Occupational risk factors for sinonasal inverted papilloma: a case-control study

The Clinical Characteristics in Children with Sinonasal Inverted Papilloma: A Case Report and Review of the Literature

Sinonasal inverted papilloma (SNIP) is one of the most common benign epithelial tumors but rarely occurs in children. The case of a 9-year-old Chinese boy, who presented with a left maxillofacial hump, nasal obstruction, and left nasal cavity and maxillary sinus masses under nasal endoscopy, is reported. The lesion was first diagnosed as a sinonasal tumor. However, to our surprise, the mass was determined to be an inverted papilloma after a detailed histological examination. We retrospectively reported the clinical data of this case and reviewed the relevant literatures on SNIP. This report aims to provide new insights into the clinical characteristics in children with SNIP and improve the understanding of this disease.

Clinical outcomes of sinonasal inverted papilloma: a retrospective analysis of 139 cases

OBJECTIVES

Sinonasal inverted papilloma has a high tendency for recurrence, local bone destruction and risk of malignant transformation. Therefore, complete resection of the tumour is required, and close follow up is essential. This article describes the clinical outcomes, recurrence rate and malignant transformation rate of sinonasal inverted papilloma.

METHODS

In this study, 139 patients diagnosed with sinonasal inverted papilloma in our hospital from December 2010 to May 2022 were retrospectively analysed. All patients underwent endoscopic surgery.

RESULTS

Sinonasal inverted papilloma occurred more often in males than in females. The mean age of patients with sinonasal inverted papilloma was 67.3 ± 5.7 years at diagnosis. The most prevalent site of origin was the maxillary sinus (50.4 per cent). The recurrence rate was 5.75 per cent, and the malignant transformation rate was 6.5 per cent.

CONCLUSION

All patients in this study underwent endoscopic surgery. Meticulous resection and regular long-term follow ups are crucial to reducing sinonasal inverted papilloma recurrence after surgery.

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.

Long-term outcomes in sinonasal squamous cell carcinoma arising from inverted papilloma: Systematic review

Long-term survival and recurrence patterns of squamous cell carcinoma arising from inverted papilloma (IP-SCC) have not been thoroughly investigated. Four electronic databases were searched and primary studies describing overall survival (OS), recurrence, and mean time to recurrence of patients with IP-SCC were included for review. Our search yielded 662 studies. The 28 studies selected for inclusion identified 663 patients with IP-SCC. In 596 patients with reported T classification, 439 (73.7%) were T3/T4 on presentation. Of the 650 participants with recurrence data (local, regional, and distant), 155 (23.8%) experienced a recurrence, with an aggregate mean time-to-recurrence of 24.3 months. In 565 patients with 5-year OS rates, the aggregate 5-year OS was 62%. Based on the literature to date, IP-SCC is associated with a 5-year OS rate of 62%. 23.8% of patients experienced recurrence at a mean time of 24.3 months, suggesting the need for long-term surveillance.

Exposure to occupational hazards and risk of sinonasal epithelial cancer: results from an extended Italian case-control study

OBJECTIVES

There is sufficient evidence for a causal association of sinonasal epithelial cancers (SNEC) only for exposure to wood and leather dusts, nickel compounds and employment in isopropyl alcohol production. The aim of this study was to assess whether other occupational hazards are associated with the risk of SNEC for the main histologic types, namely adenocarcinoma (AD) and squamous cell carcinoma (SCC).

METHODS

The study population included 375 incident SNEC cases collected from 1996 to 2014 (79% of all diagnosed SNEC) throughout the Piedmont region by the regional Sinonasal Cancer Registry, and 408 hospital controls. Exposure to 17 occupational agents was assigned through expert assessment based on interviews to the subjects on jobs held throughout their working life. The relationship of SNEC with ever and cumulative exposure to the hazards was assessed through unconditional logistic regression models adjusted for age, sex, area of residence, smoking habit, year of enrolment and coexposures.

