Oral squamous cell carcinoma versus oral verrucous carcinoma: an approach to cellular proliferation and negative relation to human papillomavirus (HPV)

Oral verrucous carcinoma: a diagnostic and therapeutic challenge

BACKGROUND

Verrucous carcinoma is a low-grade variant of squamous cell carcinoma with specific morphologic, cytokinetic and clinical features. Despite low mitotic activity and slow growth, it can infiltrate adjacent tissues in advanced stages but does not metastasize. The most frequently affected site is the oral cavity. The following article provides latest updates in the etiology, clinical presentation, diagnostics and treatment options in oral verrucous carcinoma and discusses the existing dilemmas linked to this unique malignancy.

CONCLUSIONS

Oral verrucous carcinoma must be differentiated from conventional squamous cell carcinoma due to its less aggressive behaviour with a more favourable prognosis. Close communication between clinician and pathologist is mandatory for making a correct diagnosis. Primary surgery with negative surgical margins seems to be the most successful treatment. However, management recommendations are not uniform since they are mostly based on case reports and small retrospective case series. Prospective and pooled multi-institutional studies are therefore needed.

Human papillomavirus prevalence in oral and oropharyngeal squamous cell carcinoma in South America: A systematic review and meta-analysis

Some studies have addressed the prevalence of human papillomavirus (HPV) in head and neck cancer in South America; however, no studies have systematically gathered prevalence and conducted a meta-analysis. This study aims to estimate the prevalence of HPV in oral and oropharyngeal squamous cell carcinomas in South America. We performed a systematic review and metaanalysis using the following databases: PubMed, Embase, Lilacs, Medline, Scopus, and Web of Science. Data were extracted and analyzed using random-effects models to estimate the pooled prevalence of HPV. We identified 209 nonduplicated studies, of which 38 were selected. The overall prevalence of HPV was 24.31% (95% CI 16.87-32.64; I2 = 96%, p heterogeneity <0.001). HPV prevalence in oropharyngeal cancer was 17.9% (95% CI 7.6-31.4; I2 = 96%, p heterogeneity <0.001) and that in oral cavity cancer was 23.19% (95% CI 14.94-32.63; I2 = 94%, p heterogeneity <0.001). We found an overall prevalence of HPV in 24.31% of oral and oropharyngeal squamous cell carcinomas in South American patients. The prevalence of HPV was 17.9% for oropharyngeal cancer and 23.19% for oral cavity cancer.

Association of HPV and EBV in Oral Verrucous Squamous Cell Carcinoma and Oral Verrucous Hyperplasia

Objective  Oral verrucous squamous cell carcinoma or oral verrucous carcinoma (OVC) is a rare verrucous variant of oral squamous cell carcinoma (OSCC), which accounts for 2 to 12% of all oral carcinomas. Oral verrucous hyperplasia (OVH) is clinically similar to OVC and has been proposed to be a precursor lesion of OVC. Etiopathogenesis of both lesions is still inconspicuous. Oncogenic viruses such as human papillomavirus (HPV) and Epstein–Barr virus (EBV) have been reported to be associated with some cases of OSCC, and we hypothesized that it may act as a causative agent of these verrucous lesions. This study aimed to investigate frequency of HPV and EBV infections in OVC and OVH.

Material and Methods  Using polymerase chain reaction (PCR), a total of 35 formalin-fixed paraffin-embedded (FFPE) tissue samples, including 27 OVC samples and 8 OVH samples, were investigated for HPV and EBV infection. HeLa and B95-8 cell lines were used as positive controls of HPV and EBV PCR, respectively.

Results  All OVC and OVH samples show a positivity to GAPDH , whereas neither HPV nor EBV PCR products was detected in both OVC and OVH samples.

Conclusions  In summary, our study demonstrated that HPV and EBV are not involved in pathogenesis of OVC and OVH. Other etiologic factors contributing to OVC and OVH need to be further clarified.

Human papillomavirus-16 infection and p16 expression in oral squamous cell carcinoma

Human papillomavirus (HPV) is a possible carcinogenetic factor in oral squamous cell carcinoma (OSCC). Previous studies have reported the prevalence of HPV in patients with OSCC. However, the association between HPV and OSCC remains controversial. The present study aimed to clarify the association between HPV infection, p16 protein expression and the clinicopathological characteristics of OSCC. The expression level of HPV-16E6 mRNA and p16 protein, a known surrogate marker of HPV infection, was investigated in 100 OSCC cases using TaqMan reverse transcription-quantitative PCR and immunohistochemistry staining, respectively. HPV-16E6 mRNA expression level was only detected in one case (1%), and positive expression of p16 was found in 10 cases (10%), including an HPV-positive case. Subsequently, the association between p16 expression level and clinicopathological characteristic factors were analyzed; however, no significant association was found. These results suggested that HPV-16 infection was less likely to cause OSCC in Japan and p16 expression was not a suitable marker for HPV infection in OSCC.

