Human papillomavirus infection and biomarkers in sinonasal inverted papillomas: clinical significance and molecular mechanisms

International Consensus Statement on Allergy and Rhinology: Sinonasal Tumors

BACKGROUND

Sinonasal neoplasms, whether benign and malignant, pose a significant challenge to clinicians and represent a model area for multidisciplinary collaboration in order to optimize patient care. The International Consensus Statement on Allergy and Rhinology: Sinonasal Tumors (ICSNT) aims to summarize the best available evidence and presents 48 thematic and histopathology-based topics spanning the field.

METHODS

In accordance with prior International Consensus Statement on Allergy and Rhinology documents, ICSNT assigned each topic as an Evidence-Based Review with Recommendations, Evidence-Based Review, and Literature Review based on the level of evidence. An international group of multidisciplinary author teams were assembled for the topic reviews using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses format, and completed sections underwent a thorough and iterative consensus-building process. The final document underwent rigorous synthesis and review prior to publication.

RESULTS

The ICSNT document consists of four major sections: general principles, benign neoplasms and lesions, malignant neoplasms, and quality of life and surveillance. It covers 48 conceptual and/or histopathology-based topics relevant to sinonasal neoplasms and masses. Topics with a high level of evidence provided specific recommendations, while other areas summarized the current state of evidence. A final section highlights research opportunities and future directions, contributing to advancing knowledge and community intervention.

CONCLUSION

As an embodiment of the multidisciplinary and collaborative model of care in sinonasal neoplasms and masses, ICSNT was designed as a comprehensive, international, and multidisciplinary collaborative endeavor. Its primary objective is to summarize the existing evidence in the field of sinonasal neoplasms and masses.

Tumors of the Nose and Paranasal Sinuses: Promoting Factors and Molecular Mechanisms-A Systematic Review

Sinonasal neoplasms are uncommon diseases, characterized by heterogeneous biological behavior, which frequently results in challenges in differential diagnosis and treatment choice. The aim of this review was to examine the pathogenesis and molecular mechanisms underlying the regulation of tumor initiation and growth, in order to better define diagnostic and therapeutic strategies as well as the prognostic impact of these rare neoplasms. A systematic review according to Preferred Reporting Items for Systematic Review and Meta-Analysis criteria was conducted between September and November 2022. The authors considered the three main histological patterns of sinonasal tumors, namely Squamous Cell Carcinoma, Intestinal-Type Adenocarcinoma, and Olfactory Neuroblastoma. In total, 246 articles were eventually included in the analysis. The genetic and epigenetic changes underlying the oncogenic process were discussed, through a qualitative synthesis of the included studies. The identification of a comprehensive model of carcinogenesis for each sinonasal cancer subtype is needed, in order to pave the way toward tailored treatment approaches and improve survival for this rare and challenging group of cancers.

Loss of p16 expression is a risk factor for recurrence in sinonasal inverted papilloma

BACKGROUND

The purpose of this study was to evaluate p16, p53, EGFR, pEGFR protein expression and HPV infection as possible markers of tumor progression in a series of sinonasal inverted papilloma (SNIP) and sinonasal squamous cell carcinoma (SNSCC).

METHODS

A series of 49 SNIP, 11 SNSCC associated with SNIP (SNIP-SNSCC) and 52 SNSCC not associated with SNIP were analyzed for p16, p53, EGFR, and phosphorylated EGFR (pEGFR) expression by immunohistochemistry. Human papillomavirus (HPV) infection status was evaluated by DNA-PCR. Results were correlated to clinical and follow-up data.

RESULTS

Reduced or loss of p16 expression was observed in 18% SNIP, 64% SNIP-SNSCC and 87% of SNSCC. Reduced or loss p16 staining in SNIP correlated with shorter recurrent SNIP-free follow-up. In contrast, p16 expression was not predictive of recurrent SNSCC in cases with SNIP-SNSCC and SNSCC. P53, EGFR, and pEGFR expression did not differ between the tumor groups, nor were they related to recurrent SNIP-free follow-up or recurrent SNSCC. Oncogenic HPV types 16 and 18 were detected in 5% of SNIP and 18% of SNIP-SNSCC, but not in SNSCC. There was no correlation between HPV infection and >70% p16 immunostaining.

CONCLUSIONS

HPV infection appears to play a minor role in SNIP and SNSCC and p16 immunostaining does not appear a valid surrogate marker for HPV. However, reduced or loss p16 expression may have prognostic value as a risk marker for recurrent SNIP.

Association between human papillomavirus infection and malignant transformation of sinonasal inverted papilloma: A systematic review and meta-analysis

PURPOSE

Although sinonasal inverted papilloma malignant transformation has not been entirely understood, some studies have suggested that human papillomavirus acts as a potential oncogenic agent in the progression of sinonasal inverted papilloma to squamous cell carcinoma. The purpose of this study was to assess the association between human papillomavirus infection and sinonasal inverted papilloma transformation, taking also into account human papillomavirus types and their distribution in different geographic areas.

MATERIALS AND METHODS

The literature from the last 25 years was examined. The systematic review and meta-analysis were performed according to the PRISMA guidelines.

RESULTS

A total of 163 malignant sinonasal inverted papilloma and 961 non-malignant sinonasal inverted papilloma were included in the overall analysis. From this sample it was possible to recognize a statistically significant increase in risk of malignancy of sinonasal inverted papilloma for human papillomavirus infection (OR = 2.43, 95 % CI: 1.45-4.08, I2 = 14.0 %). A positive association for patients with high-risk human papillomavirus types was noted (OR = 10.20, 95 % CI: 3.66-28.42, I2 = 15.9 %). In all the 3 geographical areas analyzed the presence of high-risk human papillomavirus significantly increased the probability of malignant transformation.

