Schneiderian papillomas: comparative review of exophytic, oncocytic, and inverted types

Comprehensive analysis of DNA methylation gene expression profiles in GEO dataset reveals biomarkers related to malignant transformation of sinonasal inverted papilloma

BACKGROUND

DNA methylation may be involved in the regulation of malignant transformation from sinonasal inverted papilloma (SNIP) to squamous cell carcinoma (SCC). The study of gene methylation changes and screening of differentially methylated loci (DMLs) are helpful to predict the possible key genes in the malignant transformation of SNIP-SCC.

MATERIALS AND METHODS

Microarray dataset GSE125399 was downloaded from the Gene Expression Omnibus (GEO) database and differentially methylated loci (DMLs) were analyzed using R language (Limma package). ClusterProfiler R package was used to perform Gene Ontology (GO) analysis on up-methylated genes and draw bubble maps. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and its visualization analysis were analyzed to speculate the possible key Genes in SNIP-SCC malignant transformation. Subsequently, SNIP cases archived in our department were collected, tissue microarray was made, and immunohistochemical staining was performed to analyze the expression levels of UCKL1, GSTT1, HLA-G, MAML2 and NRGN in different grades of sinonasal papilloma tissues.

RESULTS

Analysis of dataset GSE125399 identified 56 DMLs, including 49 upregulated DMLs and 7 downregulated DMLs. Thirty-one genes containing upregulated DNA methylation loci and three genes containing downregulated DNA methylation loci were obtained by methylation microarray annotation analysis. In addition, KEGG pathway visualization analysis of 31 up-methylated genes showed that there were four significantly up-methylated genes including UCKL1, GSTT1, HLA-G and MAML2, and one significantly down-methylated gene NRGN. Subsequently, compared with non-neoplasia nasal epithelial tissues, the expression of HLA-G and NRGN was upregulated in grade I, II, III and IV tissues, while the expression of MAML2 was lost. The protein expression changes of MAML2 and NRGN were significantly negatively correlated with their gene methylation levels.

CONCLUSIONS

By analyzing the methylation dataset, we obtained four up-regulated methylation genes UCKL1, GSTT1, HLA-G and MAML2 and one down-regulated gene NRGN. MAML2, a tumor suppressor gene with high methylation modification but loss of protein expression, and NRGN, a tumor gene with low methylation modification but upregulated protein expression, can be used as biological indicators to judge the malignant transformation of SNIP-SCC.

International Consensus Statement on Allergy and Rhinology: Sinonasal Tumors

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Unique clinical and prognostic behavior of patients diagnosed with combined exophytic and inverted papilloma histologic subtype

Objectives

To evaluate the clinical and prognostic behaviors of sinonasal papillomas.

Methods

Patients diagnosed with sinonasal papilloma were reviewed between 2001 and 2016 at a tertiary rhinology practice. Using pathology-specific electronic medical record software, patients diagnosed with sinonasal papilloma were identified. Four subcategories of this lesion were identified: inverting (IP), exophytic (EP) oncocytic (OP) and inverting + exophytic (IP + EP) papillomas.

Results

A total of 107 patients were identified with unique sinonasal papilloma diagnoses. Of these, the majority were diagnosed with IP (87, 81.3%). The subpopulation of patients co-diagnosed with IP and EP (IP + EP) was unique with respect to clinical presentation and prognosis relative to both the IP and EP alone populations. IP + EP patients (5, 4.7%) were older with an average age of 75.25 years compared to 45 (EP) and 55.26 (IP), p < .0001. IP + EP patients more often presented with epistaxis (60%) compared to 33.3% (EP) and 4.6% (IP). Finally, all IP + EP patients had at least one recurrence of their disease, compared to 33.3% (EP) and 28.5% (IP).

Conclusions

Each histopathologic subtype of sinonasal papilloma has unique clinical characteristics and recurrence rates after surgical resection. The subpopulation of patients diagnosed with IP + EP tends to be older, more likely to present with epistaxis, and more likely to recur. Additional investigation and analysis of this subpopulation is warranted.

Level of Evidence

4.

Update from the 5th Edition of the WHO Classification of Nasal, Paranasal, and Skull Base Tumors: Imaging Overview with Histopathologic and Genetic Correlation

Sinonasal and skull base tumors are a heterogeneous group of neoplasms with considerable histologic variation and overlapping imaging features. In 2022, the World Health Organization updated the head and neck tumor classification, further emphasizing the importance of molecular data and genetic alterations in sinonasal neoplasms. The changes include the addition of new entities and discussion of emerging entities, as well as changes to the taxonomy and characterization of tumors. The new classification focuses on entities that develop in these sites either exclusively (eg, olfactory neuroblastoma) or most frequently. Another change includes reduction in the number of categories by creating separate category-specific chapters for soft-tissue, hematolymphoid, and neuroectodermal lesions. In this review, we briefly discuss the various categories in the new classification with a more detailed description of the 2 new entities (SWItch/Sucrose Non-Fermentable complex-deficient sinonasal carcinomas and human papillomavirus-related multiphenotypic sinonasal carcinoma). We also highlight the emerging entities including IDH-mutant sinonasal malignancies and DEK-AFF2 carcinoma, presently classified as sinonasal undifferentiated carcinoma and nonkeratinizing squamous cell carcinoma, respectively.