RESULTS

AD was associated with both ever and cumulative exposure to wood dust, leather dust and organic solvents, and with cumulative exposure to textiles dusts. SCC risk was significantly increased by ever exposure to nickel, chromium and welding fumes, as well as by cumulative exposure to welding fumes, arsenic and organic solvents. A mixed group of other histological types was associated with both ever and cumulative exposure to wood dust and textile dusts.

CONCLUSIONS

The associations of SNEC with wood dust, leather dust and nickel were confirmed, while some new associations were observed for other hazards, which merit further investigation.

EGFR and BRAF mutations in inverted sinonasal papilloma - a more complex landscape?

Inverted (Schneiderian) sinonasal papilloma (ISP) is a neoplasm derived from mucosa of the sinonasal tract characterized by local aggressive growth, a tendency to recur and an association with sinonasal carcinoma. The etiology of ISP remains unclear. Recently, identical mutations in exons 19 and 20 of the oncogene EGFR were reported in ISP and ISP-associated sinonasal carcinoma. Nevertheless, it remains unclear whether recurring ISPs show identical EGFR mutations at different time points or whether these mutations are identical throughout the respective ISP sample. We used Sanger sequencing to test 60 formalin-fixed paraffin embedded ISP samples from 40 patients regarding mutations in exons 19 and 20 of EGFR—together with exon 15 of BRAF. Overall, 32 samples of 22 patients showed a mutation in EGFR exon 20, whereas 28 samples of 18 patients showed none. No mutation in EGFR exon 19 was found in any sample. Four samples of four patients showed a BRAF exon 15 mutation. Interestingly, samples of four patients exhibited genetic heterogeneity, enabling us to report this in ISP for the first time.

Low Epstein-Barr virus count in sinonasal inverted papilloma

Background: Sinonasal inverted papilloma (SIP) is a benign tumour originating from the sinonasal mucosa showing an extensive growth pattern, a high risk of recurrence and a 5-10% risk to malignify. Epstein-Barr virus (EBV) is an oncogenic herpesvirus which infects most individuals via the saliva eliciting a latent infection. Previous studies have been reporting variable data on EBV in SIP, and there is no present appreciation regarding the association between these.Aims/objectives: The aims were to investigate the presence and count of EBV in SIP and map the viral distribution in the epithelium versus the connective tissue.Material and method: Fifty-three SIP patients were identified in the Pathology Department register at the University Hospital of Umeå. The biopsies were analysed with Epstein-Barr Encoded Region (EBER) in situ hybridization. EBER-positive cells were counted in the epithelium and connective tissue.Results: We found EBER-stained cells in 30% of the cases, where 19% of these had an abundance of stained cells, and the rest showed a low count.Conclusions/significance: These findings demonstrate a low EBV count in SIP. EBV is less likely to be a causative agent in the formation of SIP, or its malignant transformation.

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

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

Human papillomavirus and infiltration of CD8- and Foxp3-positive immune cells in sinonasal inverted papillomas

Background: Sinonasal inverted papilloma (IP) is a benign tumor with a high risk of local recurrence and a potential to malignify and Human papillomavirus (HPV) has been suggested an etiological factor. p16INK4a (p16) overexpression is considered a surrogate marker for HPV, but whether p16 and HPV correlate to IP is uncertain. Besides, a prognostic role of tumor infiltrating lymphocytes (TILs) are observed in many tumors, however their role in IP is sparsely studied. Aims/objectives: We hence analyzed IPs for the presence and the prognostic role of HPV and p16 overexpression together with CD8+ and FoxP3+ TILs in a population-based study. Material and methods: 98 IP patients diagnosed 2001-2010 were identified from the Swedish Cancer Registry and analyzed for HPV by PCR and p16, CD8 and FoxP3 was by immunohistochemistry. Results: In total, 12.2% of the IPs were HPV-positive (nine HPV-11, two HPV-6 and one HPV-45). Patients with HPV-positive lesions were younger (p = .003) and tended to present with more dysplasia. No correlation was observed between TILs and prognosis. Conclusions and significance: Our data suggests that patients with HPV-positive IPs present with different clinical characteristics, suggesting possibly different disease entities. Moreover, recurrences may occur >5 years, which should be considered in the follow-up.