CONCLUSIONS

High-risk human papillomavirus infection plays a key role in the malignant transformation of sinonasal inverted papilloma and its research during histological examination can be of paramount importance. More prospective studies are needed to help further tease out this association.

Etiology of sinonasal inverted papilloma: An update

Objective

Sinonasal inverted papilloma (IP) and its clinical features have been widely studied, but there are few studies delving into its etiology and risk factors. A narrative review was conducted to summarize a contemporary understanding of the potential etiologies of IP, including immunologic/inflammatory, viral, genetic, and environmental causes.

Study Design

Review.

Methods

A MEDLINE search was conducted through August 11, 2021, focusing on studies investigating the etiology and risk factors for sinonasal IP and its malignant transformation.

Results

High‐ and low‐risk human papillomavirus have been connected with the formation of IP, but conflicting evidence exists regarding their role. Occupational and industrial exposures may also contribute to IP formation, while smoking may increase the odds of malignant progression. Exon 20 mutations in EGFR are an active area of research in IP with mixed evidence. Finally, several cell cycle and angiogenic factors such as Ki67, VEGF, and Akt/mTOR have been implicated in the development and progression of IP.

Conclusion

There continues to be conflicting evidence around the development of IP, but significant progress has been made in recent years. Further study is needed for all these potential etiologies to elucidate risk factors and therapeutic strategies.

Keeping in Mind Its Synchronous Features, Is Sinonasal Inverted Papilloma Always Benign?

Sinonasal inverted papilloma (SNIP) is a rare benign tumor of paranasal sinuses. SNIP is known to be locally aggressive, with high rates of recurrence and a high potential for malignant transformation. We present a patient who presented with right-sided cheek pain and swelling for two weeks. The initial biopsy revealed SNIP. However, postoperative histopathology examination results revealed synchronous squamous cell carcinoma (SCC) with sinonasal inverted papilloma. Although the initial biopsy result showed a benign lesion, the aggressive features such as bony destruction and orbital involvement in computed tomography scan should raise a suspicion of a malignant lesion. Imaging features of SNIP from synchronous SCC are discussed.

Towards a Molecular Classification of Sinonasal Carcinomas: Clinical Implications and Opportunities

Simple Summary

In recent years, there have been several molecular and immunohistochemical additions to the pathologic diagnosis of sinonasal malignancies that could facilitate the identification of clinically relevant groups of sinonasal malignancies. Molecular profiling is progressively integrated in the histopathologic classification of sinonasal carcinomas, and it is likely to influence the management of these tumors in the near future. In this article we review the recent literature on molecular analysis and/or subtyping of sinonasal carcinomas and we discuss the possible clinical implications of a classification of sinonasal tumors based on their molecular features.

Abstract

Sinonasal carcinomas are a heterogeneous group of rare tumors, often with high-grade and/or undifferentiated morphology and aggressive clinical course. In recent years, with increasing molecular testing, unique sinonasal tumor subsets have been identified based on specific genetic alterations, including protein expression, chromosomal translocations, specific gene mutations, or infection by oncogenic viruses. These include, among others, the identification of a subset of sinonasal carcinomas associated with HPV infection, the identification of a subset of squamous cell carcinomas with EGFR alterations, and of rare variants with chromosomal translocations (DEK::AFF2, ETV6::NTRK and others). The group of sinonasal adenocarcinomas remains very heterogeneous at the molecular level, but some recurrent and potentially targetable genetic alterations have been identified. Finally, poorly differentiated and undifferentiated sinonasal carcinomas have undergone a significant refinement of their subtyping, with the identification of several new novel molecular subgroups, such as NUT carcinoma, IDH mutated sinonasal undifferentiated carcinoma and SWI/SNF deficient sinonasal malignancies. Thus, molecular profiling is progressively integrated in the histopathologic classification of sinonasal carcinomas, and it is likely to influence the management of these tumors in the near future. In this review, we summarize the recent developments in the molecular characterization of sinonasal carcinomas and we discuss how these findings are likely to contribute to the classification of this group of rare tumors, with a focus on the potential new opportunities for treatment.

Clinicopathologic Analysis of Sinonasal Inverted Papilloma, with Focus on Human Papillomavirus Infection Status

Sinonasal inverted papilloma (SNIP) can recur; however, the factors related to tumor recurrence remain unclear. This study aimed to analyze risk factors, including human papillomavirus (HPV) infection, as well as other factors associated with SNIP recurrence. Thirty-two patients who were diagnosed with SNIP and underwent surgery between 2010 and 2019 were enrolled: 24 men and 8 women, with a mean age of 59.2 years. The mean follow-up was 57.3 months. Demographics and information about history of smoking, diabetes mellitus (DM), hypertension, allergic rhinitis, alcohol consumption, tumor stage, surgical approach, and recurrence were reviewed retrospectively. Specimens were investigated using polymerase chain reaction to detect HPV DNA (high-risk subtypes: 16, 18, 31, 33, 35, 52b, and 58; low-risk subtypes: 6 and 11). Seven patients (21.9%) experienced recurrence. HPV DNA was detected in five (15.6%) patients (high-risk subtypes, n = 2; low-risk subtypes, n = 3). Patients with recurrence of SNIP had a higher proportion of young adults and displayed higher rates of HPV infection, DM, and advanced tumor stage than those without recurrence. HPV infection, young adulthood, DM, and advanced tumor stage could be associated with a high recurrence rate, which suggests that patients with these risk factors could require close follow-up after surgery.

Role of High-Risk HPV Detected by PCR in Malignant Sinonasal Inverted Papilloma: A Meta-Analysis

INTRODUCTION

Prior studies suggest that there may be a link between human papillomavirus (HPV) infection and malignant sinonasal inverted papilloma (SNIP). This systematic review and meta-analysis was performed to further evaluate this potential association.

STUDY DESIGN

Systematic review with meta-analysis.

