Carcinoma ex-Schneiderian papilloma (malignant transformation): a clinicopathologic and immunophenotypic study of 20 cases combined with a comprehensive review of the literature

Microvessel barrier dysfunction in sinonasal inverted papilloma-associated squamous cell carcinoma and its manifestation in dynamic contrast-enhanced MRI

BACKGROUND

To date, an effective means to preoperatively predict the malignant transformation of sinonasal inverted papilloma (SIP) remains lacking due to similarities in clinical appearance. This study aimed to retrospectively evaluate dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) parameters and microvessel structure in tumors with histologically confirmed SIP and inverted papilloma-associated squamous cell carcinoma (IP-SCC), as well as correlate DCE-MRI findings with angiogenesis biomarkers.

METHODS

Absolute quantitative DCE-MRI parameters (Ktrans, Kep, Ve) based on the Tofts model and model-free semi-quantitative indices (Tpeak, WR, MaxSlope) of SIP (n = 22) and IP-SCC (n = 20) were investigated. Regions of interest (ROIs) were oriented according to the tumor subsites in the surgical records. Micro-vessel density (MVD) counts and tight junction protein (claudin-5) expression were evaluated in tumor specimens obtained during surgery. Differences in the above data were compared between the two groups. Correlations between DCE-MRI parameters and angiogenic biomarkers were analyzed.

RESULTS

Compared with SIP specimens, IP-SCC specimens were characterized by a significantly higher MVD and a leakier microvessel barrier. The values of Tpeak and Ve were significantly higher for SIP than those for IP-SCC, whereas WR, MaxSlope, and Kep were significantly lower, indicating early enhancement and a faster dispersion model in IP-SCC. MVD was positively correlated with WR and Kep and negatively correlated with Tpeak. Tpeak was slightly positively correlated to claudin-5 expression.

CONCLUSION

DCE-MRI can serve as a noninvasive biomarker of angiogenesis in the malignant transformation from SIP to IP-SCC. DCE-MRI may assist in the differentiation of malignancies and treatment selection.

Assessment of TP53 and CDKN2A status as predictive markers of malignant transformation of sinonasal inverted papilloma

The mechanism and predictive biomarkers of sinonasal inverted papilloma (IP) transformation into squamous cell carcinoma (SCC) are still unclear. We investigated the genetic mutations involved and the predictive biomarkers. Fourteen patients with SCC arising from IP and six patients with IPs without malignant transformation (sIP) were included. DNA was extracted separately from areas of normal tissue, IP, dysplasia, and SCC. Whole exome sequencing and immunohistochemistry was performed. Major oncogenic mutations were observed in the progression from IP to SCC. The most frequently mutated genes were TP53 (39%) and CDKN2A (27%). Mutations in TP53 and/or CDKN2A were observed in three of six IPs with malignant transformation (cIP); none were observed in sIPs. Tumor mutational burden (TMB) increased from IP to SCC (0.64/Mb, 1.11/Mb, and 1.25 for IP, dysplasia, and SCC, respectively). TMB was higher in the cIPs than in the sIPs (0.64/Mb vs 0.3/Mb). Three cIPs showed a diffuse strong or null pattern in p53, and one showed a total loss of p16, a distinct pattern from sIPs. Our result suggests that TP53 and CDKN2A status can be predictive markers of malignant transformation of IP. Furthermore, immunohistochemistry of p53 and p16 expression can be surrogate markers for TP53 and CDKN2A status.

Two Head and Neck Carcinomas With Squamous and Mucinous Components and Human Papillomavirus Associations: Maxillary Mucoepidermoid Carcinoma ex Sinonasal Schneiderian Papilloma and Tonsillar Invasive Stratified Mucin Producing Carcinoma (ISMC)

Carcinomas of the head-and-neck region with squamous and glandular/mucinous features constitute a heterogeneous group, with a significant minority of tumors showing an human papillomavirus (HPV) association. The differential diagnosis is usually between mucoepidermoid carcinoma (MEC) and adenosquamous carcinoma. We present here two tumors that exemplify both the challenges of diagnostic classification, as well as the complex relationship to HPV: (a) a low risk HPV positive/p16 negative carcinoma that is most consistent with a relatively typical intermediate grade mucoepidermoid type carcinoma with complete MEC phenotype (three cell types), originating from intranasal sinonasal papillomas with exophytic and inverted patterns, and invading surrounding maxillary compartments, and (b) a p16 and keratin 7 (KRT7) positive carcinoma of the right tonsil, characterized by stratified squamous and mucinous cell (mucocyte) features. Whereas the first tumor represents a typical MEC ex-Schneiderian papilloma, the second is morphologically most consistent with the, novel for this anatomic location, diagnosis of "invasive stratified mucin producing carcinoma" (ISMC), pointing to an analogy to similar, high-risk HPV-driven malignancies recently described in the gynecologic (GYN) and genitourinary (GU) areas. Both tumors, despite their mucoepidermoid-like features had no connection to salivary glands and lacked the MAML2 translocation typical of salivary gland MEC, pointing to a mucosal/non-salivary gland origin. Using these two carcinomas as examples, we attempt to address questions related to: (a) the histological distinction between MEC, adenosquamous carcinoma, and ISMC, (b) similarities and differences between these histological entities in mucosal sites versus morphologically similar salivary gland tumors, and (c) the role of HPV in these tumors.

[A case of sinonasal inverted papilloma with malignant transformation and distant metastasis: a 10-year follow-up report]

Sinonasal inverted papilloma（SNIP） is a kind of benign tumor originating from the nasal cavity and paranasal sinuses, accounting for 70% of papillomas. The incidence of the disease is more common in males, with an average age of 50-60 years. It is most likely to occur in unilateral maxillary sinus and ethmoid sinus, followed by sphenoid sinus and frontal sinus.It has the characteristics of local invasion, high recurrence rate and malignant tendency, and most malignant transformation into squamous cell carcinoma. Endoscopic nasal resection and appropriate adjuvant therapy can help to reduce the recurrence rate and inhibit further deterioration. We report the results of a 10-year follow-up of a SNIP patient, including the clinical manifestations, recurrence course and treatment plan during the 10 years. The patient underwent multiple nasal endoscopic surgeries, and had a recurrence of multiple focal attachment pattern, and finally had direct invasion and distant metastasis. Tumor recurrence and further deterioration persisted despite the use of a comprehensive treatment.

