Human papilloma virus and p53 expression in carcinomas associated with sinonasal papillomas: a Danish Epidemiological study 1980-1998

High-risk HPV Does not Appear to be an Important Risk Factor for Sinonasal Carcinomas in Turkish Population: A Tertiary Center Experience

Background. The sinonasal tract is the second most common site of human papillomavirus (HPV)-related carcinomas in the head and neck. Published data on the association between sinonasal tumors and HPV are quite inconsistent among different regions. Material and methods. We performed high-risk HPV DNA in situ hybridization (ISH) and p16 immunohistochemistry on sinonasal carcinomas diagnosed between 2006 and 2016. Results. Of 105 sinonasal carcinomas, we found only two (2%) HPV-positive cases; both had non-keratinizing morphology and were diffusely positive for p16. By histologic type, HPV DNA positivity rate was 14% in non-keratinizing squamous cell carcinomas, and we did not detect HPV DNA in any other type of sinonasal carcinomas. Thirteen HPV-negative tumors (7 salivary gland carcinomas, 3 sinonasal undifferentiated carcinomas, 2 keratinizing squamous cell carcinomas, and 1 non-keratinizing squamous cell carcinoma) were positive for p16. In nine carcinomas arising from an underlying sinonasal papilloma, p16 and HPV DNA ISH were evaluated in both carcinoma and papilloma areas and all were negative. Follow-up information was available for 104 patients; 46 (44%) were alive and 58 (55%) died of disease. One of the two HPV-positive patients died of the disease; the other was alive at 100 months of follow-up. Conclusions. We detected a much lower percentage of HPV positivity in sinonasal carcinomas when compared to the literature. We believe that our results support various rates of HPV-related carcinomas depending on the geographic and ethnic characteristics.

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.

Impact of human papillomavirus in sinonasal cancer-a systematic review

BACKGROUND

Human papillomavirus (HPV) is an established prognostic marker in oropharyngeal squamous cell carcinoma. Currently, the role of HPV in sinonasal carcinoma is being explored.

OBJECTIVES

This systematic review addresses the role of HPV in sinonasal cancer, establishing the occurrence of HPV-positive cancers and the influence of HPV-positivity on prognosis in sinonasal cancer as well as the utility of the putative surrogate marker of HPV (p16) in sinonasal cancer.

MATERIAL AND METHODS

Studies were identified with searches of Medline via PubMed and Embase via OVID (4 May 2020). Articles on original research concerning sinonasal cancer and HPV in humans written in English were included. Case reports with less than five cases were excluded.

RESULTS

Initially, 545 articles were identified; 190 duplicate articles were removed leaving 355 articles for title/abstract screening. Title/abstract screening excluded 243 articles, leaving 112 studies assessed for eligibility. After full-text screening, 57 studies were included. All articles investigated the significance of HPV in sinonasal carcinomas. HPV was reported in approximately 30% of sinonasal squamous cell carcinoma (SNSCC), where it was associated with a better prognosis. In sinonasal cancer, p16 is associated with diagnostic pitfalls and a putative utility of p16 in SNSCC has yet to be established. HPV was not frequently reported in other types of sinonasal carcinomas, besides the recently described subtype, HPV-dependent Multiphenotypic Sinonasal Carcinoma. In other types of sinonasal carcinoma, HPV is not frequently found.

CONCLUSION

Approximately 30% of SNSCC are HPV-positive. HPV-positivity in SNSCC is associated with improved survival. HPV occurs only rarely in other sinonasal cancers. There is currently not sufficient evidence for p16 as a surrogate marker of HPV in SNSCC.

HPV-Associated Benign Squamous Cell Papillomas in the Upper Aero-Digestive Tract and Their Malignant Potential

Squamous cell papilloma (SCP) in the upper aero-digestive tract is a rare disease entity with bimodal age presentation both at childhood and in adults. It originates from stratified squamous and/or respiratory epithelium. Traditionally, SCPs have been linked to chemical or mechanical irritation but, since the 1980s, they have also been associated with human papillomavirus (HPV) infection. Approximately 30% of the head and neck SCPs are associated with HPV infection, with this association being highest for laryngeal papillomas (76–94%), followed by oral (27–48%), sinonasal (25–40%), and oropharyngeal papillomas (6–7%). There is, however, a wide variation in HPV prevalence, the highest being in esophageal SCPs (11–57%). HPV6 and HPV11 are the two main HPV genotypes present, but these are also high-risk HPVs as they are infrequently detected. Some 20% of the oral and oropharyngeal papillomas also contain cutaneous HPV genotypes. Despite their benign morphology, some SCPs tend to recur and even undergo malignant transformation. The highest malignant potential is associated with sinonasal inverted papillomas (7–11%). This review discusses the evidence regarding HPV etiology of benign SCPs in the upper aero-digestive tract and their HPV-related malignant transformation. In addition, studies on HPV exposure at an early age are discussed, as are the animal models shedding light on HPV transmission, viral latency, and its reactivation.

Sinonasal Squamous Cell Carcinoma, a Narrative Reappraisal of the Current Evidence

Simple Summary

Sinonasal squamous cell carcinomas are a group of diverse tumors affecting the nasal cavity and paranasal sinuses. As a direct consequence of their rarity and heterogeneity, diagnosis is challenging, and treatment does not follow universally accepted protocols. Though surgery represents the mainstay of treatment, neoadjuvant and adjuvant therapies have pivotal roles in improving outcomes of patients treated with curative intent. Indications to endoscopic surgery have been expanding over the last three decades, but a considerable number of patients affected by sinonasal squamous cell carcinoma still need open surgical procedures. Management of the neck in patients affected by sinonasal squamous cell carcinoma is controversial. Curative-intended treatment of recurrent and/or metastatic tumors, alongside palliation of uncurable cases, represent poorly explored aspects of this disease.

Abstract

Sinonasal squamous cell carcinoma is a rare tumor affecting the nasal cavity and paranasal sinuses. Several aspects of this disease, ranging from epidemiology to biology, pathology, diagnosis, staging, treatment, and post-treatment surveillance are controversial, and consensus on how to manage this sinonasal cancer is lacking. A narrative literature review was performed to summarize the current evidence and provide the reader with available data supporting the decision-making process in patients affected by sinonasal squamous cell carcinoma, alongside the authors’ personal opinion on the unsolved issues of this tumor. The review has highlighted several advances in molecular definition of epithelial cancers of the sinonasal tract. Surgery represents the pivot of treatment and is performed through an endoscopic transnasal approach whenever feasible. Open surgery is required for a large proportion of cases. Reconstruction of the defect follows principles of skull base and cranio-maxillo-facial reconstruction. Chemotherapy is given as neoadjuvant treatment or concomitantly to radiotherapy. Photon-based radiation therapy has a crucial role in the adjuvant setting. Particle therapy is providing promising results. Management of the neck should be planned based on the presence of clinically appreciable metastases, primary tumor extension, and need for recipient vessels. Biotherapy and immunotherapy are still underexplored therapeutical modalities.

