Human papillomavirus: An unlikely etiologic factor in sinonasal inverted papilloma

[Inverted papilloma of the nose and paranasal sinuses : Diagnosis, treatment, and malignant transformation]

Inverted papilloma (IP) are benign tumors that show a locally aggressive behavior, a high rate of recurrence, and a potential for malignant transformation. Specific radiological signs such as hyperostosis at the origin of the IP and convoluted cerebriform patterns, as well as the typical endoscopic aspect, can lead to diagnosis and enable preoperative planning of surgical access and the extent of surgery. Endonasal endoscopic techniques are considered the gold standard and the introduction of extended surgical techniques such as the prelacrimal approach, frontal drillout, or orbital transposition facilitate complete subperiosteal resection with preservation of important physiological structures. There is a risk of synchronous and metachronous squamous cell carcinomas (IP-SCC). Research focuses on radiological criteria to differentiate benign IP from IP-SCC, genetic and epigenetic factors in the process of malignant transformation, and estimation of the risk of IP progressing to IP-SCC.

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.

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.

Sinonasal Papillomas: 10-Year Retrospective Analysis of Etiology, Epidemiology, and Recurrence

OBJECTIVES

To examine the epidemiology, subtypes, trends over time, and predictive factors for recurrence and malignant transformation of sinonasal papillomas.

METHODS

A retrospective chart review of 118 patients with sinonasal papillomas from 2009 to 2019 was conducted at the University of California, Los Angeles. This study is a follow-up to a previously published study from 2000 to 2009 at the same academic center.

RESULTS

The mean age was at presentation was 58.5 years, with a 2:1 male to female ratio, and average follow-up of 30.1 months. The rate of recurrence after complete resection was 19% with an average of 32.6 months to recurrence. The time to recurrence followed a bimodal distribution with 57% of cases recurring within 24 months (mean = 10) and 43% from 40 to 103 months (mean = 61). The proportion of the inverted papillomas rose from 38% in 2000-2004 to 89.6% in 2015-2019. Patients presenting at a younger age had a higher chance of recurrence (mean age 52 with recurrence vs. 61 without recurrence). Age did not correlate with histopathologic transformation in surgical pathology. Furthermore, histopathological transformation did not raise the chance of recurrence. Smoking, alcohol use, chronic rhinosinusitis, and allergic rhinitis were not associated with any of the outcome measures in this study. The most significant factor predicting recurrence, beside age at presentation, was the history of two or more prior sinus surgeries for papillomas or other reasons (OR = 3.52 and 5.81).

CONCLUSION

This study explored the features of sinonasal papillomas as well as the risk factors for recurrence and transformation. Younger age at presentation and two or more prior surgeries for papillomas were associated with recurrence. Time to recurrence followed a bimodal distribution, with late recurrences happenning from 40 to 103 months after surgery, emphasizing the importance of long-term follow-up for timely resection of tumors and prevention of malignancy.

Increased Neutrophil Infiltration and Epithelial Cell Proliferation in Sinonasal Inverted Papilloma Compared to Contralateral Nasal Polyps

BACKGROUND

Sinonasal inverted papilloma (IP) is a rare and benign epithelial tumor in the sinonasal tract. Recent study suggested the potential role of chronic inflammation in the pathogenesis of IP. This study aims to compare the inflammatory pattern, the capacity of epithelial cell proliferation and EGFR mutation status of unilateral IP with contralateral polyp tissue.

METHODS

Sixteen patients with unilateral IP and contralateral nasal polyps (NP) were identified through a retrospective chart review. The neutrophil and eosinophil infiltration in IP and NP were assessed by immunostaining for neutrophil elastase and major basic protein (MBP). Immunohistochemistry was also used to assess the expression of FoxM1, Ki67 and cyclin D1 in IP tissue and contralateral NP. Sanger sequencing was used to evaluate the EGFR mutations.

RESULTS

The neutrophil count in IP was significantly higher than contralateral NP and 68.8% patients presented with neutrophilic inflammation, whereas only 37.5% contralateral NP tissue showed neutrophilic inflammation. The percentage of positive FoxM1-staining cells was significantly increased in IP, and positively correlated with the percentage of cells with positive staining for cyclin D1 and ki67 as well as neutrophil counts. EGFR exon 20 insertions were detected in 14 (87.5%) IP samples and no EGFR mutations were found in contralateral NP sample.

CONCLUSION

Our study demonstrated distinct inflammatory pattern between IP and contralateral NP and implied the oncogenic role of neutrophils in the pathogenesis of IP. EGFR mutations may be the early event to initiate IP development by enhancing epithelial cell proliferation.