Evaluation of high-risk human papillomavirus in sinonasal papillomas and squamous cell carcinomas

The sinonasal tract is considered a second hotspot for human papillomavirus (HPV)-related tumors in the head and neck, with HPV being identified in up to 62% of squamous cell carcinomas (SCCs) and 38% of papillomas. There is limited data from geographical regions with low prevalence of high-risk (HR)-HPV on the association of HR-HPV in sinonasal neoplasms and on utility of p16 as a surrogate marker. p16 immunohistochemistry, HR-HPV mRNA ISH and quantitative real-time PCR (qPCR) were performed on a retrospective cohort of sinonasal papillomas and SCCs. KRAS mutation analysis was done in oncocytic papillomas. p16 positivity was present in 22/142 cases (15.5%) including eight inverted papillomas, one oncocytic papilloma (OP), and 13 SCC. Among these, mRNA ISH showed HR-HPV in the OP and two SCC, while another SCC was found to harbour HPV18 by qPCR. Two HPV-associated SCCs had foci of OP. mRNA ISH was negative in all p16 negative cases. p16 immunohistochemistry showed 68% concordance with mRNA ISH, and had sensitivity and negative predictive value of 100%; specificity was 67%, and positive predictive value was 14.3%. Association with HR-HPV in sinonasal papillomas and SCC is rare, and may be seen in cases demonstrating oncocytic morphology. p16 immunohistochemistry has low specificity and positive predictive value in low-prevalence populations; thus, reflex direct HR-HPV testing should be performed in p16 immunopositive cases. This two-step approach is viable in resource-limited settings, as the proportion of p16 positive cases is small.

Human papillomavirus expression in relation to biological behavior, Ki-67 proliferative marker, and P53 prognostic marker in Schneiderian papilloma

Various malignant and benign tumors can arise in the sinonasal cavity, including inverted papilloma (IP), a benign neoplasm with unique clinical characteristics. However, the mechanisms involved in the recurrence, occurrence, and malignant transformation of IP remain debatable. This study aimed to investigate the impact of human papillomavirus (HPV) infections on IP by comparing the number of infections in cases with epithelial tissue dysplasia and explore the predictive role of proliferative and prognostic markers in dysplasia. Tissue blocks from 35 cases of sinonasal papilloma, collected between 2015 and 2021 from the laboratory archives of the Medical City of Ghazi Al-Hererri Hospital in Baghdad, Iraq, were immunohistochemically stained with monoclonal antibodies (mAbs) to detect Ki-67 and p53. A quantitative immunohistochemical analysis was conducted to analyze the results. Polymerase chain reaction (PCR) was performed to detect HPV genotypes 16/18 and 6/11 in the tissues. There was an insignificant increase in Ki-67 and p53 expression in inverted papillomas with dysplasia. HPV11 was the most prevalent genotype in 34.3% of the patients, followed by HPV16 and HPV18 in 31.4% of the patients for each virus. The least common virus detected was human papillomavirus 6 (8.6%), which did not show any significant association with the degree of dysplasia. Viral detection proliferation and apoptosis had no impact on tumor dysplasia amongst all the patients, showing no relationship with the evaluated cases.

Sinonasal Adenosquamous Carcinoma - Morphology and Genetic Drivers Including Low- and High-Risk Human Papillomavirus mRNA, DEK::AFF2 Fusion, and MAML2 Rearrangement

BACKGROUND

Sinonasal adenosquamous carcinoma is rare, and there are almost no studies detailing morphology or characterizing their genetic driver events. Further, many authors have termed sinonasal tumors with combined squamous carcinoma and glands as mucoepidermoid carcinoma but none have analyzed for the presence of MAML2 rearrangement.

METHODS

Cases from 2014 to 2020 were collected and diagnosed using World Health Organization criteria. They were tested for p16 expression by immunohistochemistry (70% cut-off), DEK::AFF2 fusion by fluorescence in situ hybridization (FISH) and AFF2 immunohistochemistry, MAML2 rearrangement by FISH, and low- and high-risk HPV by RNA ISH and reverse transcription PCR, respectively. Detailed morphology and clinical features were reviewed.

RESULTS

There were 7 male (64%) and 4 female (36%) patients with a median age of 69 years, most Caucasian (10 of 11 or 91%). Most had tobacco exposure (8/11, 73%) and most presented with epistaxis, a visible nasal mass, and/or facial pain. Several had a precursor papillomas (3 of 11, 27%). The squamous component had variable keratinization, 5 of 11 (46%) of which would be described as keratinizing, 3 non-keratinizing, and 2 with mixed features. All had gland formation, by definition, and 2 of 11 (18%) had ciliated tumor cells. None of the 11 cases had MAML2 rearrangement and one had DEK::AFF2 fusion with associated positive nuclear AFF2 protein immunostaining. Most were p16 positive (7 of 11, 64%) and all 7 of these were hrHPV positive either by RNA ISH or RT-PCR. Two of the p16-negative tumors were positive for lrHPV by RNA ISH. Treatment included surgery alone (4 of 11, 36%), surgery with adjuvant radiation (5 of 11, 45%), and surgery with radiation and chemotherapy (2 of 11, 18%). Four of 11 patients (36%) suffered disease recurrence, two requiring re-operation and who were disease free at last follow-up, one receiving additional chemotherapy and who was alive with disease. The other elected to undergo palliative therapy and died of disease.

CONCLUSION

Sinonasal adenosquamous carcinoma is a somewhat heterogeneous tumor not infrequently arising ex papilloma and having various drivers including high- and low-risk HPV and rarely DEK::AFF2 fusion. The prognosis appears favorable when proper treatment is possible.

Malignant and Nonmalignant Sinonasal Tumors

Sinonasal tumors are rare, diverse, complex lesions with overlapping demographic and clinical features. Malignant tumors are more common, with a grave prognosis, and require biopsy for accurate diagnosis. This article briefly reviews the classification of sinonasal tumors and provides imaging examples and imaging characteristics of each clinically important nasal and paranasal mass lesions. Although there are no true pathognomonic imaging features, it is important for the radiologist to have a broad knowledge of the various CT and MR imaging findings that can help narrow the differential diagnosis and aid in early diagnosis and mapping of tumor for treatment planning.