Human Papillomavirus in Sinonasal Squamous Cell Carcinoma: A Systematic Review and Meta-Analysis

Simple Summary

The causative role of human papillomavirus (HPV) in sinonasal squamous cell carcinoma (SNSCC) remains unclear and is hindered by small studies using variable HPV detection techniques. This meta-analysis aims to provide an updated overview of HPV prevalence in SNSCC stratified by detection method, anatomic subsite, and geographic region. From 60 eligible studies, an overall HPV prevalence was estimated at 26%. When stratified by detection method, HPV prevalence was lower when using multiple substrate testing compared to single substrate testing. Anatomic subsite HPV prevalence was higher in subsites with high exposure to secretion flow compared to low exposure subsites. HPV prevalence in SNSCC followed the global distribution of HPV+ oropharyngeal squamous cell carcinoma. Taken together, this meta-analysis further supports a role for HPV in a subset of SNSCCs.

Abstract

Human papillomavirus (HPV) drives tumorigenesis in a subset of oropharyngeal squamous cell carcinomas (OPSCC) and is increasing in prevalence across the world. Mounting evidence suggests HPV is also involved in a subset of sinonasal squamous cell carcinomas (SNSCC), yet small sample sizes and variability of HPV detection techniques in existing literature hinder definitive conclusions. A systematic review was performed by searching literature through March 29th 2020 using PubMed, Embase, and Web of Science Core Collection databases. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed by two authors independently. A meta-analysis was performed using the random-effects model. Sixty studies (n = 1449) were eligible for statistical analysis estimating an overall HPV prevalence of 25.5% (95% CI 20.7–31.0). When stratified by HPV detection method, prevalence with multiple substrate testing (20.5%, 95% CI 14.5–28.2) was lower than with single substrate testing (31.7%, 95% CI 23.6–41.1), highest in high-exposure anatomic subsites (nasal cavity and ethmoids) (37.6%, 95% CI 26.5–50.2) vs. low-exposure (15.1%, 95% CI 7.3–28.6) and highest in high HPV+ OPSCC prevalence geographic regions (North America) (30.9%, 95% CI 21.9–41.5) vs. low (Africa) (13.1, 95% CI 6.5–24.5)). While small sample sizes and variability in data cloud firm conclusions, here, we provide a new reference point prevalence for HPV in SNSCC along with orthogonal data supporting a causative role for virally driven tumorigenesis, including that HPV is more commonly found in sinonasal subsites with increased exposure to refluxed oropharyngeal secretions and in geographic regions where HPV+ OPSCC is more prevalent.

Does evaluation of tumor volume or/both origination site better guide to optimal surgery for inverted papilloma?

INTRODUCTION

Sinonasal inverted papilloma is noted for its high rate of recurrence. Staging systems aid to reduce recurrence and avoid excessive surgeries by guiding the selection of the optimal surgical approach.

OBJECTIVE

To evaluate the effectiveness of different endoscopic approaches in inverted papilloma by assessing tumor origin site and tumor volume.

METHODS

Krouse classification system that is based on tumor volume was used for staging; furthermore, tumor origin sites were grouped as lateral nasal wall, medial wall and other walls of maxillary sinus. The main treatment method for all patients was endoscopic sinus surgery. Endoscopic extended middle meatal antrostomy, endoscopic Caldwell-Luc and endoscopic medial maxillectomy were the additional surgery types performed in different combinations.

RESULTS

Fifty-five patients (42 male) with a mean 54.9±14.4 years of age were included. 37 patients were diagnosed with advanced stage inverted papilloma (67.2 %). Recurrence was observed in 12 patients (21.8 %). In early stage lateral nasal wall origination, no recurrence was observed in the simple tumor resection group (0/10). In early stage medial wall origination, no recurrence was observed in the extended middle meatal antrostomy group (0/8). In advanced stage medial wall origination, the recurrence rates of extended middle meatal antrostomy, extended middle meatal antrostomy+endoscopic Caldwell- Luc and endoscopic medial maxillectomy were 100.0 %, 53.8 % and 13.6 %, respectively (p=0.002). In advanced stage other walls of maxillary sinus origination, recurrence rates of extended middle meatal antrostomy+endoscopic Caldwell-Luc and endoscopic medial maxillectomy were 20 % and 16.6 %, respectively (p=0.887).

CONCLUSION

Tumor origin site, tumor stage and surgery types show an impact on recurrence. Despite the fact that tumor origin site singly could lead to appropriate selection of the surgery type in most cases, tumor stage carries substantial importance in selection of surgery type for sinonasal-inverted papilloma. An operation plan regarding both tumor volume and tumor origin site may aid surgeons in selecting optimal endoscopic surgical method to avoid recurrence or excessive surgeries.

Inverted papilloma of the conjunctiva

Objective

The purpose of the present study is to describe the clinical and histopathological features of conjunctival inverted papilloma, to analyse for the presence of human papillomavirus (HPV), and to determine if HPV infection is associated with this type of tumour and its inverted growth pattern.

Methods and Analysis

Cases of conjunctival inverted papillomas were retrieved from the archives of the Department of Pathology, Rigshospitalet, Denmark. Patient records and pathology reports were reviewed. Formalin-fixed and paraffin-embedded tissue was analysed for the presence of HPV by immunohistochemistry, in situ hybridisation (ISH), PCR and HPV typed by sequencing.

Results

A total of four cases were retrieved. The age at diagnosis ranged from 41 to 77 years, with an equal sex distribution. All lesions were localised to the bulbar conjunctiva and two of the cases were pigmented. Histopathological examination did not reveal areas of dysplasia. All lesions were p16-positive and p53-positive by immunohistochemistry. High-risk HPV 58 was demonstrated in one lesion by ISH and PCR.

Conclusion

Here we present four cases of conjunctival inverted papilloma, which is an exceedingly rare tumour with only 11 previously reported cases in the literature. Both clinically and histopathologically, the tumours show distinct features compared with exophytic conjunctival papillomas. Furthermore, this is the first description of high-risk HPV 58 in a conjunctival tumour. The biological behaviour of the tumour is uncertain due to its rareness. However, a complete removal of the lesion and a careful observation are recommended. The finding of HPV 58 underlines the necessity of this precaution.

