Oral Leukoplakia as It Relates to HPV Infection: A Review

The Follow-Up Necessity in Human Papilloma Virus-Positive vs. Human Papilloma Virus-Negative Oral Mucosal Lesions: A Retrospective Study

Human papilloma virus (HPV) is known as the main cause of cervical cancer. Data also indicate its role in head-neck cancer, especially oropharyngeal cancer. The correlation between high-risk HPV and oral cancer is still controversial. HPV-related lesions of the oral cavity are frequent and, in most cases, benign. The primary aim of this study was to establish if there is a different follow-up necessity between HPV-positive compared to HPV-negative oral lesions. The secondary aim was to evaluate the recurrence of HPV-related lesions. All patients who underwent a surgical procedure of oral biopsy between 2018 and 2022, with ulterior histopathological examination and HPV typing, were examined. A total of 230 patients were included: 75 received traumatic fibroma as diagnosis, 131 HPV-related lesions, 9 proliferative verrucous leukoplakia, and 15 leukoplakia. The frequency and period of follow-up varied in relation to HPV positivity and diagnosis. This study confirms what has already been reported by other authors regarding the absence of recommendations of follow-up necessity in patients with oral mucosal lesions. However, the data demonstrate that there was a statistically significant difference in the sample analyzed regarding the follow-up of HPV-positive vs. HPV-negative patients. It also confirms the low recurrence frequency of HPV-related oral lesions.

The global prevalence of oral leukoplakia: a systematic review and meta-analysis from 1996 to 2022

BACKGROUND

Oral leukoplakia(OLK) is a common oral potentially malignant disorder. The global prevalence of solely OLK was published in 2003, while the prevalence varied among different studies. In recent years, large-scale summary and definition-related analyses obtain insufficient attention. This study aimed to perform a systematic review of prevalence studies of oral leukoplakia and assess predisposing factors of its occurrence.

METHODS

The search terms ("Oral leukoplakia" OR OLK OR leukoplakia) AND (prevalence OR incidence OR epidemiology) were searched in databases (Pubmed, Embase, Scopus, and Web of Science) for OLK studies published from January 1996 until December 2022. The estimated prevalence calculation and risk of bias analysis used STATA 16.0.

RESULTS

We obtained 69 studies, including 1,263,028 participants, from 28 countries, and 6 continents. The prevalence was 1.39%, varying from 0.12 to 33.33%. The overall pooled estimated prevalence of OLK was 2.23% for population-based studies, 1.36% for clinic-based population studies, and 9.10% for specific populations. The pooled prevalence in different continents ranged from 0.33 to 11.74% with a statistical difference in the population-based calculation. The estimated prevalence of OLK was higher in males than in females. Those who smoked and consumed alcohol had a higher prevalence than those who did not.

CONCLUSION

Combining data from 69 published studies, the prevalence of OLK was determined as 1.39% and the pooling estimated global prevalence was 3.41%. The prevalence was relatively consistent and stable across different continents and different definitions. A higher pooled estimated prevalence was found among males, those aged over 60 years old, smokers, and alcohol consumers. The results from the included studies in this systematic review revealed that the prevalence was relatively consistent and stable across various definitions and continents, which may help in developing global treatment and prevention strategies for oral leukoplakia.

Salivary HPV infection in healthy people

Introduction

In recent years, interest in human papillomavirus infections as a causative factor in epithelial cancer development has grown. Literature indicates that HPV involvement in malignant transformations in oral mucosa can vary significantly, from 0 up to 87%. The aim of our study was to detect the prevalence of salivary HPV infection among generally healthy adults.

Materials and Methods

The examination involved 139 patients, from whom 139 whole, 1.5ml saliva samples were obtained. HPV DNA was detected by the nested PCR technique. To visualize the PCR products electrophoresis reactions were carried out.

Results

Sample analysis showed that DNA for HPV was detected in 14 patients: 11 positive results were obtained from men, and 3 from women. This yields a high infection rate: 10.07%.

Conclusions

The HPV prevalence in the male group was more than twice as high as in the female group. Also, subclinical oral HPV infection was detected more frequently in young (19–39 years old) and older (=>60 years old) adults.

Oral leukoplakia: A review of clinical features and trends in management

Introduction: Oral potentially malignant disorders (OPMD) conisit of the group of diseases of great importance for dentists. Oral leukoplakia (OL) has long been the subject of debate by numerous researchers. A common etiologic factor is tobacco, which is associated with oral cancer. The aim of the study is to indicate the severity of the lesion, the most common clinical characreistics and localization. The prevalence of leukoplakia in the world is 2.6% with a rate of malignant conversion ranging from 0.1% to 17.5%. Literature data about the prevalence and annual rate of malignant transformation, approximately 2%, indicate that these changes should be taken seriously and regularymonitored Conclusion: Occurate diagnosis provides the key to preventing to malignant transformation. Various medical and surgical treatment modalities for this lesion have been described. This article highlights various trends in the diagnosis and treatment of oral leukoplakia.

