Risk of oral squamous cell carcinoma in 402 patients with oral lichen planus: a follow-up study in an Italian population

Scoring systems for Oral Lichen Planus used by differently experienced raters

Background

Scoring systems have been widely used to evaluate the severity and activity of oral lichen planus (OLP). The aim of the present study was to compare two existing (one modified) scoring systems in the evaluation of OLP severity and correlation with pain. Three differently experienced raters were involved.

Material and Methods

Consecutive patients with OLP were assessed for pain using the Visual Analogue Scale and examined at 10 intraoral sites before starting (T0) and three weeks after (T1) steroid therapy (Clobetasol). Three differently experienced raters evaluated photographs using two scoring systems designated White-Erosive-Atrophic (WEA) modified from an older WEA system (WEA-MOD) and Reticular-erythematous-Ulcerative (REU) systems. WEA-MOD Kendall’s W and interclass correlation coefficient were calculated and correlation between REU/WEA-MOD and pain was calculated using Spearman coefficient.

Results

Most patients showed lesions on buccal mucosa (85-93,5%) and maxillary/mandibular gingivae (31,8-31,2%), predominantly reticular. At T0, Kendall-W coefficients of 0.89 and 0.74 were obtained for the REU and WEA respectively. At T1, Kendall-W coefficients of 0.83 and 0.58 were obtained for the REU and WEA respectively. Interclass correlation coefficient ranged from 0.87 to 0.90 for REU and from 0.58 to 0.87 for WEA. REU and WEA scores significantly decreased after therapy (p<0.000) as well as VAS (p<0.05). REU score showed correlation with VAS.

Conclusions

All the raters achieved comparable measures using REU whereas WEA and WEA-MOD seem less reproducible. REU seems to correlate to disease activity and pain.

Key words:Oral lichen planus, scoring system, VAS, REU, WEA, rater.

The role of microRNAs in oral lichenoid disorders. Systematic review

Background

Certain changes in the microRNA expression are considered to be associated with chronic inflammatory processes and with the malignant transformation of oral potentially malignant disorders. The purpose of this systematic review is to update the existing data on the aberrant microRNA expression profiles identified in oral lichenoid disease (OLD).

Material and Methods

A search in PubMed-Medline and Scopus was performed on the English literature published between 2010 and August 2016 using the following keywords: oral lichenoid disease, oral lichen planus and microRNA.

Results

Originally, 25 articles were considered, of which 12 case-control articles were selected according to the inclusion/exclusion criteria.

Conclusions

OLD seems to have altered microRNA expression profile. Certain altered microRNAs (146a, 155) may be useful as biomarkers for this disorder. More studies including larger number of cases are needed in order to study further on the biological processes and on the regulation pathways of these altered microRNAs.

Key words:microRNAs, oral lichenoid disease, oral lichen planus.

Hepatitis C and Risk of Nonhepatic Malignancies

Epidemiologic studies show an increased risk of mortality among hepatitis C virus (HCV)-infected individuals compared with uninfected individuals from hepatic and nonhepatic causes. This article reviews the biologic plausibility of and epidemiologic evidence for the association between HCV and five extrahepatic malignancies: cholangiocarcinoma (CCA), pancreatic adenocarcinoma, papillary thyroid cancer, oral squamous cell cancer, and renal/kidney cancer. There is sufficient evidence to suggest that HCV is associated with intrahepatic CCA. The evidence for the link between HCV and pancreatic adenocarcinoma, oral squamous cell cancer, and renal/kidney cancer is compelling but requires further study. Based on available studies, there is no significant association between HCV, extrahepatic CCA, and papillary thyroid cancer.

High percentage of oral lichen planus and lichenoid lesion in oral squamous cell carcinomas

OBJECTIVE

Oral lichen planus (OLP) and lichenoid lesions (OLL) are regarded as precursor lesions of oral squamous cell carcinoma (OSCC) with potential for malignant transformation. This potential is not clear due to difficulties in diagnosis of OLP and OLL. Our aim was therefore to evaluate previously identified OLP and OLL as precursor lesions in OSCC and to identify cancer related etiological factors such as smoking and alcohol consumption.

MATERIAL AND METHODS

We retrospectively reviewed all cases (total 323, comprising 164 females and 159 males) with OSCC treated at the Department of Oral and Maxillofacial Diseases and Surgery, Helsinki University Hospital during 2015. Confirmed by histopathological biopsy, 58 (17.9%) had OLP and 13 had OLL (4.0%) as precursor lesion.