Sinonasal inverted papilloma associated with small cell neuroendocrine carcinoma: A case report and literature review of rare malignancies associated with inverted papilloma

We report a rare case of sinonasal inverted papilloma (IP) associated with small cell neuroendocrine carcinoma (SNEC). To our knowledge, this is the first report to describe SNEC found during the treatment of sinonasal IP. Surgery and five cycles of cisplatin plus etoposide with concurrent intensity modulated radiation therapy were performed. Neither local recurrence nor distant metastasis was noted during 6 years of post-diagnostic follow-up. The prognosis of SNEC is very poor. Treatment planning for sinonasal IP should consider a possible association with this rare but aggressive malignancy, whose treatment is completely different from that of squamous cell carcinoma, a malignancy which is commonly associated with IP. We also performed a PubMed review of the literature to identify the incidence and pathological diagnosis of associated malignancy. Among a total of 5286 cases of sinonasal IP (61 studies), the incidence of associated malignancy was 8.02% in squamous cell carcinoma, 0.19% in transitional cell carcinoma, 0.04% in mucoepidermoid carcinoma, 0.02% in verrucous cell carcinoma and 0.02% in adenocarcinoma. The incidence of associated malignancy was significantly higher in East and Southeast Asia (11.0%) and North America (10.4%) than in Europe (3.9%) (p=0.04 and p=0.03, respectively; T-test).

Comparison of Open versus Endoscopic Resection of Inverted Papilloma

Background

Lateral rhinotomy with medial maxillectomy has served as the standard for surgical management of inverted papilloma (IP) in the pre–endoscopic era; since the late 1980s, endoscopic techniques have emerged as the minimally invasive alternative. The objective of this study was twofold: (1) to compare operative parameters, complications, and recurrence rates and (2) predictive factors for recurrence for open versus endoscopic cases of IP resection.

Methods

Retrospective data analysis was performed on 68 patients with histopathologically confirmed IP treated at a tertiary care medical center from January 1983 to May 2005. Parameters for comparison included operative time (OT), estimated blood loss (EBL), length of hospital stay (HS), complications, and recurrence rate. Predictive factors for recurrence including open versus endoscopic cases, primary versus secondary IP, and tumor by Krouse stage were analyzed.

Results

The average age at time of presentation was 57.4 years with a male/female ratio of 2.2:1. Forty-nine patients underwent endoscopic resection, 13 patients underwent open resection, and 6 patients underwent limited open resection. Average OT and EBL were statistically similar for the three groups, whereas the average HS was statistically shorter (p = 0.002) for the endoscopic group. Biopsy-proven recurrence was noted in 11 (22%) endoscopic cases, 5 (39%) open cases, and 3 (50%) limited open cases. After reresection, all patients were free of disease. Mean follow-up was 16 months, 56 months, and 69 months for the endoscopic, open, and limited open groups, respectively. Analysis of predictive factors indicated that the surgical approach and primary versus secondary IP, regardless of approach, did not statistically impact recurrence rate. Chi-square analysis illustrated that patients with advanced-stage IP had a higher risk of recurrence (p = 0.002), regardless of surgical technique.

Conclusion

In this series, endoscopic resection of IP was associated with shorter HS and equivalent EBL and OT compared with the open groups. The overall recurrence rate was lower in the endoscopic group with acceptable morbidity compared with the open and limited open groups. Thus, the endoscopic approach may serve as a superior alternative to the open approaches for successful extirpation of IP.

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.

Low-Grade Papillary Schneiderian Carcinoma: A Case Report

The nasal cavity and paranasal sinuses are covered with ciliated respiratory mucosa of ectodermal origin, known as Schneiderian epithelium, which can give rise to different types of sinonasal carcinomas. A 42-year-old woman with a history of nasal polypectomy 3 years previously presented with nasal obstruction and rhinorrhea. She was found to have a papillary mass involving the left nasal cavity, and the left maxillary and ethmoidal sinuses by radiologic examination. She underwent endonasal resection under the diagnosis of oncocytic papilloma. The resected specimen showed exuberant invasive growth of papillary or inverted architectures of epithelial cells. The neoplastic cells were very bland, showing a round to polygonal shape, low nuclear-to-cytoplasmic ratio, abundant oncocytic cytoplasm, uniform nuclei, indistinct nucleoli, and scarce mitosis. The overall features were identical to those of a recent report of a low-grade papillary Schneiderian carcinoma. The main differential diagnosis is Schneiderian papilloma, and awareness of this novel entity is important for its proper treatment.

Combined endonasal and eyelid approach for management of extensive frontal sinus inverting papilloma

OBJECTIVES

Sinonasal inverting papilloma (IP) is a benign but locally aggressive mucosal neoplasm with a high recurrence rate. Extension into the frontal sinus presents surgical challenges for endonasal resection. This study presents an orbitofrontal approach for managing extensive IP.

STUDY DESIGN

Case series.

METHODS

Four patients seen between 2012 and 2016 with biopsy-proven IP with lateral frontal sinus extension underwent a combined endonasal and transpalpebral approach for tumor resection. Patient demographic data, preoperative characteristics, imaging, and follow-up data were compiled through retrospective chart review. Patients were selected for this approach when the tumor extended to the posterior frontal sinus wall, lateral frontal sinus recess, and orbit. Tumors were first approached endonasally until the frontal recess was reached. A Draf IIB or Draf III procedure was then performed to gain better exposure. Orbitofrontal exposure was achieved through an upper eyelid incision. Miniorbitofrontal craniotomy window was designed based on tumor location. Resection of the frontal and orbital extension was enhanced by endoscopic-assisted dissection through the orbitofrontal window.

RESULTS

The transpalpebral approach provided access to all walls of the ipsilateral frontal sinus, the intersinus septum, and the medial aspect of the contralateral sinus. Complete tumor resection was achieved in all patients. There were no orbital complications, no visible eyelid asymmetry or scarring, and all patients had preserved forehead sensation. There were no recurrences on follow-up.

CONCLUSION

Combining a transpalpebral orbitofrontal craniotomy with the endonasal approach allows complete resection of invasive IP with extension into the frontal sinus. This is achieved with great cosmetic results.

LEVEL OF EVIDENCE

4. Laryngoscope, 128:3-9, 2018.

OSPs and ESPs and ISPs, Oh My! An Update on Sinonasal (Schneiderian) Papillomas

Sinonasal (Schneiderian) papillomas are benign neoplasms that arise in the sinonasal tract. Since their initial descriptions, sinonasal papillomas have triggered debate regarding their classification, etiology, rate or predictors of malignant transformation, and other issues. While significant strides have been made in recent years, there are still aspects of sinonasal papillomas that remain unclear even now. This review will serve to update the practicing pathologist on the current understanding of sinonasal papillomas.

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.

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.