Sinonasal Inverted Papilloma: A Narrative Review

Inverted papilloma (IP) is a relatively rare sinonasal benign lesion, peculiar in its etiology, clinical presentation and treatment. Its resemblance to other sinonasal pathologies and varied approaches, makes it an interesting disease. Recently there have been several advances in the management of IP. This article aims to summarize the contemporary developments thus enabling the readers to understand the years of research behind IP. To integrate the available literature on IP and study the current scenario in its management. A comprehensive literature review was done on Google Scholar and PubMed database using the following key words: "inverted papilloma", "Schneiderian", "sinonasal", "medial maxillectomy". Articles published in English were used. Articles published till May 2020 were reviewed. Years of research have aimed to gain more information regarding the epidemiology, histopathology, staging systems and surgical management of IP. To briefly summarize the research so far, it is safe to say that there exists an association between Human Papilloma Virus and IP. The Krouse staging system is the most commonly used. The treatment itself has changed from a conservative approach to a more aggressive excision with or without external approach and with or without chemoradiotherapy. In IP, whether or not associated with SCC, complete surgical removal of the tumour is advocated as the treatment of choice. With the advancements in endoscopic technique, surgeons have been using it to their advantage for the surgical evaluation and cure of IP, depending upon the stage. Endoscopic treatment is preferred, whereas for lesions less accessible endoscopically, or in those with peripheral extension, open surgery is indicated. Every patient requires counselling before discharge and thorough examination during the follow-up to detect any evidence of recurrence.

Middle Ear Primary Oncocytic Schneiderian Papilloma: A Case Report

Introduction

Chronic otitis media is a significant health problem, but middle ear and mastoid neoplasms, either benign or malignant, are extremely rare.

Case Report

Here is a report from a 51-year-old female who presented persistent otorrhea with an aural polyp. The patient was operated on with the probable diagnosis of cholesteatoma. During surgery, a fragile mass was discovered, and histopathologic examination reported the diagnosis of a primary oncocytic Schneiderian papilloma. Microscopically it has pseudostratified epithelium of columnar cell epithelium with eosinophilic granular cytoplasm and hyperchromatic nuclei. The treatment of choice for Schneiderian papillomas is complete surgical removal.

Conclusions

Although very rare, oncocytic Schneiderian papilloma should be considered a differential diagnosis of ear neoplasms such as auditory canal polyps.

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.

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

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

Case Report: Oncocytic Schneiderian Papilloma Originating From the Sphenoid Sinus

A rare case of oncocytic Schneiderian papilloma originating from the sphenoid sinus characterised, for 3 years, by non-specific symptoms of severe headache, a block of nasal breathing, and deprecating sense of smell was presented by an elderly female patient. Sphenoid sinus functional endoscopic sinus surgery (FESS), with a one-block tumour excision, through an endonasal approach, with a histological study of removed tumour masses, were performed on the patient. Long observation in the post-operative period was necessary, considering the risk of recurrence and malignancy of oncocytic Schneiderian papilloma (OSP). Although the oncocytic papilloma of the sphenoid sinus is rare, non-specific symptoms make this pathology easily misdiagnosed. Thus, any isolated unilateral process in the paranasal sinuses with long-existing symptoms must be given careful attention due to the chance of this process being an inverted papilloma with malignization. CT scan indicating a unilateral opacification of paranasal sinuses with local calcifications is a typical manifestation, and endoscopic sphenoidotomy can be recommended as a treatment of choice.

A case report of exophytic nasal papilloma with acute dacryocystitis as the first symptom

Background

This study aims to explore a case of exophytic nasal papilloma with acute dacryocystitis as the first symptom.

Case presentation

A 72-year-old male patient complaining of “a 10-year history of tearing and purulent discharge from the right eye, with subsequent redness and pain in the inner canthus for three days” was initially diagnosed with acute dacryocystitis of the right eye. The patient was treated with anti-inflammatory therapy. However, the redness and swelling of the inner canthus continued to increase. An endoscopic dacryocystorhinostomy of the right eye was performed under general anesthesia. A large amount of purulent secretion was drained during the operation. As a result, the swelling of the inner canthus was significantly reduced. A routine intra-operative biopsy of the wall of the lacrimal sac revealed an exophytic nasal papilloma. A second biopsy, 1 week after the surgery, revealed the same result. The patient was advised to undergo a dacryocystectomy once the swelling had subsided. However, the patient was reluctant to undergo this surgery and remains under clinical observation.

