p16 Immunohistochemistry Can Be Used to Detect Human Papillomavirus in Oral Cavity Squamous Cell Carcinoma

MRI for Differentiation between HPV-Positive and HPV-Negative Oropharyngeal Squamous Cell Carcinoma: A Systematic Review

Human papillomavirus (HPV) is an important risk factor for oropharyngeal squamous cell carcinoma (OPSCC). HPV-positive (HPV+) cases are associated with a different pathophysiology, microstructure, and prognosis compared to HPV-negative (HPV-) cases. This review aimed to investigate the potential of magnetic resonance imaging (MRI) to discriminate between HPV+ and HPV- tumours and predict HPV status in OPSCC patients. A systematic literature search was performed on 15 December 2022 on EMBASE, MEDLINE ALL, Web of Science, and Cochrane according to PRISMA guidelines. Twenty-eight studies (n = 2634 patients) were included. Five, nineteen, and seven studies investigated structural MRI (e.g., T1, T2-weighted), diffusion-weighted MRI, and other sequences, respectively. Three out of four studies found that HPV+ tumours were significantly smaller in size, and their lymph node metastases were more cystic in structure than HPV- ones. Eleven out of thirteen studies found that the mean apparent diffusion coefficient was significantly higher in HPV- than HPV+ primary tumours. Other sequences need further investigation. Fourteen studies used MRI to predict HPV status using clinical, radiological, and radiomics features. The reported areas under the curve (AUC) values ranged between 0.697 and 0.944. MRI can potentially be used to find differences between HPV+ and HPV- OPSCC patients and predict HPV status with reasonable accuracy. Larger studies with external model validation using independent datasets are needed before clinical implementation.

Prevalence of high-risk human papillomavirus in oral squamous cell carcinoma with or without chewing habits

Oral cancer (OC) is the most common cancer in Pakistani males and the second most common in females. Major risk factors include peculiar chewing habits, human papillomavirus (HPV) infection and molecular pathways. However, less data is available for this avertible cancer regarding its association with high-risk HPV (HR-HPV) and chewing habits in this region. Therefore, this study was done to determine the prevalence of HR-HPV in oral squamous cell carcinoma (OSCC) and its correlation with p16 and chewing habits. Formalin-fixed paraffin-embedded (FFPE) biopsy specimens of 186 samples were tested for HR-HPV type 16/18 by PCR, followed by p16 immunostaining (IHC) in a subset of cases (n = 50). Appropriate statistical tests were applied to find the association between HR-HPV/p16 and peculiar chewing habits with significance criteria of p<0.05 with 95% CI. HR-HPV (type 16 &18) was present in seven out of 186 cases (3.8%). Of these seven cases, five were positive for HPV16, whereas two were positive for HPV16/18. The overall expression of p16 protein in 50 samples was 38% (n = 19), and among these 19-IHC positive samples, 26% were positive for HR-HPV DNA. No significant association was found between HR-HPV positivity and p16 and chewing habits (p>0.05). It was concluded that HR-HPV prevalence in OSCC was very low in our population, with no statistically significant correlation with p16 and chewing habits. These results suggest the role of HR-HPV as an independent risk factor in OSCC in the local setting.

Treatment outcomes of standard (high dose) cisplatin and non-standard chemotherapy for locally advanced head and neck cancer

INTRODUCTION

Concurrent chemoradiotherapy with high-dose (HD) cisplatin is the standard treatment for locally advanced head and neck squamous cell carcinoma (LA-HNSCC). Due to the higher treatment-related adverse effects with standard therapy, alternative regimens (non-standard therapy), namely, lower dose weekly cisplatin, carboplatin/paclitaxel, or cetuximab are considered. There is, however, no consensus on non-standard regimens. We aimed to investigate the efficacy and safety profile of these regimens.

METHODS

This single centre retrospective cohort study included all consecutive adult patients with newly diagnosed LA-HNSCC treated with either standard or non-standard regimens between January 2016 and April 2021. The primary outcome was 2-year failure-free survival (FFS). The secondary outcomes included acute toxicities, hospitalisation rates, dose modifications, treatment failure rates (TFR), and overall survival.

RESULTS

About 235 patients were included in the final analysis; median age was 61 years (IQR 55-67), and 87% were male. Most had oropharyngeal tumours (85.5%) and p16-positivity was frequent (80%). About 56% received non-standard regimens: weekly cisplatin = 79 and non-cisplatin = 48. These patients had higher Charlson Comorbidity Index (CCI; p < .001) and lower European Cooperative Oncology Group (ECOG)-0 (p = .003). There was no difference in 2-year FFS (hazard ratio [HR] = 1.16; 95% confidence interval - [CI] 0.65-2.05), hospitalisation and grade-3 toxicity rates between the two regimens. Nausea and vomiting were lower in the non-standard regimen (3.0% vs. 16%, p < .001). Dose reductions, adjusted for age, sex, and CCI, were less likely in the non-standard regimen (OR = 2.36; 95%-CI: 1.01-5.49, p = .007).

CONCLUSIONS

We demonstrated similar efficacy of lower dose weekly cisplatin and carboplatin/paclitaxel regimens and better safety profile of weekly cisplatin compared to standard HD cisplatin regimens for LA-HNSCC. Multicenter randomised control trials are required in HD cisplatin-ineligible patients.

The effect of HPV DNA and p16 status on the prognosis of patients with hypopharyngeal carcinoma: a meta-analysis

OBJECTIVE

To evaluate whether the presence of human papillomavirus (HPV) DNA and p16 might be associated with better prognosis in patients with hypopharyngeal carcinoma (HPC), especially on overall survival (OS) and disease-free survival (DFS).

METHOD

PubMed, the Cochrane Library, the Web of Science and EMBASE were searched from inception to April 2021 to search for HPV DNA- and p16-related prognostic articles on HPC. Meta-analysis was performed on the selected articles according to the inclusion and exclusion criteria. Publication bias was assessed for the included studies with Egger's test. All studies were analyzed by using Stata 16.0 statistical software.

RESULTS

A total of 18 studies were included, including 12 HPV DNA studies and 11 p16 studies. Meta-analysis showed that HPV DNA positivity was a strong prognostic factor for improved OS in patients with HPC, with a pooled hazard ratio (HR) of 0.61 (95% CI, 0.54-0.69), but there was no statistically significant difference in DFS (HR, 0.60; 95% CI, 0.31-1.16). Patients with p16-positive tumors had better OS (HR, 0.66; 95% CI, 0.49-0.89) and DFS (HR, 0.59; 95% CI, 0.44-0.78) than patients with p16-negative tumors.