HPV-Positive Status Is an Independent Factor Associated With Sinonasal Inverted Papilloma Recurrence

OBJECTIVES

The present study aimed to evaluate human papillomavirus (HPV) occurrence in sinonasal inverted papilloma (SNIP), and to assess factors associated with HPV positivity and SNIP recurrence.

STUDY DESIGN

Prospective study.

METHODS

We prospectively collected clinical data and fresh tissue specimens from 90 consecutive patients treated for SNIP at Helsinki University Hospital, between 2015 and 2019. Fourteen patients with recurrent SNIP underwent repeated tumor sampling. All tissue specimens were analyzed for the presence of HPV. Factors associated with SNIP recurrence and HPV positivity were assessed.

RESULTS

Among 107 SNIP specimens, 14 (13.1%) were positive for low-risk HPV and 6 (5.6%) were positive for high-risk HPV. HPV positivity was associated with an increased risk of recurrence (P = .004). Smoking was significantly associated with HPV positivity in SNIP (P = .01), but a history of HPV-related diseases or patient sexual habits did not correlate with HPV positivity. The recurrence rate was lower among patients with SNIP that underwent an attachment-oriented resection, compared to patients treated without attachment-oriented resections (78.6% vs 25.8%, P < .001).

CONCLUSIONS

The risk of SNIP recurrence was highly associated with 1) HPV positivity and 2) surgery without an attachment-oriented resection. Oncogenic HPV was rare in SNIP.

LEVEL OF EVIDENCE

3 Laryngoscope, 2021.

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.

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.

Clinicopathological analysis of low-grade papillary Schneiderian carcinoma: report of five new cases and review of the literature

AIMS

Low-grade papillary Schneiderian carcinoma (LGPSC) is a rare and newly described entity of the sinonasal tract. The aim of this study was to evaluate the clinicopathological and molecular characteristics in order to identify typical features for differential diagnosis.

METHODS AND RESULTS

Of the 3000 cases of sinonasal tumour studied during a period of 6 years, five cases were reviewed and diagnosed as LGPSC. All five patients were female (mean age, 47.8 years; range, 18-64 years) and had undergone multiple surgeries (3-10 surgeries). Both the sinonasal tract and the middle ear were involved in four patients. Nodal metastasis occurred in two patients, and one patient developed a distant metastasis to the left lung. Histologically, tumours had branched and crowded papillae with pushing boundaries. Tumour epithelia were multilayered and arranged in an orderly pattern without cilia. No malignant cytological features were observed in any of the cases. Immunohistochemical findings revealed a scattered distribution of Ki67-positive cells and positive staining for epithelial membrane antigen, mainly in the outermost-layer cells. Human papillomavirus (HPV) DNA was found in two patients and genotyped as HPV type 16. Sanger sequencing did not reveal any epidermal growth factor receptor or Kirsten rat sarcoma viral oncogene homologue gene mutation in the five cases.

CONCLUSIONS

We report on five new cases of LGPSC, and confirm LGPSC as a new sinonasal carcinoma that behaves aggressively with metastatic potential. The combination of clinical behaviour and typical histological features can distinguish LGPSC from sinonasal papilloma and other carcinomas.

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.

First case of Ethmoid Metastasis From an Induced Oropharyngeal Squamous Cell Carcinoma HPV, Interest of the P16 as a Diagnosis Aid

We describe the first case of ethmoid metastasis from an oropharyngeal human papillomavirus-induced squamous cell carcinoma using the anti-P16 immunohistochemistry. The p16 overexpression can be a valuable aid in the differential diagnosis.

A clinical analysis of sinonasal squamous cell carcinoma: a comparison of de novo squamous cell carcinoma and squamous cell carcinoma arising from inverted papilloma

Background: Sinonasal squamous cell carcinoma (SCC) is a rare tumor arising either de novo or in association with inverted papillomas (IPs).Objectives: The aim of this study was to investigate and compare the oncological features and prognosis of patients with sinonasal SCCs based on their etiology.Material and methods: The medical records of 117 patients who had been diagnosed with de novo SCC or those arising from IP (IP-SCC) were retrospectively reviewed. In situ hybridization analyses to detect HPV 16/18DNA and p16 immunohistochemistry were also performed in 10 cases with IP-SCC.Results: The three-year disease-specific survival (DSS) rate was higher in cases with T1, 2 and 3 than in cases with T4 in both tumor groups. T4 cases with de novo SCC had a better DSS than those with IP-SCCs. HPV16/18 was not detected in any of the 10 IP-SCCs.Conclusions and significance: T4 cases with de novo SCC tended to have a better DSS than those with IP-SCC. Since some T4 patients with IP-SCC were found to have a highly aggressive disease, careful treatment planning should be performed. High-risk HPV may not play a vital role in the carcinomatous transformation of most IP-SCC cases.