RESULTS

Patients with OLP were slightly older than those without it. OLP was more common in females than in males (p < .0001). TN class 1 tumors were more prevalent among patients with OLP or OLL (p = .006) and cancer relapses less common (p = .005). Smoking was less frequent in patients with OLP and OLL (p < .0001). Also alcohol abuse was less frequent among these patients (p < .001).

CONCLUSION

Our findings confirm the importance of active follow-up of all patients with OLP and OLL even in patients who do not fit a traditional high-risk category for OSCC.

Can atrophic-erosive oral lichen planus promote cardiovascular diseases? A population-based study

OBJECTIVE

Lichen planus has been recently associated with an increased risk of cardiovascular diseases (CVDs). The oral manifestations can be divided into white hyperkeratotic lesions (WL) and atrophic and erosive lesions (RL). The aim of this report was to compare the presence of CVDs between patients affected by WL or RL, to test the hypothesis that RL are associated with an increased incidence of CVDs.

SUBJECTS AND METHODS

Patients were analysed through a complete collection of all the risk factors for CVDs. The primary endpoint was the occurrence of a cardiovascular event-acute coronary syndrome (ACS), any revascularization or stroke/TIA. A multivariable logistic regression model, adjusted for age at diagnosis, body mass index, smoking, alcohol consumption, diabetes, hypertension, CVDs familiarity and periodontitis, was performed.

RESULTS

A prospective cohort of 307 patients has been evaluated; 185 (60.3%) had WL and 122 RL (39.7%). Twenty-four patients had a CVD. ACS occurred more frequently in RL (adjusted odds ratio 5.83; 95% CI: 1.16-29.39), mainly due to the higher risk of it after the histological diagnosis of Oral lichen planus OLP (odds ratio 4.23; 95% CI: 0.66-27.23).

CONCLUSION

Patients with RL could possibly have a higher risk of developing ACS. Further analysis on larger cohort is however warranted.

Genome-Wide Association Study Identifies Risk Variants for Lichen Planus in Patients With Hepatitis C Virus Infection

BACKGROUND & AIMS

There is a close relationship between hepatitis C virus (HCV) infection and lichen planus, a chronic inflammatory mucocutaneous disease. We performed a genome-wide association study (GWAS) to identify genetic variants associated with HCV-related lichen planus.

METHODS

We conducted a GWAS of 261 patients with HCV infection treated at a tertiary medical center in Japan from October 2007 through January 2013; a total of 71 had lichen planus and 190 had normal oral mucosa. We validated our findings in a GWAS of 38 patients with HCV-associated lichen planus and 7 HCV-infected patients with normal oral mucosa treated at a medical center in Italy.

RESULTS

Single-nucleotide polymorphisms in NRP2 (rs884000) and IGFBP4 (rs538399) were associated with risk of HCV-associated lichen planus (P < 1 × 10^-4). We also found an association between a single-nucleotide polymorphism in the HLA-DR/DQ genes (rs9461799) and susceptibility to HCV-associated lichen planus. The odds ratios for the minor alleles of rs884000, rs538399, and rs9461799 were 3.25 (95% confidence interval, 1.95-5.41), 0.40 (95% confidence interval, 0.25-0.63), and 2.15 (95% confidence interval, 1.41-3.28), respectively.

CONCLUSIONS

In a GWAS of Japanese patients with HCV infection, we replicated associations between previously reported polymorphisms in HLA class II genes and risk for lichen planus. We also identified single-nucleotide polymorphisms in NRP2 and IGFBP4 loci that increase and reduce risk of lichen planus, respectively. These genetic variants might be used to identify patients with HCV infection who are at risk for lichen planus.

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.

Increased melatonin in oral mucosal tissue of oral lichen planus (OLP) patients: A possible link between melatonin and its role in oral mucosal inflammation

OBJECTIVE

The existence of extra-pineal melatonin has been observed in various tissues. No prior studies of melatonin in human oral mucosal tissue under the condition of chronic inflammation have been reported. The aim of this study was to investigate the presence of melatonin in oral mucosal tissue of patients with oral lichen planus (OLP) which was considered as a chronic inflammatory immune-mediated disease causing oral mucosal damage and ulcerations.

MATERIALS AND METHODS

Sections from formalin-fixed and paraffin-embedded oral mucosal tissue of OLP patients (n=30), and control subjects (n=30) were used in this study. Immunohistochemical staining was performed and the semiquantitative scoring system was used to assess the levels of arylalkylamine-N-acetyltransferase (AANAT: a rate-limiting enzyme in the biosynthesis pathway of melatonin), melatonin, and melatonin receptor 1 (MT1) in oral mucosa of OLP patients and normal oral mucosa of control subjects.