CONCLUSIONS

This study suggests that the presence of HPV DNA leads to better OS in patients with HPC, and the presence of p16 also corresponds to better OS and DFS. Our results provide up-to-date evidence to clinicians and researchers. Larger studies adjusting for prognostic factors are needed in subsequent studies.

[Clinicopathological study in 28 cases of oral basaloid squamous cell carcinomas]

OBJECTIVE

To investigate the clinicopathologic features and prognostic factors in oral basaloid squamous cell carcinoma.

METHODS

Retrospective analysis of oral basaloid squamous cell carcinomas patients who underwent tumor resection during the period from January 2002 to December 2020 in the authors' hospital, especially the clinicopathologic characteristics of 28 cases with confirmed diagnosis and follow-up data. Immunohistochemistry was performed to define the helpful markers for differentiation diagnosis. The factors influencing the prognosis were evaluated based on Kaplan-Meier method.

RESULTS

The tongue and mouth floor (11 cases, 39.3%) were the most frequently involved sites, followed by gingiva (6 cases, 21.4%), buccal (5 cases, 17.9%), palate (4 cases, 14.3%), and oropharynx (2 cases, 7.1%). The majority of basaloid squamous cell carcinomas were in advanced stage, with 12 cases in stage Ⅱ and 16 cases in stages Ⅲ-Ⅳ. Twelve of 28 patients were identified to have cervical lymph node metastasis, which was confirmed by histopathological examination. The incidence rate of lymph node metastasis was 42.9% (12/28). Nine tumors recurred, with one metastasized to the lung. At the meantime, the 28 conventional squamous cell carcinomas were matched with the same stage, among which 13 cases were identified with cervical lymph node metastasis. The incidence rate of lymph node metastasis was 46.4% (13/28). Five cases recurred, with two cases that metastasized to the lung and one to the brain. The 5-year overall survival rates of the basaloid squamous cell carcinoma and conventional squamous cell carcinoma patients were 54.6% and 53.8%, respectively. Histopathologically, basaloid cells consisted of tumor islands without evident keratinization but frequently with comedo-like necrosis within the tumor islands. CK5/6 and P63 exhibited strongly positive in all the 28 cases, whereas neuroendocrine markers, CgA and Syn, were negative. Eight cases positively expressed P16; one case showed focal SOX10 positive but CK7 negative.

CONCLUSION

The majority of oral basaloid squamous cell carcinomas present in advanced stage with a high tendency to lymph node metastasis, but the overall survival rates are not significantly different from conventional squamous cell carcinomas matched with the same stage. The human papilloma virus (HPV), as HPV-positivity rate is high, correlates to good prognosis. In addition, CK7 & SOX10 immunohistochemistry could contribute to differential diagnosis for basaloid squamous cell carcinoma with solid adenoid cystic carcinoma.

Radical excision of inguinal condyloma acuminatum following 51 years of untreated growth, found to be squamous cell carcinoma

Giant condyloma acuminatum, caused by herpes simplex virus infection, is a large cauliflower shaped lesion that has a propensity to infiltrate surrounding tissues with paradoxically benign microscopic/histological appearance. This lesion is often benign, though it does have the potential for malignant transformation. Here we present a case that demonstrates this potential and describes the pathological and histological findings in detail. The report concludes with the clinical reasoning for considering surgical resection in these patients.

Low Frequency of Human Papillomavirus in Strictly Site-Coded Oral Squamous Cell Carcinomas, Using the Latest NHI/SEER-ICD Systems: A Pilot Observational Study and Critical Review

Simple Summary

The incidence of oropharyngeal squamous cell carcinomas (OPSCCs) has increased in the last decades, and this seems to be correlated to the infectious epidemiological trend of human papillomavirus (HPV). The prevalence of HPV-positive OPSCCs is approximately 70%, with involvement mainly of the tonsillar area. On the role of HPV in oral squamous cell carcinoma (OSCC), very few studies have investigated the prevalence of HPV in strictly site-codified OSCC, excluding the base of the tongue as distinct oropharyngeal entity. As a result, an inappropriate estimation of HPV infection in OSCC has been observed. We investigated HPV status, using a combination of detection methods, in a sample of 40 subjects with OSCC coded by the latest site classifications. Moreover, we performed a critical review of the studies with the same outcomes. The main finding of our investigation was a low frequency of HPV-positive OSCC, suggesting no significant HPV role in strictly oral carcinogenesis.

Abstract

The aim of this study was to evaluate HPV status in oral squamous cell carcinoma (OSCC), as coded by the latest classifications and applying a combination of detection methods used in clinical practice. Forty-two patients with suspect OSCC were consecutively recruited. Patients underwent an incisional biopsy for histological OSCC diagnosis and HPV identification by PCR DNA and p16 IHC. All lesions were coded by the latest ICD-0-3.2 site/histology classifications, as proposed for OSCC by the National Cancer Institute Surveillance, Epidemiology and End Results Programs. Moreover, a comparative analysis review, critically evaluated by the same site-coded systems and HPV detection methods, was performed. In 40 confirmed cases of OSCC, the frequency of HPV infection was 10% (4/40). Among positive patients, two cases were PCR DNA/p16 IHC positive (high-risk HPV 51, high-risk HPV 67), two cases were PCR DNA positive/p16 IHC negative (high-risk HPV 31 + 68, high-risk HPV 66). Applying the latest site coding systems for OSCC, the frequency of HPV infection in this study and in similar, reviewed investigations was low (from 3.3% to 12.5%). These results suggested no significant HPV role in oral carcinogenesis, particularly where an updated site-coded classification of OSCCs (categorically excluding the base of the tongue) had been performed.

Detection of human papillomavirus in oropharyngeal squamous cell carcinoma

Worldwide there has been a significant increase in the incidence of oropharyngeal squamous cell carcinoma (OPSCC) etiologically attributed to oncogenic human papillomavirus (HPV). Reliable and accurate identification and detection tools are important as the incidence of HPV-related cancer is on the rise. Several HPV detection methods for OPSCC have been developed and each has its own advantages and disadvantages in regard to sensitivity, specificity, and technical difficulty. This review summarizes our current knowledge of molecular methods for detecting HPV in OPSCC, including HPV DNA/RNA polymerase chain reaction (PCR), loop-mediated isothermal amplification (LAMP), p16 immunohistochemistry (IHC), and DNA/RNA in situ hybridization (ISH) assays. This summary may facilitate the selection of a suitable method for detecting HPV infection, and therefore may help in the early diagnosis of HPV-related carcinoma to reduce its mortality, incidence, and morbidity.