Rate of recurrence and malignant transformation in 88 cases with inverted papilloma between 1998-2008

Conclusions The recurrence rate of IP in the current study is comparable to international and national studies. When the primary tumour was located in the frontal or the sphenoid sinus, the tumour seemed more likely to recur. Some recurrences were more than 2 years after primary surgery, suggesting continued need for long-term follow-up. The rate of malignant transformation in inverted papilloma cases has not changed in Denmark. Objectives Inverted papillomas are benign tumours located in the nasal cavity and paranasal sinuses. They are known for their tendency to recur after surgery and show invasive growth, causing bone remodulation and the association with malignant transformation. The introduction of endoscopic sinus surgery and computer aided sinus surgery over the last decades has made this tumour more approachable with less cosmetic and functional damage. The objective of this study is to establish whether the recurrence rate and the rate of malignant transformation of IP have changed with the application of these new techniques. Method A retrospective study between 1998-2008 including 88 cases with inverted papilloma. Results In total, 25.3% had recurrence. Combined surgical approach with endoscope/open approach had the lowest rate of recurrence. A malignant transformation in the postoperative histological examination was found in 8.9%.

[Diagnostics of neoplasms of the nasal cavity and paranasal sinuses]

The objective of the present work was to address earlier diagnostics of benign and malignant tumours in the nasal cavity and paranasal sinuses with a view to its improvemen. The immunohistochemical study and the analysis of its results made possible not only differential diagnostics of the tumorigenic processes in the nasal cavity and paranasal sinuses but also the estimation of the qualitative potential of each neoplasm. The immunohistochemical study demonstrated that the development of cancer of the nasal cavity and paranasal sinuses was associated with a substantial increase in the proliferative activity of epithelium and the appearance of a large amount of the mutant P53 protein in the atypical cells. The cells of inverted papilloma and unaffected epithelium exhibited only weak proliferative activity, contained cytokeratin-8 in their cytoplasm, and did not express a pathological receptor protein at the cytoplasmic membrane surface.

Transcriptional activity of HPV in inverted papilloma demonstrated by in situ hybridization for E6/E7 mRNA

OBJECTIVE

Assess human papilloma virus (HPV) transcriptional activity in inverted Schneiderian papillomas (IPs).

STUDY DESIGN

Case series with chart review.

SETTING

Academic tertiary care center.

SUBJECTS AND METHODS

Retrospective clinicopathologic review of 19 cases of IP in patients undergoing surgical excision from 1995 to 2013 at Mayo Clinic in Rochester, Minnesota. Surgical pathology archival material was histopathologically reviewed using hematoxylin and eosin-stained slides. Formalin-fixed, paraffin-embedded material from each case was evaluated for p16 expression using immunohistochemistry as well as HPV DNA and E6/E7 messenger RNA (mRNA) transcription using polymerase chain reaction (PCR) and in situ hybridization (via RNAscope technology), respectively.

RESULTS

Eight patients were female (42%), with an average age of 53 years (range, 23-82 years). Three demonstrated malignancy, and 5 subsequently recurred. Average follow-up was 49 months (range, 0-200 months), and 1 patient died from squamous cell carcinoma arising from the IP. RNAscope detected HPV mRNA transcripts exclusively within IP in 100% of cases; however, in 11 patients (58%), less than 1% of cells exhibited transcriptional activity. Only 2 of 19 cases (11%) demonstrated mRNA activity in 50% or more cells. HPV DNA was detected in only 2 specimens by PCR.

CONCLUSIONS

This study reveals wide prevalence but limited transcriptional activity of HPV in IP. No correlation between HPV transcriptional activity and progression, recurrence, or malignant transformation was identified. These data suggest that transcription of HPV may contribute to the pathogenesis of IP, but prospective data are needed to definitively demonstrate this connection. These results also suggest that RNAscope may be more sensitive than PCR in detecting HPV activity in IP.

Inverted papilloma involving the temporal bone and its association with squamous cell carcinoma: critical analysis of the literature

Inverted papilloma is a rare, benign neoplasm, which usually originates from the lateral nasal wall and can be locally aggressive, extending into surrounding structures. Unusually, this disease involves temporal bone. There have been only 18 reported cases in the literature. The available data regarding inverted papilloma of the temporal bone are reviewed, and its etiopathogenesis, recurrence rate and association with squamous cell carcinoma are discussed.

14-3-3 gene expression exerts isoform-dependent functions in sinonasal pathophysiology

The expression profiles of 14-3-3β and θ isoforms, known to exert both oncogenic and antiapoptotic effects, were assessed in different entities of nasal pathophysiology. Flow cytometry and immunohistochemistry were used on paraffin-embedded sections of 51 inverted papillomas (IP), 26 nasal polyps (NP), 9 polyps with IP (NPIP) and 10 specimens of normal epithelium (NE). 14-3-3β expression was significantly upregulated in IP as compared with both NP (p=0.015) and NE (p=0.002). 14-3-3β was also increased in NPIP as compared with NE (p=0.008). 14-3-3β cytoplasmic staining was more pronounced in basal cells of the respiratory epithelium although serous glands and the vascular system were often positive as well. High 14-3-3β immunopositivity in IP patients concurred with increased proliferative activity shown by PCNA immunostaining (p=0.04). Expression of 14-3-3θ was also found increased in IP and NPIP patients, compared to NP (p=0.005, p=0.002 respectively) and NE (p=0.004 and p=0.001 respectively). 14-3-3θ cytoplasmic immunopositivity was detected in columnar epithelium, particularly in basal and subluminal cells, whereas no immunoreactivity was observed in NP and NE. Our results demonstrate differential expression of 14-3-3β and θ isoforms in sinonasal pathophysiology, supporting their implication, respectively, in the proliferative and inflammatory process engaged in the formation of IP.

Transitional neoplasms of the naso-lacrimal system: A review of the histopathology and histogenesis

Transitional papilloma (inverted papilloma, Schneiderian papilloma) is a relatively common, benign epithelial neoplasm of the sinonasal tract that also occurs in the lacrimal drainage system. The name transitional papilloma is recommended because it reflects the key histological features required for pathological diagnosis, as well as the histogenesis of the tumour. The histogenesis of the tumour is reviewed, together with its natural history, which is characterized by bone remodelling and destruction, a tendency to recur and to undergo malignant transformation. Biomarkers associated with these features have been identified in the sinonasal tumours and may also be of relevance to the lacrimal sac tumours, although the necessary studies have not yet been undertaken.