The Role of Human Papilloma Virus in Dictating Outcomes in Head and Neck Squamous Cell Carcinoma

The Human Papilloma Virus (HPV) is an oncogenic virus which is associated with the development of head and neck squamous cell carcinoma (HNSCC), predominantly within the oropharynx. Approximately 25% of oropharyngeal squamous cell carcinoma (OPSCC) cases worldwide are attributable to HPV infection, with an estimated 65% in the United States. Transmission is via exposure during sexual contact, with distinctive anatomical features of the tonsils providing this organ with a predilection for infection by HPV. No premalignant lesion is identifiable on clinical examination, thus no comparative histological features to denote the stages of carcinogenesis for HPV driven HNSCC are identifiable. This is in contrast to HPV-driven cervical carcinoma, making screening a challenge for the head and neck region. However, HPV proffers a favorable prognosis in the head and neck region, with better overall survival rates in contrast to its HPV negative counterparts. This has resulted in extensive research into de-intensifying therapies aiming to minimize the morbidity induced by standard concurrent chemo-radiotherapy without compromising efficacy. Despite the favorable prognosis, cases of recurrence and/or metastasis of HPV positive HNSCC do occur, and are linked with poor outcomes. HPV 16 is the most frequent genotype identified in HNSCC, yet there is limited research to date studying the impact of other HPV genotype with respect to overall survival. A similar situation pertains to genetic aberrations associated in those with HPV positive HNSCC who recur, with only four published studies to date. Somatic mutations in TSC2, BRIP1, NBN, TACC3, NFE2l2, STK11, HRAS, PIK3R1, TP63, and FAT1 have been identified in recurrent HPV positive OPSCC. Finding alternative therapeutic strategies for this young cohort may depend on upfront identification of HPV genotypes and mutations which are linked with worse outcomes, thus ensuring appropriate stratification of treatment regimens.

Judgment and decision-making in clinical dentistry

The development of clinical judgment and decision-making skills is complex, requiring clinicians—whether students, novices, or experienced practitioners—to correlate information from their own experience; from discussions with colleagues; from attending professional meetings, conferences and congresses; and from studying the current literature. Feedback from treated cases will consolidate retention in memory of the complexities and management of past cases, and the conversion of this knowledge base into daily clinical practice. The purpose of this narrative review is to discuss factors related to clinical judgment and decision-making in clinical dentistry and how both narrative, intuitive, evidence-based data-driven information and statistical approaches contribute to the global process of gaining clinical expertise.

Oral HPV16 Prevalence in Oral Potentially Malignant Disorders and Oral Cavity Cancers

The role of human papillomavirus type 16 (HPV16) in oral potentially malignant disorders (OPMD) and oral cavity carcinoma (OC) is still under debate. We investigated HPV16 prevalence in unstimulated saliva, oral rinse samples, oral swabs and tumour biopsies collected from OPMD (n = 83) and OC (n = 106) patients. HPV16 genotype, viral load, physical status (episomal vs. integrated) and tumour p16INK4a expression were determined. Oral HPV16 prevalence was higher in OC than in OPMD, but this difference was not statistically significant (7.5% (8/106) versus 3.6% (3/83), odds ratio (OR): 2.18, 95% confidence interval (CI): 0.56, 8.48, p = 0.26). There was a significant association (p < 0.05) between oral HPV16 infection and heavy tobacco consumption. Real-time PCR results indicated that no integration events occurred in either OPMD or OC cases based on the HPV16 E2/E6 ratio. HPV16 positive OPMD and OC patients had similar HPV16 E2 and E6 viral loads. The inter-rater agreement between tumour p16INK4a expression and oral HPV16 infection was considered as fair (k = 0.361) for OC. Our data suggest that the involvement of HPV16 in oral carcinogenesis is limited.

CD1a+ and CD207+ cells are reduced in oral submucous fibrosis and oral squamous cell carcinoma

Background

The objective of this study investigated the distribution of immature dendritic cells (DCs), Langerhans cells and plasmacytoid DCs in oral submucous fibrosis (OSMF), OSMF associated with oral squamous cell carcinoma (OSMF-OSCC), oral leukoplakia (OL), and oral squamous cell carcinoma (OSCC).

Material and Methods

Fourteen cases of OSMF, 9 of OSMF-OSCC, 8 of OL¸ 45 of OSCC and 8 of normal epithelium were retrospectively retrieved and their diagnoses confirmed. Immunoreactions against CD1a, CD207 e CD303 were performed and the number of positive cells quantified.