The frequency of high-risk human papillomavirus types, HPV16 lineages, and their relationship with p16INK4a and NF-κB expression in head and neck squamous cell carcinomas in Southwestern Iran

High-risk human papillomaviruses (hr-HPVs) are the key risk factors implicated in the development of a significant proportion of head and neck squamous cell carcinomas (HNSCCs). We aimed to investigate the distribution of hr-HPV types and HPV16 lineages in a sample of patients with HNSCC and the possible association between HPV status and the expression of P16INK4A and NF-κB in Iranian HNSCC patients. We examined 108 formalin-fixed, paraffin-embedded (FFPE) histologically confirmed primary SCC tissue specimens of different head and neck anatomical sites. HPV types and HPV16 lineages were determined by nested PCR and overlapping nested PCR assays, respectively, followed by gene sequencing and phylogenetic analysis. The expression of p16INK4a and NF-κB was evaluated by immunohistochemistry. Twenty-five (23.1%) HNSCC tissue specimens were tested positive for HPV infection. The most prevalent HPV type was HPV-16, followed by HPV18 and HPV11. HPV16 variants belonged to the lineage A and lineage D which were further sorted into sublineages A1, A2, and D2. A significant association between HPV status and p16INK4a immunoreactivity was observed in more than 76% of the HPV-related HNSCCs (P < 0.0001). The overexpression of p16INK4a and cytoplasmic NF-κB was more common in low-grade HNSCC tumors. Our data highlights that HPV16, in particular the A2 sublineage, followed by A1 and D2 sublineages are the major agents associated with HNSCCs in Iran. Based on HPV16 predominance and its lineage distribution pattern, it seems that the prophylactic vaccines developed for cervical cancer prevention could also be applicable for the prevention of HPV-related HNSCCs in our population.

The utility of high-risk human papillomavirus E6/E7 mRNA in situ hybridization in assessing HPV status on cell block

INTRODUCTION

Assessment of human papillomavirus (HPV) status is critical to the treatment and prognosis of patients with oropharyngeal squamous cell carcinoma. Patients often present with enlarged cervical lymph nodes which are amenable to fine needle aspiration (FNA) and cell block creation. The most widely used method for assessing HPV status is the surrogate marker p16. Other HPV specific methods such as high-risk HPV E6/E7 mRNA in situ hybridization (ISH) have been shown to perform as well as p16 and are easier to interpret. Our study evaluates the utility of high-risk HPV mRNA ISH in cell block specimens.

METHODS

Thirty-six cases of metastatic squamous cell carcinoma in cervical neck lymph node FNAs were identified over a 3-year period. All cases had p16 immunohistochemistry (IHC) performed on cell block. HR HPV mRNA ISH was performed on the cell block and compared to the p16 results. Additionally, p16 and HR HPV mRNA ISH status was assessed in those cases with corresponding surgical resections.

RESULTS

HR HPV mRNA ISH confirmed the p16 IHC (either positive or negative) in 24 of the 36 cases (66.7%). Six false negative cases were p16 negative/HR HPV mRNA ISH positive. HR HPV mRNA ISH was positive in 75% of the four p16 equivocal cases. Two cases were p16 positive/HR HPV mRNA ISH negative.

CONCLUSIONS

HR HPV mRNA ISH is no more difficult to perform in the IHC lab and is easier to interpret than p16 IHC. HR HPV mRNA ISH is a useful alternative to p16 in cell block specimens.

p16 Immunohistochemical Expression in Head and Neck Squamous Cell Carcinoma: Association With Prognostic Parameters

Background p16 is a tumor suppressor gene, over expression of which is considered as a surrogate marker of oncogenic human papillomavirus (HPV) infection. Moreover, p16 over expression correlates with good prognosis in head and neck squamous cell carcinoma (HNSCC). In the present study, we aimed to evaluate the frequency of p16 overexpression in HNSCC in our setup and its association with clinicopathologic parameters. Methods We performed p16 immunohistochemistry (IHC) on 144 cases of HNSCC. Association of p16 overexpression with various clinicopathologic parameters including T-stage, N-stage, grade, recurrence status, and risk factors was evaluated. Results p16 over expression was noted in 22.9% (33 cases), while 21.5% (31 cases) were focal positive and 55.6% (80 cases) were negative for p16 over expression. On the basis of percentage of expression; > 70% p16 expression was noted in 4.9% (7 cases), 9% (13 cases) showed 51% - 70% p16 expression, 9% (13 cases) revealed 11%-50% p16 expression, while 77.1% cases revealed no expression or < 10% p16 expression. Significant association of p16 expression was noted with nodal metastasis and extranodal spread while no significant association of p16 was noted with other prognostic parameters and risk factors. Conclusion Our data revealed that high expression (> 50%) of p16 is low in oropharyngeal squamous cell carcinoma in our setup. These finding suggest a low prevalence of HPV as a cause of HNSCC in our population. Moreover, p16 expression was found to be associated with some good prognostic parameters like lack of nodal metastasis, however, no significant association was noted with overall disease-free survival.

Assessment of TLR4 and TLR9 signaling and correlation with human papillomavirus status and histopathologic parameters in oral tongue squamous cell carcinoma

OBJECTIVES

Toll-like receptors (TLRs) may promote or inhibit tumor progression. The aim of this study was to assess the expression of TLR4 and TLR9 and their downstream targets in oral tongue squamous cell carcinoma (OTSCC) in correlation with histopathologic parameters and human papillomavirus (HPV) status.

STUDY DESIGN

OTSCC (fully or superficially invasive and in situ) were studied. Immunohistochemical expression of TLR4, TLR9, nuclear factor-κΒ (NF-κΒ/p65), and interferon-β (IFN-β) was evaluated in tumor and inflammatory cells and in adjacent morphologically normal mucosa. HPV status was also determined.

RESULTS

TLR4 showed increased expression levels in tumor and infiltrating inflammatory cells compared with adjacent mucosa, especially in fully invasive cases; a negative correlation between TLR4 levels in inflammatory cells and tumor grade was observed. TLR9 was upregulated in tumor and infiltrating inflammatory cells compared with the adjacent mucosa; its expression in inflammatory cells was higher in well differentiated tumors. NF-κΒ and IFN-β were elevated in cancerous tissues, especially in fully invasive cases, and positively correlated with TLR4 and/or TLR9. HPV positivity (detected in 15.9% of the cases) demonstrated positive correlation with TLR9 and NF-κΒ levels.