Human papillomavirus-related carcinomas of the sinonasal tract

High-risk human papillomavirus (HPV) is an established cause of head and neck carcinomas arising in the oropharynx. The presence of HPV has also been reported in some carcinomas arising in the sinonasal tract, but little is known about their overall incidence or their clinicopathologic profile. The surgical pathology archives of The Johns Hopkins Hospital were searched for all carcinomas arising in the sinonasal tract from 1995 to 2011, and tissue microarrays were constructed. p16 immunohistochemical analysis and DNA in situ hybridization for high-risk types of HPV were performed. Demographic and clinical outcome data were extracted from patient medical records. Of 161 sinonasal carcinomas, 34 (21%) were positive for high-risk HPV DNA, including type 16 (82%), type 31/33 (12%), and type 18 (6%). HPV-positive carcinomas consisted of 28 squamous cell carcinomas and variants (15 nonkeratinizing or partially keratinizing, 4 papillary, 5 adenosquamous, 4 basaloid), 1 small cell carcinoma, 1 sinonasal undifferentiated carcinoma, and 4 carcinomas that were difficult to classify but exhibited adenoid cystic carcinoma-like features. Immunohistochemistry for p16 was positive in 59/161 (37%) cases, and p16 expression strongly correlated with the presence of HPV DNA: 33 of 34 (97%) HPV-positive tumors exhibited high p16 expression, whereas only 26 of 127 (20%) HPV-negative tumors were p16 positive (P<0.0001). The HPV-related carcinomas occurred in 19 men and 15 women ranging in age from 33 to 87 years (mean, 54 y). A trend toward improved survival was observed in the HPV-positive group (hazard ratio=0.58, 95% confidence interval [0.26, 1.28]). The presence of high-risk HPV in 21% of sinonasal carcinomas confirms HPV as an important oncologic agent of carcinomas arising in the sinonasal tract. Although nonkeratinizing squamous cell carcinoma is the most common histologic type, there is a wide morphologic spectrum of HPV-related disease that includes a variant that resembles adenoid cystic carcinoma. The distinctiveness of these HPV-related carcinomas of the sinonasal tract with respect to risk factors, clinical behavior, and response to therapy remains to be clarified.

Skull base inverted papilloma: a comprehensive review

Skull base inverted papilloma (IP) is an unusual entity for many neurosurgeons. IP is renowned for its high rate of recurrence, its ability to cause local destruction, and its association with malignancy. This paper is a comprehensive review of the reports, studies, and reviews published in the current biomedical literature from 1947 to September 2010 and synthesize this information to focus on its potential invasion to the base of the skull and possible intradural extension. The objective is to familiarize the clinician with the different aspects of this unusual disease. The role of modern diagnostic tools in medical imaging in order to assess clearly the limits of the tumors and to enhance the efficiency and the safety in the choice of a surgical approach is pointed out. The treatment guidelines for IP have undergone a complex evolution that continues today. Radical excision of the tumour is technically difficult and often incomplete. Successful management of IP requires resection of the affected mucosa which could be achieved with open surgery, endoscopic, or combined approach. Radio and chemotherapy were used for certain indications. More optimally research would be a multicenter randomized trials with large size cohorts.

Detection of human papillomavirus in sinonasal carcinoma: systematic review and meta-analysis

Since first suggested (in 1983), the etiological role for human papillomavirus (HPV) in sinonasal carcinomas has been subject to constantly increasing interest. To perform systematic review and formal meta-analysis of the literature reporting on HPV detection in sinonasal squamous cell carcinomas (SCC), literature was searched through May 2012. The effect size was calculated as event rates (95% CI), with homogeneity testing using Cochran Q and I(2) statistics. Meta-regression was used to test the impact of study-level covariates (HPV detection method, geographic origin, papilloma type) on effect size, and potential publication bias was estimated using funnel plot symmetry. Thirty-five studies were eligible, covering 492 sinonasal SCCs from different geographic regions. Altogether, 133 (27.0%) cases tested HPV-positive; effect size 0.305 (95% CI, 0.260-0.355; fixed effects model), and 0.330 (95% CI, 0.249-0.423; random effects model. In meta-analysis stratified by (i) HPV detection technique and (ii) geographic study origin, the between-study heterogeneity was significant only for the latter; P = .526, and P = .0001, respectively. In maximum likelihood meta-regression, HPV detection method (P = .511) and geographic origin of the study (P = .812) were not significant study-level covariates. Some evidence for publication bias was found only among polymerase chain reaction-based studies and among studies from Europe and North America but with negligible effect on summary effect size estimates. In sensitivity analysis, all meta-analytic results were robust to all one-by-one study removals. In formal meta-regression, the variability in HPV detection rates reported in sinonasal SCCs was not explained by the HPV detection method or geographic origin of the study.

Detection of human papillomavirus in sinonasal papillomas: systematic review and meta-analysis

OBJECTIVES/HYPOTHESIS

To perform a systematic review and formal meta-analysis of the literature reporting on HPV detection in sinonasal papillomas. Since first reported in 1983, the etiological role for human papillomavirus (HPV) in sinonasal papillomas has been subject to increasing interest.

STUDY DESIGN

A systematic review, with meta-analysis and formal meta-regression.

METHODS

Literature was searched through April 2012. The effect size was calculated as event rates (95% confidence interval [CI]), with homogeneity testing using Cochran's Q and I(2) statistics. Meta-regression was used to test the impact of study-level covariates (HPV detection method, geographic origin, papilloma type) on effect size, and potential publication bias was estimated using funnel plot symmetry.

RESULTS

Seventy-six studies were eligible covering 1,956 sinonasal papillomas from different geographic regions. Altogether, 760 (38.8%) cases tested HPV-positive; effect size 0.421 (95% CI 0.359-0.485, random effects model). The summary HPV prevalence was highest (65.3%) in exophytic papillomas (EP), followed by inverted papillomas (37.8%) and cylindrical cell papillomas (22.5%). In meta-analysis stratified by 1) HPV detection technique, 2) geographic study origin, and 3) papilloma type, the between-study heterogeneity was significant only for the papilloma types (P = .001). In meta-regression, HPV detection method (P = .102), geographic origin (P = .149), or histological type (P = .240) were not significant study-level covariates. Some evidence for publication bias was found only for studies on EP. In sensitivity analysis, all meta-analytic results were robust to all one-by-one study removals.

CONCLUSIONS

Variability in HPV detection rates in sinonasal papillomas is explained by their histological types (not by HPV detection method or geographic origin of study), but none of the three were significant study-level covariates in formal meta-regression.

Prevalence of human papillomavirus, Epstein-Barr virus, p21, and p53 expression in sinonasal inverted papilloma, nasal polyp, and hypertrophied turbinate in Hong Kong patients

BACKGROUND

The purpose of this study of human papillomavirus (HPV), Epstein-Barr virus (EBV), p21, and p53 in sinonasal inverted papilloma (IP) was to help elucidate its pathogenesis.

METHODS

Seventy-three IPs, 48 nasal polyps, and 85 hypertrophied turbinates were subjected to HPV polymerase chain reaction (PCR) study. Seventy-three IPs, 30 nasal polyps, and 32 hypertrophied turbinates were subjected to EBV in situ hybridization (ISH), p21, and p53 immunohistochemical (IHC) studies.