Results

A significant decrease of CD1a+ was found in OSMF (p≤0.05), OSMF-OSCC (p ≤ 0.01), and OSCC (p ≤ 0.001) when compared to normal epithelium. For CD207+ the significance decrease was observed in OSMF-OSCC (p ≤ 0.05), and OSCC (p ≤ 0.01) when compared with normal epithelium, and in OSMF when compared with OL (p ≤ 0.05). There was no significant difference for CD303, but increased in CD303+ was observed in OSCC when compared with normal epithelium.

Conclusions

The decrease in the number of CD1a+ and CD207+ cells may be associate to the development of oral OSCC, and in OPMDs they might be indicators of malignant transformation.

Key words:Premalignant lesions, oral submucous fibrosis, oral squamous cell carcinoma, immune response.

Role of Chemiluminescence examination as non-invasive diagnostic tool in early detection of Leukoplakia

OBJECTIVES

To assess the efficacy of Chemiluminescent light (Vizilite plus) in enhancing visualization and its ability to highlight Leukoplakia lesion.

MATERIAL AND METHODS

This was a cross-sectional study done on 40 study subjects. Subjects were inducted into the study irrespective of age and sex based on the specific inclusion and exclusion criteria. The lesion parameters like the location of the lesion, the shape of lesion, the size, the extent, borders and the presence or absence of any adjacent satellite lesions were assessed under Incandescent light followed by Toluidine blue and Vizilite plus examinations. Histopathological examination results were considered as the gold standard and TBLU and CHEM outcomes were compared to them.

RESULTS

Vizilite plus examination method was most effective in assessing the size, borders and shape of the lesions followed by Toluidine blue and Incandescent light examinations. Toluidine blue and Vizilite plus examination methods demonstrated the sensitivity of 100% and specificity of 97.3%. They also demonstrated PPV of 100% and NPV of 75% with reliable accuracy of 97.5%.

CONCLUSION

Chemiluminescent light is a stepping stone and has the potential to revolutionize the diagnostic protocol for patients with potentially premalignant lesions. The device can be used as a general oral mucosal examination system and may in particular improve the visualization of potentially premalignant lesions.

In situ delivery of corticosteroids for treatment of oral diseases

In many mucocutaneous disorders, corticosteroids therapy is currently central. Systemic therapy is restricted to severe disorders whereas topical applications are considered as the first-line treatment. The oral cavity environment, the medication form and other factors related to the delivery method are key factors for the therapy efficiency and effectiveness. Current marketed medications are not able to avoid wrong drug exposure and scarce patients' compliance. Innovative in situ delivery systems are able to prolong the drug retention time on the mucosa and to avoid the drawbacks of conventional formulations. This review is intended to give a general overview of oral mucocutaneous pathologies and highlight the potential of new technologies in designing innovative delivery systems able to release corticosteroids in situ for the treatment of various oral cavity disorders.

HPV infection in the oral cavity: epidemiology, clinical manifestations and relationship with oral cancer

Purpose

The aim of this paper is to describe epidemiology and clinical manifestations of oral infection by Human papillomavirus (HPV), with particular attention to potential malignant lesions.

Materials and methods

A systematic review of the literature was conducted to describe the state of the art about HPV infection in oropharyngeal mucosa and its modalities of transmission, with particular attention to possible simultaneous infection in multiple anatomic sites. The aspects of prevention and control of infection by administering vaccines and the diffusion of sexual education campaigns are discussed also. Therapeutic protocols are also described where necessary.

Results

In recent years there has been a growing interest in HPV oral medicine, suggesting a role of such a family of viruses in the development of neoplasms of the oropharyngeal district as well as of the uterine cervix. Even if the mass media have increasingly faced the problem, causing frequent alarming among patients, the dentist therefore needs a complete and up-to-date knowledge of this infectious condition that is one of the most common causes of sexually transmitted mucous membrane infections (e.g. genital, anal and oral).

Conclusions

Recent studies about HPV infection are a basic requirement in order to promote the health of patients and provide them with the most exhaustive indications from dentists.

Oral leukoplakia and proliferative verrucous leukoplakia: a review for dental practitioners

Objectives To provide an overview of the current thinking in terms of the diagnosis and management of oral leukoplakia and proliferative verrucous leukoplakia as relevant to general dental practitioners.Data sources, data selection, data extraction, data synthesis We searched the MEDLINE Ovid, EMBASE databases and the Cochrane Library, (1990 to 16 April 2017), restricting our search to English language with the following key words: leukoplakia, white patch, proliferative verrucous leukoplakia, precancerous lesion, premalignant lesions, potentially malignant oral conditions and potentially malignant oral disorders. The two authors selected key papers and engaged in collaborative data extraction and synthesis of the selected reference material.Conclusions General dental practitioners (GDPs) are likely to encounter patients with a known or yet undiagnosed oral leukoplakia in their clinical practice. The diagnosis is clinically based as there are no pathognomonic histopathological features. The definition of leukoplakia has evolved over the years. The importance of recognition and appropriate management relating to this condition is described particularly as it is one of the oral potentially malignant lesions. The inferred increased risk of malignant transformation is well documented however controversy still persists in terms of the appropriate management for these lesions. Proliferative verrucous leukoplakia is a recalcitrant, often widespread and multifocal distinct type of leukoplakia. It is considered to have a high rate of malignant transformation with implications in terms of lifelong monitoring both clinically and histopathologically. A high index of suspicion is important for general dental practitioners in order to identify such lesions that would require onward referral for further investigation and management.