CONCLUSIONS

TLR4 and TLR9 are upregulated in OTSCC and its microenvironment and, by affecting important downstream molecules, such as NF-κB and IFN-β, may play a role in oral cancer development and progression.

Prevalence and incidence of oral cancer in low- and middle-income countries: A scoping review

INTRODUCTION

Oral cancer is common cancer in many low- and middle-income countries (LMICs) with a low five-year survival rate. It is among the four most common types of cancer in South East Asia region. In South-Central Asia, lip and oral cavity cancer is the second most common cancer according to the specific cancer types.

METHODS

This scoping review intended to investigate published studies on the current prevalence and incidence of oral cancer in LMICs. The review was conducted applying the search words "Oral Cancer" and "Mouth neoplasm" as the Medical Subject Heading (MeSH) major topic and "Epidemiology" and ("prevalence" OR "incidence") as the MeSH subheading; the search was supplemented by cross-references. Included studies met the following criteria: original studies, reporting of prevalence or incidence rates, population-based studies, studies in English language and studies involving humans.

RESULTS

The sample sizes ranged from 486 to 101,761 with 213,572 persons included. Buccal mucosa is one of the most common sites of oral cancer, associated with the widespread exposure to chewing tobacco. The incidence is likely to rise in the region where gutkha, pan masala, pan-tobacco and various other forms of chewing tobacco are popular.

CONCLUSION

This review contributes to useful information on prevalence and incidence estimates of oral cancer in LMICs.

p16INK4a as a proliferation marker unrelated to HPV expression in odontogenic cysts and tumors

INTRODUCTION

p16INK4a is a tumor suppressor protein that retards cell cycle progression from G1 to S phase. Prior studies have evaluated p16INK4a expression in odontogenic keratocyst and ameloblastoma, but data regarding other odontogenic cysts and tumors have been sparse.

METHODS

With IRB approval, cases from the following entities were identified from archives of the UF Oral Pathology Biopsy Service (2005-2015): benign incidental odontogenic rest, dentigerous cyst, lateral periodontal cyst, calcifying odontogenic cyst, glandular odontogenic cyst, odontogenic keratocyst, orthokeratinized odontogenic cyst, adenomatoid odontogenic tumor, calcifying epithelial odontogenic tumor, and ameloblastoma. All cases were submitted for p16INK4a immunohistochemical testing.

RESULTS

Results were scored as follows: nuclear and cytoplasmic staining of <5% cells (score 0), 5%-25% (score 1), 25%-50% (score 2), >50% (score 3). No significant difference in p16INK4a staining was noted between odontogenic cysts and the listed odontogenic tumors (chi-square, P = .540). When comparing lesions with higher recurrence rates (over 25% as reported in the literature) versus lesions with low recurrence rates (under 25%), higher recurrence correlated to significantly higher p16INK4a positivity (chi-square, P = .001). Follow-up testing was performed on 18 cases with "2" or "3" p16INK4a expression scores for high-risk HPV strains through HPV in situ hybridization (ISH) messenger RNA testing with no cases exhibiting a positive result.

CONCLUSION

This study exhibits an association between increased p16INK4a positivity and odontogenic lesions with higher recurrence rates and highlights the role of p16INK4a as a progression marker unrelated to HPV expression in this group of pathologic entities.

Human Papillomavirus Infection, p16INK4a Expression and Genetic Alterations in Vietnamese Cervical Neuroendocrine Cancer

Neuroendocrine cervical cancer is a rare subtype of cervical cancer with a highly aggressive malignancy. This study was conducted to analyse the human papillomavirus (HPV) infection and molecular abnormalities in Vietnamese neuroendocrine carcinomas of the uterine cervix. HPV genotyping and p53 mutations were examined using polymerase chain reaction (PCR)-based direct sequencing. Mutations of epidermal growth factor receptor (EGFR), Kirsten rat sarcoma (KRAS), neuroblastoma RAS viral oncogene homolog (NRAS) and v-Raf murine sarcoma viral oncogene homolog B (BRAF) were identified using commercial kits. Four high-risk HPV genotypes were identified in 26 (86.7%) out of a total of 30 tumours. The prevalence of HPV 16, 18, 31 and 45 was 20.0%, 50.0%, 20.0% and 36.7%, respectively. Overexpression of p16^INK4a was observed in 93.3% of cases and was significantly correlated with high-risk HPV infections. Furthermore, p53 and NRAS mutations were detected in five (16.7%) and one (3.3%) cases, respectively, whereas no EGFR, KRAS or BRAF mutations were observed. These results demonstrate that high-risk HPV infection may be an important oncogenic factor for the development and progression of cervical neuroendocrine carcinoma.

The Prognostic Roles of Pretreatment Circulating Tumor Cells, Circulating Cancer Stem-Like Cells, and Programmed Cell Death-1 Expression on Peripheral Lymphocytes in Patients with Initially Unresectable, Recurrent or Metastatic Head and Neck Cancer: An Exploratory Study of Three Biomarkers in One-time Blood Drawing

Circulating tumor cells (CTCs) and immune status are strongly related to cancer prognosis, although few studies have examined both factors. This prospective observational study (ClinicalTrials.gov: NCT02420600) evaluated whether CTCs, circulating cancer stem-like cells (cCSCs), and peripheral lymphocytes with/without Programmed cell death protein 1 (PD-1) expression were associated with prognosis among patients receiving palliative chemotherapy for initially unresectable, recurrent/metastatic head and neck squamous cell carcinoma (rmHNSCC). Thirty-four patients were enrolled between January 2015 and June 2016. Overall survival (OS) was associated with a higher CTC number (hazard ratio [HR]: 1.01, p = 0.0004) and cCSC ratio (HR: 29.903, p < 0.0001). Progression-free survival (PFS) was also associated with CTC number (HR: 1.013, p = 0.002) and cCSC ratio (HR: 10.92, p = 0.003). A CD8⁺ proportion of ≥ 17% was associated with improved OS (HR: 0.242, p = 0.004). A CD4: CD8 ratio of >1.2 was associated with poorer trend of PFS (HR: 2.12, p = 0.064). PD-1 expression was not associated with survival outcomes. Baseline CTCs, cCSC ratio, and CD8⁺ ratio may predict prognosis in rmHNSCC.

Examining the contribution of smoking and HPV towards the etiology of oral cavity squamous cell carcinoma using high-throughput sequencing: A prospective observational study

Oral cavity Squamous Cell Carcinoma (OCSCC) is a common form of head and neck cancer throughout the developed and developing world. However, the etiology of OCSCC is still unclear.