Low-grade papillary Schneiderian carcinoma with TP53 mutation: a case report and review of the literature

BACKGROUND

Low-grade papillary Schneiderian carcinoma (LGPSC) is a relatively new entity of the sinonasal tract and is characterized by a bland morphology simulating sinonasal papilloma, invasive growth pattern with pushing borders, and aggressive clinical behavior with multiple recurrences and metastatic potential. Recently, DEK::AFF2 fusions were identified in LGPSC. However, some LPGSCs lack DEK::AFF2 fusion, and the molecular features of these tumors have not been clarified.

CASE PRESENTATION

A 69-year-old man presented with a discharge of pus from his left cheek. Computed tomography revealed a mass involving the left maxillary sinus, ethmoid sinus, and nasal cavity with the destruction of the orbital wall. The biopsy specimens showed that the tumor had a predominantly exophytic, papillary growth and did not have an apparent stromal invasion. The tumor was composed of multilayered epithelium that showed bland morphology with a round to polygonal shape, abundant eosinophilic cytoplasm, and uniform nuclei. Dense neutrophilic infiltrates were focally present. Immunohistochemically, CK5/6 was strongly and diffusely positive, and p16 was negative. p63 was mainly positive in the basal layer, and EMA was predominantly expressed in the outermost cell layer. DNA-based targeted sequencing showed TP53 R175H mutation, whereas neither EGFR nor KRAS mutation was identified. Reverse transcription polymerase chain reaction and fluorescence in situ hybridization revealed no DEK::AFF2 fusion.

CONCLUSIONS

We describe the first case of TP53-mutant LGPSC and review the literature. LGPSC is a genetically heterogeneous entity, and the recognition of this rare entity and comprehensive assessment of clinicopathological and molecular findings are crucial for the correct pathological diagnosis and clinical management.

CD163 Immunohistochemical "Circle Sign" Staining Pattern Differentiates Sinonasal Papillomas From Morphologically Similar Non-neoplastic Lesions

Sinonasal papillomas are a diverse group of benign epithelial neoplasms of the sinonasal tract. Inverted papilloma, in particular, must be distinguished from other lesions with no malignant potential. The aim of this study was to distinguish sinonasal papillomas from morphologically similar lesions using CD163 immunostaining. Cases from a 19-year period were identified. These included 49 inverted, 10 exophytic, and 12 oncocytic papillomas, 21 chronic sinusitides with squamous metaplasia, 27 inflammatory polyps, 5 verrucae vulgares, 5 respiratory epithelial adenomatoid hamartomas, and 6 DEK::AFF2 carcinomas of the sinonasal tract. A subset of biopsy cases (8 inverted papillomas, 5 inflammatory polyps) was separately analyzed. CD163 immunohistochemistry (IHC) was performed. A unique "circle" staining pattern was identified in the surface epithelium. After locating a hotspot, circles were quantified in 10 consecutive high-power fields. Circles were present in 66/71 (93%) cases of sinonasal papilloma, with a mean of 35 circles/10 HPF (range: 0 to 160/10 HPF) and a median of 19 circles/10 HPF. Circles were present in 20/58 (34%) non-neoplastic cases, with a mean of 2 circles/10 HPF (range: 0 to 27/10 HPF) and a median of 0. Considering all resection and biopsy cases, performance for distinguishing papillomas from non-neoplastic lesions was best at a cutoff of 10 circles/10 HPF (2-tailed P <0.0001) with sensitivity, specificity, positive predictive value, and negative predictive value of 66.2%, 93.1%, 92.1%, and 69.2%, respectively. The results were similar in the biopsy subset. One other neoplastic entity, the DEK::AFF2 carcinomas, also showed prominent CD163 circle staining. In summary, sinonasal papillomas demonstrate extensive CD163 "circle" staining in the epithelium compared with the non-neoplastic lesions studied. As such, the "circle sign" on CD163 IHC may be helpful in distinguishing between diagnoses, particularly on small biopsies or equivocal specimens.

Nuclear expression of AFF2 C-terminus is a sensitive and specific ancillary marker for DEK::AFF2 carcinoma of the sinonasal tract

DEK::AFF2 carcinoma of the sinonasal tract is an emerging entity. The tumor is typically characterized by papillary proliferation of non-keratinizing squamous epithelial cells with monotonous cytologic features, which may mimic other sinonasal tumors. The confirmation of this gene fusion has thus far relied solely on next-generation sequencing, fluorescence in situ hybridization (FISH), or reverse transcription polymerase chain reaction (RT-PCR). This current study aimed to validate an immunohistochemical assay for AFF2 C-terminus as an ancillary marker. We first analyzed publicly available RNA sequencing data of sinonasal tumors from the national center for biotechnology information (NCBI) sequence read archive and identified 3 DEK::AFF2 carcinomas out of 28 sinonasal tumors. The gene expression of AFF2 was significantly higher in the fusion-positive cases compared to the wild-type tumors (p < 0.001), while DEK was not. We then optimized an immunohistochemical assay with an anti-AFF2 C-terminus antibody for ancillary diagnosis. Seventeen DEK::AFF2 carcinomas, including 11 cases with predominantly low-grade morphology and one showing glandular differentiation, as well as 78 DEK FISH-negative sinonasal tumors were evaluated by AFF2 immunohistochemistry (IHC). Sixteen of the 17 DEK::AFF2 carcinomas showed nuclear AFF2 expression in ≥30% of tumor cells, including one decalcified case that failed FISH and RT-PCR confirmation. The one case that was negative for AFF2 IHC in the tumor cells also lacked expression in the internal positive control. It was thus considered a failure of the IHC rather than a truly negative case and was excluded from the statistical analysis. All DEK FISH-negative sinonasal tumors were negative for nuclear AFF2 expression. The nuclear expression of AFF2 IHC showed 100% sensitivity and specificity for DEK::AFF2 carcinoma. Accordingly, AFF2 IHC is a highly sensitive and specific ancillary marker that distinguishes DEK-AFF2 carcinoma from the other sinonasal tumors with overlapping morphological features and may be an especially useful alternative for decalcified specimens.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Factors Associated with Dysplastic Changes in Sinonasal Inverted Papilloma: Study of Tumor Infiltrating Lymphocytes (TILs) FOXP3, CD4, CD8, and expression of p53

OBJECTIVE

This study examine FOXP3, CD4, CD8 and p53 expression in the transformation of the Sinonasal Inverted Papilloma (SIP) malignancy into sinonasal carcinoma.