Importance of human papillomavirus infection in squamous cell carcinomas of the tongue in Guangdong Province, China

Objective

Methods

Results

Conclusion

Prevalence of HPV in Oral Squamous Cell Carcinoma in South West India

There are inconsistent reports regarding the role of HPV in the origin and progression of oral squamous cell carcinoma (OSCC). The observed heterogeneity was mainly attributed to the social and cultural habits of the enrolled cases, discrepancies in the nature of samples procured and varying sensitivity of the assays employed for detection of HPV. The objective of this study was to assess the prevalence of HPV in OSCC in South West India. This was a cross sectional study conducted over a period extending from October 2015 to June 2017. This study involved Department of ENT-Head and Neck Surgery and Department of Virology, Manipal Academy of Higher Education. Fifty histologically confirmed oral squamous cell carcinoma patients undergoing wide local excision of the tumour were enrolled for the study. Intraoperatively 4-5 mm of tissue samples were transported in sterile normal saline at 4-80 °C. The primary screening of tissue samples was performed by nested PCR using PGMY09/11 consensus primers and GP5+/6+ consensus primers and TaqMan based real time multiplex PCR for HPV-16, HPV-18, HPV-31 and HPV-45. All samples tested negative for HPV DNA by conventional nested PCR and TaqMan based real-time Multiplex PCR ruling out four common HPV subtypes such as HPV-16, 18, 31, 45. We did not find presence of HPV DNA in the tissues of patients with OSCC from southwest India. However, studies with more geographic representation from other parts of India are required before generalising our findings.

Frequency of HPV in oral cavity squamous cell carcinoma

BACKGROUND

The prevalence of high-risk human papillomavirus (HPV) DNA in cases of oral cavity squamous cell carcinoma (SCC) varies widely. The aim of this study is to investigate the frequency of high-risk HPV DNA in a large Brazilian cohort of patients with oral cavity SCC.

METHODS

Biopsy and resected frozen and formalin-fixed paraffin-embedded specimens of oral cavity SCC were available from 101 patients who were recruited at two Brazilian centres. Stringent measures with respect to case selection and prevention of sample contamination were adopted to ensure reliability of the data. Nested PCR using MY09/MY11 and GP5⁺/GP6⁺ as well as PGMY09/11 L1 consensus primers were performed to investigate the presence of HPV DNA in the tumours. HPV-positive cases were subjected to direct sequencing. Shapiro-Wilk and Student t test were used to evaluate data normality and to compare the means, respectively. Qualitative variables were analysed by logistic regression.

RESULTS

Our results demonstrate that the frequency of high-risk HPV types in oral cavity SCC is very low and is less than 4%. All HPV-positive cases were HPV16. In addition, our results do not show a significant association between the tumour clinical features and the risk factors (tobacco, alcohol and HPV) for oral cavity SCC.

CONCLUSION

In the current study, we observed an overlapping pattern of risk factors that are related to tumour development. This, along with a low frequency of high-risk HPV DNA, supports the findings that HPV is not involved in the genesis of oral cavity SCC in Brazilian population.

Diagnostic Biomarkers in Oral Verrucous Carcinoma: A Systematic Review

Oral verrucous carcinoma (OVC), a low-grade variant of oral squamous cell carcinoma (OSCC), is most frequently seen in the oral cavity. No clear etiology has been found for this lesion, but human papilloma virus, chewing betel nuts, and ultraviolet radiation are suggested as probable causes. Differential diagnosis of OVC is challenging for oral pathologists. The aim of this study was to review the molecular-based approaches for differential diagnosis of OVC. An electronic search was conducted in Medline and Scopus from January 2004 to July 2015 limited to English language publications. Published papers on verrucous carcinoma (VC) were found according to the inclusion and exclusion criteria and analyzed qualitatively. Data extraction were performed according to PRISMA statement. A total of 423 articles were reviewed; out of which, 26 articles completely fulfilled the inclusion criteria. Most of the included studies investigated proliferative and apoptotic biomarkers such as p53 and Ki67. No definite conclusion was drawn for cytoskeletal biomarkers due to variability of factors and lack of significant expression. However, it seems that cytokeratin10 (CK 10) can be useful for differentiation of OVC and benign squamous lesions. Among cell surface and extracellular matrix biomarkers tissue biomarkers, matrix metalloproteinase (MMP)-2, -9, CD31 and CD68 seem to be useful for differentiation of OVC and OSCC and glucose transporter-1 (GLUT-1) can help in differentiation of OVC from oral epithelial dysplasia. Differences among OVC, OSCC and normal epithelium in expression profiles of the investigated biomarkers help in their differential diagnosis; although, clinicohistopathological similarities among verrucous hyperplasia, noninvasive OVC and invasive well-differentiated OSCC make the diagnosis difficult. Further studies are required to better differentiate these oral lesions.