RESULTS

HPV was positive in 3 of 73 IPs (4.1%). All specimens were EBV negative. In all, 99% of IPs showed strong and diffuse p21 nuclear reactivity. Most nasal polyps and hypertrophied turbinates showed weak to moderate immunoreactivity of the basal and parabasal cells. Only focal p53 immunoreactivity of the basal and parabasal cells was found in 19% of IPs and 40% of nasal polyps.

CONCLUSIONS

HPV prevalence of our IP is low. EBV is not present in IP. High p21 and low p53 expression in IP suggests a non-p53-dependent regulation pathway.

Sinonasal inverted papilloma: narrative review

BACKGROUND

Sinonasal inverted papilloma is a benign condition with the potential for recurrence and malignant change. Over the past few decades, numerous studies and reviews have addressed different aspects of this condition.

OBJECTIVE

To amalgamate the current literature on inverted papilloma, in order to review the evidence and consider the gaps in current knowledge.

METHODS

Retrospective, narrative review.

RESULTS

The reported incidence of inverted papilloma varies between centres and is affected by selection bias. The exact aetiology of inverted papilloma is not fully understood. Currently, there is no reliable histological or biological marker to predict the probability of recurrence or malignant transformation. There is no universally accepted staging system available for sinonasal inverted papilloma. Complete surgical removal of the tumour is the mainstay of treatment, but the method of choice depends on the extent of the disease, the skill of the surgeon and the technology available.

CONCLUSION

In order to compare different studies and to enable meta-analysis of the literature, there should be a universally accepted staging and classification system for sinonasal inverted papilloma. Further research on the aetiology of sinonasal inverted papilloma, and on biological markers for its recurrence and malignant transformation, is required. To enable meaningful future research, we would encourage multicentre participation with a consensus on management.

Expression of p53, p16INK4A, pRb, p21WAF1/CIP1, p27KIP1, cyclin D1, Ki-67 and HPV DNA in sinonasal endophytic Schneiderian (inverted) papilloma

CONCLUSIONS

Human papilloma virus (HPV) was associated with sinonasal inverted papilloma (SIP) in 14/20 (70%) patients with a prevalence of HPV 6/11; alterations of the cell cycle proteins were statistically significant.

OBJECTIVES

We investigated SIPs relationships between HPV infection and aberrant expression of cell cycle proteins.

MATERIALS AND METHODS

Twenty SIPs were evaluated for p53, p16(INK4a), pRb, p21(WAF1), p27(Kip1), cyclin D1 and Ki-67 expression by immunohistochemistry. HPV was investigated by polymerase chain reaction (PCR).

RESULTS

HPV DNA was detected in 14/20 patients with inverted papillomas (IPs) (70%). The majority of tumours showed strong p16, p21, p27, pRb and cyclin D1 staining and little or no p53 expression. Tumours harbouring dysplasia were significantly more likely to be p53-positive and exhibit up-regulated p21 and p27, and showed altered intensity and distribution of reactive cells into and through the epithelium. Dysplastic epithelium was strongly reactive for p16 and the MIB 1 labelling index was almost 20%. These findings were associated with expression of p53 in the same zones. Comparing the p53 reactivity with the presence of HPV DNA, SIPs were stratified as follows: HPV + p53-, 12 (63.15%); HPV + p53+, 2 (10.52%); HPV - p53+, 3 (15.78%) and HPV - p53-, 2 (10.52%). Statistical analysis showed that HPV presence correlated with p53-positive immunostaining (p=0.045).

The role of the human papillomavirus in the pathogenesis of Schneiderian inverted papillomas: an analytic overview of the evidence

BACKGROUND

Evidence of an etiological role for human papillomavirus (HPV) in Schneiderian inverted papillomas IP arose in the late 1980's; yet almost three decades later, the association between HPV and IP has yet to be universally accepted. This is probably due to the disparate HPV detection rates in IP reported in the literature. We analyzed the weight of published data in order to address the following questions: why do the HPV detection rates in IP vary so greatly? What is the relationship between low-risk (LR) and high-risk (HR) HPV types and HPV detection rates in IP? Is there a relationship between the presence and type of HPV in IP and recurrence and malignant progression?

MATERIALS AND METHODS

A search using the Pubmed search engine was performed to identify studies published in English from 01/87 through 12/06 using the MeSH terms ''HPV'' and ''Inverted", "Exophytic", "Oncocytic Schneiderian" or "Fungiform papilloma''. Data was abstracted from publications including histology, HPV target, HPV type, method of detection, etc. HPV results were stratified by histology and other variables. Tests for heterogeneity (between-study variability) were conducted, and weighted prevalence (WP) estimates and 95% confidence intervals (CI) were calculated using a random-effects inverse-variance model stratified on study. The association between HPV IP recurrence was estimated by random-effects inverse-variance weighted odds ratio (OR).

RESULTS

Weighted estimates revealed similar detection rates across detection methods, 26.8% (95%CI 16.4-37.2%) by ISH, 25.2% (95%CI 14.7-35.6%) by consensus PCR, and 23.6% (95%CI 12.2-35.0%) by type-specific PCR. A preponderance of HPV 6/11 is found in IP as compared to HPV 16/18; the overall unadjusted ratio of LR to high-risk HR HPV types is 2.8:1 The HPV detection rates significantly increase (Wald t-test P < 0.02) in IPs with high-grade dysplasia (WP 55.8%, 95%CI 30.5-81.0%) and carcinoma (WP 55.1%, 95%CI 37.0-73.2%) as compared to IPs with no dysplasia or mild dysplasia (WP 22.3%, 95%CI 15.9-28.6%). Furthermore, the preponderance of LR HPV in benign IP (ratio LR/HR = 4.8:1) shifts in dysplastic and malignant IP. The LR/HR ratio is 1.1:1 for IPs with high-grade dysplasias, this ratio is inverted to favor HR HPV (1:2.4) for malignant IP. Recurrences developed in 44 of 236 patients; HPV was detected in 27 of 44 IPs (WP 57.9%, 95%CI 31.6-84.2%) that developed recurrences and in 24 of 192 IPs (WP 9.7%, 95%CI 4.4-15.0%) that did not develop recurrence. The presence of HPV was significantly associated with the likelihood of developing recurrence (weighted OR of 10.2, 95%CI 3.2-32.8).