Association between oral leukoplakia and risk of upper gastrointestinal cancer death: A follow-up study of the Linxian General Population Trial

Background

This study was conducted to explore the association between oral leukoplakia (OL) and the risk of upper gastrointestinal cancer death in the Linxian General Population Trial Cohort.

Methods

A prospective cohort study of the Linxian General Population Trial Cohort was performed. Participants with OL were treated as an exposed group, and the remainder was selected as a control group. All subjects were followed monthly by village health workers and reviewed quarterly by the Linxian Cancer Registry. Hazard ratios (HRs) and 95% confidence interval (CIs) were evaluated using proportional hazard and proportional subdistribution hazard models, respectively.

Results

Over a median of 27 years of observation, 29 476 subjects were followed‐up. A total of 17 473 deaths occurred, including 2345 esophageal squamous cell carcinoma (ESCC), 1139 gastric cardia carcinoma, and 506 gastric non‐cardia carcinoma deaths. Significant increased ESCC mortality was observed in subjects with OL (exposed 9.66% vs. unexposed 7.39%; P < 0.0001). Furthermore, subjects with OL had a 22% higher risk of death from ESCC (HR 1.22, 95% CI 1.10–1.34; P = 0.0001) after adjusted covariates. In subjects aged ≤52 at the baseline, OL was significantly associated with an elevated risk of ESCC mortality (HR 1.32, 95% CI 1.13–1.54; P = 0.0005). No significant associations were observed for gastric cardia carcinoma and non‐cardia carcinoma mortality.

Conclusions

OL may increase the risk of ESCC mortality, especially in the younger population. These associations should be investigated in further studies.

Human papillomavirus infection in oral potentially malignant disorders and cancer

Human papillomavirus (HPV) infects keratinocytes in the mucosa or skin, and persistent infection with HPV may lead to premalignant lesions and invasive cancer, especially cervical cancer. It has also been hypothesized that HPV infection is an etiological factor of oral squamous cell carcinoma and oral precancerous disorders such as lichen planus, leukoplakia, and erythroplakia. A high percentage of HPV in oral lesions supports the possible viral contribution, but an association of HPV infection with these lesions remains to be established. The current paper will update the latest progress of HPV infection in several oral potentially malignant disorders and oral squamous cell carcinoma and discuss the impact of HPV infection on the progression of oral potentially malignant disorders.

Malignant Transformation in Leukoplakia and Its Associated Factors in Southern Iran: A Hospital Based Experience

BACKGROUND

We evaluated factors that affect malignant transformation of leukoplakia in a sample of the Iranian population.

METHODS

The records of patients with a clinical diagnosis of leukoplakia during a 20-year period from 1989-2009 referred to two of the largest referral centers in southern Iran were studied. Patients that developed malignant transformation were compared with patients that did not have malignant changes.

RESULTS

Of 522 patients, female patients, those over 50 yr old and with lesions located on the tongue had the highest rate of malignant changes. Female patients with malignant changes were mostly non-smokers (76.4%), while male patients with malignant changes were mostly smokers (63.8% in non-smokers) (P<0.001). In our univariate analysis, male sex and smoking showed lower chances for malignant transformation (OR: 0.57; CI=0.397-0.822 and OR: 0.025; CI=0.141-0.299, respectively), while age above 50 was a risk factor for malignant transformation (OR: 3.57; CI=2.32-5.42). In the multivariate analysis, smoking (OR: 0.317; 95% CI=0.16-0.626) and morphological presentation as erythroplakia (OR: 0.025; 95% CI=0.005-0.131) had low chances for developing malignant changes, while site of lesion on the tongue (OR: 774; 95% CI=60-9838) and morphological presentation as erythroleukoplakia (OR: 6.26; 95% CI=3.16-12.38) were a risk factor for developing malignant changes.

CONCLUSION

A follow-up program and further work-up should be considered for Iranian patients who have a leukoplakia lesion that is flat and are white patch or plaques with red components, in addition for patients who have lesions located on the tongue and for nonsmokers who develops leukoplakia lesions.

Evaluation of Different Laser-Supported Surgical Protocols for the Treatment of Oral Leukoplakia: A Long-Term Follow-Up

PURPOSE

The aim of this study was to evaluate the long-term success rate of oral leukoplakia treatments by using different laser-supported surgical protocols.