METHODS

The Medline and Embase databases were used to identify case-control studies reporting the risk of malignant SNIP in patients with high-risk HPV subtypes identified by polymerase chain reaction (PCR). Meta-analysis was performed to determine pooled odds ratios (ORs) and 95% confidence intervals (CI).

RESULTS

Twenty-one studies were identified, including a total of 841 subjects with SNIP. Seventeen studies were included in the final analysis, as four studies did not have any HPV-positive tumors in either group. A total of 56 malignant SNIP and 551 benign SNIP were ultimately identified. The pooled log-OR was 1.80 (95% CI: 1.03-2.57) for all high-risk HPV subtypes. Stratification by high-risk HPV subtype showed a log-OR of 1.67 (95% CI: 0.88-2.46) for HPV-16 and log-OR of 2.68 (95% CI: 1.30-4.05) for HPV-18.

CONCLUSION

Infection with high-risk HPV subtypes may be associated with an increased risk of malignant SNIP. HPV-18 showed the greatest overall average effect size of the common high-risk subtypes.

LEVEL OF EVIDENCE

n/a Laryngoscope, 2021.

TP53 mutations and CDKN2A mutations/deletions are highly recurrent molecular alterations in the malignant progression of sinonasal papillomas

Sinonasal papillomas are benign epithelial tumors of the sinonasal tract that are associated with a synchronous or metachronous sinonasal carcinoma in a subset of cases. Our group recently identified mutually exclusive EGFR mutations and human papillomavirus (HPV) infection in inverted sinonasal papillomas and frequent KRAS mutations in oncocytic sinonasal papillomas. We also demonstrated concordant mutational and HPV infection status in sinonasal papilloma-associated sinonasal carcinomas, confirming a clonal relationship between these tumors. Despite our emerging understanding of the oncogenic mechanisms driving formation of sinonasal papillomas, little is currently known about the molecular mechanisms of malignant progression to sinonasal carcinoma. In the present study, we utilized targeted next-generation DNA sequencing to characterize the molecular landscape of a large cohort of sinonasal papilloma-associated sinonasal carcinomas. As expected, EGFR or KRAS mutations were present in the vast majority of tumors. In addition, highly recurrent TP53 mutations, CDKN2A mutations, and/or CDKN2A copy-number losses were detected; overall, nearly all tumors (n = 28/29; 96.6%) harbored at least one TP53 or CDKN2A alteration. TERT copy-number gains also occurred frequently (27.6%); however, no TERT promoter mutations were identified. Other recurrent molecular alterations included NFE2L2 and PIK3CA mutations and SOX2, CCND1, MYC, FGFR1, and EGFR copy-number gains. Importantly, TP53 mutations and CDKN2A alterations were not detected in matched sinonasal papillomas, suggesting that these molecular events are associated with malignant transformation. Compared to aerodigestive tract squamous cell carcinomas from The Cancer Genome Atlas (TCGA) project, sinonasal papilloma-associated sinonasal carcinomas have a distinct molecular phenotype, including more frequent EGFR, KRAS, and CDKN2A mutations, TERT copy-number gains, and low-risk human papillomavirus (HPV) infection. These findings shed light on the molecular mechanisms of malignant progression of sinonasal papillomas and may have important diagnostic and therapeutic implications for patients with advanced sinonasal cancer.

HPV in the malignant transformation of sinonasal inverted papillomas: A meta-analysis

OBJECTIVES

To date, there is still a significant debate on the role of human papilloma virus (HPV) infection in transformation of inverted papillomas (IPs) to squamous cell carcinoma (SCC). This study was designed to determine if the presence of HPV in a sinonasal IP increases the risk of malignant transformation to IPSCC.

METHODS

Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, 19 high-quality case-control and cohort studies with tissue-diagnosed IP or IPSCC and HPV diagnosis were analyzed. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using the Mantel-Haenszel method with correction for random effects. Subgroup, publication bias and a sensitivity analyses were also performed.

RESULTS

Nineteen studies with minimal bias met the inclusion criteria for quality and identified HPV infection in an IP. The pooled data revealed a strong association with progression to malignancy with an unweighted, pooled OR of 2.38 (CI₉₅ 1.47 to 3.83) and a weighted OR of 2.80 (CI₉₅ 1.42 to 5.51). Sensitivity analysis revealed that no single study contributed significantly to our pooled OR calculations (ORs 2.52 to 3.57). Subgroup analyses stratified by publication date, nucleic acid target, HPV detection method and type, sample size, and region all demonstrated a positive association of HPV with IPSCC.

CONCLUSIONS

There appears to be a significant association between HPV infection and malignant transformation of IPs. While HPV testing is not currently the standard of care for IPs, these data suggest a link between the two and suggest further studies should be performed to identify a link between the virus and malignant transformation.

Impact of human papillomaviruses (HPV) on recurrence rate and malignant progression of sinonasal papillomas

Sinonasal papillomas are characterized by their potential for frequent recurrences and malignant progression. Currently, the role of human papillomavirus (HPV) infection in sinonasal papillomas is unclear. A study was conducted to elucidate the impact of HPV infection on recurrence and malignant progression of sinonasal papillomas. One hundred and seven patients with 151 tumors could be examined. One hundred and one patients suffered from benign papilloma, mostly inverted papillomas (IP); six patients suffered from carcinomas in situ and squamous cell carcinomas (SCC) ex-IP. Recurrent IP were more often HPV-positive than non-recurrent tumors (38.8% vs. 60%-65%). Low-risk (LR) HPV infection (especially HPV 6) increased the risk of tumor recurrences (p = 0.0385 and p = 0.0556, respectively). IP and oncocytic papillomas (both lesions are known for their malignant potential) were more often high-risk (HR) HPV-positive (15.5% and 16.7%) than fungiform papilloma (which usually does not progress to carcinoma). CIS and SCC ex-IP displayed higher HPV rates than benign IP (83.3% vs. 38.8%), especially higher rates of HR-HPV (66.7% vs. 23.8%, p = 0.0415). Data from this study endorse the hypothesis that recurrence of sinonasal papillomas is promoted by LR-HPV infection and that malignant progression of IP is promoted by HR-HPV infection.