MATERIALS AND METHODS

This study used a cross-sectional approach. The research sample from thirty-six paraffin block preparations with the diagnosis of SIP. Then, immunohistochemical staining was performed using FOXP3 mouse monoclonal antibody (236A/E7), CD8 rabbit monoclonal antibody (CD8/1179R), CD4 mouse monoclonal antibody (4B12) and p53 rabbit monoclonal antibody.  Results: There was a significant difference between Foxp3 expression in SIP without dysplasia and SIP with dysplasia (p= 0.013). There was no significant difference between the expression of CD4 and CD8 in the two groups with p-values 0.1 and 0.062, respectively. The mean percentage of positive p53 expression in SIP without dysplasia was 0.45+0.63 and in the SIP with dysplasia 29.31+38.96. There was a significant difference between the two groups (p<0.001).

CONCLUSION

FOXP3 and p53 were overexpressed in SIP with malignant transformation. FOXP3 together with p53 status is associated with dysplastic changed in the SIP. FOXP3 and p53 status could be potential biomarker of malignant transformation in sinonasal inverted papilloma.

Human Papillomavirus-Related Carcinomas of the Sinonasal Tract

Purpose of review

The sinonasal tract is home to a uniquely heterogenous collection of malignant tumors. Human papillomavirus (HPV) has been detected in a number of these, but the virus' role as an oncogenic driver or coincidental finding remains unclear. We aim to highlight five sinonasal tumor types and synthesize the prevalence, etiologic role, and known clinicopathologic relevance of HPV in each.

Recent findings

The last decade has seen an expansion of investigation into HPV's oncogenic and prognostic significance within sinonasal malignancies. The sinonasal tract poses challenges to HPV detection where p16 lacks value as an accurate surrogate. A growing body of data supports a potentially favorable clinical profile for certain sinonasal HPV-positive lesions.

Summary

HPV represents a potential biologically and clinically relevant factor for some sinonasal malignancies. Definitive conclusions regarding HPV's role as a potential oncogenic agent require routine testing using validated methodologies, genomic interrogation, and large-scale prospective studies.

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.

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

Simple Summary

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

Abstract

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

Update from the 5th Edition of the World Health Organization Classification of Head and Neck Tumors: Nasal Cavity, Paranasal Sinuses and Skull Base

The World Health Organization Classification of Head and Neck Tumours recently published the 5th edition. There are new entities, emerging entities, and significant updates to the taxonomy and characterization of tumor and tumor-like lesions, specifically in this article as it relates to nasal cavity, paranasal sinuses and skull base. Importantly, the number of diagnostic entries has been reduced by creating category-specific chapters for soft tissue, hematolymphoid, melanocytic, neuroectodermal, and metastatic tumors. Bone and salivary gland tumors are also not separately reported in the sinonasal tract, but included in the jaw and salivary gland sections, respectively. Repetition of characteristic entities in each anatomic site was also reduced, instead highlighting only the unique features in each anatomic site. Two new entities (SWI/SNF complex-deficient sinonasal carcinomas and HPV-related multiphenotypic sinonasal carcinoma) will be highlighted in this review, with a discussion of several emerging entities. There is a short description of updated information for all 24 diagnostic entities included in this edition to allow the reader a snapshot of current state of knowledge, but to encourage more investigation and further broaden understanding of these diverse and rare entities.

EGFR Exon 20 Insertion Mutations in Sinonasal Squamous Cell Carcinoma

Recurrent epidermal growth factor receptor (EGFR)-activating mutations have been identified in a rare form of head and neck cancer known as sinonasal squamous cell carcinoma (SNSCC), a malignant disease with a 5-year mortality rate of ~40%. Interestingly, the majority of EGFR mutations identified in patients with primary SNSCC are exon 20 insertions (Ex20ins), which is in contrast to non-small-cell lung cancer (NSCLC), where the EGFR exon 19 deletion and L858R mutations predominate. These studies demonstrate that EGFR Ex20ins mutations are not exclusive to lung cancer as previously believed, but are also involved in driving SNSCC pathogenesis. Here we review the landscape of EGFR mutations in SNSCC, with a particular focus on SNSCC associated with inverted sinonasal papilloma (ISP), a benign epithelial neoplasm. Taking lessons from NSCLC, we also discuss potential new treatment options for ISP-associated SNSCC harbouring EGFR Ex20ins in the context of targeted therapies, drug resistance and precision cancer medicine. Moving forward, further basic and translational work is needed to delineate the biology of EGFR Ex20ins in SNSCC in order to develop more effective treatments for patients with this rare disease.

Oro- and Nasopharyngeal Papillomas with Squamous and Respiratory Features: A Case Series of Schneiderian-Like Papillomas of the Pharynx

There is limited literature detailing the histology of pharyngeal papillomas. Herein, we report our experience with papillomas occurring in the oro-and nasopharynx that have both squamous and respiratory features akin to the sinonasal Schneiderian papilloma. We retrospectively reviewed pharyngeal papillomas that were composed of both squamous and respiratory epithelium received at our institution between 2010 and 2020. Cases of sinonasal papillomas directly extending into the pharynx were excluded. Immunohistochemistry for p16 as well as RNA in situ hybridization to evaluate for 6 low-risk and 18 high-risk HPV genotypes were performed on all cases. Thirteen cases were included. Mean age was 61 with 12 males and 1 female. While often incidentally found, presenting symptoms included globus sensation, hemoptysis, and hoarseness of voice. Histologically, all tumors consisted of squamous and respiratory epithelium with neutrophilic infiltrates arranged in an exophytic/papillary architecture that was reminiscent of the exophytic type of Schneiderian papilloma. Immunohistochemistry for p16 was negative in all papillomas. 85% were positive for low-risk human papillomavirus (HPV) subtypes and all were negative for high-risk HPV subtypes. A well-differentiated, invasive squamous cell carcinoma was associated with two of the cases. Papillomas with squamous and respiratory features similar to the sinonasal exophytic Schneiderian papilloma can arise in the oro- and nasopharynx and like their sinonasal counterparts show an association with HPV. While many in this series were benign, they can be harbingers for invasive squamous cell carcinoma.