PATIENTS AND METHODS

Overall, 2347 diagnosed homogeneous oral leukoplakias were treated with CO₂ laser and were included in this study. Different surgical protocols (P) were used: P1 (SV = superficial scanning) was a complete superficial vaporization of the leukoplakia by a scanning mode in two passages respecting an overlapping. Only the visible white area was treated in one surgical session independently of the lesion size. P2 (CR1x1) was a complete excision of the lesions until a tissular depth of 1 mm and 1 mm of surrounding healthy-like tissue were attained. The visible white area was treated in one surgical session independently of the lesion size. P3 (CR1x3) was a complete excision of the lesions until a minimum tissue depth of 1 mm and 3 mm of surrounding healthy-like tissue were obtained. The visible white area was treated in one surgical session independently of the lesion size. P4 (PR1x3) was similar to the third one, but for patient comfort, the large lesions of leukoplakias (lesion size higher than 20 mm), the complete surgical excision of the leukoplakia was performed in multiple sessions that were spaced by 1 month (partial surgical removal of 10 mm per session). All patients were recalled at 2 and 8 weeks after surgery, and then every 2 months during the first year, every 4 months during the second year, and once a year for the follow-up period of 6 years. A biopsy was done once a year during the follow-up period in the surgical site when needed. The control consisted of checking the nature and the aspect of the healed mucosa to exclude an eventual recurrence of leukoplakia.

RESULTS

The percentage of permanent success after 6 years of follow-up was 5.7%, 69.7%, 97.8%, and 71.9%, respectively, for the first surgical protocol (SV), the second (CR 1 × 1), the third (CR 1 × 3), and the fourth (PR 1 × 3). The appearance of malignant transformation after laser treatment (during the follow-up period of 6 years) was 20%, 1%, and 0.2%, respectively, for the groups treated by the following protocols: 1 (SV), 2 (CR 1 × 1), and 4 (PR 1 × 3). Only in the third group CR1x3, no dysplasia or malignant transformation was noted. On the contrary, the appearance of malignant transformation in failed treated cases was 21.21% for the protocol 1 (SV), 3% for the protocol 2 (CR 1 × 1), and 0.6% for the protocol 4 (PR 1 × 3).

CONCLUSIONS

The results of this long-term follow-up of treated patients with oral homogeneous leukoplakias pointed out that the surgical laser protocol respecting the complete excision of leukoplakias, in one session, by the removal of a minimum of 1 mm in lesion depth and 3 mm of surrounding healthy-like tissues (CR 1 × 3) offers significantly the highest success rate.

Expression of Human Papillomavirus DNA and p53 Polymorphisms through Polymerase Chain Reaction in Normal Mucosa and Oral Leukoplakia Individuals with Deleterious Oral Habits

Context:

Oral leukoplakia (OL) is a well-recognized precancerous lesion with various etiological factors. Most commonly deleterious oral habits such as tobacco smoking and viral etiologies mainly human papillomavirus (HPV) play an important role. p53 polymorphisms mostly homozygous Arginine (Arg) allele has a greater risk of degradation by HPV. Hence, HPV infection and p53 polymorphisms may act as synergistic factors for increased the risk of malignant transformation in oral precancerous lesions.

Aims:

The aim of this study is to evaluate the risk of OL and its malignant transformation due to infection by HPV and p53 polymorphisms in the oral biopsy samples through polymerase chain reaction (PCR).

Subjects and Methods:

A total of 40 individuals were involved– 10 individuals were controls without deleterious habits, 15 were controls with deleterious habits, and 15 were with histologically confirmed OL individuals with deleterious habits. PCR and restriction fragment length polymorphism using sma1 enzyme were carried out to evaluate the expression of HPV and p53 polymorphisms.

Statistical Analysis Used:

Chi-square test, Fischer's exact t-test, and odds ratio.

Results:

(1) HPV DNA expression was higher in Leukoplakia individuals than controls. (2) p53 genotype with homozygous Arg was more in HPV-infected individuals.

Conclusions:

To conclude HPV infected OL cases were mostly with Arg/Arg type of p53 polymorphism.

Potentially malignant oral lesions: clinicopathological correlations

Objective

To determine the incidence of potentially malignant oral lesions, and evaluate and correlate their clinical and pathological aspects.

Methods

The sample consisted of cases clinically diagnosed as oral leukoplakia, oral erythroplakia, erythroleukoplakia, actinic cheilitis, and oral lichen planus treated at a diagnostic center, between May 2012 and July 2013. Statistical tests were conducted adopting a significance level of 5% (p≤0.05).