Here, we explored the extent to which tobacco use, Human Papillomavirus (HPV) infection and genetic and transcriptomic changes contributed to the oncogenesis of OCSCC. In a prospective observational study, we analysed fresh tissue biopsies from 45 OCSCC collected from 51 subjects presenting with OCSCC to the Brisbane Head and Neck Clinics between 2013 and 2015. Exploration of the genetic and transcriptomic landscape of the biopsies were performed using RNA sequencing (RNA-seq) and whole exome sequencing. HPV associated tumours were determined using p16 staining of histological sections and RNA sequencing. Patient demographics including tumor location within the oral cavity, and history of tobacco and alcohol use were correlated with genomic and transcriptomics analyses. About 4.5% of OCSCC were HPV associated. The most frequent mutations in the OCSCC samples were in the TP53 and CDKN2A genes, but no association of specific mutations with HPV or tobacco use was observed. Using weighted gene co-expression network analysis to explore the RNA-seq data, tumors from participants with a history of tobacco use showed a significant trend towards increased mammalian target of Rapamycin (mTOR) signaling and decreased mitochondrial respiration. In conclusion, HPV was shown to be an uncommon association with OCSCC and changes in TP53 transcriptional regulation, mTOR signaling and mitochondrial function were associated with a history of tobacco use. Larger data sets will be required to enable detection of differences which may help with development of personalized therapeutics in the future.

Smoking-induced control of miR-133a-3p alters the expression of EGFR and HuR in HPV-infected oropharyngeal cancer

Purpose

Human papillomavirus (HPV) infected oropharyngeal squamous cell carcinoma (OPSCC) patients have a better prognosis compared to HPV(-) counterparts. However, a subset of HPV(+) patients with a smoking history fail to respond to the standard of care treatments such as radiation and chemotherapy. To understand the underlying mechanism driving HPV(+) OPSCC patient resistance to treatment and recurrence, we sought to identify and characterize the differentially expressed miRNAs and their target genes in HPV(+) smokers and non-smokers.

Experimental design

MicroRNA expression analysis was performed using Nanostring in tumor tissues isolated from a prospective cohort of HPV(+) smoking (n = 9) and HPV(+) (n = 13) non-smoking OPSCC patients. Identified miRNAs of interest were further validated using qRT-PCR in cigarette smoke extract (CSE) treated HPV(+) and E6/E7 overexpressing HPV(-) cells.

Results

In comparison to OPSCC HPV(+) non-smokers, 38 miRNAs were significantly altered in the HPV(+) smoker patients cohort and out of that 9 were downregulated. Altered miRNA expression was also detected in the serum and metastatic lymph nodes of HPV(+) smokers versus non-smokers. Expression of miR-133a-3p was significantly downregulated in OPSCC smokers, HPV(+) cells and E6/E7 overexpressing HPV(-) cells treated with CSE. Reduction of miR-133a-3p induced the upregulation of miR-133a-3p target mRNAs EGFR and HuR.

Conclusions

Our results indicate that miR-133a-3p is a target of smoking-induced changes in HPV(+) patients and alters the expression of EGFR and HuR which may promote HPV associated oropharyngeal cancer. Therefore, future treatment strategies for HPV(+) OPSCC smokers should focus on EGFR inhibition and the development of selective therapies to target HuR.

Human Papillomavirus Testing in Head and Neck Carcinomas: Guideline From the College of American Pathologists

Context Human papillomavirus (HPV) is a major cause of oropharyngeal squamous cell carcinomas, and HPV (and/or surrogate marker p16) status has emerged as a prognostic marker that significantly impacts clinical management. There is no current consensus on when to test oropharyngeal squamous cell carcinomas for HPV/p16 or on which tests to choose. Objective To develop evidence-based recommendations for the testing, application, interpretation, and reporting of HPV and surrogate marker tests in head and neck carcinomas. Design The College of American Pathologists convened a panel of experts in head and neck and molecular pathology, as well as surgical, medical, and radiation oncology, to develop recommendations. A systematic review of the literature was conducted to address 6 key questions. Final recommendations were derived from strength of evidence, open comment period feedback, and expert panel consensus. Results The major recommendations include (1) testing newly diagnosed oropharyngeal squamous cell carcinoma patients for high-risk HPV, either from the primary tumor or from cervical nodal metastases, using p16 immunohistochemistry with a 70% nuclear and cytoplasmic staining cutoff, and (2) not routinely testing nonsquamous oropharyngeal carcinomas or nonoropharyngeal carcinomas for HPV. Pathologists are to report tumors as HPV positive or p16 positive. Guidelines are provided for testing cytologic samples and handling of locoregional and distant recurrence specimens. Conclusions Based on the systematic review and on expert panel consensus, high-risk HPV testing is recommended for all new oropharyngeal squamous cell carcinoma patients, but not routinely recommended for other head and neck carcinomas.

Clinically actionable mutation profiles in patients with cancer identified by whole-genome sequencing

Next-generation sequencing (NGS) efforts have established catalogs of mutations relevant to cancer development. However, the clinical utility of this information remains largely unexplored. Here, we present the results of the first eight patients recruited into a clinical whole-genome sequencing (WGS) program in the United Kingdom. We performed PCR-free WGS of fresh frozen tumors and germline DNA at 75× and 30×, respectively, using the HiSeq2500 HTv4. Subtracted tumor VCFs and paired germlines were subjected to comprehensive analysis of coding and noncoding regions, integration of germline with somatically acquired variants, and global mutation signatures and pathway analyses. Results were classified into tiers and presented to a multidisciplinary tumor board. WGS results helped to clarify an uncertain histopathological diagnosis in one case, led to informed or supported prognosis in two cases, leading to de-escalation of therapy in one, and indicated potential treatments in all eight. Overall 26 different tier 1 potentially clinically actionable findings were identified using WGS compared with six SNVs/indels using routine targeted NGS. These initial results demonstrate the potential of WGS to inform future diagnosis, prognosis, and treatment choice in cancer and justify the systematic evaluation of the clinical utility of WGS in larger cohorts of patients with cancer.