Immunohistochemical Expression of Cyclin B1 in Epithelial Hyperplasia, Dysplasia and Oral Squamous Cell Carcinomas - A Comparative Study

INTRODUCTION

Cyclin B1 is important in the cell cycle progression from G2 to M phase. Cyclin B1 binds to CDC2, which then becomes dephosphorylated and gets relocated to the nucleus, ensuring the transition toward mitosis.

AIM

Over expression of Cyclin B1, has been reported more recently in breast, colon, prostate, oral and esophageal carcinomas. Thus, the aim of the present study was to examine the expression of Cyclin B1 in hyperplasia, dysplasia and Oral Squamous Cell Carcinomas (OSCC).

MATERIALS AND METHODS

A total of 64 histopathologically diagnosed cases of epithelial hyperplasias, dysplastic oral epithelium and OSCC were included in the study. Immunohistochemical procedure was carried out using the monoclonal mouse Cyclin B1 antibody (Clone V-152). The Cyclin B1 positive tumor cells counted were expressed as percentage of positive tumor cells. Nuclear and cytoplasmic labeling index (n&cLI) were calculated. The results were tabulated and statistically analyzed by Kruskal Wallis test- One Way ANOVA and Mann Whitney U- test.

RESULTS

Combined n&cLI was considered only in 28.57% of epithelial hyperplasias, 40.7% of oral epithelial dysplasias and 72% of OSCC showed over expression of Cyclin B1 with p value being 0.029. Cyclin B1 expression was not significantly different between the grades of dysplasia, between the grades of OSCC and between the marginal groups.

CONCLUSION

The present study demonstrates more than 50% of the study group showing less than 20% of nuclear staining. The importance of such variations within a type of lesion requires further investigation, since Cyclin B1 has proved useful in many studies from esophageal and laryngeal squamous cell carcinoma as a prognostic indicator, an indicator of recurrence and as an indicator for tumor sensitivity to radiotherapy. Further studies are to be extended towards evaluating the role of Cyclin B1 as a prognostic indicator.

Oral verrucous carcinoma: From multifactorial etiology to diverse treatment regimens (Review)

Oral verrucous carcinoma (OVC) is a verrucous variant of oral squamous cell carcinoma (OSCC), which accounts for 2-12% of all oral carcinomas with a 5-year survival rate of only approximately 50%. Enormous effort has been dedicated to this cancer, and the past decades have witnessed significant advances in relevant diagnostic and therapeutic approaches. Currently, there exist three challenges from primary sub-fields of research and clinical practice of the cancer, namely multifactorial etiology, complex molecular mechanism, and deficient treatment. This study reviews the existing literature on the cancer, encompassing its etiology, clinical manifestations and pathology, molecular mechanism, diagnosis and differential diagnosis, and treatment. For improved treatment of OVC, multifactorial etiology analysis, incorporation of effective biomarkers for mechanism illustration, and integration of multidisciplinary modalities are expounded, in an attempt to resolve the challenges and to provide a useful guide for future research in the field.

Alcohol and Tobacco Increases Risk of High Risk HPV Infection in Head and Neck Cancer Patients: Study from North-East Region of India

BACKGROUND

Human papilloma virus (HPV) associated Head and Neck Cancers (HNCs) have generated significant amount of research interest in recent times. Due to high incidence of HNCs and lack of sufficient data on high-risk HPV (hr-HPV) infection from North -East region of India, this study was conceived to investigate hr-HPV infection, its types and its association with life style habits such as tobacco, alcohol consumption etc.

METHODS

A total of one hundred and six primary HNC tumor biopsy specimens were collected. These samples were analyzed for hr-HPV DNA (13 HPV types) using hybrid capture 2 (HC2) assay and genotyping was done by E6 nested multiplex PCR (NMPCR).