Conclusion

It is rare for an exophytic nasal papilloma, which is a benign tumor in the lacrimal sac, which has the potential for recurrence and malignant transformation, to manifest with acute dacryocystitis as the first symptom. Therefore, this case report could provide a reference for the future clinical diagnosis of this disease.

A Systematic Review of Definitive Treatment for Inverted Papilloma Attachment Site and Associations With Recurrence

OBJECTIVE

Inverted papilloma (IP) is the most common benign neoplasm of the nasal cavity with known risk of recurrence. There is no standardized approach to definitive treatment for attachment sites. This systematic review aims to determine whether surgeon choice of technique differs by anatomic attachment site and whether different surgical techniques contribute to reduced rates of recurrence.

DATA SOURCES

PubMed and Ovid Medline.

REVIEW METHODS

A systematic review was conducted for studies reporting on IP. Those that included IP recurrence rates and primary tumor attachment site were reviewed.

RESULTS

Of 122 published studies, 14 met eligibility criteria, representing 585 patients and a recurrence rate of 5.8%. The maxillary sinus (50.9%) was the most common primary attachment site, and the sphenoid sinus was associated with the highest rate of recurrence (10.4%). The most utilized technique included debulking the tumor, removing mucosa over the attachment site, and drilling the underlying bone. The most common Krouse stage represented was T3 (53.3%). No single technique predicted a propensity for recurrence, but certain techniques are favored depending on IP attachment site. Finally, frozen sections to obtain evidence of clear margins intraoperatively significantly reduced rates of recurrence (3.4% vs 7.3%, P = .045).

CONCLUSION

Based on the current literature, the most common technique to address site of attachment involves resecting mucosa and drilling the tumor base. Choice of technique appears to differ for various sites of attachment. Use of intraoperative frozen section analysis appears to be associated with decreased recurrence overall.

LEVEL OF EVIDENCE

3.

Conjunctival Exophytic Schneiderian-type Papillomas: A Rare Occurrence

Conjunctival papillomas are common tumors that exhibit an exophytic growth pattern, comprised of multiple filiform fronds of squamous epithelium that contain fibrovascular cores. The inverted (endophytic) variety of papilloma, often termed "Schneiderian," rarely occurs on the conjunctiva, with only 15 cases reported to date. Endophytic and exophytic papillomas are well described arising in the sinonasal Schneiderian epithelium where a low rate of malignant transformation may occur in the endophytic type; malignant transformation in exophytic sinonasal papillomas is exceedingly rare. The authors describe 2 cases of exophytic conjunctival papillomas with the morphology of a sinonasal or Schneiderian-type papilloma. Both were pink, sessile acquired growths in women in the sixth decade of life involving the inferior conjunctival fornix or nasal limbus. Nonkeratinizing squamous epithelium along with numerous goblet cells, intraepithelial mucinous cysts, and microabscesses were present. Immunohistochemistry showed reactivity for cytokeratin 7 and wild-type staining for p16 and p53, paralleling the findings in common conjunctival papillomas; both were also driven by low-risk human papillomavirus.

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.

MRI features of different types of sinonasan rhabdomyosarcomas: a series of eleven cases

OBJECTIVE

To retrospectively analyze magnetic resonance imaging (MRI) features of various pathological subtypes of sinonasal rhabdomyosarcoma (RMS) and explore correlations between imaging features and pathological subtypes.

METHODS

In total, 11 cases with embryonal, alveolar or pleomorphic sinonasal RMSs, confirmed by surgical pathology, were selected. Their characteristics and distinctive imaging features were analysed, and the correlation between pathology and imaging features was explored.

RESULTS

Bone destruction was observed in all 11 cases with RMS. Expansive growth was predominant in three alveolar and three embryonal RMS cases, and creeping growth was predominant in two alveolar, two embryonal and one pleomorphic RMS cases. Signs of residual mucosa were observed in all 11 cases, and 10 cases showed involvement of multiple sinus cavities and orbital cavities. All cases exhibited mild-to-intermediate enhancement.

CONCLUSION

Sinonasal RMSs have the following characteristic MRI features: ethmoid sinuses and middle nasal conchae are the prevalent sites; lesions are mainly of mild enhancement; tumours exhibit signs of residual mucosa, mild-to-intermediate enhancement and frequent orbital involvement; bone invasion and bone destruction are frequently observed; and haematogenous metastasis is not as common as lymphatic metastasis. RMSs of various pathological subtypes were not significantly distinct by imaging.

Sine Qua Non: Sinonasal Inverted Papilloma

Inverted papilloma (IP) is a common proliferation of squamous epithelial cells of the sinonasal tract. Although considered benign, IP is known to cause local destruction, has a high rate of recurrence, and a low, but significant rate of malignant transformation. Differentiating an IP from its histologic mimickers is essential for appropriate risk stratification and long-term surveillance. A classic case of sinonasal inverted papilloma is discussed.