RESULTS

AANAT, melatonin, and MT1were detected in oral mucosal tissue of OLP patients and control subjects. Immunostaining scores of AANAT, melatonin, and MT1 in oral mucosal tissue of OLP patients were significantly higher than those in control subjects (p=0.002, p<0.001, and p=0.031, respectively).

CONCLUSIONS

Increased levels of AANAT, melatonin, and MT1 in the inflamed oral mucosal tissue of OLP patients imply that chronic inflammation may induce the local biosynthesis of melatonin via AANAT, and may enhance the action of melatonin via MT1.

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.

Evaluation of cellular proliferative activity in patients with oral lichen planus and hepatitis C through AgNOR method

The objective of this study was to evaluate the cellular proliferative potential of oral lichen planus (OLP) lesions from patients without hepatitis C virus (HCV) by means of AgNOR method, as well as the cellular proliferative potential of the normal oral mucosa from patients with HCV, treated or untreated by interferon and ribavirin. A cross-sectional study was developed to investigate four groups: 10 HCV+ patients without clinical signs of OLP who had never been treated for HCV infection - Group 1; 10 HCV+ patients that were under interferon and ribavirin treatment - Group 2; 15 patients with reticular OLP lesions histopathologically confirmed, without HCV - Group 3; and 15 blood donors without HCV infection and no clinical signs of OLP GROUP 4 Control Group. The cytological material of all groups was collected by the liquid-based cytology technique. Then, the sedimented material from each patient was filled with the Nucleolar Organizer Regions impregnation by silver method (AgNOR). The count of NORs was performed on 100 epithelial cell nuclei per patient using the Image Tool(tm) software. The Tukey HSD test was used to compare the median value of NORs among the groups and showed that the oral mucosa of HCV+ patients previously treated with anti-HCV drugs (GROUP 2), presented a higher average number of NORs in relation to others (p<0.05). The anti-HCV treatment may be related to increased cell proliferation of oral mucosa, indicating a possible relationship between OLP and HCV+ patients treated with interferon and ribavirin.

Refractory Erosive Oral Lichen Planus Associated with Hepatitis C: Response to Topical Tacrolimus Ointment

Background:

Erosive lichen planus is a painful and disabling disease that is frequently resistant to topical and systemic therapies. Current therapies are considered palliative rather than curative as many patients relapse after discontinuing treatment. An association has been reported between some cases of oral lichen planus (OLP) and chronic hepatitis C infection.

Objective:

We report on a 51-year-old hepatitis C-positive man with corticosteroid refractory erosive lichen planus of the lip who had a rapid resolution of his lesions following a two-week course of topical 0.1% tacrolimus ointment. The patient remains symptom-free at one year post-treatment.

Conclusion:

This case supports the safety and efficacy of topical tacrolimus in patients with steroid-refractory OLP associated with chronic hepatitis C.

Genomewide miRNA profiling of oral lichenoid disorders and oral squamous cell carcinoma

OBJECTIVE

To dissect the aberrant microRNA profile of oral lichenoid disorders (OLD) by analyzing the larger set of OLD samples tested so far.

MATERIALS AND METHODS

MicroRNA expression profiles were assessed using TLDA card in 32 samples (16 OLD, 8 OSCC, and 8 control). The findings were validated using RT-qPCR in an independent cohort of 91 samples.

RESULTS

We identified 20 differentially expressed microRNAs in OLD, of which several are functionally related to cell proliferation, response to organic substances, or immune processes. Further validation of the top-ranked microRNAs revealed that they were all aberrantly expressed in OLD.

CONCLUSION

We have identified a new microRNA signature associated with OLD that may provide a meaningful basis for better understanding the physiopathology of the disease. In addition, we validated seven microRNAs whose expression was shown to be higher in OLD tissue in comparison with the control and OSCC tissues.

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.

Phenome-wide association study maps new diseases to the human major histocompatibility complex region

BACKGROUND

Over 160 disease phenotypes have been mapped to the major histocompatibility complex (MHC) region on chromosome 6 by genome-wide association study (GWAS), suggesting that the MHC region as a whole may be involved in the aetiology of many phenotypes, including unstudied diseases. The phenome-wide association study (PheWAS), a powerful and complementary approach to GWAS, has demonstrated its ability to discover and rediscover genetic associations. The objective of this study is to comprehensively investigate the MHC region by PheWAS to identify new phenotypes mapped to this genetically important region.