LIM-Only Protein 4 (LMO4) and LIM Domain Binding Protein 1 (LDB1) Promote Growth and Metastasis of Human Head and Neck Cancer (LMO4 and LDB1 in Head and Neck Cancer)

Squamous cell carcinoma of the head and neck (HNSCC) accounts for more than 300,000 deaths worldwide per year as a consequence of tumor cell invasion of adjacent structures or metastasis. LIM-only protein 4 (LMO4) and LIM-domain binding protein 1 (LDB1), two directly interacting transcriptional adaptors that have important roles in normal epithelial cell differentiation, have been associated with increased metastasis, decreased differentiation, and shortened survival in carcinoma of the breast. Here, we implicate two LDB1-binding proteins, single-stranded binding protein 2 (SSBP2) and 3 (SSBP3), in controlling LMO4 and LDB1 protein abundance in HNSCC and in regulating specific tumor cell functions in this disease. First, we found that the relative abundance of LMO4, LDB1, and the two SSBPs correlated very significantly in a panel of human HNSCC cell lines. Second, expression of these proteins in tumor primaries and lymph nodes involved by metastasis were concordant in 3 of 3 sets of tissue. Third, using a Matrigel invasion and organotypic reconstruct assay, CRISPR/Cas9-mediated deletion of LDB1 in the VU-SCC-1729 cell line, which is highly invasive of basement membrane and cellular monolayers, reduced tumor cell invasiveness and migration, as well as proliferation on tissue culture plastic. Finally, inactivation of the LDB1 gene in these cells decreased growth and vascularization of xenografted human tumor cells in vivo. These data show that LMO4, LDB1, and SSBP2 and/or SSBP3 regulate metastasis, proliferation, and angiogenesis in HNSCC and provide the first evidence that SSBPs control LMO4 and LDB1 protein abundance in a cancer context.

Human Papilloma Virus in Oral Cavity Cancer and Relation to Change in Quality of Life Following Treatment-a Pilot Study from Northern India

Human papilloma virus (HPV)-associated head and neck cancer (HNC) has generated significant amount of research interest in recent times with focus shifted to oral cavity squamous cell cancer (OCSCC) after oropharyngeal cancer. Due to high incidence of OCSCC and anecdotal reports on association of HPV infection from northern region of India, this study was conceived to investigate HPV infection and establish its association with lifestyle habits such as tobacco, alcohol consumption, oro-genital sex, number of sexual contacts, and change in quality of life posttreatment. A total of 43 primary OCSCC biopsy specimens were collected. These samples were analyzed for HPV DNA genotyping which was done by using 13 high-risk HPV real-time PCR kits. Quality of life was assessed using University of Washington questionnaire for HNC patients, which was administered pretreatment and 3-months posttreatment. HPV presence was confirmed in only three patients (7.0 %). HPV positivity did not find any statistical correlation with age, gender, residence, addiction habit, stage, tumor size, nodal status, tumor grade, and number of sexual contacts. There was no significant (p > 0.05) difference in the average percent change in QOL parameters from pretreatment to posttreatment when correlated with HPV status.

Histopathological analysis of oral squamous cell carcinoma in nonsmokers and nondrinkers

A distinct clinical subgroup of nonsmoking (NS) and nondrinking (ND) patients with oral squamous cell carcinoma (OSCC) has been identified. The objective of the study was to assess this cohort for molecular variations in the disease process and if these could be attributed to clinical or epidemiological characteristics. One hundred and twenty-nine consecutive patients (71 males, 58 females) treated for OSCC were assessed at the Royal Melbourne Hospital between January 2007 and July 2010. Formalin-fixed paraffin embedded (FFPE) sections were stained for p53, p16, cyclin D1, and epidermal growth factor receptor (EGFR). Biomarker overexpression was observed in 72 (56%) cases for p53, 23 (18%) for p16, 45 (35%) for cyclin D1, and 72 (56%) for EGFR. Multiple logistic regression analysis revealed that tongue tumors ( p = 0.012) and late stage cancers ( p = 0.031) were more likely to have cyclin D1 overexpression. Further, older patients significantly more often had cyclin D1 overexpression ( p = 0.008) and NSND patients had more p16 expression ( p = 0.043). In contrast, smokers were more likely to have EGFR overexpression ( p = 0.033). Concurrent overexpression of p53 and cyclin D1 were observed ( p = 0.030). Smoking, site, and stage of OSCC can influence biomarker expression, with p16 overexpression specifically observed in NSND, indicating fundamental differences in the mechanisms of oral carcinogenesis among different patient cohorts.

HPV and cancer of the oral cavity

Increased awareness of human papillomavirus (HPV) as an etiological cause of head and neck squamous cell carcinoma has increased the interest in analysis of distinct oral sub-sites. It is currently under debate, whether HPV plays a role in the development of squamous cell carcinoma of the oral cavity (OSCC). The weakness in most published studies is the lack of performing different HPV detection tests combined with analysis for biological activity of the virus. In addition, different sub-sites of the oral cavity had been combined to a single entity, which retrospectively leads to a highly heterogeneous basis of data. In this review we mainly discuss the unclear role of HPV in OSCC development.

Recent Progress in Therapeutic Treatments and Screening Strategies for the Prevention and Treatment of HPV-Associated Head and Neck Cancer

The rise in human papillomavirus (HPV)-associated head and neck squamous cell carcinoma (HNSCC) has elicited significant interest in the role of high-risk HPV in tumorigenesis. Because patients with HPV-positive HNSCC have better prognoses than do their HPV-negative counterparts, current therapeutic strategies for HPV⁺ HNSCC are increasingly considered to be overly aggressive, highlighting a need for customized treatment guidelines for this cohort. Additional issues include the unmet need for a reliable screening strategy for HNSCC, as well as the ongoing assessment of the efficacy of prophylactic vaccines for the prevention of HPV infections in the head and neck regions. This review also outlines a number of emerging prospects for therapeutic vaccines, as well as for targeted, molecular-based therapies for HPV-associated head and neck cancers. Overall, the future for developing novel and effective therapeutic agents for HPV-associated head and neck tumors is promising; continued progress is critical in order to meet the challenges posed by the growing epidemic.

Bronchogenic cancer: It still exists

OBJECTIVES/HYPOTHESIS

Branchial cleft cysts rank among the most common differential diagnoses of cystic cervical masses. Rarely, classic cystic structures exhibit a squamous cell carcinoma differentiation that represents a bronchogenic carcinoma. The existence of bronchogenic carcinoma is controversial due to the lack of systematic immunohistologic workup. The present study aimed to identify the clinical and immunohistologic features of bronchogenic carcinoma to clearly distinguish this entity from other cystic cervical masses.

METHODS

Immunohistologic (epidermal growth factor receptor; cytokeratin 5, 6, 7, 13; and p16) and epidemiologic assessments were performed for branchial cleft cysts (n = 63), bronchogenic carcinomas (n = 5), cystic metastasized oropharyngeal carcinomas (n = 97), and carcinomas of unknown primary (n = 51). The study was conducted as a retrospective case series study with comparison.