Expression of Sp100 Protein in Human Papillomavirus-Associated Sinonasal Inverted Papilloma

OBJECTIVE

Sinonasal inverted papilloma (SNIP) is a benign tumor characterized by an aggressive growth, a tendency to recur, and an association with malignancy. However, the precise etiology of SNIP is still unknown. The objective of this study was to identify the expression pattern of speckled protein 100 (Sp100) in the malignant transformation (MT) of SNIP and its correlation with human papillomavirus (HPV)-16 and HPV-18 infections and other clinical features. This would further help in understanding the possible mechanisms for the development of SNIP.

METHODS

Individual nasal mucosa specimens from 40 patients (25 males and 15 females) and 10 inferior turbinate specimens as controls were included in the present study. The samples were divided into several sections for histopathological examination, HPV DNA detection, and immunohistochemical staining.

RESULTS

We observed that as SNIP progressed, the Sp100 protein expression was gradually downregulated, and SP100 localization changed from nucleus to the cytoplasm. Positive rate of HPV infection in the SNIP with MT group was higher than that in the other groups, and Sp100 expression was correlated to HPV infections and SNIP with MT. However, no correlation was observed between Sp100 expression and clinical features, such as age, gender, and smoking.

CONCLUSION

Positive rate of HPV infection is high in the SNIP with MT and has a correlation with Sp100 expression. In addition, the expression of Sp100 is downregulated in SNIP with MT, and Sp100 may play a role in the progression of SNIP.

COX-2 Overexpression in Schneiderian Papillomas

Background

Schneiderian papillomas (SP) are aggressive sinonasal tumors that occasionally extend into areas that are surgically unresectable.

Objective

evaluate the signifcance of cyclo-oxygenase-2 (COX-2) expression in SP.

Methods

Immunohistochemistry for COX-2 was performed on SP samples and middle turbinates from chronic rhinosinusitis without nasal polyps controls obtained during surgical resection between 2009–2017. A positive stain was defined as having 10% or more cells exhibiting diffuse immunoreactivity. Comparisons were performed using Fisher Exact tests, t-tests, and ANOVA.

Results

The study included 67 tumor samples and 9 controls from two academic institutions. The mean age of the SP group was 55.4 years and 53.2 years in the control group (p = 0.71). Thirty-nine (58.2%) SP patients had previous surgery compared to 1 (11.1%) in the control group (p = 0.01). The most common tumor attachment sites were the maxillary (47.8%) and ethmoid (25.4%) sinuses. Fifteen (22.4%) SP samples stained strongly positive for COX-2 and 24 (35.8%) stained weakly positive compared to no positive stains in the control group (p < 0.01). When stratified by COX-2 intensity, there were no statistically significant differences in gender, smoking history, history of previous sinus surgery, site of attachment, papilloma subtype, or future recurrence between SP samples.

Conclusion

COX-2 was overexpressed in 58.2% of SP cases, and strongly positive in 22.4% of cases, compared to no positive staining among controls. No significant differences in COX-2 expression were observed between SP subtypes or recurrent tumors. Further studies are warranted to evaluate COX-2 as a possible therapeutic target in tumors that overexpress the enzyme.

Association Between Human Papilloma Virus Infection and Malignant Sinonasal Inverted Papilloma

OBJECTIVE

This systematic review and meta-analysis aimed to evaluate the risk of malignant sinonasal inverted papilloma (SNIP) according to the type of human papilloma virus (HPV) infection.

METHODS

The databases of PubMed, EmBase, and Web of Science were searched for studies that reported the risk of malignant SNIP in patients infected by specific types of HPV. The quantitative analyses for pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated.

RESULTS

Twenty-six molecular epidemiological studies that recruited a total of 900 patients with SNIP were selected for the final meta-analysis. The summary ORs indicated that HPV-6 (OR: 2.02; 95% CI: 0.47-8.61; P = .343), HPV-11 (OR: 0.86; 95% CI: 0.26-2.89; P = .806), and HPV-6/11 (OR: 1.44; 95% CI: 0.59-3.53; P = .426) infections were not associated with the risk of malignant SNIP. However, the risk of malignant SNIP was increased in patients infected with HPV-16 (OR: 8.51; 95% CI: 3.36-21.59; P < .001), HPV-11/16 (OR: 7.95; 95% CI: 1.13-56.01; P = .038), HPV-18 (OR: 23.26; 95% CI: 5.27-102.73; P < .001), and HPV-16/18 (OR: 24.34; 95% CI: 5.74-103.18; P < .001).

CONCLUSIONS

This study found that patients infected with HPV types 16, 11/16, 18, and 16/18 were associated with an increased risk of malignant SNIP. However, patients infected with HPV types 6, 11, and 6/11 did not have a significant risk of malignant SNIP. Laryngoscope, 131:1200-1205, 2021.

The role of human papillomavirus in the pathogenesis of sinonasal inverted papilloma: a narrative review

Sinonasal inverted papillomas (IPs) are rare tumours arising from the nasal epithelial mucosa. Most lesions are benign, but a subset of IPs progress to dysplasia and squamous cell carcinoma. Although the epidemiology and clinical features of IPs are well known, the pathogenesis is still unclear. Given the established role of human papillomaviruses (HPVs) in the formation of other mucosal tumours including cervical and oropharyngeal cancer, some have suggested the virus may play a role in IP development. However, the association between HPV and IPs has not yet been proven, and the variable detection of HPV DNA in IPs has cast uncertainty on whether the virus plays a major role in pathogenesis. In this review, we summarize early clinical reports and synthesize recent studies that may elucidate the association between HPV and IPs. We also discuss the role HPV may have in the progression of benign IP to dysplasia and malignancy, as well as potential pathological mechanisms. We hope that synthesizing the initial and recent studies on this topic will not only lead to a better understanding of research in the role of HPV in IP development, but also help guide and contextualize future studies.