METHODS

In the current study, we systematically explored the MHC region using PheWAS to associate 2692 MHC-linked variants (minor allele frequency ≥0.01) with 6221 phenotypes in a cohort of 7481 subjects from the Marshfield Clinic Personalized Medicine Research Project.

RESULTS

Findings showed that expected associations previously identified by GWAS could be identified by PheWAS (eg, psoriasis, ankylosing spondylitis, type I diabetes and coeliac disease) with some having strong cross-phenotype associations potentially driven by pleiotropic effects. Importantly, novel associations with eight diseases not previously assessed by GWAS (eg, lichen planus) were also identified and replicated in an independent population. Many of these associated diseases appear to be immune-related disorders. Further assessment of these diseases in 16 484 Marshfield Clinic twins suggests that some of these diseases, including lichen planus, may have genetic aetiologies.

CONCLUSIONS

These results demonstrate that the PheWAS approach is a powerful and novel method to discover SNP-disease associations, and is ideal when characterising cross-phenotype associations, and further emphasise the importance of the MHC region in human health and disease.

[Immunomorphology of oral lichen planus]

The article is devoted to immunohistochemical study of reticular and erosive forms of oral lichen planus. Morphological examination of the reticular form revealed the increased number of Langerhans cells (CD1a), mast cells (CD25) and T lymphocytes (CD4, CD8, CD16) in the oral epithelium. Activation of these cells leads to the secretion of TNF-α and destruction of basal keratinocytes, which manifests as a focal reduction of intercellular protein expression of E-cadherin. Destruction of basal keratinocytes in a reticular form of oral lichen planus is accompanied by a significant decrease in proliferative activity of the basal cell layer (21.7±10.2%) compared with normal mucosa (33.6±7.0%), p=0.0045. In erosive form along with the above changes IgG and C3d complement's elements are revealed, which confirms the activation of immune complex mechanisms in the erosion area.

Behavior of oral squamous cell carcinoma in subjects with prior lichen planus

Objective

To characterize the clinical behavior of oral squamous cell carcinomas (OSCCA) arising in patients with pre-existing oral lichen planus (OLP).

Study Design and Setting

Retrospective case-control study. Disease-free interval, time to first recurrence, subsequent therapy, and overall survival were calculated and compared between cases and controls matched for age, gender, primary site, and tumor stage.

Results

In 10 identified subjects with OLP/OSCCA, mean time from OLP diagnosis to OSCCA was 5.5 years. Three subjects suffered a local recurrence and two developed a second primary OSCCA. Mean actuarial survival for OLP patients was 119 months vs 42 months for the control patients, though this difference was not significant ( P = 0.201, log-rank).

Conclusions

OLP/SCCA subjects may exhibit better actuarial survival than SCCA patients despite a somewhat higher rate of local recurrence and second primary SCCA. Further study is required to characterize the behavior of OSCCA arising in pre-existing OLP.

The Clinical Presentation of Oral Potentially Malignant Disorders

Early detection of oral cancer improves survival rates significantly, however, the incidence of oral cancer has continued to rise in the UK - between 2002-2012, it increased by more than 30%. There is currently no national screening programme for oral cancer, so undertaking a full examination of the oral mucosa during routine dental appointments is vital. Although strong evidence is still lacking, oral cancer is thought to be preceded by oral potential malignant disorders (OPMDs) or oral precancerous diseases. These mainly present as white/red lesions within the mouth and their clinical appearance can be challenging to diagnose accurately, which can lead to them being misdiagnosed as negligible problems. Dentists must keep up to date with OPMDs detection and ensure they are capable of correctly recognising lesions that carry a potential risk. This paper aims to provide a brief overview on OPMDs, highlighting potentially malignant disorders as they may present to the practitioner, showing their typical clinical appearance, and suggesting differential diagnosis and clinical management in dental practice.

Dysplastic change rate in cases of oral lichen planus: A retrospective study of 112 cases in an Iranian population

Backgrounds:

Lichen planus is a chronic systemic disease and oral mucosa is commonly involved. Oral lichen planus (OLP) most commonly affects middle-aged women. The prevalence of the disease ranges between 0.5% and 2.6% in the general population and the range of malignant transformation varies between 0% and 10%.

Objectives:

To assess the rate of malignant transformation of OLP samples.

Materials and Methods:

This retrospective study was carried out on 112 medical records of patients with histological diagnosis of OLP who attended the Department of Pathology at the Educational Hospital from 2005 to 2012. H&E-stained slides were reviewed by two pathologists using strict clinical and histopathological diagnostic World Health Organization (WHO) criteria. Dysplastic changes were diagnosed and graded according to the latest WHO classification.