CONCLUSIONS

We hypothesize that LR HPV may induce IP formation, and then are lost as infected cells are shed, as a "hit and run" phenomenon. HPV detection rates increase in dysplastic IP and SCC-ex-IP with increasing ratio of HR to LR HPV types, compared to nondysplastic IP. We believe that one explanation for the variation in HPV detection rates between different studies may be the actual histologic composition of the cohort. That is, if one series contains a higher frequency of dysplastic and malignant IP, it may have a higher detection rate than another series which contains only nondysplastic IP. We hypothesize that the higher rates of HPV detection in dysplastic and malignant IP may be related to HPV integration. The implication of this is that HPV sub-type testing may identify patients at risk for recurrence, or progression to dysplasia and malignancy, and thus may impact surveillance protocols.

Epigenetic events underlie the pathogenesis of sinonasal papillomas

Benign inverted papillomas have been reported as monoclonal but lacking common genetic alterations identified in squamous cell carcinoma of the head and neck. Epigenetic changes alter the heritable state of gene expression and chromatin organization without change in DNA sequence. We investigated whether epigenetic events of aberrant promoter hypermethylation in genes known to be involved in squamous head and neck cancer underlie the pathogenesis of sinonasal papillomas. Ten formalin-fixed paraffin DNA samples from three inverted papilloma cases, two exophytic (everted) papilloma cases, and two cases with inverted and exophytic components were studied. DNA was obtained from microdissected areas of normal and papilloma areas and examined using a panel of 41 gene probes, designed to interrogate 35 unique genes for aberrant methylation status (22 genes) using the methylation-specific multiplex-ligation-specific polymerase assay. Methylation-specific PCR was employed to confirm aberrant methylation detected by the methylation-specific multiplex-ligation-specific polymerase assay. All seven cases indicated at least one epigenetic event of aberrant promoter hypermethylation. The CDKN2B gene was a consistent target of aberrant methylation in six of seven cases. Methylation-specific PCR confirmed hypermethylation of CDKN2B. Recurrent biopsies from two inverted papilloma cases had common epigenetic events. Promoter hypermethylation of CDKN2B was a consistent epigenetic event. Common epigenetic alterations in recurrent biopsies underscore a monoclonal origin for these lesions. Epigenetic events contribute to the underlying pathogenesis of benign inverted and exophytic papillomas. As a consistent target of aberrant promoter hypermethylation, CDKN2B may serve as an important epigenetic biomarker for gene reactivation studies.

Clinical and pathological analysis of recurrent inverted papilloma

OBJECTIVES

We analyzed the clinical characteristics, pathological findings, and treatment outcomes of patients with recurrent sinonasal inverted papilloma (IP).

METHODS

This retrospective study consisted of 13 patients with recurrent IP. Patient data were collected on prior treatment, sites of recurrence, surgical procedures, pathological findings, and postoperative time to recurrence.

RESULTS

Eleven of the 13 patients (85%) had recurrence in the ethmoid sinus, particularly at the lamina papyracea (n = 8; 62%). Inverted papilloma with severe dysplasia (SD) was observed in 4 patients, 3 of whom showed malignant transformation of the recurrent tumor. Craniofacial resection was performed in 2 of the 4 patients, resulting in no further recurrence. However, the tumor was not managed in the remaining 2 patients. In the 9 patients without SD, lateral rhinotomy was performed in 6 patients and endoscopic sinus surgery was selected in 3 patients who had a small tumor without scar formation. No further recurrence was observed in the 9 patients.

CONCLUSIONS

Careful management of IP around the lamina papyracea is essential during initial surgery. Recurrent IP without SD can be successfully managed by lateral rhinotomy in most cases, and by endoscopic sinus surgery in selected cases. However, more aggressive treatment, including craniofacial resection, should be considered in IP with SD, which is associated with a high rate of recurrence and malignant transformation.

Risks of malignancy in inverted papilloma of the nose and paranasal sinuses

PURPOSE OF REVIEW

The majority of inverted nasal papilloma are benign and treatment is by complete local surgical removal. There is an associated real, but small risk of malignancy, which may coexist at the time of presentation or develop at a later time. This article reviews some of the recent publications addressing the association of inverted papilloma with malignancy.

RECENT FINDINGS

Neither the etiology of inverted papilloma nor the factors responsible for malignant transformation are fully elucidated to date. Inverted papilloma is associated with squamous cell carcinoma in approximately 10% of the cases. Malignancy may occur synchronously or metachronously.

SUMMARY

Based on the literature, the rates of synchronous and metachronous carcinoma are 7.1 and 3.6%, respectively, although rates may be exaggerated due to a referral bias to tertiary centres. A thorough removal of all diseased mucosa is curative and a meticulous histological examination of the entire specimen is necessary. The working risk is approximately 10%. Recurrent disease and metachronous carcinoma can develop after a prolonged period of time. As most recurrences are due to incomplete resection, it is mandatory to perform a close follow-up, with biopsies performed when indicated. Life-long follow-up is recommended.

Human papillomavirus: cause of epithelial lacrimal sac neoplasia?

PURPOSE

Epithelial tumours of the lacrimal sac are rare but important entities that may carry grave prognoses. In this study the prevalence and possible role of human papillomavirus (HPV) infection in epithelial tumours of the lacrimal sac were evaluated.

METHODS

Five papillomas and six carcinomas of the lacrimal sac were investigated for the presence of HPV using the polymerase chain reaction (PCR) technique. Fifteen specimens of dacryocystitis were included in the PCR reactions as controls. Furthermore, DNA in situ hybridization (ISH) and RNA ISH were performed.

RESULTS

Low-risk HPV types 6 or 11 were identified in all four lacrimal sac papillomas suitable for PCR analysis and in situ hybridization. Four of six lacrimal sac carcinomas harboured HPV. One carcinoma was positive for HPV 11 only, two carcinomas had concomitant infection with HPV 6 or 11 and high-risk HPV 16, and the remaining carcinoma was positive for HPV 16. All specimens of dacryocystitis were betaglobin-positive and HPV-negative. Using DNA ISH, two papillomas and a single carcinoma showed evidence for vegetative HPV 11 DNA replication, whereas no HPV 16 DNA replication was found in the five carcinomas tested. HPV 11 RNA was demonstrated in two papillomas.

CONCLUSIONS

By analysing 11 epithelial lacrimal sac papillomas and carcinomas using PCR, DNA ISH and RNA ISH, we found HPV DNA in all investigated transitional epithelium tumours of the lacrimal sac. HPV RNA was present in two of eight epithelial lacrimal sac tumours positive for HPV DNA. As RNA degrades fast in paraffin-embedded tissue, only a small fraction of DNA-positive tumours can be expected to be RNA-positive. We therefore suggest that HPV infection is associated with the development of lacrimal sac papillomas and carcinomas.

Do nasal polyps and inverted papilloma have similar disorders in cell cycle regulation?

BACKGROUND

The aim of this study was to determine the expression of cell cycle regulation genes in patients with inverted papilloma (IP) and compare this with expression in patients with nasal polyps (NPs).