Clinical Implications of Carcinoma In Situ in Sinonasal Inverted Papilloma

Objective

Sinonasal inverted papilloma (IP) is a typically benign sinonasal tumor with a tendency to recur and the potential for malignant transformation. Varying degrees of dysplasia may be present, of which carcinoma in situ (CIS) is most advanced. We hereby describe the biological and clinical behavior of IP with CIS (IPwCIS).

Study Design

Retrospective cohort.

Setting

Tertiary academic referral center.

Subjects and Methods

Patients who underwent surgical resection for IP between 2002 and 2017. Pertinent clinical data were obtained, and all IPwCIS cases were histologically confirmed.

Results

In total, 37 of 215 cases (17.2%) were identified with IPwCIS. Mean age was 57 years and 86.5% of patients were male. Median follow-up was 82 months, and the recurrence rate was 27%. The maxillary sinus was the most common primary site (37.8%) and 14 tumors (37.8%) demonstrated multifocal attachment, which was associated with recurrence (odds ratio [OR], 9.7; 95% confidence interval [CI], 1.4-112.8; P = .028). IPwCIS was also associated with multiple recurrences (OR, 2.71; 95% CI, 1.246-5.814; P = .021). Most patients were treated with surgery alone (89.1%) and 4 patients received adjuvant radiotherapy (8.1%). Only 1 patient (2.7%) demonstrated malignant transformation after definitive surgery.

Conclusions

IPwCIS represents the most severe degree of dysplasia prior to malignant transformation and is associated with higher recurrence rate and multifocal involvement but low rate of conversion to invasive carcinoma. The need for adjuvant therapy remains controversial, and further research into the etiology of the disease is warranted.

Malignant Versus Benign Tumors of the Sinonasal Cavity: A Case-Control Study on Occupational Etiology

Case-control studies on malignant sinonasal tumors and occupational risk factors are generally weakened by non-occupational confounders and the selection of suitable controls. This study aimed to confirm the association between sinonasal malignant tumors and patients' occupations with consideration for sinonasal inverted papillomas (SNIPs) as a control group. Thirty-two patients affected by adenocarcinoma (ADC) and 21 non-adenocarcinoma epithelial tumors (NAETs) were compared to 65 patients diagnosed with SNIPs. All patients were recruited in the same clinical setting between 2004 and 2016. A questionnaire was used to collect information on non-occupational factors (age, sex, smoking, allergies, and chronic sinusitis) and occupations (wood- and leather-related occupations, textile industry, metal working). Odds ratios (OR) with 95% confidence intervals (CI) associated with selected occupations were obtained by a multinomial and exact logistic regression. Between the three groups of patients, SNIP patients were significantly younger than ADC patients (p = 0.026). The risk of NAET increased in woodworkers (OR = 9.42; CI = 1.94⁻45.6) and metal workers (OR = 5.65; CI = 1.12⁻28.6). The risk of ADC increased in wood (OR = 86.3; CI = 15.2⁻488) and leather workers (OR = 119.4; CI = 11.3⁻1258). On the exact logistic regression, the OR associated to the textile industry was 9.32 (95%CI = 1.10⁻Inf) for ADC, and 7.21 (95%CI = 0.55⁻Inf) for NAET. Comparing sinonasal malignant tumors with controls recruited from the same clinical setting allowed demonstrating an increased risk associated with multiple occupations. Well-matched samples of cases and controls reduced the confounding bias and increased the strength of the association.

Comprehensive analysis of HPV infection, EGFR exon 20 mutations and LINE1 hypomethylation as risk factors for malignant transformation of sinonasal-inverted papilloma to squamous cell carcinoma