Results:

Of the 112 cases diagnosed as OLP, there were 39 males and 73 females and the patients’ ages ranged from 15 to 86 years (mean age 44.5 years). The erosive form with fifty cases was the most common clinical type and the papular type with one case was the least common clinical type. Regarding the site, the buccal mucosa was the most common site with 52 cases. Totally, dysplastic changes were found in 12 samples, among them five cases showed mild dysplasia and seven cases showed moderate dysplasia. One case developed oral squamous cell carcinoma after 3 years.

Conclusion:

OLP is considered as a premalignant condition by the WHO and several authors. Although the malignancy rate is not so high, to reduce morbidity and mortality from cancer arising on OLP lesions, a regular follow-up examination is recommended.

A clinical study on oral lichen planus with special emphasis on hyperpigmentation

BACKGROUND

Oral lichen planus (OLP) is a unique disorder affecting generally the older age group. Numerous studies have been done on various aspects of OLP such as pathogenesis, rate of malignant transformation, etc. However, very few studies are available with respect to clinical features especially association of hyperpigmentation and OLP. This study aims at studying the clinical aspects of OLP and study the association between hyperpigmentation and OLP in a south Indian population.

MATERIALS AND METHODS

A total of 58 patients with OLP who attended the outpatient department of our institution were included in the study and a complete history, followed by thorough intraoral examination was done. All the data were recorded and assessed for statistical analysis using SPSS software.

RESULTS

We found that the male to female ratio affected with OLP was 1:1 and the most common form of OLP that was seen was the reticular subtype. Also, buccal mucosa was the most common affected site and more than 60% patients had hyperpigmentation associated with the site affected by OLP. We found a statistically significant relation between the reticular type of OLP and the older age group (51-70 years) with hyperpigmentation.

CONCLUSION

Although further studies are required to say anything conclusively, post-inflammatory changes occurring the mucosa due to OLP could be a cause for hyperpigmentation in the sites affected.

Diagnostic profiling of salivary exosomal microRNAs in oral lichen planus patients

OBJECTIVE

Oral lichen planus is a chronic inflammatory oral mucosal disease whose exact cause is unclear and which requires efficient diagnostic and therapeutic strategies. Identification of disease-specific biomarkers in saliva is an easy, quick, and non-invasive approach for molecular diagnosis. This study was designed to examine salivary exosomal microRNAs (miRNAs) that could be candidates for diagnosing and elucidating the pathogenesis of oral lichen planus.

SUBJECTS AND METHODS

We compared miRNA profiles of salivary exosomes of patients with oral lichen planus with those of healthy controls. Saliva samples from 16 patients with oral lichen planus and eight healthy controls were divided into two sets and examined using miRNA microarray analysis and TaqMan quantitative PCR.

RESULTS

The three miRNAs identified (miR-4484, miR-1246, and miR-1290) were further validated. Of these, miR-4484 was significantly upregulated in the salivary exosomes of patients with oral lichen planus.

CONCLUSIONS

This study thus identifies a potential miRNA biomarker for oral lichen planus and provides insight into the functions of miRNAs in the pathogenesis of oral inflammatory diseases.

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.

Review of in situ and invasive penile squamous cell carcinoma and associated non-neoplastic dermatological conditions

Penile carcinoma is a rare genitourinary malignancy in North America and Europe with highest rates recorded in South America, Africa and Asia. Recent classifications have refined the terminology used in classifying intraepithelial/in situ lesions and additionally newer entities have been recognised in the invasive category. While increasing recognition of a bimodal pathway of penile carcinogenesis has facilitated understanding and classification of these tumours, handling and subtyping of penile malignancies presents a challenge to the reporting pathologist, in part due to their rarity. This article reviews the terminology and classification of in situ and invasive carcinomas and their relationship to human papilloma virus status. In addition, associated non-neoplastic dermatological conditions of relevance and appropriate ancillary investigations will be addressed.