Results

Out of 340 patients, 106 (31.2%) had potentially malignant oral lesions; and 61 of these (17.9%) were submitted to biopsy. Actinic cheilitis was the most frequent lesion (37.5%) and the lower lip was the most affected site (49.6%). Among 106 patients in the sample, 48 (45.3%) reported nicotine consumption, 35 (33%) reported alcohol intake and 34 (32.1%) sun exposure while working. When clinical and histopathological diagnoses were compared, oral erythroplakia and atypical ulcer were the lesions that exhibited greater compatibility (100% each).

Conclusion

In most cases, clinical and histopathological diagnoses were compatible. An association between the occurrence of erythroplakia, leukoplakia and erythroleukoplakia with smoking was observed. Similarly, an association between actinic cheilitis and sun exposure was noted. Erythroleukoplakia presented the highest malignancy grade in this study. Finally, dental surgeons should draw special attention to diagnosis of potentially malignant oral lesions, choose the best management, and control the lesions to avoid their malignant transformation.

Expression of human telomerase reverse transcriptase protein in oral epithelial dysplasia and oral squamous cell carcinoma: An immunohistochemical study

Background:

Telomerase is an RNA-dependent DNA polymerase that synthesizes TTAGGG telomeric DNA sequences and almost universally provides the molecular basis for unlimited proliferative potential. The telomeres become shorter with each cycle of replication and reach a critical limit; most cells die or enter stage of replicative senescence. Telomere length maintenance by telomerase is required for all the cells that exhibit limitless replicative potential. It has been postulated that reactivation of telomerase expression is necessary for the continuous proliferation of neoplastic cells to attain immortality. Use of immunohistochemistry (IHC) is a useful, reliable method of localizing the human telomerase reverse transcriptase (hTERT) protein in tissue sections which permits cellular localization. Although there exists a lot of information on telomerase in oral cancer, little is known about their expression in oral epithelial dysplasia and their progression to oral squamous cell carcinoma (OSCC) compared to normal oral mucosa. This study addresses this lacuna.

Aims:

To compare the expression of hTERT protein in oral epithelial dysplasia and OSCC with normal oral mucosa by Immunohistochemical method.

Subjects and Methods:

In this preliminary study, IHC was used to detect the expression of hTERT protein in OSCC (n = 20), oral epithelial dysplasia (n = 21) and normal oral mucosa (n = 10). The tissue localization of immunostain, cellular localization of immunostain, nature of stain, intensity of stain, percentage of cells stained with hTERT protein were studied. A total number of 100 cells were counted in each slide.

Statistical Analysis:

All the data were analyzed using SPSS software version 16.0. The tissue localization, cellular localization of cytoplasmic/nuclear/both of hTERT stain, staining intensity was compared across the groups using Pearson's Chi-square test. The mean percentage of cells stained for oral epithelial dysplasia, OSCC and normal oral mucosa were compared using analysis of variance (ANOVA). A P < 0.05 was considered to be statistically significant.

Results:

The mean hTERT positive cells in the study groups were as follows, 62.91% in normal oral mucosa samples, 77.06% in oral epithelial dysplasia cases, and 81.48% in OSCC. In 61.9% of oral epithelial dysplasia and 65% of OSCC in our study, staining was visualized within the nucleus predominantly in the dot like pattern. There was a statistically significant difference in the nature of nuclear stain between oral epithelial dysplasia and OSCC (P = 0.023).

Conclusions:

Our results suggests that the mean percentage of cells showing hTERT expression steadily increased from normal oral mucosa to oral epithelial dysplasia to OSCC. The steady trend of increase in the percentage of cells was evident in different grades of oral epithelial dysplasia group and OSCC. The nature of hTERT staining did show variations among the three groups and promise to be a potential surrogate marker for malignant transformation. Further studies using IHC on larger sample size and clinical follow-up of these patients will be ascertaining the full potential of hTERT as a surrogate marker of epithelial transformation.

Unilateral corneal leukoplakia without limbal involvement

Purpose

Leukoplakia is the term given to a white patch or plaque that is found mainly on the oral mucus membrane. It can occasionally be seen on the corneal surface. We report our clinical and histopathological findings in a case of unilateral corneal leukoplakia.

Methods

A 26-year-old woman was referred to our hospital because of a white patch on her right cornea that continued to expand. She first noticed the white patch when she was 20 years old, and the white patch had expanded to cover the pupillary area affecting her vision. After plastic surgery on both eyelids for bilateral entropion to alleviate the pain caused by the eyelashes rubbing the cornea, the white corneal patch decreased in size. Because of this reduction, we performed surgery to remove the patch with microforceps under topical anesthesia. The plaque was removed easily and completely, and submitted for histopathological examination.

Results

Histopathological examination showed that the specimen had characteristics of epidermis with a basal cell layer, spinous cell layer, granular cell layer, and horny layer with hyperkeratosis. She was diagnosed with leukoplakia of the corneal surface. The basic structure of the squamous cell layer was preserved, and there were no signs of metaplasia. Six months after the removal of the leukoplakia, no recurrence was seen and her corrected decimal visual acuity recovered to 1.0.