METHODS

Tissue from 18 patients with IP and 5 patients with NPs were stained by immunohistochemistry techniques for p53 and p27. Measurement of the gene expression was performed by three assessors, who we blinded with respect to the specimens.

RESULTS

The mean score for p53 expression (3.33) was significantly higher in the IP group than the NP group (1.46). The mean difference between IP and NPs was 1.80 (CI, 1.15-2.46; p = 0.003). Additionally, we showed in a number of individuals variation in the p53 expression within the same specimen. There was no difference in the mean scores for p27, with the mean difference 0.79 (CI, 0.30-1.89; p = 0.147).

CONCLUSION

Our study established a significantly increased expression of p53 in IP when compared with NPs. Additionally, there appear to be two different cell populations identified within the same specimens, which exhibited variation in their p53 expression.

Inverted papilloma of paranasal sinuses

INTRODUCTION

Inverted papilloma (Schneiderian papilloma) is a primarily benign lesion that occurs in the nasal cavity and paranasal sinuses. Clinical problems include a tendency towards local destruction, recurrence and malignant transformation into squamous cell carcinoma. Hence, complete surgical removal is the therapy of choice and a meticulous follow-up is mandatory.

STUDY DESIGN

This is a review including a short introduction to the different histological types of nasal papilloma, their pathogenesis and the clinical and histopathological diagnosis. Staging systems, therapeutic approaches, and surgical concepts are discussed.

RESULT

The detection and definition of factors that allow a prognosis of recurrence or malignant transformation of inverted papilloma is an active field of research. The results of studies dealing with the definition of prognostic factors, that investigated immunohistochemical methods, virus detection, molecular genetics, and histomorphological studies are discussed including our own results on the prognostic value of histology. A concept for the diagnosis, management, therapy and follow-up of inverted papilloma is proposed.

Prevalence of high-risk human papillomavirus DNA in nonkeratinizing (cylindrical cell) carcinoma of the sinonasal tract: a distinct clinicopathologic and molecular disease entity

Carcinomas of the nose and paranasal sinuses are a heterogeneous group of neoplasms that differ histologically, biologically, and clinically. Some of these tumors are known to harbor high-risk human papillomavirus (HPV) DNA. In an attempt to identify specific phenotypes associated with HPV infection, 39 cases of sinonasal carcinomas were evaluated by PCR for the presence of HPV DNA. The tumors were also studied with a panel of immunohistochemical stains, including p16, p53, and Ki-67 antibodies. Twenty-one cases were identified as keratinizing squamous cell carcinoma (KSCC) with a male-to-female ratio of 3:1. Eight cases were nonkeratinizing (cylindrical cell) carcinoma (NKCa) with a male-to-female ratio of 1:1. Ten cases were sinonasal undifferentiated carcinoma (SNUC), and 9 of these patients were men. HPV DNA, particularly type 16, was detected in 9 cases: 4 of 21 (19%) of KSCC, 4 of 8 (50%) of NKCa, and 1 of 10 (10%) of SNUC. In addition to a higher prevalence of HPV DNA in NKCa, the tumors also showed a distinct immunophenotype characterized by strong and diffuse staining for p16, high labeling scores for Ki-67, and negative or low reactivity to p53. On the other hand, KSCC and SNUC were either negative or weakly reactive to p16 antibodies. KSCC cases were more likely to be positive and more strongly reactive to p53 stain. Unlike KSCC, SNUC had high Ki-67 labeling scores. These observations suggest that NKCa of the sinonasal tract is a distinct histopathologic and molecular disease entity, which should be added to the list of upper aerodigestive tract tumors with strong etiologic relationship to high risk HPV.

Human papillomavirus (HPV) transcripts in malignant inverted papilloma are from integrated HPV DNA

OBJECTIVES

The objectives of the study were to detect human papillomavirus (HPV) sequences in nasal inverted papilloma (IP) lesions and to determine whether HPV is involved in the progression of IP to sinonasal squamous cell carcinoma (SCC).

STUDY DESIGN

A retrospective study was performed on 14 patients diagnosed with IP within the last 12 years. Three of these 14 patients developed SCC.

METHODS

Eighteen formalin-fixed, paraffin-embedded tissue blocks were obtained for these 14 patients. After DNA extraction, polymerase chain reaction (PCR) was performed, followed by hybridization using HPV 6, 11, 16, 18, 31, 33, 35, 45, and 52 specific DNA probes, in an attempt to identify HPV type in each specimen. After RNA extraction, the integration status of the HPV genome was evaluated based on the relative abundance of E7 and E5 viral transcripts, assessed by quantitative real-time PCR.

RESULTS

HPV sequences were detected in samples from 3 of the 14 patients with IP. Of the three patients with SCC, HPV sequences were detected in two patients, whereas one patient was negative for the oligoprobes tested. Of the 11 patients diagnosed only with IP, 1 patient was positive for HPV DNA (HPV type 11). This difference in HPV positivity between IP and SCC was not statistically significant (P = .09, Fisher's Exact test, two tailed). Viral transcripts were detected in both patients with SSC who were HPV positive. Because HPV early transcripts are polycistronic, loss of 3' transcript sequences (E5) and retention of 5' sequences (E7) indicates integration. One of the SSC containing HPV 18 sequences showed a E7/E5 ratio of 776:1. The other SSC showed E7 transcripts and an absence of E5 transcripts

CONCLUSION

HPV transcripts were present in SCC positive for HPV, and the relative level of E7 to E5 transcripts indicates integration of the viral genome. These findings are suggestive of HPV having an active role in the lesion. More extensive studies are needed to determine the exact role of HPV in IP and progression to SCC.

HPV infections in benign and malignant sinonasal lesions

This review updates the evidence that the human papillomavirus (HPV) is involved in the development of benign and malignant sinonasal lesions. Since the early 1980s, when evidence was provided on the possible involvement of HPV in the aetiology of both benign respiratory papillomas and squamous cell carcinomas, a substantial number of studies have explored this issue. To date, 33.3% of sinonasal papillomas and 21.7% of sinonasal carcinomas analysed have been shown to be positive for HPV. Many elements of the data parallel the observations made in HPV lesions at other mucosal sites, such as malignant transformation and frequent recurrence after radical treatment; the fact that low risk HPV types 6 and 11 are usually confined to benign lesions, whereas the reverse is true for the oncogenic HPV types 16 and 18; and the presence of squamo-columnar junctions and squamous cell metaplasia in the sinonasal system. The discrepancies reported by several studies might result in part from technical reasons, but it is also possible that sinonasal lesions have a heterogeneous aetiology (HPV related and non-related) and/or that some novel (yet unidentified) HPV types exist in these lesions, which are detected by some studies but not by others.