IL-1β promotes malignant transformation and tumor aggressiveness in oral cancer

Chronic inflammation, coupled with alcohol, betel quid, and cigarette consumption, is associated with oral squamous cell carcinoma (OSCC). Interleukin-1 beta (IL-1β) is a critical mediator of chronic inflammation and implicated in many cancers. In this study, we showed that increased pro-IL-1β expression was associated with the severity of oral malignant transformation in a mouse OSCC model induced by 4-Nitroquinolin-1-oxide (4-NQO) and arecoline, two carcinogens related to tobacco and betel quid, respectively. Using microarray and quantitative PCR assay, we showed that pro-IL-1β was upregulated in human OSCC tumors associated with tobacco and betel quid consumption. In a human OSCC cell line TW2.6, we demonstrated nicotine-derived nitrosamine ketone (NNK) and arecoline stimulated IL-1β secretion in an inflammasome-dependent manner. IL-1β treatment significantly increased the proliferation and dysregulated the Akt signaling pathways of dysplastic oral keratinocytes (DOKs). Using cytokine antibodies and inflammation cytometric bead arrays, we found that DOK and OSCC cells secreted high levels of IL-6, IL-8, and growth-regulated oncogene-α following IL-1β stimulation. The conditioned medium of IL-1β-treated OSCC cells exerted significant proangiogenic effects. Crucially, IL-1β increased the invasiveness of OSCC cells through the epithelial-mesenchymal transition (EMT), characterized by downregulation of E-cadherin, upregulation of Snail, Slug, and Vimentin, and alterations in morphology. These findings provide novel insights into the mechanism underlying OSCC tumorigenesis. Our study suggested that IL-1β can be induced by tobacco and betel quid-related carcinogens, and participates in the early and late stages of oral carcinogenesis by increasing the proliferation of dysplasia oral cells, stimulating oncogenic cytokines, and promoting aggressiveness of OSCC.

Evaluation of ploidy status using DNA-image cytometry of exfoliated mucosal cells in oral lichen planus

Background:

Oral lichen planus (OLP) is one of the potentially malignant disorders (PMDs) with a malignancy rate of 0.2-2%. Aneuploidy is considered to be one of the important markers for malignant transformation and DNA-image cytometry (DIC) has been successfully employed in oral mucosal PMDs and also in tumors of the cervix, lung and biliary tract.

Aims:

In this study, we intend to assess the ploidy status of exfoliated cells in OLP using DIC.

Materials and Methods:

Exfoliated cells from 48 patients with different subtypes of OLP (reticular, plaque type, erosive and atrophic) and 10 controls were stained using Feulgen reaction and assessed for integrated optical density using image analysis software and the ploidy status was assessed.

Results:

All the patients in the control group and most of the patients (93.5%) who had reticular or plaque type of OLP (29 out of 31) exhibited diploid nuclei in the smears, whereas 11 patients who had erosive or atrophic types of OLP showed aneuploid nuclei.

Conclusions:

The patients with erosive or atrophic types of OLP are at more risk and assessment of ploidy status by exfoliative cytology can be used as an adjuvant for diagnosis.

Brief communication (Original). Trefoil factor expression by immunohistochemistry in patients with oral lichen planus

Background: Oral lichen planus (OLP) is a chronic immune-mediated inflammatory disease that usually causes oral mucosal damage. OLP has been considered to be a potentially malignant disorder associated with an increased risk for oral cancer. Trefoil factors (TFFs) are mainly synthesized by mucin-producing epithelial cells. Expression of TFFs in oral epithelia is thought to be an essential factor in protection against oral mucosal damage. However, very little is known about the connection between tissue damage of oral mucosa in OLP patients and expression of TFFs.

Objectives: To determine levels of TFF expression in oral mucosa from patients with OLP.

Methods: Tissue samples were collected from 35 patients with normal oral mucosa (controls) and 35 patients with OLP. An immunohistochemical method was used to determine the expression of the 3 TFFs (TFF1, 2, and 3) in mucosal tissues of the oral cavity.

Results:TFF2 and TFF3 expression in oral epithelia were significantly decreased in OLP patients (Mann- Whitney U test; P = 0.006, and P = 0.002, respectively). There were no significant differences in TFF1 expression between OLP patients and control subjects.

Conclusion: The present study demonstrated reduced expression of TFF2 and TFF3 in oral epithelia of OLP patients. These outcomes support our previous observations that chronic inflammation may play a major role in downregulation of TFF expression, which may be associated with oral mucosal damage in OLP patients.

Malignant transformation of oral lichen planus by a chronic inflammatory process. Use of topical corticosteroids to prevent this progression?

BACKGROUND

Oral lichen planus is a potentially malignant disorder with a capacity, although low, for malignant transformation. Of all the factors related to the process of malignant transformation, it is believed that the chronic inflammatory process plays a key role in the development of oral cancer. This inflammatory process is capable of providing a microenvironment based on different inflammatory cells and molecules that affect cellular growth, proliferation and differentiation.