Different risk factors are suspected to be involved in malignant transformation of sinonasal papillomas and include HPV infection, tobacco smoking, occupational exposure, EGFR/KRAS mutations and DNA methylation alterations. In our study, 25 inverted sinonasal papillomas (ISPs), 5 oncocytic sinonasal papillomas (OSP) and 35 squamous cell carcinomas (SCCs) from 54 patients were genotyped for 10 genes involved in EGFR signalling. HPV-DNA detection was performed by in-situ hybridisation and LINE-1 methylation was quantitatively determined by bisulphite-pyrosequencing. High-risk HPV was observed only in 13% of ISP-associated SCC and in 8% of de novo-SCC patients. EGFR mutations occurred in 72% of ISPs, 30% of ISP-associated SCCs and 17% of de novo-SCCs. At 5-year follow-up, SCC arose in only 30% (6/20) of patients with EGFR-mutated ISPs compared to 76% (13/17) of patients with EGFR-wild-type ISP (p = 0.0044). LINE-1 hypomethylation significantly increased from papilloma/early stage SCC to advanced stage SCC (p = 0.03) and was associated with occupational exposure (p = 0.01) and worse prognosis (p = 0.09). In conclusion, our results suggest that a small subset of these tumours could be related to HPV infection; EGFR mutations characterise those ISPs with a lower risk of developing into SCC; LINE-1 hypomethylation is associated with occupational exposure and could identify more aggressive nasal SCC.

Inverted schneiderian papilloma of the supraglottis: Case report

Inverted schneiderian papillomas are rare benign tumors, most often arising from the sinonasal mucosa. We describe a case of a 59-year-old female with an inverted papilloma of the supraglottis. This is the first reported case of a supraglottic-presenting inverted papilloma. Although rare, this case demonstrates that these tumors should be considered during workup of supraglottic laryngeal masses. Laryngoscope, 127:2830-2832, 2017.

Long-term follow-up of a patient with malignant transformation of inverted papilloma into sinonasal undifferentiated carcinoma

INTRODUCTION

Inverted papillomas (IP) are benign sinonasal neoplasms, which account for 0.5-4% of all nasal tumors. IPs have been known to transform into squamous cell carcinoma in 5-15% of cases. Rarely, transformations to other malignancies have been reported. Here we report a unique case of malignant transformation of an IP into sinonasal undifferentiated carcinoma (SNUC).

METHODS

A case report with a literature review; institutional review board exempted. The clinical presentation, radiographic features, surgical intervention, histopathologic analysis, treatment, and outcome of the case were examined.

RESULTS

A 62-year-old man presented with a 3-month history of nasal airway obstruction, rhinorrhea, and postnasal drip refractory to medical therapy. He had a long history of exposure to fumes, chemicals, dusts, and solvents as a professional painter as well as a 45 pack-year history of smoking and alcohol abuse. The patient was ultimately found to have a left ethmoidal IP with a focus of malignant transformation into SNUC. Endoscopic resection was performed, followed by concurrent chemoradiation and adjuvant chemotherapy. After surgery, he had no evidence of recurrent disease after 9 years of follow-up.

CONCLUSIONS

IP is known to transform into squamous cell carcinoma. Here we report a rare case of malignant transformation into SNUC, a much more uncommon and aggressive lesion. Although traditionally associated with a poorer prognosis, the positive outcome for SNUC observed in this patient may potentially be attributed to early detection and timely therapeutic intervention.

Advances in recurrence and malignant transformation of sinonasal inverted papillomas

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

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

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

The analysis of expression of p16 protein in group of 53 patients treated for sinonasal inverted papilloma

Introduction

Sinonasal inverted papilloma constitute relevant therapeutic problem due to destructive character of growth, tendency to recur and the possibility of malignant transformation. Therefore, many attempts to identify risk factors for inverted papilloma occurrence have been undertaken, as well as research to find markers that would allow for the earlier detection of tumors and the application of adequate therapy. A widely known risk factor of inverted papilloma is HPV infection. One of the markers of HPV infection and the ongoing effect of this change (although arousing some controversy) is the expression of the p16 protein.

Objective

The aim of the study was to analyze the correlation between the expression of p16 as a surrogate of HPV infection in analyzed histopathological material and epidemiological variables, recurrences or malignant transformation.

Methods

The retrospective study includes a group of 53 patients (18 women and 35 men) undergoing treatment for sinonasal inverted papilloma in the period of 2002–2012. The intensity of the p16 protein in histopathological material was scored as: 0 – no expression, 1 – diffuse expression (borderline) and 2 – positive expression; or 0 – no expression/diffuse expression (borderline); 1 – positive expression. The Ethics Committee agreement was obtained (1089/12; 245/13).