Prevalence of human papillomavirus in sinonasal squamous cell carcinoma with and without association of inverted papilloma in Eastern China

Background

Information on HPV-associated sinonasal squamous cell carcinoma (SNSCC) is very limited in China. The aim of this study was to determine the prevalence of HPV in a large cohort of SNSCC patients in China.

Methods

Clinical records and formalin-fixed and paraffin-embedded tumor specimens from 30 SNSCC patients with associated inverted papilloma (IP-SNSCC) and 84 de novo SNSCC (DN-SNSCC) patients were retrieved between 2010 and 2017. HPV status was determined for each specimen using a combination of p16 immunohistochemistry and GP5+/6+ PCR.

Results

Immunohistochemistry for p16 was positive in two IP-SNSCC patients (2/30, 6.7%) and in 16 DN-SNSCC patients (16/84, 19.0%). HPV DNA was detected in six IP-SNSCC patients (6/30, 20%) and in three DN-SNSCC patients (3/84, 3.8%). Expression of p16 was not correlated with the presence of HPV DNA (p = 0.150). Among 18 p16-positive SNSCC patients, only three were HPV DNA-positive. Furthermore, only three of nine HPV DNA-positive tumors exhibited high p16 expression. In IP-SNSCC patients, only one of six HPV DNA-positive tumors exhibited high p16 expression. In DN-SNSCC patients, two of three HPV DNA-positive tumors exhibited high p16 expression. The positive rates for both HPV DNA and p16 in IP-SNSCC patients and DN-SNSCC patients were 3.3 and 2.4%, respectively.

Conclusions

Immunostaining for p16 is not a reliable surrogate marker of HPV status in SNSCC. The presence of HPV is rarely detected in DN-SNSCC patients in Eastern China. IP-SNSCC patients frequently lack of p16 overexpression despite the presence of high-risk HPV DNA.

Clinical evidence based review and systematic scientific review in the identification of malignant transformation of inverted papilloma

Background

Inverted papilloma (IP) is an unusual type of benign tumor that has high recurrence rates and the potential to transform into squamous cell carcinomas (SCC). The mechanism of the transformation process from IP to IP-SCC is uncertain and there is no consensus regarding the best practice for IP-SCC detection. The goal of this study is to identify the best clinical methods to detect for IP-SCC.

Methods

An evidence-based review was performed using Medline and Ovid to obtain all articles up to October 10th, 2019 pertaining to identification of IP malignant transformation. All manuscripts discussing clinical methods or biomarkers were included.

Results

Based on clinical research studies, convoluted cerebriform pattern and apparent diffusion coefficient values on Magnetic Resonance Imaging (MRI) can help differentiate benign IP from SCC and increased SUVmax on PET/CT is associated with higher probability of malignancy although not as specific. No consensus about the best biomarker for IP-SCC has been reached among researchers and continues to be exploratory.

Conclusion

Endoscopy with biopsy is the gold standard practice to identify IP-SCC; however, MRI is the preferred imaging modality to recognize malignant transformation in cases where biopsy is difficult. Multiple biomarkers have shown positive results, but no single indicator with clinical significance for monitoring malignant transformation process has been found.

Clinical management of emerging sinonasal malignancies

Several emerging sinonasal malignancies have recently been described in the pathology literature. Although not all distinctly classified by the World Health Organization, these rare tumors present a management challenge to surgeons and oncologists. While prior studies have summarized histologic details, a clinically focused review is currently lacking in the literature. This review describes the presentation, histopathology, imaging, treatment, and prognosis of newly described or recently evolving sinonasal malignancies while highlighting the distinguishing features of these entities. It includes teratocarcinosarcoma, human papillomavirus-related multiphenotypic carcinoma, biphenotypic sinonasal sarcoma, sinonasal renal cell-like adenocarcinoma, NUT-midline carcinoma, squamous cell carcinoma associated with inverted papilloma, sinonasal undifferentiated carcinoma, and INI-1-deficient sinonasal carcinoma. By describing the diagnosis, treatment, and prognosis of these recently defined entities, this clinical review aims to help guide oncologists in the clinical management of these patients.

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.