A Short-Term Efficacy of Anlotinib in the Treatment of Refractory Nasopharyngeal Inverted Papilloma: A Case Report

To our knowledge, no studies have reported the use of anlotinib in the treatment of locally cancerous nasopharyngeal inverted papillomas that cannot be operated on or treated with radiotherapy. Here, we report a case of a 53-year-old woman diagnosed with recurrent local canceration of nasopharynx papilloma. Magnetic resonance imaging (MRI) showed that the right parapharyngeal space, nasopharynx, and ethmoid sinus were changed, and recurrence was considered. There was no indication for surgery or radiotherapy. Imaging showed that the tumor had obvious enhancement and abundant blood vessels. Immunohistochemistry showed that vascular endothelial growth factor receptor (VEGFR) 2 expression was positive in papilloma tissue and in local canceration tissue of the papilloma. After the patient’s consent was obtained, anlotinib treatment was started in May and ended in November 2019. Then, the patient was treated with intensity-modulated radiotherapy (IMRT) with planning gross tumor volume (PGTV) 66 Gy, planning clinical tumor volume 1 (PCTV1) 60 Gy, and planning clinical tumor volume 2 (PCTV2) 54 Gy in 33 fractions. No disease recurrence was reported at 4 months after radiotherapy.

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.

Middle Ear and Temporal Bone Papilloma: A Clinicopathologic Study and Comprehensive Literature Review of 57 Cases

Sinonasal papilloma (SP), formerly Schneiderian papilloma, represents a rare group of benign epithelial neoplasms, most commonly identified in the sinonasal tract, while less frequently identified in the pharynx, lacrimal sac, and middle ear. Within temporal bone sinonasal-type papilloma (TBSP), there seems to be a much higher recurrence and malignant transformation risk than those identified in the sinonasal tract. Based on this clinical report and a review of the cases reported in the English literature, 49% of the 57 cases developed in the setting of concurrent or antecedent sinonasal or nasopharyngeal SP. There is an equal sex distribution (26 females and 31 males), with a broad age range (19-81 years) at presentation (median 56 years; average 54 years). Three patients had bilateral disease. Symptoms include a mass lesion with hearing loss, otitis media, otorrhea, otalgia, and tinnitus, among others. Inverted SP was identified in 42 patients, oncocytic SP in six, and exophytic SP in four (undefined in the remainder). Recurrence was identified in 38 of 49 patients with follow-up (78%), often with multiple recurrences over time, with carcinoma developing in the temporal bone in 19 patients (33%), with males developing carcinoma by a 1.7:1 ratio over females. Surgery was the treatment of choice (radical mastoidectomy) with 6 patients (10%) dead of disease (median 30 months, mean 38 months), while 47 patients were alive at last follow-up: 31 without disease (mean 33 months); 7 with locally recurrent disease (mean 20 months); 9 patients alive but with unknown disease status; and 4 patients without follow-up. In conclusion, TBSP is frequently identified in the setting of concurrent sinonasal tract disease, showing similar histologic features to sinonasal tract counterparts. There is no sex predilection, with patients most commonly presenting in the sixth decade of life. Recurrences are common, with carcinoma developing much more frequently than in sinonasal tract papilloma (33%), but recognizing that carcinoma may be documented in either or both anatomic sites. Overall outcome is excellent, with long term clinical follow-up warranted to manage recurrence or malignant transformation.

Survival Outcomes of De Novo vs Inverted Papilloma-Associated Sinonasal Squamous Cell Carcinoma: A Systematic Review and Meta-analysis

Importance

Overall, the prognosis of sinonasal squamous cell carcinoma (SCC) is poor. This malignancy can arise de novo or from inverted papillomas, but it is unclear whether survival differences between the 2 pathologies exist.

Objective

To assess for survival differences between patients with sinonasal de novo SCC (dnSCC) and those with inverted papilloma-associated SCC (IPSCC).

Data Sources

A search of Ovid MEDLINE, Embase, Scopus, and the Cochrane Library from inception to January 23, 2020, with cross-referencing of retrieved studies, was performed. Additional data were requested from authors.

Study Selection

Inclusion and exclusion criteria were designed to capture studies with survival outcomes of adults with sinonasal SCC who underwent regular treatment. Clinical trials, cohort studies, case-control studies, and case series with more than 10 adults aged 18 years or older with sinonasal SCC were included. Exclusion criteria were studies on non-SCC sinonasal neoplasms, studies without histopathologic diagnoses, non-English language articles, nonhuman animal studies, and abstract-only articles. Two blinded investigators (J.J.L., A.M.P., T.W.E., or N.S.W.) screened each abstract and full text, and a third investigator (J.J.L. or P.P.) adjudicated discrepancies. Of 729 unique citations, 26 studies of 1194 total patients were included.

Data Extraction and Synthesis

Meta-Analysis of Observational Studies in Epidemiology (MOOSE) guidelines were followed. The Methodological Index for Nonrandomized Studies (MINORS) criteria were used to assess study quality. Two blinded investigators (J.J.L., A.M.P., T.W.E., or N.S.W.) independently extracted data from each study. Data were pooled using a random-effects model.

Main Outcomes and Measures

The primary outcome was overall survival, and secondary outcomes were disease-free and disease-specific survival. Before data collection, it was hypothesized that the dnSCC cohort would have worse survival outcomes than the IPSCC cohort.

Results

One study of patients with dnSCC, 12 studies of patients with IPSCC, and 5 studies with both cohorts were included in the meta-analysis of overall survival. The pooled 5-year overall survival rate for 255 patients with dnSCC was 56% (95% CI, 41%-71%; I2 = 83.8%) and for 475 patients with IPSCC was 65% (95% CI, 56%-73%; I2 = 75.7%). Five comparative studies of both cohorts totaling 240 patients with dnSCC and 155 patients with IPSCC were included in another meta-analysis. The pooled overall survival hazard ratio was 1.87 (95% CI, 1.24-2.84; I2 = 0%).