Results and conclusion

There was no statistically significant relationship between the expression of p16 and the age of patients, cigarette smoking, tumor location, tumor staging according to the Krouse and Cannady classification, the presence of dysplasia or the occurrence of relapse.

The rapid change in sinonasal inverted papilloma incidence - the epidemiological analysis

In recent years, the incidence of sinonasal inverted papilloma (IP) in a stable population has increased significantly. The aim of the study was to analyze the occurrence of IP between the years 2002-2012 in relation to epidemiological factors in an unalterable area. Moreover, we wanted to start a discussion about the difficulties in determining the inci¬dence of benign lesions that are not included in registers. This retrospective study included a group of 69 patients who were treated in the Department of Otolaryngology, ENT Oncology, Poznań University of Medical Sciences. In 2006, we noticed a sudden change in referrals. We compared two groups of patients who were referred during two differ¬ent time periods: 11 patients (2002-2006) and 58 patients (2007-2012). Despite a marked difference in the number of patients, there were no differences between the groups in tumor location (p>0.05), stage (p=0.16), duration of symp¬toms (p=0.39), place of residence, and smoking (p=0.41). The patient`s age was the only variable that differed significantly between the groups (48.45 vs. 56.93 years; p=0.043569, respectively).

Management of inverted papilloma: review

BACKGROUND

Inverted papilloma is the most common benign tumour affecting the nose. There is a high rate of recurrence and a potential of malignant transformation. This review article aimed to identify the best available management of this pathology today.

METHOD

A systematic review of the current English-language literature was performed. Only original articles with a minimum follow up of one year and an average follow up of two years were included.

RESULTS

A total of 1385 patients from 16 case series were identified. The total recurrence rate for all patients was 11.5 per cent. Significantly lower recurrence rates were found for procedures using an attachment-oriented excision (recurrence of 6.9 per cent; p = 0.0001) and utilising frozen sections (recurrence of 7.0 per cent; p = 0.0001).

CONCLUSION

There is a general trend towards endoscopic surgery. There may be some benefit to the use of attachment-oriented surgery and frozen sections. Multi-centred randomised controlled trials are required.

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.

Metallothionein 2A core promoter region genetic polymorphism and its impact on the risk, tumor behavior, and recurrences of sinonasal inverted papilloma (Schneiderian papilloma)

Inverted papillomas are a unique group of locally aggressive benign epithelial neoplasms in the nasal cavity and paranasal sinuses arising from the Schneiderian mucosa. Metallothioneins are sulfhydryl-rich heavy metal-binding proteins required for metal toxicity protection and regulation of biological mechanisms including proliferation and invasion. The goal of this study was to identify three SNPs at loci −5 A/G (rs28366003) and −209 A/G (rs1610216) in the core promoter region and at locus +838 C/G (rs10636) in 3′UTR region of the MT2A gene with IP risk and with tumor invasiveness according to Krouse staging. Genotyping was performed using the PCR restriction fragment length polymorphism technique in 130 genetically unrelated IP individuals, and 418 randomly selected healthy volunteers. The presence of the rs28366003 SNP was significantly related to the risk of IP within the present population-based case-control study. Compared to homozygous common allele carriers, heterozygosity and homozygosity for the G variant had a significantly increased risk of IP (adjusted odds ratio [OR] = 7.71, 95 % confidence interval [CI]: 4.01–14.91, p_dominant < 0.001). Moreover, risk allele carriers demonstrated higher Krouse stage (pT1 vs. pT2-4) (OR = 19.32; 95 % CI, 2.30–173.53; p < 0.0001), diffuse tumor growth (OR = 4.58; 95 % CI, 1.70–12.11; p = 0.0008), bone destruction (OR = 4.13; 95 % CI, 1.50–11.60; p = 0.003), and higher incidence of tumor recurrences (OR = 5.11; 95 % CI, 1.68–15.20; p = 0.001). The findings suggest that MT2A gene variation rs28366003 may be implicated in the etiology of sinonasal inverted papilloma in a Polish population.