Conclusion

Our case of unilateral corneal leukoplakia without limbal involvement was most likely caused by chronic irritation of the cornea by the eyelashes. Although it was totally removed with good recovery of vision, we continue to follow the patient because of the potential of malignant transformation.

Techniques for early diagnosis of oral squamous cell carcinoma: Systematic review

Background and objectives

The diagnosis of early oral potentially malignant disorders (OPMD) and oral squamous cell carcinoma (OSCC) is of paramount clinical importance given the mortality rate of late stage disease. The aim of this study is to review the literature to assess the current situation and progress in this area.

Material and Methods

A search in Cochrane and PubMed (January 2006 to December 2013) has been used with the key words “squamous cell carcinoma”, “early diagnosis” “oral cavity”, “Potentially Malignant Disorders” y “premalignant lesions”. The inclusion criteria were the use of techniques for early diagnosis of OSCC and OPMD, 7 years aged articles and publications written in English, French or Spanish. The exclusion criteria were case reports and studies in other languages.

Results

Out of the 89 studies obtained initially from the search 60 articles were selected to be included in the systematic review: 1 metaanalysis, 17 systematic reviews, 35 prospective studies, 5 retrospective studies, 1 consensus and 1 semi-structured interviews.

Conclusions

The best diagnostic technique is that which we have sufficient experience and training. Definitely tissue biopsy and histopathological examination should remain the gold standard for oral cancer diagnose. In this systematic review it has not been found sufficient scientific evidence on the majority of proposed techniques for early diagnosis of OSCC, therefore more extensive and exhaustive studies are needed.

Key words: Squamous cell carcinoma, early diagnosis, oral cavity, potentially malignant disorders, premalignant lesions.

Oral Human Papillomavirus Infection and Oral Lesions in HIV-Positive and HIV-Negative Dental Patients

We evaluated the risk factors associated with oral human papillomavirus (HPV) infection and oral lesions in 161 human immunodeficiency virus (HIV)-positive patients and 128 HIV-negative patients presenting for oral examination at 2 urban healthcare centers. Patients were interviewed on risk factors and provided oral-rinse samples for HPV DNA typing by polymerase chain reaction. Statistical associations were assessed by logistic regression. Oral HPV was prevalent in 32% and 16% of HIV-positive patients and HIV-negative patients, respectively, including high-risk HPV type 16 (8% and 2%, respectively; P = .049) and uncommon HPV types 32/42 (6% and 5%, respectively; P = .715). Among HIV-negative patients, significant risk factors for oral HPV included multiple sex partners (≥21 vs ≤5; odds ratio [OR], 9.1; 95% confidence interval [CI], 1.7-49.3), heavy tobacco smoking (>20 pack-years vs none; OR, 9.2; 95% CI, 1.4-59.4), and marijuana use (OR, 4.0; 95% CI, 1.3-12.4). Among HIV-positive patients, lower CD4(+) T-cell count only was associated with oral HPV detection (≤200 vs ≥500 cells/mm(3); OR, 4.5; 95% CI, 1.3-15.5). Detection of high-risk HPV was also associated with concurrent detection of potentially cancerous oral lesions among HIV-negative patients but not among HIV-positive patients. The observed risk factor associations with oral HPV in HIV-negative patients are consistent with sexual transmission and local immunity, whereas in HIV-positive patients, oral HPV detection is strongly associated with low CD4(+) T-cell counts.

Clinical characteristics of Japanese oropharyngeal squamous cell carcinoma positive for human papillomavirus infection

CONCLUSION

Human papillomavirus (HPV)-related oropharyngeal squamous cell carcinoma (OPSCC) is considered to be a distinct entity in Japan. The combination of both HPV-DNA sequencing analysis and immunohistochemistry (IHC) for p16(INK4A) is useful to discriminate the OPSCC patients with a better prognosis from other cases, especially in the advanced stage. Surgical treatment is recommended for HPV-negative advanced cancer.

OBJECTIVE

The number of HPV-related OPSCCs has been increasing worldwide. However, the incidence and prognostic significance of this cancer in Japan have not yet been fully elucidated.

METHODS

Seventy-seven Japanese patients with OPSCC were enrolled in this study. The prevalence of HPV-DNA was assessed by PCR and sequencing. The expression of p16(INK4A) and p53 was examined by IHC. The clinicopathological parameters and disease-specific survival were analyzed for HPV-positive and -negative patients.

RESULTS

HPV-DNA was detected in 32 patients. Thirty-four patients were p16(INK4A)-positive by IHC. The patients who were positive for HPV infection were significantly younger. Furthermore, in the stage III or IV cases, the 3-year disease-specific survival of the HPV infection-positive group was significantly better than that of the HPV-negative group. Surgical treatment was demonstrated to lead to a good prognosis for the patients with HPV-negative advanced cancer.