Conclusions and Relevance

This systematic review and meta-analysis found that patients with dnSCC had almost a 2-fold increased risk of mortality compared with those with IPSCC. Large, multicenter studies are necessary to validate these findings before considering treatment alterations such as de-escalation based on histopathology.

Rare Diseases of the Nose, the Paranasal Sinuses, and the Anterior Skull Base

Due to their low incidence and thus resulting limited diagnostic criteria as well as therapeutic options, rare diseases of the nose, the paranasal sinuses, and the anterior skull base are a significant challenge. The value as of which a disease has to be considered as rare amounts to a maximum of 5 patients per 10 000 people. Within these diseases, however, there are extreme differences. Some rare or orphan diseases like for example the inverted papilloma belong to regularly diagnosed and treated diseases of larger departments of oto-rhino-laryngology whereas other rare diseases and malformations have only been described in less than 100 case reports worldwide. This fact emphasizes the necessity of bundling the available experience of diagnostics and therapy. The present article gives an overview about rare diseases of the nose, the paranasal sinuses, and the anterior skull base from the field of diseases/syndromes of the olfactory system, malformations of the nose and paranasal sinuses, ventilation and functional disorders as well as benign and malignant tumors. The classification and data on diagnostic and therapeutic options were established based on the current literature.

Treatment outcome and pattern of recurrence of sinonasal squamous cell carcinoma with EGFR-mutation and human papillomavirus

The objective of our study was to clarify the clinical features of EGFR-mutated sinonasal squamous cell carcinoma (SNSCC) and human papilloma virus (HPV)-related SNSCC. Patients with SNSCC treated from April 2008 to June 2019 at our institution were retrospectively reviewed. We examined EGFR mutation and HPV status for all patients. Main outcomes were overall survival, recurrence, and outcome of each treatment modality. A total of 85 patients with SNSCC were enrolled in this study. EGFR mutations and HPV DNA were detected in 24 (28%) and 7 (8%) patients, respectively. Patients with EGFR-mutated SNSCC showed a worse overall survival (OS) than those with EGFR wild-type in the multivariate analysis (p = 0.037). No death was observed in HPV-positive SNSCC. The cumulative incidence of local recurrence was significantly higher in EGFR mutant than EGFR wild-type tumors (p = 0.03). In patients with EGFR mutations, treatment with induction chemotherapy significantly improved OS (p = 0.01). EGFR-mutated SNSCC have a high-risk feature for recurrence and requires intensive attention for treatment and observation. A new treatment approach, such as EGFR tyrosine kinase inhibitors, may be needed.

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.

Clinicopathologic Significance of EGFR Mutation and HPV Infection in Sinonasal Squamous Cell Carcinoma

Sinonasal squamous cell carcinoma (SNSCC) is sometimes associated with high-risk human papillomavirus (HR-HPV) infection and inverted sinonasal papilloma or oncocytic sinonasal papilloma. Frequent mutations of EGFR and KRAS are reported in inverted sinonasal papilloma-related sinonasal squamous cell carcinoma (ISP-SCC) and oncocytic sinonasal papilloma-related SNSCC, respectively. Here, we attempted to determine the prevalence and the prognostic significances of these alterations in SNSCC. We retrospectively collected 146 SNSCCs, including 14 ISP-SCCs, and comprehensively analyzed the HR-HPV infection by human papillomavirus (HPV)-RNA in situ hybridization, EGFR gene copy number gain (CNG) by chromogenic in situ hybridization, and gene mutations in EGFR and KRAS by Sanger sequencing. HR-HPV was detected in 11 cases (7.5%), whereas all 14 ISP-SCCs were negative. EGFR mutations were present in 21 (14.7%) of 143 SNSCCs, including 13/14 (92.9%) ISP-SCCs and 8/129 (6.2%) non-ISP-SCCs (P<0.0001). The majority of EGFR mutations were exon 20 insertions, with the remainder composed of deletions and single-nucleotide substitutions in exons 19 and 20. All of 142 SNSCCs harbored no KRAS mutation. EGFR CNG was detected in 41 (28.1%) of 146 SNSCCs; all of them were HPV negative and 3 had EGFR mutations. Collectively, EGFR mutation, EGFR CNG, and HR-HPV were essentially mutually exclusive, and each subgroup had distinct clinicopathologic features. The HPV-negative/EGFR-mutant group, the HPV-negative/EGFR CNG-positive group, and the triple-negative group had significantly worse prognoses than the HPV-positive group (P=0.0265, 0.0264, and 0.0394, respectively). In conclusion, EGFR mutation may play a pathogenetically important role in some populations of SNSCCs, especially ISP-SCCs. The molecular subclassification of SNSCCs may contribute to prognostic prediction and molecular-targeted precision medicine.

Malignant Transformation of Temporal Bone Schneiderian Papilloma Associated with HPV-6

Introduction

Temporal bone Schneiderian papillomas (TBSPs) rarely present as a primary tumors arising from the middle ear and mastoid process. The clinical findings and imaging of TBSPs are not specific. Therefore, diagnosis can only reliably be definitively established by histopathology.

Objective

To report a novel case of a malignant transformation of TBSP associated with HPV-6 and to present its management. Case Report. A 68-year-old woman presented with conductive hearing loss and recurrent right-sided otorrhoea. Initially, we performed a lateral temporal bone resection and obliteration with abdomen fat. Early histology described TBSP associated with HPV-6. Follow-up detected malignant transformation of the Schneiderian papillomatous variant. Postoperative radiotherapy combined with extended temporal bone resection resulted in a disease-free 17-month period of follow-up. Discussion. TBSPs are not very specific, and the diagnosis can only reliably be established by histopathology. There is a risk of malignant transformation, and due to the absence of reliable prognostic markers, strict postoperative follow-up is mandatory and should consist of regular otoscopy, nasal endoscopy, and imaging. This case also supports the importance of extended temporal bone resections as salvage surgery, combining radical surgery with radiotherapy for improved survival rates.