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

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

COX-2 Overexpression in Schneiderian Papillomas

Background

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

Objective

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

Methods

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

Results

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

Conclusion

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

Human papilloma virus induced oropharyngeal inverted papilloma as a precursor to laryngeal papillomatosis in A 1 year old child

Inverted papillomas are rare tumors in the pediatric population and have not been reported in children less than two years. These tumors may produce respiratory distress in patients, particularly if they ectopically occur in the airway. Human papilloma virus is one of the known etiologies for many head and neck neoplasms including inverted papillomas and squamous papillomas. We report a child who was surgically treated at fifteen months of age for inverted papilloma of the pharynx who subsequently developed squamous papilloma of the larynx which persisted as a recurrent respiratory papillomatosis. This is the first such reported case to our knowledge.

Need for long-term follow-up in sinonasal inverted papilloma: A Single-institution experience

BACKGROUND

Most studies on sinonasal inverted papillomas (SNIPs) regarding risk factors for recurrence, recurrence rates (RRs) and malignant transformation are biased by a significant proportion of revision cases.

METHODS

Retrospective study on patients with consecutive, treatment-naïve SNIPs at a tertiary referral center between 1999 and 2019.

RESULTS

Overall, RR was 9.8% (10 of 102 patients), with 2 of 10 recurrences (20%) occurring after more than 5 years. Histopathological workup revealed synchronous malignancy in 2 of 102 patients (2%). Subgroup analysis revealed a significantly higher RR for SNIPs involving the frontal sinus (26.3% vs 6.0%, P = .02). No SNIPs primarily originating from the frontal sinus were observed.

CONCLUSION

Overall, RR of treatment-naïve SNIPs is comparably low; however, long-term follow-up is mandatory due to late recurrences. Secondary involvement of the frontal sinus was identified as risk factor for recurrence. No SNIPs primarily originating from frontal sinus were observed.

Prolapsed tongue papilloma cured by administration of the traditional Japanese (Kampo) herbal medicine, Keishibukuryogan-ka-yokuinin: A case report

Squamous papilloma is a benign mass lesion of the oral mucosa. For papillomas of the tongue, surgery is recommended owing to their malignant potential; however, certain complications may be associated with surgery. A traditional Japanese (Kampo) herbal medicine, Keishibukuryogan-ka-yokuinin (KBGY), has been used to treat viral warts and various skin diseases in Japan. Therefore, the effect of KBGY on papillomas is promising. A 49-year-old Japanese man presented with a wart on his tongue that was about 3 months old. He smoked 5 cigarettes per day. He did not drink alcohol. He had no history of malignant illnesses. He was taking alprazolam for panic disorder. The patient was diagnosed with a suspected papilloma of the tongue at the Department of Otolaryngology and was advised to undergo an excision biopsy to exclude malignancy. However, he refused owing to the fear of an invasive procedure. After informed consent was obtained from the patient, KBGY was prescribed. Three months later, the wart on his tongue spontaneously prolapsed. The histopathological diagnosis was squamous papilloma. There was no indication of malignancy, and the patient discontinued Kampo treatment. He has had no recurrence in the past 3 years. KBGY is a combination of Keishibukuryogan and yokuinin (adlay seeds). Keishibukuryogan may be beneficial for skin or oral mucosal remodeling, and yokuinin may have antiviral properties. The present case report suggests the use of KBGY as an appropriate complementary therapy for squamous papilloma.

Sinonasal Squamous Cell Carcinoma: Etiology, Pathogenesis, and the Role of Human Papilloma Virus

PURPOSE OF REVIEW

Sinonasal squamous cell carcinoma (SNSCC) is a rare disease with considerable histologic diversity. Currently, there is a poor understanding of the etiology and pathogenesis of SNSCC. Here, we review recent literature to summarize what is known regarding (1) the etiology of SNSCC, (2) the role of Human Papilloma Virus (HPV) in SNSCC, and (2) the molecular underpinnings of SNSCC.

RECENT FINDINGS

1. High risk HPVappears to play a role in the pathogenesis of a subset of SNSCCs. SNSCCs with high risk HPV have improved survival compared with those without HPV and occur in patients who are younger, similar to HPV mediated oropharyngeal cancer. 2. A subset of inverted papillomas have transcriptionally active low-risk HPV and have a higher risk of transformation, while low risk HPV negative inverted papillomas frequently have EGFR mutations.

SUMMARY

SNSCC is a diverse disease with likely multiple etiologies including carcinogen, irritant exposure, and HPV. While not definitively proven, evidence supports a role for high-risk HPV in a subset of SNSCC, and low-risk HPV in a subset of inverted papillomas which transform to SNSCC. In-depth molecular and genomic studies are needed in SNSCC to better understand the genomic underpinnings and oncogenic drivers.