Squamous cell carcinoma associated with inverted papilloma: Recurrence and prognostic factors

The purpose of the present study was to review the recurrence and prognostic factors of squamous cell carcinoma (SCC) associated with inverted papilloma (IP). A retrospective chart review was conducted on 21 patients with SCC associated with IP, in the nasal cavity and paranasal sinuses, between March 2007 to March 2017. All patients underwent surgical treatment: Surgery prior to or following adjuvant therapy was performed in 17 patients (81.0%). During a mean follow-up time of 47.4 months (range, 3-123 months), 9 patients (42.9%) experienced local recurrence, and the risk factors of T4 stage and invasive orbital cavity had a significant influence on recurrence. The 1-, 3-, and 5-year overall survival rates were 90.5, 75.4 and 68.5%, and the 1-, 3-, and 5-year disease-specific survival (DSS) rates were 90.5, 80.4 and 80.4%, respectively. The prognosis of patients with stage T4 was not satisfactory compared with those with stage T3 or less, and a positive surgical margin was also significantly associated with poor survival. Overall, SCC associated with IP has a favorable DSS, early diagnosis and complete resection of lesions is required for a good prognosis. Furthermore, aggressive surgical approaches combined with postoperative adjuvant therapy seem to be effective in tumors at stage T4.

Low prevalence of human papillomavirus infection in sinonasal inverted papilloma and oncocytic papilloma

The aim of this study was to investigate the role of human papillomavirus (HPV) in sinonasal inverted papilloma (SIP) and sinonasal oncocytic papilloma (SOP) from a single institution and whether p16 can serve as a surrogate marker for HPV infection. This study included 49 subjects with SIP and 36 subjects with SOP. Formalin-fixed paraffin-embedded tissues were used to extract genomic DNA, and HPV detection was performed by utilizing a valid nested polymerase chain reaction approach that can detect all known HPV subtypes. Immunohistochemistry was used to evaluate the expression of p16 in all tumor sections. The presence of HPV DNA was found in 6.1% (3/49) of the SIP patients and 11.1% (4/36) of the SOP patients. All identified HPV subtypes in SIP were high-risk HPV, including HPV-16 (two patients) and HPV-58 (one patient). Regarding SOP, there were three patients positive for HPV-16 and one with low-risk HPV (type 6). In total, 11/49 (22.4%) SIP lesions and 10/36 (27.8%) SOP lesions were considered p16 positive, with p16 staining in more than 70% of tumor cells. There was only one SIP and one SOP that were positive for both HPV (high-risk HPV type 16) and p16 staining. HPV does not play an etiologic role in inverted papilloma or oncocytic papilloma of the sinonasal region. p16 immunostaining should not be used as a surrogate marker to evaluate the HPV infection status in these lesions.

Sinonasal inverted papilloma: rate of recurrence and malignant transformation in 44 operated patients

Introduction

Although sinonasal inverted papillomas are benign lesions, they are locally aggressive and have a potential malignant transformation ranging from 5% to 15%, with a high recurrence rate.

Objective

The aim of this article is to describe the rate of recurrence and malignant transformation in patients with a diagnosis of inverted papilloma who underwent surgery in a tertiary hospital in São Paulo.

Methods

We performed a retrospective analysis of patients diagnosed with sinonasal papilloma who had undergone surgery in a tertiary hospital in São Paulo, between August 1998 and August 2017. A patient chart review was conducted to assess data of patients’ demographics, tumors characteristics, follow-up appointments, recurrence and malignancy. Inverted papillomas were analyzed and classified under the Krouse staging system.

Results

A total of 69 surgeries were performed in patients with diagnosis of sinonasal papilloma. Inverted papilloma was the most prevalent subtype (49 cases ‒ 80.33%), followed by exophytic papilloma (6 cases ‒ 9.84%) and by oncocytic papilloma (6 cases – 9.84%). The recurrence rate was 34.09% for inverted papilloma (15/44) and the mean time of recurrence was 24.6 months. Malignant transformation occurred in 6 patients (13.64%). Three of these patients presented carcinoma in the first surgery and three patients developed carcinoma during the follow-up.

Conclusion

The high recurrence rate and malignancy potential allow us to consider inverted papillomas as aggressive tumors. In a tertiary hospital in São Paulo the recurrence rate the mean time to recurrence is 24.6 months. The recurrence after 10 years implies was 34.09% and the need for long-term follow up. It is possible that the high recurrence rate and the high malignant transformation rate we found are due to the large number of tumors discovered at an advanced stage (most of them staged T3 and T4), secondary to poor access to health system, in developing countries.