Sinonasal inverted schneiderian papilloma presenting as a large intraoral lesion

Sinonasal inverted schneiderian papilloma (ISP) is a rare tumour, which almost exclusively arises from the mucosa lining, the nasal cavity and the paranasal sinuses. The tumour in its early stages presents as an asymptomatic mass, which may be discovered during routine examination. Large lesions usually measure a few millimetres to centimetres in size and show symptoms such as nasal blockade, recurrent sinusitis, postnasal drip, anosmia, epistaxis, facial pain and headache. Lesion presenting as a large oral mass is extremely rare and may cause diagnostic dilemma, resulting in misdiagnosis. This report describes a rare case of ISP presenting as large intraoral lesion, with wide area of facial skeletal involvement. Diagnosis and management of the pathology has also been highlighted.

Identification of Rare and Common HPV Genotypes in Sinonasal Papillomas

Sinonasal papillomas are rare, usually benign tumors arising from the Schneiderian membrane. Human papillomaviruses (HPV) can infect differentiating skin and mucosal cells and can induce uncontrolled growth patterns. Their effect on development of sinonasal papillomas has been discussed controversially in recent years. A monocentric, retrospective study was conducted to investigate histopathologic features of sinonasal papillomas and to establish an assay for HPV detection and genotyping in papillomas. Schneiderian papillomas are divided into three groups according to histopathologic features: the largest group are inverted papillomas, followed by fungiform (exophytic) and oncocytic papillomas. HPV screening was performed with high sensitivity by PCR employing My09/11 and 125 consensus primers. Adding a third primer pair (GP5+/GP6+) d increase sensitivity. Reverse hybridization microarrays achieved HPV genotyping better than pyrosequencing in our setting. HPV infection rates were higher in papillomas (46.7%) than infection rates reported for healthy mucosa (up to 13%). P16(INK4a) was not a reliable surrogate marker for HPV infection in sinonasal papillomas. Data from our study endorses the hypothesis that HPV infection promotes formation of sinonasal papillomas. However, apart from HPV genotypes that are frequently found in e.g. anogenital lesions (such as 6, 11, or 16), tissue samples of sinonasal papillomas also displayed infection with "rare" HPV types (such as 58, 42, 83, or 91).

How aggressive should resection of inverted papilloma be? Refinement of surgical planning based on the 25-year experience of a single tertiary center

BACKGROUND

The technique for transnasal endoscopic resection of inverted papilloma (IP) has evolved considerably during the last 20 years. The aim of the present study is to retrospectively analyze a single tertiary center series, with special emphasis on assessing the value of an "insertion-driven" technique on local control.

METHODS

Patients undergoing endoscopic resection for IP at the University of Brescia during the period 1991 to 2015 were enrolled. Site of origin and extension of IPs were assessed, together with presence of dysplasia and carcinoma in situ. Patients were divided in 3 cohorts: (1) historical cohort (treated before 2008), (2) contemporary "centripetal" cohort (treated with a traditional technique after 2008), and (3) contemporary "insertion-driven" cohort (treated with insertion-driven resection). Groups were compared considering outcomes and complications.

RESULTS

The series included 210 patients. Mean follow-up was 77.8 months. Thirty-eight (18.1%) patients showed precancerous changes. Maxillary involvement (p = 0.021) and presence of precancerous changes (p = 0.013) were significantly associated with a higher risk of recurrence. Five-year local control rate before and after 2008 was 95.1% and 90.5%, respectively. The insertion-driven cohort was associated with lower disease control when IPs involved the maxillary sinus. The rate of complications was 11.9%. The insertion-driven cohort was associated with a lower rate of major complications (p = 0.098).

CONCLUSION

Preoperative evidence of precancerous changes and/or involvement of maxillary sinus should prompt the surgeon to address the disease more aggressively (centripetal resection). Preoperative imaging and biopsy with abundant material may optimize the chance to stratify patients eligible for less or more conservative approaches.

High prevalence of human papillomavirus infection in sinonasal inverted papilloma: a single-institution cohort of patients

BACKGROUND

Both the prevalence of sinonasal inverted papilloma (IP) and the causal association with alpha-human papillomaviruses (alpha-HPVs) are controversial. In this study we aimed to determine HPV status in histologically selected, microdissected, formalin-fixed, and paraffin-embedded tissue samples of IP.

METHODS

HPV status was assessed retrospectively by polymerase chain reaction (PCR)-bead-based multiplex genotyping on tissue samples of patients diagnosed with IP and consecutively treated with endoscopic resection. Forty-one HPV genotypes were considered, distinguishing between high risk and low risk. HPV status was correlated with demographics and clinical variables. Sixty sinonasal IP tissue samples were initially considered. After exclusion of 5 cases due to insufficient quality/quantity of the samples, 55 patients were included for analysis.

RESULTS

HPV-DNA sequences were identified in 34 of 55 (61.8%) IPs, with a higher prevalence of high-risk than low-risk HPV genotypes (19 [55.9%] and 15 cases [44.1%], respectively). HPV16 strongly prevailed among the high-risk HPV cases (84.2%), and HPV54 prevailed among the low-risk HPV cases (53.3%). IPs with origin within the maxillary sinus were significantly associated with high-risk HPV (p = 0.019). No significant associations emerged between HPV status and demographics or clinical variables.

CONCLUSION

In a series of 55 IP tissue samples, HPV-DNA sequences were identified in 61.8% of cases, which differs from the data of previous investigations. Further case-control studies are advocated to confirm this prevalence in the Italian population addressed, and also to clarify any pathogenic involvement of HPV in the natural history of IPs.