Identification of Rare and Common HPV Genotypes in Sinonasal Papillomas

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

Sinonasal papillomas: A single centre experience on 137 cases with emphasis on malignant transformation and EGFR/KRAS status in "carcinoma ex papilloma"

Among the three major histological subtypes of sinonasal papillomas, inverted (ISP) and oncocytic (OSP) sinonasal papillomas tend to undergo malignant transformation to carcinoma. However, criteria determining risk of recurrence and malignant progression have not been established. Recently, EGFR and KRAS mutations were detected to be characteristic for ISP and OSP, respectively. In this study, we analyzed 137 sinonasal papilloma cases (132 ISP and 5 OSP) for clinicopathological characteristics, frequency of recurrences/malignant transformation, and histological types and genetic features of carcinoma ex Schneiderian papilloma. OSP presented at a higher age than ISP (median, 75 vs. 57 years) and affected predominantly females. Overall frequency of recurrences and malignant transformation was 23.1% and 9.5%, respectively. Rates of recurrence (33.3% vs. 22.0%) and malignant transformation (33.3% vs. 8.8%) were higher in OSP compared to ISP, respectively. Carcinomas (n = 10) occurred mostly synchronously, more frequently in females and mainly associated with ISP (n = 9). Squamous cell carcinoma (SCC) was the most frequently associated malignancy. Concordant EGFR (in ISP/associated carcinoma) and KRAS (in the OSP/associated carcinoma) mutations were detected in all successfully analyzed matching papilloma/carcinoma pairs, confirming their shared clonal origin. Results of this large study are in line with recent studies showing frequent EGFR and KRAS mutations in sinonasal carcinoma ex Schneiderian papilloma. As the papilloma component might on occasion be missed on biopsy of synchronous carcinoma ex papilloma, EGFR and KRAS mutation testing represents a promising molecular surrogate for sinonasal "carcinoma ex papilloma", at the same time offering an opportunity for targeting mutant EGFR in this rare cancer type.

Bilateral simultaneous sino-nasal inverted papilloma; A report of two cases and literature review

Introduction

Inverted Papilloma is a benign sinonasal tumor with a high recurrence rate and potential for malignant transformation, it typically presents as an obstructing unilateral nasal mass, atypical presentations include bilateral involvement which occurs in up to 5 % of cases.

Case presentation

Here we present two different cases of bilateral inverted papilloma, both presented complaining of bilateral nasal obstruction, the second case also had associated nasal polyposis and history of multiple previous endoscopic sinus surgeries, both cases were managed with endoscopic medial maxillectomy and tumor removal, with no signs of recurrence on follow up.

Conclusion

Bilateral involvement is an uncommon, atypical presentation of inverted papilloma, endoscopic surgery is a safe, reliable approach and it is the mainstay of treatment, regular endoscopic and clinical follow up is important for detection of recurrence.

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

PURPOSE AND METHODS

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

RESULTS

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

CONCLUSIONS

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

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: Efficacy of Demucosation to Reduce Recurrence After Surgical Managements

To compare the outcomes of various surgical approaches to resect sinonasal inverted papilloma and to discuss their advantages and disadvantages. A retrospective chart review of 61 consecutive patients with sinonasal inverted papilloma was performed. Surgical treatment included non-demucosation endoscopic sinus surgery (ESS), demucosation ESS, endonasal medial maxillectomy (EMM), Draf type 3, Caldwell-Luc surgery, Denker, Killian, and lateral rhinotomy. Recurrence rates were compared between endonasal and external approaches and between demucosation and non-demucosation. After the first curative surgery, the non-demucosation ESS, endonasal demucosation (demucosation ESS, EMM, and Draf type 3), and external surgery showed recurrence rates of 61.5%, (8/13), 0.0% (0/21), and 7.4% (2/27), respectively. A significantly lower recurrence rate was observed in the endonasal demucosation (p < 0.001) and in the demucosation ESS group (p < 0.001) in comparison with the non-demucosation ESS. However, as for recurrence rate, no statistically significant difference was observed between endonasal surgery and external surgery (p = 0.162). Demucosation is a better strategy for the treatment of inverted papilloma than is non-demucosation. Demucosation is the key procedure for preventing recurrence.

Giant Rhinosinusal Inverted Papilloma

Sinonasal papilloma is a benign tumor, derived from Schneiderian sinonasal epithelium. There have been described three histological subtypes: inverted, oncocytic and exophytic. The case presented here is A 66-year-old male patient, which was hospitalized in our Otolaryngology Department for a giant tumor, that was exteriorized from the left nostril, repeated epistaxis, nasal obstruction and anosmia. The computed tomography scan revealed an iodophilic and non-homogeneous tumor, with areas of necrosis, which included the entire left nasal cavity, with extension to the rhinopharynx and the left maxillary sinus. We completely removed the tumor by an endoscopic medial maxillectomy, with the subsequent histopathological examination revealing an inverted papilloma, with areas of low grade dysplasia and also areas with oncocytic Schneiderian papilloma. At the six-months postoperative control, there was no tumor recurrence. Major issues of this type of tumor is fast invasion capacity and numerous local recurrence. More recent studies have shown that these relapses are often overdue tumors.