RESULTS

The patients with bronchogenic carcinomas differed significantly in age and in the number of involved lymph nodes compared with the cystic metastasized oropharyngeal carcinoma (and carcinoma of unknown primary) patients. Regular histologic wall structures were only observed in the bronchogenic carcinomas and branchial cleft cysts. Solitary cytokeratin-7 staining was only observed in the bronchogenic carcinomas, and all of the bronchogenic carcinomas were p16 negative.

CONCLUSIONS

The existence of bronchogenic carcinoma seems to be plausible based on clinical findings. Cytokeratin-7 and p16 staining might be helpful in the diagnostic workflow.

LEVEL OF EVIDENCE

4 Laryngoscope, 126:638-642, 2016.

A cornucopia of screening and diagnostic techniques for human papillomavirus associated cervical carcinomas

Cervical carcinoma is one of the major consequences of human papillomavirus (HPV) infections. Although HPV infections of cervix do not always progress to cancer, 90% cases of cervical cancer have been found associated with high risk HPV (hrHPV) infection. Usually, HPV infection is asymptomatic; however, this asymptomatic infection can cause abnormal changes in cervix ultimately leading to cancer development. These changes can be detected by the application of screening tests at regular time intervals. For this purpose, morphological, cytological, and DNA based techniques are available. Nevertheless, abnormal screening tests have only the predictive value for precancerous lesions and thus require further evaluation which is usually done by using diagnostic techniques. So far, colposcopy and histological examination alone were considered as the gold standards for cervical cancer diagnosis. Currently, some tests based on expression level of host cell biomarkers are also being used along with histology for diagnostic purpose. Albeit, these tests have significant specificity and sensitivity values but they are unable to suggest a particular viral genotype involved in infection. Diagnostic methods such as PCR, HPV genotyping assays, microarray, and mRNA based assays are useful to predict the genotypes as well as the quantity of viral load in a host cell. Similarly, these diagnostic procedures have high specificity and sensitivity ranges. However, only few of them are practiced commonly, as approval of these tests as routine diagnostic tests requires clinical validation and cost effectiveness.

The protective effect of p16(INK4a) in oral cavity carcinomas: p16(Ink4A) dampens tumor invasion-integrated analysis of expression and kinomics pathways

A large body of evidence shows that p16(INK4a) overexpression predicts improved survival and increased radiosensitivity in HPV-mediated oropharyngeal squamous cell carcinomas.(OPSCC). Here we demonstrate that the presence of transcriptionally active HPV16 in oral cavity squamous cell carcinomas does not correlate with p16(INK4a) overexpression, enhanced local tumor immunity, or improved outcome. It is interesting that HPV-mediated oropharyngeal squamous cell carcinomas can be categorized as having a 'nonaggressive' invasion phenotype, whereas aggressive invasion phenotypes are more common in HPV-negative squamous cell carcinomas. We have developed primary cancer cell lines from resections with known pattern of invasion as determined by our validated risk model. Given that cell lines derived from HPV-mediated oropharyngeal squamous cell carcinomas are less invasive than their HPV-negative counterparts, we tested the hypothesis that viral oncoproteins E6, E7, and p16(INK4a) can affect tumor invasion. Here we demonstrate that p16(INK4a) overexpression in two cancer cell lines (UAB-3 and UAB-4), derived from oral cavity squamous cell carcinomas with the most aggressive invasive phenotype (worst pattern of invasion type 5 (WPOI-5)), dramatically decreases tumor invasiveness by altering expression of extracellular matrix remodeling genes. Pathway analysis integrating changes in RNA expression and kinase activities reveals different potential p16(INK4a)-sensitive pathways. Overexpressing p16(INK4a) in UAB-3 increases EGFR activity and increases MMP1 and MMP3 expression, possibly through STAT3 activation. Overexpressing p16(INK4a) in UAB-4 decreases PDGFR gene expression and reduces MMP1 and MMP3, possibly through STAT3 inactivation. Alternatively, ZAP70/Syk might increase MUC1 phosphorylation, leading to the observed decreased MMP1 expression.

Vascular endothelial growth factor receptor isoforms: are they present in oral squamous cell carcinoma?

PURPOSE

Although the clinical importance of vascular endothelial growth factor (VEGF) overexpression in oral squamous cell carcinoma (OSCC) has been investigated, there are limited data about the overexpression of VEGF receptors (VEGF-Rs) and their clinical importance. VEGF-R isoforms have proven influence on proliferation rates, metastasis, and survival in different neoplasms. This study was conducted to investigate VEGF-R expression levels in OSCC samples and to identify any clinical relevance.

MATERIALS AND METHODS

A retrospective cohort study design (n = 50) was used. Clinical data were gathered from patient charts. Validated immunohistochemical methods were applied to determine VEGF-R isoform expression by tumor cells. Descriptive and inferential statistics with respect to the variable scale were computed. The significance level was set at a P value less than or equal to .05.

RESULTS

This study found overexpression of different VEGF-R isoforms in 88% of examined specimens. Statistically important associations were detected between overexpression of specific VEGF-Rs and tumor size, neck node metastasis, and tumor-associated death. Furthermore, a history of common OSCC risk factors (smoking and alcohol consumption) were found considerably more often in patients whose OSCC specimens displayed VEGF-R overexpression.

CONCLUSION

These findings show that VEGF-R overexpression occurs frequently in OSCC and could have clinical implications.

Oral squamous cell carcinoma associated with proliferative verrucous leukoplakia compared with conventional squamous cell carcinoma--a clinical, histologic and immunohistochemical study

OBJECTIVE

Proliferative verrucous leukoplakia (PVL), a potentially malignant disorder, often undergoes malignant transformation to oral squamous cell carcinoma. The aim of our study was to document and compare the histologic, immunohistochemical, and clinical features and the survival rates of carcinoma arising in patients with PVL (p-scca) with conventional squamous cell carcinoma (c-scca) in order to determine if p-scca should be categorized as a separate clinical entity.

MATERIALS AND METHODS

A retrospective review of 11 patients with PVL, 38 with p-scca tumors and 49 with c-scca tumors: buccal mucosa (n = 28) and gingiva or palate (n = 21). Immunohistochemistry was performed by using antibodies directed against p16, p53, and ki67.