Human Papillomavirus and Factors Associated with Recurrence in Sinonasal Inverted Papillomas from Poland and Spain

Sinonasal inverted papilloma (SNIP) is a benign but locally aggressive tumor that has a tendency for recurrence and malignant transformation. The role of human papillomavirus (HPV) in SNIP is controversial. To determine the HPV-DNA prevalence and type distribution in SNIP in two different geographic areas and assess the association between SNIP recurrence and HPV infection, as well as additional potential etiologic factors. Two retrospective cohorts of SNIP patients from Poland and Spain were evaluated. Demographic, tobacco/alcohol use, clinical, and follow-up data were collected. All samples were subject to histopathologic evaluation, DNA quality control, and HPV-DNA detection by PCR. HPV-DNA positive samples and a random sample of HPV-DNA negative cases were further subject to p16^INK4a analysis. Proportional-hazards models were used to evaluate the risk of recurrence by selected variables. Seventy-nine SNIP patients (46 from Spain diagnosed between 1995 and 2014, and 33 from Poland diagnosed between 2012 and 2017) were included in the study. HPV-DNA was detected in four patients (5.1%), two from each region, and all four were positive for the HPV11 subtype. Seventeen patients (21.5%) experienced recurrence, with a median time to recurrence of 14 months. No association was identified between lesional HPV-DNA positivity, toxic habits, Krouse stage, or malignant transformation and a higher risk of recurrence. The low prevalence of HPV-DNA in SNIPs suggests that HPV is not a main etiology for development of these lesions. With a lack of association between the evaluated factors and recurrence, further research with larger number of patients and additional biomarkers is warranted to further understand predisposing risk factors.

Prognostic factors and risk factors for development and recurrence of sinonasal papillomas: potential role of different HPV subtypes

PURPOSE AND METHODS

A retrospective study was conducted to identify and assess potential clinical and molecularbiological risk factors for development and recurrence of sinonasal papillomas (i.e. inverted (IP), fungiform (FP), and oncocytic papillomas (OCP)). Investigated risk factors included age, gender, tumor size and localization, tobacco smoking, regular alcohol consumption, essential hypertension, anticoagulant medication, allergies, surgical approach, and HPV infection. Risk factors were evaluated by regression analysis.

RESULTS

Apart from age and incomplete tumor resection, the recurrence of Schneiderian papillomas is independent of conventional risk factors. Patients in this study displayed higher HPV infections rates in IP (38.8%) and in FP (100%) than in healthy mucosa, which is reported 0-5.8% in Germany and central Europe. The proportion of HPV-positive IP decreased with advanced tumor stages: 100% HPV positivity of T1 IP (2/2), 40.9% of T2 IP (9/22), and 35.7% of T3 IP (20/56). Most commonly detected HPV types were HPV 6, 11, and 16; however, patients in this study also displayed HPV types that have rarely or not at all been described in sinonasal papillomas before, such as HPV 58, 42, 83, and 91. Recurrent sinonasal papillomas displayed higher rates of HPV infections than non-recurrent tumors.

CONCLUSIONS

Young age at initial diagnosis and incomplete tumor resection are risk factors for recurrence of sinonasal papillomas. Our data suggest that HPV infection supports development and/or perpetuation of sinonasal papillomas. Additionally, sinonasal papillomas seem to display a unique subset of HPV genotypes, including genotypes that have not often been described before.

Endoscopic Resection of Sinonasal Inverted Papilloma: A Multivariate Retrospective Analysis of Factors Affecting Recurrence and Persistence

Sinonasal inverted papilloma (IP) is the most common benign epithelial tumor in the nasal cavity and paranasal sinuses, with a worldwide incidence between 0.6 and 1.5/100 000 persons per year. However, only a few studies have investigated patient-dependent factors related to IP recurrence and persistence. According to available evidence, these factors are still debated, and results are contradictory. In this multicenter retrospective study, we analyzed the clinical records of 130 patients who were surgically treated for sinonasal IP to evaluate the factors affecting recurrence and persistence of IP and compared the curative rates of different surgical approaches. Our analysis showed that IP recurrence is strongly related to specific risk factors including incomplete surgical removal, stage of disease, site of the lesion, surgical technique, and malignancy rate. In conclusion, the recurrence of IP may be affected by several risk factors; these factors must be carefully considered during clinical evaluation and especially during the follow-up of patients with IP.

Human papillomavirus (HPV) and somatic EGFR mutations are essential, mutually exclusive oncogenic mechanisms for inverted sinonasal papillomas and associated sinonasal squamous cell carcinomas

Background

Inverted sinonasal (Schneiderian) papilloma (ISP) is a locally aggressive neoplasm often associated with sinonasal squamous cell carcinoma (SNSCC). While the etiology of ISP is not well understood, human papillomavirus (HPV) has been detected in a subset of cases. Our group recently identified activating somatic EGFR mutations in the majority of ISP and ISP-associated SNSCC. However, the relationship between EGFR mutations and HPV infection has not been explored.

Patients and methods

We evaluated 58 ISP and 22 ISP-associated SNSCC (including 13 patients with matched ISP/SNSCC samples), as well as 14 SNSCC without clinical or pathologic evidence of an associated ISP. Formalin-fixed, paraffin-embedded samples were evaluated for EGFR mutations using Sanger sequencing and for HPV infection using GP5+/GP6+ PCR. HPV subtyping based on the L1 sequence was done for HPV positive cases including temporally distinct tumors for four patients. Clinicopathologic data including progression free survival was also analyzed.