Sinonasal Oncocytic Papilloma-A Series of 20 Cases With Special Emphasis on Recurrences

Objective

Reports on sinonasal oncocytic papilloma (SNOP) are scarce. The aim of this retrospective study was to evaluate the clinical features of this rarest form of sinonasal papilloma with special emphasis on the pattern of recurrences and on the potential factors predicting them.

Study Design

Retrospective study.

Methods

Between the years 1994 and 2016, 20 patients (mean age 66 years; range 30–87) were diagnosed with SNOP at the Department of Otorhinolaryngology–Head and Neck Surgery, HUS Helsinki University Hospital (Helsinki, Finland). Hospital charts were reviewed to record various medical and sociodemographic patient characteristics, and the archived histological specimens were re‐evaluated. Postoperative follow‐up time varied between 26 days and 167 months.

Results

Maxillary sinus was the most common (60%) tumor location. None of the tissue samples showed dysplasia. Recurrence rate was 39% and the median time span to the first recurrence was 25 months (range 7–71). Smokers had more often a recurrence than nonsmokers (75% vs. 31%). Patients with perioperative purulent rhinosinusitis during the primary surgery had a higher recurrence rate compared with those without (60% vs. 31%). Tumors located in the sinuses recurred more often than those located in the nasal cavity (45% vs. 29%). However, all these findings remained statistically nonsignificant. None of the cases showed malignant transformation during the follow‐up.

Conclusion

SNOP has a propensity to recur. History of smoking, purulent rhinosinusitis during the primary surgery, and tumor location in the sinuses outside the nasal cavity seem to contribute to an increased trend in the risk of recurrence.

Level of Evidence

4

Imaging of adult nasal obstruction

The commonest causes of nasal obstruction are rhinitis and chronic rhinosinusitis, which affect up to 30% and 14% of the adult population, respectively. The global financial burden is huge, estimated at $5 billion for rhinitis and $8.6 billion for chronic rhinosinusitis per annum in the USA. On referral for imaging, computed tomography (CT) is indicated initially when there is a suboptimal response to medical treatment of these mucosal diseases or there are "red flags," such as persistent unilateral obstruction, epistaxis, pain, and orbital or neurological symptoms. A mass visible at rhinoscopy or endoscopy in the nose or nasopharynx and lymphadenopathy are further indications. The anterior (cartilaginous) nose plays a key role in the aetiology of nasal obstruction as it accounts for 50-75% of the total resistance to airflow in the upper airway. It has been ignored in the imaging literature, but extensively evaluated by clinicians using a range of methods, including CT. Oblique reconstructions perpendicular to the parabolic curve of lamellar airflow provide accurate assessment of the anterior nose. A thorough and systematic approach to assessing the nose addresses the discrepancy between imaging and clinical evaluation of structural causes of nasal obstruction, especially septal deviation, reported in the surgical literature. Nasal tumours are a very uncommon cause of nasal obstruction; magnetic resonance imaging is commonly performed to assess their full extent and improve the specificity of diagnosis.

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.

A Case of Inverted Papilloma Originating from the Middle Ear and Review of the Literature

Inverted papilloma (IP) with malignant transformation is rarely seen in the middle ear. Up to now, there have been 16 primary middle ear IPs reported in the English literature. Even though it is very rare in the middle ear, this pathology should be kept in mind for the differential diagnosis of middle ear masses. In this case, we report a 77-year-old female who had recurrent IP with malignant transformation and complication.

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.

Attachment-oriented endoscopic surgical management for inverted papillomas in the nasal cavity and paranasal sinuses

OBJECTIVE

The treatment of all forms of sinonasal inverted papilloma (IP) is a complete, wide, local resection. The main surgical purpose is to remove all diseased mucosa and mucoperiosteum, together with a cuff of normal-looking mucosa at the attachment site, followed by drilling and/or coagulation. Our aim is to present our experiences in endoscopic surgical management of IP by using attachment-oriented excision.

METHODS

We present 20 cases of sinonasal IP. The data collected includes the histopathological diagnosis, staging, extension of the tumor, tumor attachment site, approach to surgery, serum squamous cell carcinoma antigen (SCCA) level, and recurrences.

RESULTS

All patients underwent endoscopic surgery. A Caldwell-Luc operation was required in addition to the endoscopic surgery in one case. There was one case of recurrence (5%). After the additional operation, there was no recurrence. The tumor attachment sites vary, and the case of recurrence had a wide attachment site at the primary surgery. No major intra- or post-operative complications were observed.