OBJECTIVES

The objectives of our study are: to review the available evidence about the possible relationship between the chronic inflammatory process present in oral lichen planus and its malignant transformation, to discuss the potential therapeutic implications derived from this relationship and to study the role that topical corticosteroids play in the control of oral lichen planus inflammation and its possible progression to malignant transformation.

CONCLUSION

The maintenance of a minimum dose of topical corticosteroids could prevent the inflammatory progression of oral lichen planus to oral cancer.

A clinical report of an oral lichen planus associated to epidermoid carcinoma in contact with metallic restorations

The aim of this study was to relate the clinical case of a patient with oral lichen planus (OLP) and a history of epidermoid carcinoma associated with metallic restorations. The etiology of OLP is a mucocutaneous disease, which is poorly understood. Studies point to the potential of malignant transformation of OLP and its association with metallic restorations. The metallic restorations were replaced by crowns with a ceramic covering associated and osseointegrated implants in the edentulous areas. About 1 year later, it was observed a bilateral regression of the tongue lesions. The replacement of metallic restorations can contribute to improvement of OLP.

Comparative evaluation of 5-15-kDa salivary proteins from patients with different oral diseases by MALDI-TOF/TOF mass spectrometry

OBJECTIVES

The present study aimed to determine the potential use of matrix-assisted laser desorption/ionization with time-of-flight/time-of-flight mass spectrometry (MALDI-TOF/TOF MS) for analyzing specific patterns of mass signals of low-molecular-weight proteins in saliva from patients with different oral diseases.

MATERIALS AND METHODS

Unstimulated whole saliva samples were collected from healthy subjects (n = 30) and patients with oral diseases including oral cancer (n = 30), oral lichen planus (n = 30), and chronic periodontitis (n = 30). Proteomic profiles of 5,000-15,000-Da salivary proteins were evaluated by MALDI-TOF/TOF MS. Quantification of mass signals was performed by FlexAnalysis and ClinProTool software.

RESULTS

In oral cancer, the percentages of mass signals at 5,592.26 and 8,301.46 Da were significantly increased as compared with other groups (p = 0.002 and p = 0.030, respectively). In oral lichen planus, the percentages of mass signals at 12,964.55 and 13,279.08 Da were significantly increased as compared with other groups (p < 0.001, and p < 0.001, respectively). In chronic periodontitis, the percentages of mass signals at 5,835.73 and 9,801.83 Da were significantly decreased as compared with other groups (p = 0.003 and p = 0.005, respectively).

CONCLUSIONS

The present study demonstrated a potential use of MALDI-TOF/TOF as a rapid screening method to differentiate one oral disease from others by identifying specific patterns of mass signals in saliva from patients. However, MALDI-TOF/TOF has several limitations regarding the identification of the candidate mass signals.

CLINICAL RELEVANCE

MALDI-TOF/TOF MS can be used as a rapid screening method to differentiate one oral disease from others with a caution concerning peptide identity.

Oral manifestations of hepatitis C virus infection

Extrahepatic manifestations (EHMs) of hepatitis C virus (HCV) infection can affect a variety of organ systems with significant morbidity and mortality. Some of the most frequently reported EHM of HCV infection, involve the oral region predominantly or exclusively. Oral lichen planus (OLP) is a chronic inflammatory condition that is potentially malignant and represents cell-mediated reaction to a variety of extrinsic antigens, altered self-antigens, or super antigens. Robust epidemiological evidence support the link between OLP and HCV. As the virus may replicate in the oral mucosa and attract HCV-specific T lymphocytes, HCV may be implicated in OLP pathogenesis. Sjögren syndrome (SjS) is an autoimmune exocrinopathy, characterized by dryness of the mouth and eyes and a multitude of other systemic signs and symptoms. SjS patients have also an increased risk of non-Hodgkin lymphoma. Patients with chronic hepatitis C do frequently have histological signs of Sjögren-like sialadenitis with mild or even absent clinical symptoms. However, it is still unclear if HCV may cause a disease mimicking SjS or it is directly responsible for the development of SjS in a specific subset of patients. Oral squamous cell carcinoma is the most common oral malignant tumour and at least in some part of the world could be linked to HCV.