RESULTS

P-scca had lower clinical stage (P = .0001), smaller tumor size (P = .0033), no lymph node metastasis (P = .0002) or distant metastasis (P = .05), and better short term (P = .03), but not long term (P = .12) survival. Microscopically, p-scca tumor thickness was significantly less (P = .0001). P-53 overexpression was more common in p-scca (P = .0043) but not ki67 or p16 overexpression.

CONCLUSIONS

P-scca, compared with c-scca, presented with significantly better prognostic factors and short-term survival rates and longer duration of disease. Our results suggest that p-scca may represent a distinct entity, which may have practical implications when deciding on treatment. Further studies on a larger cohort of patients are recommended.

Oral squamous cell carcinoma positive for p16/human papilloma virus in post allogeneic stem cell transplantation: 2 cases and review of the literature

Complications of allogeneic hematopoietic stem cell transplantation (allo-HSCT) includes the risk of secondary malignancies. This may be related to mechanisms including radiation and chemotherapy regimens, chronic graft-versus-host disease, inflammation, and prolonged imunosuppression. Oral squamous cell carcinoma (OSCC) is a complication associated with chronic graft-versus-host disease after allo-HSCT. Although human papillomavirus (HPV) is known to be associated with OSCC, the role of HPV in development of OSCC in post-HSCT patients has not been studied. We identified 2 cases of OSCC in allo-HSCT recipients. Both biopsy specimens tested positive for p16(INK4A), a surrogate marker for HPV. We propose that the association of OSCC and HPV in patients after allo-HSCT may not be incidental. Clinical implications of these cases may imply the need for a HPV screening, early intervention, and consideration of anti-HPV vaccination in this population. The effectiveness of such interventions could be validated in a prospective clinical study.

Impact of human papilloma virus infection on the response of head and neck cancers to anti-epidermal growth factor receptor antibody therapy

Infection with human papillomaviruses (HPVs) characterizes a distinct subset of head and neck squamous cell cancers (HNSCCs). HPV-positive HNSCC preferentially affect the oropharynx and tonsils. Localized HPV-positive HNSCCs have a favorable prognosis and treatment outcome. However, the impact of HPV in advanced or metastatic HNSCC remains to be defined. In particular, it is unclear whether HPV modulates the response to cetuximab, an antibody targeting the epidermal growth factor receptor (EGFR), which is a mainstay of treatment of advanced HNSCC. To this end, we have examined the sensitivity of HPV-positive and -negative HNSCC models to cetuximab and cytotoxic drugs in vitro and in vivo. In addition, we have stably expressed the HPV oncogenes E6 and E7 in cetuximab-sensitive cancer cell lines to specifically investigate their role in the antibody response. The endogenous HPV status or the expression of HPV oncogenes had no significant impact on cetuximab-mediated suppression of EGFR signaling and proliferation in vitro. Cetuximab effectively inhibited the growth of E6- and E7-expressing tumors grafted in NOD/SCID mice. In support, formalin-fixed, paraffin-embedded tumor samples from cetuximab-treated patients with recurrent or metastatic HNSCC were probed for p16^INK4a expression, an established biomarker of HPV infection. Response rates (45.5% versus 45.5%) and median progression-free survival (97 versus 92 days) following cetuximab-based therapy were similar in patients with p16^INK4A-positive and p16^INK4A-negative tumors. In conclusion, HPV oncogenes do not modulate the anti-EGFR antibody response in HSNCC. Cetuximab treatment should be administered independently of HPV status.

Clinicopathologic features of oral squamous cell carcinoma: do they vary in different age groups?

PURPOSE

To analyze clinicopathologic parameters of oral squamous cell carcinoma (OSCC) in different age groups. We hypothesized that clinical and pathologic parameters of OSCCs will vary in different age groups.

MATERIALS AND METHODS

A retrospective cohort study was performed. All patients who were treated for a primary manifestation of OSCC at a single institution from 2001 to 2012 were reviewed and allocated to predefined age groups (predictor variable) as follows: young (≤40 years), middle-aged (40-80 years), and very elderly (≥80 years). The following outcome variables were recorded: demographic parameters, classic risk factors, tumor location and size, neck node involvement, histopathologic and therapeutic details, and association with human papillomavirus (HPV). The descriptive statistics were computed. Parametric and nonparametric tests were used for additional analysis. The significance level was set at P < .05.

RESULTS

We reviewed 739 patients and identified 11 (1.4%) young (mean age 34.2 ± 2.8 years) and 17 (2.3%) very elderly patients (mean age 83.1 ± 1.2 years). The predilection site for OSCC was the oral tongue (63%) in young patients, the floor of the mouth (52%) in middle-aged patients, and the alveolar process (60%) in very elderly patients. One patient in the young group (9%) and 8 patients in the very elderly group (47%) had been exposed to risk factors; however, all of the examined middle-aged patients had had such exposure. The association of OSCC with HPV was distributed equally among the age groups. No age-related differences in the histopathologic parameters of OSCC were found.

CONCLUSIONS

The features of OSCC that vary at different ages are the anatomic predilection site and the association with classic risk factors. HPV was not an age-related independent risk factor for OSCC development in the present study.

A literature review on oral basaloid squamous cell carcinomas, with special emphasis on etiology

In the recent years, basaloid squamous cell carcinomas (BSCCs) have gained attention because of (1) observation of a relative increase in the number of tumors arising particularly in head and neck sites, (2) identification of human papillomavirus (HPV) in BSCCs arising predominantly in the oropharynx, and (3) controversies that exist regarding the biological aggressiveness of the tumor. The objective of the present review was to address the issues mentioned above by focusing primarily on oral BSCCs, using literature that has been published in the English language up to 2013. According to the literature review, oral BSCCs were found to be relatively more common in elderly patients with a mean age of 64 years. A male predominance with a male/female ratio of 3:1 was observed. The predominant site was the tongue, with almost half of the reported cases occurring at this site, followed by the floor of the mouth and palate. With reference to habit history, majority were found to be tobacco and alcohol users. However, only 3 studies revealed data on HPV status of purely oral BSCC, and according to the results of these studies, of the 17 tumors tested, 4 had harbored high-risk HPV. Furthermore, most oral BSCCs were in an advanced clinical stage, namely, stage III or IV with T3 or T4 lesions and cervical lymph node metastasis at initial presentation, whereas 41% of patients had presented with local recurrences and 45% had died of the disease. In conclusion, although, the present literature review found enough evidence to consider tobacco and alcohol as risk factors for the development of oral BSCC, steps should be taken to fill the gap in our knowledge that exist with reference to contribution of oncoviruses, particularly HPV in the etiology of oral BSCC.