CONCLUSION

The present study shows that attachment-oriented excision for IP is useful for complete resection of IP. Surgeons should choose the surgical approach according to the location of the tumor attachment site rather than the Krouse staging system.

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).

MR imaging and CT features of oncocytic papilloma of the sinonasal tract with comparison to inverted papilloma

OBJECTIVE:

To evaluate and compare the imaging feature of sinonasal oncocytic papilloma (OP) with inverted papilloma (IP).

METHODS:

The CT and MR imaging manifestations of 17 pathology proven sinonasal OPs were reviewed and compared with 17 IPs randomly selected as a control group over the same period.

RESULTS:

Seventeen sinonasal OPs had unilateral occurrence and 16 of them (94.1%) had a lobulated configuration.The distribution of original sites differed significantly between OPs and IPs (p < 0.05).OPs (47.1%) particularly involved the maxillary sinus,while IPs (64.7%) usually arose from the lateral nasal wall.OPs exhibited isointense in 5 cases and grape- or patchy-like hyperintense in 12 on T₁ weighted image, and isointense in 13 and hyperintense in 4 on T₂ weighted image, with moderate enhancement. 10 OPs appeared as a Type II time intensity curve (TIC).There was significant difference of pre-contrast T₁ signal intensity between OPs and IPs (p < 0.05).The prevalence of the imaging findings of "focal osteitis" (11.8% vs 94.1%) and "cystic change" (94.1% vs 17.6%) differed significantly between OPs and IPs (p < 0.05), but not for "cerebriform"sign (82.4% vs 94.1%) (p > 0.05).

CONCLUSION:

Three imaging features including high signal on T₁ weighted image, cystic change and only a rare association of focal osteitis may help the diagnosis of OP distinguished from IP.

ADVANCES IN KNOWLEDGE:

The typical imaging characteristics should prompt an accurate diagnosis of sinonasal OPs in routine clinical practice. Combination of CT and MR imaging characteristics can be more helpful in discriminating OPs from IPs.

Optical imaging with a high-resolution microendoscope to identify sinonasal pathology

OBJECTIVES

High-resolution microendoscopy (HRME) is an optical imaging modality that allows real time imaging of epithelial tissue and structural changes within. We hypothesize that HRME, using proflavine, a contrast agent that preferentially stains cell nuclei and allows detection of cellular morphologic changes, can distinguish sinonasal pathology from uninvolved mucosa, potentially enabling real-time surgical margin differentiation.

STUDY DESIGN

Ex vivo imaging of histopathologically confirmed samples of sinonasal pathology and uninvolved, normal sinus epithelium.

SETTING

Single tertiary-level institution.

SUBJECTS AND METHODS

Five inverted papillomas, one oncocytic papilloma, two uninvolved sinus epithelia specimens, and three inflammatory polyps were imaged ex vivo with HRME after surface staining with proflavine. Following imaging, the specimens were submitted for hematoxylin and eosin staining to allow histopathological correlation.

RESULTS

Results show that sinonasal pathology and normal sinus epithelia have distinct HRME imaging characteristics. Schneiderian papilloma specimens show increased nuclear-to-cytoplasmic ratio, nuclear crowding, and small internuclear separation, whereas normal sinus epithelia specimens show small, bright nuclei with dark cytoplasm and relatively large internuclear separation. Inflammatory polyps, however, have varying imaging characteristics, that resemble both Schneiderian papilloma and normal sinus epithelia.

CONCLUSIONS

This study demonstrates the feasibility of HRME imaging to discriminate sinonasal pathology from normal sinus epithelia. While the system performed well in the absence of inflammation, discrimination of inflamed tissue was inconsistent, creating a significant limitation for this application. Novel imaging systems such as HRME with alternative contrast agents may assist with real-time surgical margin differentiation, enabling complete surgical resection of inverted papilloma and reducing recurrence rates.

Incidental Histopathologic Finding of Sinonasal Inverted Papilloma Among Surgically Excised Polyps Increases the Risk of Tumor Recurrence

Inverted papilloma (IP) is a benign tumor remarkable for its tendency toward recurrence. Local relapse implicates incomplete resection concerning the bone adjacent to tumor base. The high false negative rates on biopsies, mainly when nasal polyps coexist, may affect the surgical management and outcomes. Our objective was to study the impact of preoperative histologic diagnosis in IP recurrence, particularly in patients with pre-surgical diagnosis of inflammatory polyps. A retrospective analysis of 62 patients treated for IP was conducted. Demographic data and information about smoking status, alcohol intake, tumor location, histology, presence of nasal polyps, staging, malignancy, previous biopsies and surgical approach were evaluated to identify factors associated with recurrence. Prevalence of nasal polyps was higher in patients with recurrence. Smoking history, alcohol abuse, staging, histologic type, malignancy and surgical approach were not associated with recurrence. The presence of nasal polyps at endoscopy was inversely associated with the diagnosis of IP at incisional biopsy. Incidental histologic diagnosis of IP after surgery increased the risk of recurrence more than tenfold. Biopsy reporting the diagnosis of IP previous to surgery was inversely associated to recurrence. In patients with IP, coexistence of nasal polyps at initial endoscopy and lack of pathological IP diagnosis prior to surgery are strongly associated with a higher risk of recurrence. When excisional biopsy reports IP incidentally, an early revision surgery should be considered in order to avoid future aggressive surgeries because of tumor recurrence.