Oral lichen planus - retrospective study of 563 Croatian patients

Objectives: To investigate the epidemiological and clinical characteristics of oral lichen planus (OLP) in a group of Croatian patients seen between 2006 and 2012. Study Design: A group of 563 patients with a diagnosis of OLP was retrospectively reviewed in our clinic. Data regarding age, gender, medical history, drugs, smoking, alcohol, chief complaint, clinical type, localization, histology, treatment and malignant transformation were registered. Results: Of the 563 patients, 414 were females and 149 were males. The average age at the diagnosis was 58 (range 11-94). The most common site was buccal mucosa (82.4%). Most of our patients did not smoke (72.5%) or consume alcohol (69.6%). Patients reported oral soreness (43.3%), mucosal roughness (7%), xerostomia (3%), gingival bleeding (2%) and altered taste (0.5%) as the chief complaint, while almost half of them were asymptomatic (44.2%). The most common types of OLP were reticular (64.8%) and erosive (22.9%). Plaque-like (5.7%) atrophic/erythemtous (4.3%) and bullous (2.3%) type were also observed. Malignant transformation rate of 0.7% was recorded. Conclusions: OLP mostly affects non-smoking middle-aged women. Buccal mucosa is the most commonly affected site. In almost half of the cases patients are asymptomatic. In spite of the small risk for malignant transformation all patients should be regularly monitored.

Key words:Oral lichen planus, malignant transformation, epidemiology, retrospective study.

Hepatitis C virus: a silent killer relevant to dentistry

Around 25 years ago, hepatitis C virus (HCV) was identified, and following intense research and tremendous advancements, the infection is now potentially curable and even complete viral eradication is possible. It is also evident that HCV can be involved in some oral disorders, but more research is clearly warranted on oral health of HCV-infected patients. Given the global estimates on HCV epidemic and its likely huge economic impact, primary prevention and secondary prevention are worldwide priorities. However, investments are still insufficient to achieve these goals.

Global DNA methylation: uncommon event in oral lichenoid disease

OBJECTIVES

Accumulating evidence indicates that aberrant DNA methylation is closely related to oral carcinogenesis, and it has been shown that methylation changes might be used as prognostic biomarker in oral squamous cell carcinoma. Oral lichenoid disease (OLD) is the most common oral potentially malignant disorder in our region. The aim of this study was to perform the first wide DNA methylation study in OLD in order to investigate the relevance of DNA methylation changes in this premalignant disorder.

MATERIALS AND METHODS

Two different Illumina microarray platforms, namely the GoldenGate Cancer Panel I and the HumanMethylation27 DNA Analysis BeadChip, were utilized in the discovery phase to interrogate the methylation profile of 59 OLD cases and 9 healthy individuals. Top-ranked genes were further validated by pyrosequencing in a second sample set consisting of 160 OLD and 65 controls.

RESULTS

Our results show that the frequency of aberrant DNA methylation is rare in OLD, and this finding was further corroborated by pyrosequencing in the biological validation.

CONCLUSIONS

These findings reinforce the notion that molecular alterations associated with oral carcinogenesis do not seem to be common events in OLD, which in turn might explain the low rate of malignization of this disorder.

Cytomorphometric analysis of exfoliated cells in oral lichen planus

BACKGROUND

Tumors are distinguished from normal tissues partly by their pronounced variability of cellular and nuclear dimensions. Therefore, such factors may be an indicator to assess whether the cells are malignant or not. Exfoliative cytology is a reliable tool in assessing such changes in the uterine cervix and has been used in the oral cavity also with success. The aims and objectives of the following study were to evaluate the malignant changes by assessing the quantitative parameters such as cytoplasmic diameter, cytoplasmic perimeter and cytoplasmic area (CD, CP, CA) and nuclear diameter, nuclear perimeter and nuclear area (ND, NP, NA) and cytoplasmic to nuclear ratio in the exfoliated cells of various subtypes of oral lichen planus (OLP) using cytomorphometry.

MATERIALS AND METHODS

Oral exfoliated cells from nineteen cases of histologically proven OLP (1 atrophic, 13 reticular, 4 erosive and 1 plaque) and ten controls with healthy mucosa were taken and stained by Feulgen-Rossenback reaction and cytomorphometric analysis was performed using an image analysis software. The parameters taken into account were CD, CP, CA and ND, NP, NA. Furthermore CA/NA was calculated. The parameters were statistically analyzed using the t-test.

RESULTS

Cytomorphometric analysis of all the parameters showed no significant difference between the control group and the reticular/plaque subtypes, whereas statistically significant (P < 0.05) differences was obtained between the control group and the atrophic/erosive subtypes group when compared using t-test.

CONCLUSIONS

The cytomorphometric analysis of OLP shows that erosive/atrophic subtypes of OLP are at more risk and exfoliative cytology and cytomorphometry can be used as a tool to assess the malignant changes.