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

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

Malignant Transformation of Schneiderian Papilloma Presenting With Progressive Binocular Diplopia and Blepharoptosis

Sinonasal tumors arising from Schneiderian papillomas, most frequently associated with squamous cell carcinoma (SCC), are rare and often present with non-specific symptoms, even in an advanced stage. Herein, we report the case of a 61-year-old male who presented with a four-month history of progressive binocular diplopia, blepharoptosis, and amblyopia, and upon the essential diagnostic work-up he was subsequently diagnosed with SCC arising from an SP. Surgical management was not warranted due to the extent of the disease, so induction chemotherapy with cisplatin and 5-fluorouracil (5-FU) was commenced, followed by definitive concurrent chemoradiotherapy (CRT). The patient was still alive at 25 months after his first presentation, receiving supportive care. Our case highlights the importance of early recognition of neuro-ophthalmological disorders related to sinonasal carcinomas, as diagnostic delay may lead to both functional complications and higher morbidity.

P16 detection in benign, precursor epithelial lesions and carcinomas of head and neck

BACKGROUND

Human papillomavirus (HPV) had recently been implicated in the pathogenesis of Head and Neck SCCs. The biological role of HPV in benign and pre-cancerous lesions is far less studied. p16 is a widely accepted marker to detect immonohistochemically the presence of HPV.

METHODS

We evaluated, immunohistochemically, expression of p16 in 212 specimens: glottis, supraglottis, oropharynx, nasal/paranasal, with various diagnoses: hyperplasia, polyp/nodule, keratosis, papilloma, inverted papilloma, dysplasia, cancer (SCC). Analysis was completed according to location and disease.

RESULTS

Hyperplasias/polyps were all negative for p16. A small percentage of papillomas was p16+ regardless of their location (12.5 %), the majority of inverted papillomas were p16+ (78.6 %) and statistically significant (p < 0.04). In carcinomas, 18/59 were p16+ (30.5 %): nasal/paranasal SCCs had a significantly higher percentage of p16+ cancer cells compared to glottis (p = 0.009), while tumours of the supraglottis/oropharynx had an intermediate score for p16+ cells (p = 0.07). Dysplasias were p16+ in 9/64 (14 %) regardless of grading (p = 0.03 compared to carcinomas).

CONCLUSION

p16 was highly detected in inverted papillomas and in certain anatomic sites; however, it failed to be traced in benign lesions and only rarely encountered in dysplasias.

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.

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

Background

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

Methods

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

Results

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

Conclusion

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

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.

Frequent KRAS and HRAS mutations in squamous cell papillomas of the head and neck

Squamous cell papilloma (SCP) is a benign neoplasm of the head and neck. Human papillomavirus (HPV) has been reported to be a tumourigenic factor for SCP. However, not all SCPs are positive for HPV, suggesting that other possible mechanisms are involved in their development. In this study, we examined the mutational status of 51 SCPs using targeted panel sequencing in addition to HPV status using GP5+/GP6+ PCR. HPV DNA was detected in 6 (12%) SCPs, while KRAS and HRAS mutations were detected in 18 (35%) and 17 (33%) SCPs, respectively. Notably, KRAS mutations, HRAS mutations and HPV infection were mutually exclusive. The larynx and trachea (4/7, 57%) were more preferentially infected by HPV than the other sites (2/44, 5%, p = 0.0019) and HPV was associated with multifocal development (4/5, 80%). In contrast, KRAS and HRAS mutations in SCPs were evenly distributed across the anatomical sites and found only in single SCPs. In conclusion, this study demonstrated that HPV was not frequently involved in SCPs and that RAS mutations were more common alterations. In contrast to inverted sinonasal papillomas and oncocytic sinonasal papillomas, SCP may not be a precursor lesion of carcinoma, because these aetiological events in SCP are distinct from squamous cell carcinoma in the same sites.

Sinonasal Papillomas and Carcinomas: A Contemporary Update With Review of an Emerging Molecular Classification

Context.—

Sinonasal papillomas and carcinomas are uncommon head and neck neoplasms that comprise a broad clinicopathologic and morphologic spectrum, and thus frequently represent a diagnostic challenge for surgical pathologists. Recent molecular interrogation of these tumors has delineated a number of recurrent alterations that correspond to distinct entities with potential diagnostic and/or therapeutic clinical utility.

Objective.—

To summarize the salient clinicopathologic, morphologic, and molecular features of sinonasal papillomas and carcinomas.

Data Sources.—

Review of pertinent literature regarding sinonasal papillomas and sinonasal carcinomas.

Conclusions.—

Despite their relative rarity in many surgical pathology practices, sinonasal papillomas and carcinomas frequently demonstrate characteristic morphologic features that are important for accurate diagnosis. Given our emerging understanding of the molecular basis for these tumors, judicious use of available ancillary tools—including immunohistochemistry and in situ hybridization—may be helpful in subsets of cases, whereas additional molecular testing may be useful for diagnostically challenging and/or clinically aggressive sinonasal tumors.

Low-Grade Papillary Schneiderian Carcinoma: Report of a Case with Molecular Characterization

In 2015, Lewis et al. first described low-grade papillary Scheneiderian carcinoma (LGPSC) of the sinonasal tract. Their case resembled a sinonasal papilloma clinically and histopathologically; however, invasion and metastasis resulted in the death of the patient despite absence of malignant cytologic features. Additional reports established LGPSC as a distinct entity and characterized its immunohistochemical profile. Diffuse expression of low molecular weight cytokeratins, positivity for p16 and p53 in at least 50% of cells, a high Ki-67 index, and absence of human papillomavirus (HPV)-DNA was observed across all reported cases. We report an additional case of LGPSC and describe the clinical, histologic, and immunohistochemical features. In contrast to sinonasal papillomas, the case was negative for HPV-DNA and showed no mutations in the EGFR and KRAS hotspot regions.

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.

Novel synchronous nasal involvement of inverted papilloma and recurrent respiratory papillomatosis with confirmed human papillomavirus isolated from nasal septum and middle turbinate: a case report

Background

Recurrent respiratory papillomatosis is a chronic disease of viral origin affecting the larynx, trachea, and lower airways. Inverted papilloma, most commonly originating from the lateral nasal wall, is typically a single, expansile, locally aggressive tumor that remodels bone around the site of origin.