Exophytic sinonasal papillomas and nasal florid papillomatosis: A retrospective study

BACKGROUND

Sinonasal exophytic papillomas are rare. The multifocal form, florid papillomatosis, has not been yet described in literature. We report on the clinical features and the management of the different forms of exophytic papilloma.

METHODS

A retrospective study was conducted that included all patients with exophytic papilloma treated in our center over the past 12 years. We recorded clinical presentation, treatments, recurrences, pathology (p16 expression and human papillomavirus [HPV] status).

RESULTS

We included 13 patients with a mean follow-up of 5 years. The main location of exophytic papilloma was the anterior part of the septum. Lesions were multifocal in 3 patients corresponding to florid papillomatosis. The main treatment was surgery. Cases of HPV-11 or HPV-6 were present in all forms of exophytic papilloma (dysplasia in 4 cases). Late recurrences occurred in 3 patients (2 patients with florid papillomatosis) over a period of 3 years.

CONCLUSION

Exophytic papilloma has 2 clinical presentations: localized and diffuse. Patients with florid papillomatosis should be monitored closely as recurrence seems to be frequent.

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.

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.

The clinical behavior of sinonasal inverted papilloma with cellular dysplasia: case series and review of the literature

The prognosis and recurrence rate of inverted papilloma (IP) with concomitant cellular dysplasia are not well-delineated. Demographic, clinical and imaging data of all patients who were surgically treated for sinonasal inverted papilloma (SNIP) in our center between 1996 and 2013 were reviewed. Data regarding the coexistence of dysplastic changes or malignancy within the resected tissues were also retrieved. After the exclusion of malignant cases and patients who were lost for follow-up, 92 patients were included in the study. Five patients had coexisting cellular dysplasia (4.7%), four of them had severe dysplasia and one had mild-to-moderate dysplasia. All four cases with severe dysplasia recurred, three were primarily treated endoscopically and one by external approach. Only the case with mild to moderate dysplasia which had been treated by subcranial approach did not recur. Patients with dysplasia had significantly higher recurrence rate than patients without dysplasia (80 vs. 14%, p = 0.019). This significant relation between histology and recurrence remained even after adjustment to tumor extent. The adjusted odd ratio of dysplasia (dysplasia vs. no dysplasia) is 9.7, p = 0.043. SNIP with dysplasia should be treated aggressively and followed closely. The histopathologic investigation of SNIP specimens should always note the presence of dysplasia and its severity. Further investigation on the clinical behavior of SNIP with dysplasia is needed. Multicenter studies are warranted due to the rarity of dysplastic SNIP.

Complete response of skull base inverted papilloma to chemotherapy: Case report

Background:

Inverted papilloma (IP) is the most common benign sinonasal neoplasm. Endoscopic techniques, improved understanding of pathophysiology, and novel surgical approaches have allowed rhinologists to treat IPs more effectively, with surgery being the mainstay of therapy. Frontal sinus IP poses a challenge for surgical therapy due to complex anatomy and potentially difficult surgical access.

Objectives:

We reported a unique case of a massive frontal sinus IP that presented with intracranial and orbital extension, with near resolution after chemotherapy.

Methods:

A retrospective case review of a patient with a frontal sinus IP treated at a tertiary academic medical center.

Results:

A 75-year-old male patient presented with nasal obstruction, purulent nasal discharge, and a growing left supraorbital mass. Endoscopy demonstrated a mass that filled both frontal and ethmoid sinuses, with orbital invasion. There also was substantial erosion of the posterior table, which measured 1.73 × 1.40 cm. A biopsy specimen demonstrated IP with carcinoma in situ. The patient was deemed unresectable on initial evaluation and, subsequently, underwent chemotherapy (carboplatin and paclitaxel). The tumor had a dramatic response to chemotherapy, and the patient elected for definitive surgery to remove any residual disease. During surgery, only a small focus of IP was found along the superior wall of the frontal sinus. No tumor was found elsewhere, including at the site of skull base erosion. The final pathology was IP without carcinoma in situ or dysplasia.

Conclusion:

This was the first reported case of chemotherapeutic “debulking” of IP, which facilitated surgical resection, despite substantial intracranial and orbital involvement. Although nearly all IPs can be treated surgically, rare cases, such as unresectable tumors, may benefit from systemic chemotherapy.