Results

All ISP and ISP-associated SNSCC demonstrated either an EGFR mutation or HPV infection. HPV and EGFR mutation were mutually exclusive in all cases of ISP-associated SNSCC and all but one ISP; this case was only weakly HPV positive, and analysis of a prior temporally distinct ISP specimen from this patient failed to show HPV infection, suggesting transient infection/incidental colonization. HPV subtypes in ISP and ISP-associated SNSCC were predominantly low-risk, in contrast with SNSCC without ISP association, which showed frequent high-risk HPV. All paired ISP and associated SNSCC samples demonstrated concordant HPV status and EGFR genotypes. ISP progression to SNSCC was significantly associated with the presence of HPV infection and the absence of an EGFR mutation (log-rank = 9.620, P = 0.002).

Conclusions

Collectively our data show that EGFR mutations and HPV infection represent essential, alternative oncogenic mechanisms in ISP and ISP-associated SNSCC.

Analysis of miRNA expression profiling identifies miR-214-3p as a novel biomarker in sinonasal inverted papilloma

Aim: To analyze the expression profile, diagnostic and clinicopathological significances of miRNAs in sinonasal inverted papilloma (SNIP). Materials & methods: The expression profile of miRNAs was analyzed using a miRNA microarray approach. The potential functions and clinical significances of specific miRNAs were further analyzed by bioinformatics and statistical methods. Results: The microarray assay identified 37 significantly upregulated and 21 downregulated miRNAs in SNIP. Of nine miRNAs randomly selected, the expression levels of seven miRNAs were confirmed by quantitative real-time PCR. The potential target genes of several candidate miRNAs were enriched in some biological processes and cellular signaling pathways related to tumorigenesis. Receiever operating characteristic curve analysis for miR-214-3p indicated an area under the curve of 0.932. Notably, its expression level was significantly decreased in SNIP tissues and associated with SNIP staging and recurrence. Conclusion: MiR-214-3p can possibly serve as a valuable biomarker and a therapeutic target for SNIP.

Role of the Akt/mTOR signaling pathway in human papillomavirus-associated nasal and sinonasal inverted papilloma

Nasal and sinonasal inverted papilloma (NSIP) is a benign tumor in which surface epithelial cells grow downward into the underlying supportive tissue with varying degrees of metaplasia. Human papillomavirus (HPV) has been proposed as the causal agent in the pathogenesis of this disease. Many studies have shown that HPV can activate the Akt/mechanistic target of rapamycin (mTOR) signaling pathway, but the role of this pathway in HPV-associated NSIP is largely unknown. In this study, we enrolled 40 control tissue samples and 80 NSIP tissue samples. HPV genotyping showed that 47 of the 80 examined cases of NSIP were HPV-positive (58.8%), and the most common subtype was HPV11 (20/53, 37.7%). The immunohistochemistry showed statistically significant differences in phosphorylated Akt and phosphorylated S6 ribosomal protein staining among control samples, HPV-positive NSIP and HPV-negative NSIP. The HPV11 L1-L2 plasmid increased the proliferation of normal human nasopharyngeal epithelial NP69-SV40T cells and human nasopharyngeal cancer CNE1 cells. Meanwhile, rapamycin, an mTOR inhibitor, reversed the increased cell proliferation induced by the HPV11 L1-L2 plasmid. Western blot analysis showed that Akt/mTOR/S6 were overexpressed in NP69-SV40T cells and CNE1 cells infected with the HPV11 L1-L2 plasmid. These data demonstrate that HPV promotes cell proliferation through the Akt/mTOR signaling pathway in NSIP.

Advances in recurrence and malignant transformation of sinonasal inverted papillomas

Sinonasal inverted papilloma (SIP) is a benign tumor of the nasal cavity and sinus. SIP is characterized by aggressive malignant transformation and a high rate of recurrence. Inadequate removal of the tumor during surgery is one of the most significant contributors to SIP recurrence. A growing body of evidence suggests that molecular alteration in SIP, including human papilloma virus infections, single nucleotide polymorphisms of key genes, deregulation of signaling pathways and immunological changes, may lead to SIP occurrence and malignant transformation. However, the extent to which these molecular mechanisms contribute to SIP pathology and transformation remains unclear due to limited research. Further studies are warranted to elucidate the primary dependent factors that contribute to SIP etiology. The present article reviewed risk factors of progression and recurrence of SIP, including outdoor and industrial occupational exposure, smoking, septal deviation, SIP location, recurrent cases, stage of SIP-associated squamous cell carcinoma and choice of surgical method.

Malignant transformation of sinonasal inverted papilloma and related genetic alterations: a systematic review

Schneiderian papillomas are uncommon tumors which may develop within the nasal cavity and comprise three well-defined histological types: sinonasal inverted papilloma (SNIP), exophytic papilloma, and oncocytic papilloma. It is well known the rate of Schneiderian papilloma may also present a malignant degeneration and SNIP represents the most important subgroup in consideration of its frequency and malignant propensity. Although HPV infection is always considered the first event favoring the development of SNIP, however, it is not established as an eventual connection between viral actions and malignant transformation. In fact, different molecular mechanisms are suspected to play a crucial role in this process and, currently, many authors agree that only by improving our knowledge about these mechanisms it will be possible to achieve new and effective targeted therapies. So the aim of this study was firstly to systematically review the literature focusing on different biomarkers that could be implicated in the stages of SNIP malignant degeneration. Secondly, a systematic review with meta-analysis was performed to better define the incidence of sinonasal malignancies originating from Schneiderian papilloma (SNIP, exophytic papilloma, and oncocytic papilloma). Twenty-nine studies comprising a total of 3177 patients were statistically analyzed. Results showed a 9% (95% CI = 7-11) overall rate of malignant transformation from Schneiderian papilloma. In conclusion, this analysis confirmed that the potential malignancy of Schneiderian papilloma should not be underestimated. On the other hand, our review showed the paucity of studies investigating the molecular alterations which may be related with the malignant transformation of SNIP.

