inflammatory diseases in relation to inflammation-related carcinogenesis

Infection and chronic inflammation are proposed to contribute to carcinogenesis through inflammation-related mechanisms. Infection with hepatitis C virus, Helicobacter pylori and the liver fluke, Opisthorchis viverrini (OV), are important risk factors for hepatocellular carcinoma (HCC), gastric cancer and cholangiocarcinoma, respectively. Inflammatory bowel diseases (IBDs) and oral diseases, such as oral lichen planus (OLP) and leukoplakia, are associated with colon carcinogenesis and oral squamous cell carcinoma (OSCC), respectively. We performed a double immunofluorescence labeling study and found that nitrative and oxidative DNA lesion products, 8-nitroguanine and 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG), were formed and inducible nitric oxide synthase (iNOS) was expressed in epithelial cells and inflammatory cells at the site of carcinogenesis in humans and animal models. Antibacterial, antiviral and antiparasitic drugs dramatically diminished the formation of these DNA lesion markers and iNOS expression. These results suggest that oxidative and nitrative DNA damage occurs at the sites of carcinogenesis, regardless of etiology. Therefore, it is considered that excessive amounts of reactive nitrogen species produced via iNOS during chronic inflammation may play a key role in carcinogenesis by causing DNA damage. On the basis of our results, we propose that 8-nitroguanine is a promising biomarker to evaluate the potential risk of inflammation-mediated carcinogenesis.