RESULTS

The presence of hr-HPV was confirmed in 31.13% (n = 33) and 24.52% (n = 26) of the HNC patients by nested multiplex PCR (NMPCR) and HC2 assay respectively. Among hr-HPV positive cases, out of thirteen hr- HPV types analyzed, only two prevalent genotypes, HPV-16 (81.81%) followed by HPV-18 (18.18%) were found. Significant association was observed between hr-HPV infection with alcohol consumption (p <0.001) and tobacco chewing (p = 0.02) in HNC cases. Compared to HPV-18 infection the HPV-16 was found to be significantly associated with tobacco chewing (p = 0.02) habit.

CONCLUSIONS

Our study demonstrated that tobacco chewing and alcohol consumption may act as risk factors for hr-HPV infection in HNCs from the North-East region of India. This was the first study from North-East India which also assessed the clinical applicability of HC2 assay in HNC patient specimens. We suggest that alcohol, tobacco and hr- HPV infection act synergistically or complement each other in the process of HNC development and progression in the present study population.

Prevalence of oral and oropharyngeal human papillomavirus infection in Brazilian population studies: a systematic review

Introduction

Human papillomavirus has been associated with head and neck squamous cell carcinoma. However, there is no conclusive evidence on the prevalence of oral or pharyngeal infection by human papillomavirus in the Brazilian population.

Objective

To determine the rate of human papillomavirus infection in the Brazilian population.

Methods

Systematic review of published articles. Medline, The Cochrane Library, Embase, Lilacs (Latin American and Caribbean Health Sciences) and Scielo electronic databases were searched. The search included published articles up to December 2014 in Portuguese, Spanish and English. A wide search strategy was employed in order to avoid publication biases and to assess studies dealing only with oral and/or oropharyngeal human papillomavirus infections in the Brazilian population.

Results

The 42 selected articles enrolled 4066 patients. It was observed that oral or oropharyngeal human papillomavirus infections were identified in 738 patients (18.2%; IC 95 17.6–18.8), varying between 0.0% and 91.9%. The prevalences of oral or oropharyngeal human papillomavirus infections were respectively 6.2%, 44.6%, 44.4%, 27.4%, 38.5% and 11.9% for healthy people, those with benign oral lesions, pre-malignant lesions, oral or oropharyngeal squamous cell carcinoma, risk groups (patients with genital human papillomavirus lesions or infected partners) and immunocompromised patients. The risk of human papillomavirus infection was estimated for each subgroup and it was evident that, when compared to the healthy population, the risk of human papillomavirus infection was approximately 1.5–9.0 times higher, especially in patients with an immunodeficiency, oral lesions and squamous cell carcinoma. The rates of the most well-known oncogenic types (human papillomavirus 16 and/or 18) also show this increased risk.

Conclusions

Globally, the Brazilian healthy population has a very low oral human papillomavirus infection rate. Other groups, such as at-risk patients or their partners, immunocompromised patients, people with oral lesions and patients with oral cavity or oropharyngeal squamous cell carcinoma have a high risk of human papillomavirus infection.

Prevalence of high-risk human papillomavirus type 16 and 18 in oral and cervical cancers in population from Gujarat, West India

BACKGROUND

Oral and cervical cancers are major malignancies in men and women, respectively, in India. This study evaluated occurrence of human papillomavirus (HPV) 16 and 18 infections in oral and cervical cancers to estimate HPV-associated burden of these cancers in the population from Gujarat, West India.

METHODS

A total of 97 malignant oral carcinoma tissues and 52 cervical carcinoma tissues were analyzed by type-specific PCR for the presence of HPV type 16 and 18 infections.

RESULTS

None of the oral cancer patients revealed the presence of HPV type 16 and 18 infection. In cervical cancer, 31 (59.6%) patients were infected with HPV 16 and 18. Of these 31 HPV-positive cervical cancer patients, 28 (90.3%) were infected with HPV 16 and 3 (9.7%) were infected with HPV 18.

CONCLUSION

The results suggested that HPV 16 and 18 do not play an important role in oral carcinogenesis in the population from Gujarat, West India. However, HPV 16 is highly prevalent in the cervical cancer patients, which may be considered for planning of prevention programs such as screening and vaccination in women from this region.