Case presentation

We report a case of histopathologically proven inverted papilloma occurring in a 50-year-old Caucasian man with recurrent respiratory papillomatosis affecting his nasal cavity, larynx, and trachea. This constitutes the first report of nasal involvement in recurrent respiratory papillomatosis. Viral in situ hybridization studies demonstrated evidence of human papillomavirus in both the septum and middle turbinate subsites. Repeat nasal excision with margin analysis is planned.

Conclusions

This report emphasizes the importance of considering a broad differential diagnosis in patients with papillomata, and obtaining comprehensive histopathologic evaluation of lesions in multiple subsites in order to rule out inverted papilloma or overt malignant transformation, particularly if high-risk human papillomavirus (HPV) subtypes are identified.

Level of evidence

4

Comparative transcriptome analysis of sinonasal inverted papilloma and associated squamous cell carcinoma: Out-HOXing developmental genes

BACKGROUND

Sinonasal papilloma has a tendency toward local destruction, recurrence, and malignant transformation. This study aimed to unravel mechanisms in the malignant transformation of sinonasal papillomas using RNA-seq.

METHODS

The cohort consisted of 37 consecutive patients; tumor histology included a continuum spectrum (sinonasal papillomas/dysplastic/carcinomas-in-situ/invasive squamous cell carcinomas). These were microdissected and RNA was subjected to whole-transcriptome shotgun sequencing.

RESULTS

RNA-seq and pathway analysis showed that the highest expressed genes/potential drivers were development- and differentiation-related genes. The protein expression of six highly upregulated genes (HOXA9, EN1, DUX4, CA9, CD1a, and CK5/6) validated the RNA-seq results. HOXA9 and CA9 were found to be expressed in most of the carcinoma samples but were largely negative in papillomas; all of the CA9-negative carcinomas were recurrent.

CONCLUSIONS

We conclude that sinonasal carcinomas arising from papillomas are mainly defined by overexpressed developmental/homeobox genes, which provide the potential for transformation/plasticity, along with differentiation and proliferation behavior of neoplastic cells. Our results support HOXA9 and CA9 as biomarkers for carcinomas, with CA9 emerging as a predictive marker of recurrence.

Putative biomarkers of malignant transformation of sinonasal inverted papilloma into squamous cell carcinoma

OBJECTIVE

To compare genome-wide DNA methylation between samples of sinonasal inverted papilloma (SNIP) and squamous cell carcinoma (SCC) samples in order to identify aberrantly methylated genes that might be involved in malignant transformation.

METHODS

Tissue samples were collected from patients. DNA methylation in C-phosphate-G islands and gene promoters was analysed using a DNA methylation microarray kit. The levels of mRNA or protein from aberrantly methylated genes were measured using real-time polymerase chain reaction or Western blot analysis.

RESULTS

A total of 27 tissue samples were included in this study; 15 SNIP samples and 12 SCCs arising in SNIPs. A total of 11 201 nominally differentially methylated sites were observed between SNIP and SCC arising in SNIPs. Six sites were significantly different at P < 0.01 and contained three genes ( MIR661, PLEC and OPA3). These three genes were hypermethylated. In addition, the levels of mature miR-661 mRNA and PLEC protein were significantly upregulated in SCC tissues compared with SNIP samples. The levels of OPA3 protein were downregulated in SCC tissues compared with SNIP samples.

CONCLUSIONS

This study demonstrated hypermethylation and abnormal expression of the MIR661, PLEC and OPA3 genes, suggesting a role for their involvement in the malignant transformation of SNIP.

Inverted papilloma presenting as unilateral proptosis: A case report with review of literature

Inverted papilloma is an interesting benign tumour arising from lining epithelium of paranasal sinuses which most commonly involves nasal cavity and paranasal sinuses. However, involvement of orbit and intracranial extension without malignant transformation is very rare. We report a case of extensive inverted papilloma of frontal sinus which primarily presented with proptosis, an uncommon presentation. Ophthalmologic symptoms are rare manifestations of paranasal sinus inverted papilloma without malignant transformation and signify extensive disease with possible intracranial extension.

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).

Oncocytic Schneiderian papilloma-associated adenocarcinoma and KRAS mutation: A case report

RATIONALE

Oncocytic Schneiderian papillomas (OSP) are an uncommon type of sinonasal papillomas that arise from the Schneiderian epithelium, accounting for only 6% of all sinonasal papillomas. Malignancies arising in OSP are rare and are almost always described as in situ or invasive squamous cell carcinoma, although mucoepidermoid, small cell carcinoma and sinonasal undifferentiated carcinoma have also been reported. To our knowledge, only 18 such instances have been reported in the medical literature.

PATIENT CONCERNS

Here, we report the case of an 81-year-old man presenting with a left sinonasal neoplasm, who had undergone 4 operations. The first postoperative pathology revealed a benign nasal polyp. The following several postoperative pathology revealed a novel, human papillomavirus-negative adenocarcinoma with increasing malignant features with each recurrence arising in an OSP. In addition, the most recent recurrences were associated with metastasis of cervical lymph nodes. And after the operation, the patient refused adjuvant radiotherapy. On 6-month follow-up after the last operation, the patient developed an in situ tumor recurrence 1 month after the fourth operation and refused to undergo surgery again.

DIAGNOSIS

Immunohistochemistry for Ki67, CK7, CK5/6, P53, and P63 showed a progression of malignancy. HPV assay presented the 21 most prevalent HPV types were negative. In addition, KRAS gene exon 2 G12C presented mutation in the OSP-associated adenocarcinoma.

INTERVENTIONS

During the whole course of the patient's disease, we performed four nasal endoscopic operations. And after the last operation, the patient refused adjuvant radiotherapy and KRAS-targeted therapy.

OUTCOMES

We are the first to describe adenocarcinoma arising in an OSP. To our surprise, from the first benign neoplasm to the second OSP-associated adenocarcinoma, it went through a long period of 10 years. However, after the adenocarcinogenesis, the differentiation of tumor became worse with the shorter interval of each recurrence.

LESSONS

Therefore, for elderly patients with unilateral nasal polyps, long-term follow-up is necessary. Once OSP turns into malignant, radical resection should be performed as much as possible to reduce the irritability of tumors.