The role of human papillomavirus in oral disease

A wide range of human papillomavirus (HPV) genotypes have been detected in oral mucosa. Clinical infections with low-risk genotypes manifest as squamous papilloma, condyloma acuminatum, verruca vulgaris, or multifocal epithelial hyperplasia. Clinical infections with high-risk genotypes have been associated with malignant lesions. The most common genotype isolated from subclinical infection is HPV-16. A causal role for HPV in carcinogenesis of oral squamous carcinoma is minimal. Ongoing vaccination against HPV types 6, 11, 16, and 18 is expected to decrease the spread of infection and decrease the carcinogenic potential of HPV-16 in the oropharynx and oral cavity.

Current views and perspectives on classification of squamous intraepithelial lesions of the head and neck

The current state in the field of classifying oral and laryngeal precursor lesions, as proposed in the WHO 2005 Blue Book is not ideal. The results of various inter-observer studies have shown that the currently used grading systems, with different basic concepts and different terminology, cannot continue to be reliably used in the future. The different etiology of cervical and head and neck precursor lesions requires a classification designed to cater to the specificities of the head and neck region. Trying to harmonize different classifications of the oral and laryngeal precursor lesions, we have proposed four crucial steps to set up a unified classification of squamous intraepithelial lesions (SILs): (a) the classification should contain two grades, low-grade and high-grade lesions and, specifically for the larynx, an additional grade-carcinoma in situ (CIS) which must be separated from high-grade laryngeal SILs; (b) the terminology should be unified; our preference is for the term SIL over squamous intraepithelial neoplasia; (c) all leading morphological criteria for low- and high-grade lesions, as well as for CIS, should be clearly defined; (d) agreement between clinicians and pathologists should be achieved on the most appropriate choice of treatment of different grades of SILs in separate head and neck areas.

MicroRNAs in Head and Neck Cancer

microRNAs (miRs) are small noncoding single-stranded RNAs, about 19–25 nucleotides long. They have been shown to be capable of altering mRNA expression; thus some are oncogenic or tumour suppressive in nature and are regulated by cellular and epigenetic factors. The molecular pathogenic pathway of many cancers has been modified since the discovery of miRs. Head and neck squamous cell carcinoma (HNSCC), the sixth most common cancer in the world, has recently been associated with infection by the human papillomavirus (HPV). miR expression profiles are altered in the transition from dysplasia to carcinoma, with some changes being specific to the underlying risk factor. This difference is particularly significant in HPV-positive HNSCC where host miRs are modulated by the virus, creating a different profile to HPV-negative HNSCC. Saliva, as an easily collected proximal biofluid containing numerous miRs, presents an attractive noninvasive diagnostic tool in detecting HNSCC and determining prognosis. Furthermore, miRs may play a role in the analysis of surgical margins for residual tumour extension and in the development of novel miR-based therapeutic targets and agents.

Diagnostic aids for detection of oral precancerous conditions

Oral cancer has a tendency to be detected at late stage which is detrimental to the patients because of its high mortality and morbidity rates. Early detection of oral cancer is therefore important to reduce the burden of this devastating disease. In this review article, the most common oral precancerous lesions are discussed and the importance of early diagnosis is emphasized. In addition, the most common non-invasive oral cancer devices that can aid the general practitioners in early diagnosis are also discussed.

Oral leukoplakia in a South African sample: a clinicopathological study

OBJECTIVE

This study analysed differences in clinicopathological features of oral leukoplakia in different racial groups in the greater Johannesburg area of South Africa, with emphasis on the black population.

MATERIAL AND METHODS

The retrospective review included cases diagnosed clinically as oral leukoplakia and histologically as hyperkeratosis without dysplasia, hyperkeratosis with mild, moderate or severe dysplasia, and carcinoma in situ from 1990 to 2010. Age, gender, ethnicity, clinical appearance, site of lesion and tobacco smoking habit were recorded.

RESULTS

Fourteen per cent of oral leukoplakia occurred in black South Africans compared with 80% in white South Africans. In contrast to whites, blacks were diagnosed with oral leukoplakia at a younger age; there were more men affected than women; and the proportion of idiopathic leukoplakia was greater. There were significantly more blacks (23%) than whites (13%) with non-homogenous leukoplakia and significantly more whites (51%) than blacks (23%) with dysplastic oral leukoplakia.

CONCLUSION

This study suggests that oral leukoplakia, especially non-homogenous and idiopathic forms affects South African blacks less frequently than white South Africans; and in the former, it occurs more in men and at a younger age. These findings may provide some guidance in establishing screening policies for oral cancer, particularly suited for blacks.