Cyclin B1 overexpression in conventional oral squamous cell carcinoma and verrucous carcinoma- A correlation with clinicopathological features

Background: Nuclear localization of cyclin B1 is an indicator for cells undergoing mitotic division, and the overexpression has shown promising results as a good prognostic predictor for patients of squamous cell carcinoma (SCC). Cyclin B1 overexpression among histological grades of conventional oral squamous cell carcinoma (COSCC), as well as comparison with verrucous carcinoma (VC) has been less investigated. Study Design: Immunohistochemical expression of cyclin B1 was compared with various clinicopathological features in 30 primary COSCC and 31 primary VC cases. Result: Cyclin B1 showed significant overexpression for some clinical features for both the variants of oral squamous cell carcinoma. In histopathological variants, statistical significance was observed among grades of COSCC, as well as COSCC and its grades with VC. The concomitant increase in cyclin B1 overexpression from VC to grades COSCC was observed. Conclusion: Our study findings draw attention to cyclin B1 overexpression is involved in early carcinogenesis, cell differentiation and tumor proliferation.

Key words:Cyclin B1, oral squamous cell carcinoma, verrucous carcinoma, head and neck cancer.

Comprehensive analysis of human papillomavirus prevalence and the potential role of low-risk types in verrucous carcinoma

The role of human papillomavirus (HPV) infections in the development of verrucous carcinoma, a well-differentiated variant of squamous cell carcinoma with difficult differential diagnosis, is controversial in the literature. In this study, we analysed verrucous carcinoma from different origins for the presence and activity of a broad spectrum of HPV types, and carefully reviewed the histopathological features. A random series of 27 formalin-fixed, paraffin-embedded specimens of verrucous carcinoma was taken, representing the head and neck region (n=6), anogenital area (n=16) and extragenital skin region (n=5). After review of the histological slides, all samples were subjected to different polymerase chain reaction-based HPV detection techniques, together detecting a total of 83 HPV types, including both mucosal and cutaneous types. Histological revision was carefully performed. Lesions with keratinised papillae, blunt stromal invaginations and minimal cytological atypia were considered verrucous carcinoma. Condylomatous lesions with viral changes were defined as giant condyloma. Verrucous lesions that did not meet those criteria were classified as verrucous hyperplasia. Tumours with stromal infiltration were considered as invasive squamous cell carcinoma. Histological revision revealed that 13 out of 27 cases were verrucous carcinoma (one showing a double infection with HPV 35 and 45), 5 invasive squamous cell carcinomas, 5 verrucous hyperplasia (one with a double infection with HPV 4 and 8), 1 pseudoepitheliomatous hyperplasia and 3 giant condylomas. All three giant condylomas were low-risk HPV positive (HPV 6 and 11) and showed active mRNA transcription. None of the HPV-positive samples tested positive for diffuse p16(INK4A) staining. In conclusion, our results do not support a causal role of HPV in the development of verrucous carcinoma. Testing for LR-HPV, particularly HPV 6 and 11, may help in the differential diagnosis of lesions suspicious of verrucous carcinoma as those testing positive for LR-HPV most likely represent giant condylomas.

Promoter hypermethylation in primary squamous cell carcinoma of the oral cavity and oropharynx: a study of a Brazilian cohort

Epigenetic silencing of cancer-related genes plays an important role in oral/oropharyngeal squamous cell carcinoma (OSCC). We evaluated promoter hypermethylation of 4 cancer-related genes in OSCCs of a Brazilian cohort and determined its relationship with exposure to alcohol, tobacco, HPV infection and clinicopathological parameters. CDKN2A (cyclin-dependent kinase inhibitor 2A or p16), SFN (stratifin or 14-3-3 σ), EDNRB (endothelin receptor B) and RUNX3 (runt-related transcript factor-3) had their methylation patterns evaluated by MSP analysis in OSCC tumors (n = 45). HPV detection was carried out by PCR/RFLP. Aberrant methylation was detected in 44/45 (97.8 %) OSCC; 24.4 % at CDKN2A, 77.8 % at EDNRB, 17.8 % at RUNX3 and 97.8 % at SFN gene. There was no significant association between methylation patterns and clinical parameters. HPV (subtype 16) was detected in 3 out of 45 patients (6 %). Our findings indicate that HPV infection is uncommon and methylation is frequent in Brazilian OSCCs, however, EDNRB and SFN gene methylation are not suitable OSCC biomarkers due to indistinct methylation in tumoral and normal samples. In contrast, CDKN2A and RUNX3 genes could be considered differentially methylated genes and potential tumor markers in OSCCs.