EGFR and KRAS mutations in Chinese patients with sinonasal inverted papilloma and oncocytic papilloma

AIMS

Sinonasal inverted papilloma (SIP) and sinonasal oncocytic papilloma (SOP) are uncommon, benign epithelial neoplasms located in the sinonasal region, that have the potential for malignant transformation. A recent study reported that EGFR and KRAS mutations occurred in the majority of Western patients with SIP and SOP, respectively. The aims of this study were to investigate the prevalence of KRAS and EGFR mutations in Chinese SIP and SOP patients, and to study the association between molecular alterations and their clinical features.

METHODS AND RESULTS

We retrospectively collected 80 sinonasal papilloma specimens, including 44 cases with SIP, 33 cases with SOP, and three cases with mixed sinonasal papilloma, which harboured elements of both inverted and oncocytic types. Formalin-fixed paraffin-embedded tissues were used to extract genomic DNA, and EGFR and KRAS mutations were evaluated with direct Sanger sequencing. Thirty-five (78%) SIP patients harboured EGFR mutations, and all mutations were exon 20 insertions, whereas no KRAS mutations were detected. In contrast, KRAS mutations were detected in 82% of SOP patients, but no EGFR mutations were detected. Among the three mixed-type cases, two harboured both EGFR exon 20 insertions and KRAS mutations. Another case harboured a KRAS mutation, but no EGFR mutation was detected.

CONCLUSION

SIP and SOP are two clinical entities with different genetic mutational patterns of EGFR and KRAS. Mixed types with elements of both SIP and SOP may harbour both EGFR and KRAS mutations.

Mapping of human papilloma virus, p16, and epstein-barr virus in non-malignant tonsillar disease

Objectives

Due to their location in the entrance of the aero-digestive tract, tonsils are steadily exposed to viruses. Human papilloma virus (HPV) and Epstein-Barr virus (EBV) are two potentially oncogenic viruses that tonsils encounter. The incidence of HPV positive tonsillar cancer is on the rise and it is unknown when infection with HPV occurs.

Aim

To investigate if tonsils are infected with HPV and EBV, to study the co-expression of HPV and its surrogate marker p16, and to evaluate the number of EBV positive cells in benign tonsillar disease.

Materials and Methods

Tonsils from 40 patients in a university hospital were removed due to hypertrophy, chronic or recurrent infection. These were analyzed for presence of HPV, its surrogate marker p16, and EBV. HPV was studied using PapilloCheck (a PCR method), while p16 was identified in epithelial and lymphoid tissue with immunohistochemistry and EBV using EBER-ISH (Epstein-Barr encoding region-in situ hybridization).

Results

HPV was not detected, and p16 was present at low numbers in all epithelial samples as well as in 92.5% of the lymphoid tonsillar samples. At least one EBER-positive cell was seen in 65% of cases. Larger numbers of EBER-expressing cells were only seen in two cases.

Conclusion

These findings demonstrate that EBV and HPV infect tonsils independently, but further studies are warranted to confirm their infectious relationship.

Level of Evidence

Cross-sectional study.

Surgical outcomes of sinonasal inverted papilloma: a 17 year review

Introduction

Inverted papillomas represent one of the most common benign neoplasic lesions located in the sinonasal tract. Owing to the local erosive behavior, tendency to recur and the potential for malignant transformation, surgical management of inverted papillomas is often challenging.

Objective

This study aimed to analyze the surgical outcomes of patients with inverted papillomas, according to the Krouse staging and the different surgical approaches.

Methods

Retrospective study of patients diagnosed with sinonasal inverted papillomas who underwent surgical treatment between 2000 and 2016 at a tertiary referral hospital. Cases with follow-up less than 12 months were excluded. The rate and the time of recurrence were the main outcomes. Values of p < 0.05 were considered statistically significant.

Results

Thirty-six cases with mean age of 60 years, predominantly male (72%), were included. The follow-up period ranged from 1 to 16 years, with an average of 4.5 years. Krouse T1 Stage corresponded to 11.1%; T2 occurred in 50% of cases; while T3 and T4 Stages accounted for 30.6% and 8.3% of patients, respectively. Most cases were approached by an endoscopic technique alone (83.3%), with a recurrence rate of 13.3%. Patients treated via a combined or open approach revealed a recurrence of 16.7%. No differences in the recurrence rate were reported when comparing endoscopic surgery with the open or combined techniques. Krouse Stage T3 had a significant association with inverted papillomas recurrence (p = 0.023). All inverted papilloma relapses occurred up to 2 years post-operatively. One case of malignant transformation was recorded (2.7%).

Conclusion

Endoscopic surgery did not increase the recurrence rates and can be a safe and efficient alternative to open or combined techniques. The recurrence of inverted papillomas seem to be related to the persistence of the disease and tend to occur early after primary surgery. Krouse T3 Stages may be associated with a higher recurrence of inverted papillomas.