Transcriptionally Active High-Risk Human Papillomavirus is Not a Common Etiologic Agent in the Malignant Transformation of Inverted Schneiderian Papillomas

The role of human papillomavirus (HPV) as an etiologic and transformational agent in inverted Schneiderian papilloma (ISP) is unclear. Indeed, reported detection rates of HPV in ISPs range from 0 to 100%. The true incidence has been confounded by a tendency to conflate high- and low-risk HPV types and by the inability to discern biologically relevant from irrelevant HPV infections. The recent development of RNA in situ hybridization for high-risk HPV E6/E7 mRNA now allows the direct visualization of transcriptionally active high-risk HPV in ISP, providing an opportunity to more definitively assess its role in the development and progression of ISPs. We performed p16 immunohistochemistry and high-risk HPV RNA in situ hybridization on 30 benign ISPs, 7 ISPs with dysplasia, 16 ISPs with carcinomatous transformation, and 7 non-keratinizing squamous cell carcinomas (SCCs) with inverted growth that were unassociated with ISP. Transcriptionally active HPV was not detected in any of the 52 ISPs including those that had undergone carcinomatous transformation, but it was detected in two of seven (29%) non-keratinizing SCCs that showed inverted growth. There was a strong correlation between high-risk HPV RNA in situ hybridization and p16 immunohistochemistry (97%; p < 0.01). These results indicate that transcriptionally active high-risk HPV does not play a common role in either the development of ISP or in its transformation into carcinoma.

Atypical presentations of sinonasal inverted papilloma: Surgical management and influence on the recurrence rate

BACKGROUND

Sinonasal inverted papilloma (SNIP), classically, is a unilateral benign tumor of the nasal lateral wall. Numerous variations have been observed, depending on location, bilateral presentation, or association with nasal polyposis.

OBJECTIVE

The aim of this work was to describe atypical presentations of SNIPs with their management specificities and to assess their influence on the recurrence rate in a large case series.

METHODS

A retrospective single center study of 110 patients treated for SNIP. Atypical inverted papillomas were identified according to the following criteria: (1) unusual location (frontal, posterior, anterior), (2) bilateral involvement, and (3) association with nasal polyposis. Surgical management was detailed, and the influence of each atypical group on recurrence was assessed by using Kaplan-Meier survival curves and the log-rank test.

RESULTS

Distribution of atypical presentations was as follows: frontal sinus localization (10.9%); posterior localization, including sphenoid sinus (9%); nasal anterior localization (3.6%); bilateral involvement (3.6%); and nasal polyposis association (10%). The surgical approach was endoscopic (74.5%), external (5.5%), or combined endoscopic and external (20%). Except for nasal anterior localization, all the groups were associated with a higher recurrence rate, without reaching statistical significance.

CONCLUSION

Recurrence rates for these atypical presentations arise from their specific surgical challenges. The choice of the surgical technique is guided by tumor location and extension, and by the surgeon's experience; the main objective is a complete resection. The endoscopic endonasal approach is the most frequent procedure.

Smoking, not human papilloma virus infection, is a risk factor for recurrence of sinonasal inverted papilloma

BACKGROUND

The recurrence rate of sinonasal inverted papillomas (SNIP) is 15-20%. However, few studies have investigated patient-dependent factors related to recurrence of SNIPs.

OBJECTIVE

To analyze risk factors, including human papilloma virus (HPV) infection and smoking, as well as other factors, for recurrence of SNIPs.

METHODS

Fifty-four patients who were diagnosed with SNIP and underwent surgery were enrolled: 39 men and 15 women, with the mean age of 54.0 years. Their mean follow-up was 40.6 months. Demographics and information about the history of smoking, previous surgery, tumor extent, follow-up, and recurrence were reviewed retrospectively. Those patients whose tumors were associated with malignant transformation were excluded in this study. HPV detection and genotyping in the tumor specimens were performed with the HPV DNA chip, a polymerase chain reaction-based DNA microarray system.

RESULTS

Seven patients (13.0%) had recurrence, with a mean time to recurrence of 39.8 months. Recurrence rates in T1, T2, T3, and T4 of the Krouse staging system were 0% (0/4), 8.3% (2/24), 17.4% (4/23), and 33.3% (1/3), respectively (p > 0.5). Eight patients (14.8%) were positive for HPV DNA. All of these patients belonged to the group without recurrence (p > 0.5). However, recurrence rates according to HPV DNA positivity were not statistically different (0% versus 15.2%). Three (42.9%) in the group with recurrence and four (8.5%) in the group without recurrence were smokers (p < 0.5).

CONCLUSION

Smoking was associated with recurrence of SNIP. However, HPV infection is not a recurrence of SNIP risk factor.

Etiology of sinonasal inverted papilloma: A narrative review

Objective

Sinonasal inverted papilloma (IP) is a benign and uncommon tumor of the nasal cavity and paranasal sinuses with a tendency for recurrence and even malignant transformation. Though the morphology and clinical behavior of this lesion has been well described, its etiology remains controversial.

Methods

Computerized searches were performed in PubMed, Scopus, and Google scholar through May 2015. In this review, etiologic factors including human papilloma virus (HPV), Epstein–Barr virus (EBV), cell cycle related proteins and angiogenic factors, occupational and environmental exposures, and chronic inflammation, will be discussed.

Results

Many studies indicate that HPV has been detected in a significant percentage of IP, while EBV has not been shown to be significantly associated. Certain cell cycle regulatory factors and angiogenic proteins contribute to the dysregulation of proliferation and apoptosis, and facilitate migration and tumor invasion. Occupational exposures, such as welding and organic solvents, have been implicated, and smoking seems more critical to recurrence and dysplasia rather than initial IP occurrence. Chronic inflammation may also have a causative relationship with inverted papilloma, but the mechanism is unclear.

Conclusions

Though etiology of sinonasal IP remains controversial, the studies reviewed here indicate a role for viral infection, cell cycle and angiogenic factors, environmental and occupational exposure, and chronic inflammation. Further study on etiologic factors is necessary for clinical guidance and therapeutic targets.