Quantitative differentiation of non-invasive bladder urothelial carcinoma and inverted papilloma based on CT urography.

PURPOSE: To investigate the value of CT urography (CTU) indicators in the quantitative differential diagnosis of bladder urothelial carcinoma (BUC) and inverted papilloma of the bladder (IPB). MATERIAL AND METHODS: The clinical and preoperative CTU imaging data of continuous 103 patients with histologically confirmed BUC or IPB were retrospectively analyzed. The imaging data included 6 qualitative indicators and 7 quantitative measures. The recorded clinical information and imaging features were subjected to univariate and multivariate logistic regression analysis to find independent risk factors for BUC, and a combined multi-indicator prediction model was constructed, and the prediction model was visualized using nomogram. ROC curve analysis was used to calculate and compare the predictive efficacy of independent risk factors and nomogram. RESULTS: Junction smoothness, maximum longitudinal diameter, tumor-wall interface and arterial reinforcement rate were independent risk factors for distinguishing BUC from IPB. The AUC of the combined model was 0.934 (sensitivity = 0.808, specificity = 0.920, accuracy = 0.835), and its diagnostic efficiency was higher than that of junction smoothness (AUC=0.667, sensitivity = 0.654, specificity = 0.680, accuracy = 0.660), maximum longitudinal diameter (AUC=0.757, sensitivity = 0.833, specificity = 0.604, accuracy = 0.786), tumor-wall interface (AUC=0.888, sensitivity = 0.755, specificity = 0.808, accuracy = 0.816) and Arterial reinforcement rate (AUC=0.786, sensitivity = 0.936, specificity = 0.640, accuracy = 0.864). CONCLUSION: Above qualitative and quantitative indicators based on CTU and the combination of them may be helpful to the differential diagnosis of BUC and IPB, thus better assisting in clinical decision-making. KEY POINTS: 1. Bladder urothelial carcinoma (BUC) and inverted papilloma of the bladder (IPB) exhibit similar clinical symptoms and imaging presentations. 2. The diagnostic value of CT urography (CTU) in distinguishing between BUC and IPB has not been documented. 3. BUC and IPB differ in lesion size, growth pattern and blood supply. 4. The diagnostic efficiency is optimized by integrating multiple independent risk factors into the prediction model.

Global research on sinonasal inverted papilloma over the past two decades: a bibliometric analysis.

Objective: This study aimed to investigate the global research status, hot topics, and prospects in the field of sinonasal inverted papilloma (SNIP) through bibliometric analysis. Methods: The literature on SNIP was retrieved and downloaded from the Web of Science Core Collection from 2002 to 2021. The bibliometric and visualisation networks of SNIP were constructed using VOSviewer 1.6.18, CiteSpace 6.1. R2, and a bibliometric online analysis platform. Results: A total of 560 original articles about SNIP research were included, involving 2,457 authors from 610 institutions in 45 countries. The number of SNIP publications showed an overall rising trend, with an average annual output of 28 articles and almost 3 times as many articles published in 2020 as in 2002. The analysis of keyword burst detection indicated that EGFR mutation, malignant transformation and infection are emerging research hotspots. Moreover, EGFR mutation, KRAS mutation, malignant tumour, metallothionein 2a gene, pre-operative diagnosis, HPV-negative tumour, and expression were among the 11 key clusters of co-cited references. Conclusions: This study provided a comprehensive, systematic, and objective analysis and visualised knowledge map of SNIP over the past 2 decades. In particular, current hotspots and prospective trends in the field of SNIP have been identified. These results highlight the future direction of SNIP research for rhinologists.

Computed Tomography Imaging Patterns of Sinonasal Inverted Papillomas: Comparison of Primary and Recurrent Disease.

OBJECTIVE: To analyze clinical and radiographic features that may impact the rate of focal hyperostosis (FH) on computed tomography (CT) for primary and recurrent sinonasal inverted papillomas (IPs) as well as highlight factors that may affect concordance between FH and IP true attachment point (TAP). METHODS: All IPs resected between 2006 and 2022 were retrospectively reviewed. CTs were read by a neuroradiologist blinded to operative details. IP with malignancy was excluded. Operative reports and long-term follow-up data were evaluated. RESULTS: Of 92 IPs, 60.1% had FH, 25% had no CT bony changes, and 20.7% were revision cases. The recurrence rate for rhinologists was 10.5% overall and 7.3% for primary IPs. Primary and revision IPs had a similar rate of FH (63% vs. 52.6%; p = 0.646) and FH-TAP agreement (71.7% vs. 90%; p = 0.664). Nasal cavity IPs, especially with septal attachment, were more likely to lack bony changes on CT (57.1%) compared to other subsites (p = 0.018). Recurrent tumors were 16 mm larger on average (55 mm vs. 39 mm; p = 0.008). FH (75.0% vs. 60.9%; p = 0.295), FH-TAP concordance (91.7% vs. 74.4%; p = 0.094), and secondary IP (18.8% vs. 20.3%; p = 0.889) rates were similar between recurrent and nonrecurrent tumors. CONCLUSION: Primary and revision IPs have a similar rate of FH and FH-TAP agreement. Nasal cavity IPs are less likely to exhibit bony CT changes. Lower recurrence was associated with smaller size and fellowship training but not multiple TAPs, revision, FH absence, or FH-TAP discordance. LEVEL OF EVIDENCE: 3 Laryngoscope, 134:1591-1596, 2024.

Minimally Anterior Medial Maxillary Approach (MAMMA): a novel technique for a wide access to the maxillary sinus.

PURPOSE: To describe a novel endoscopic technique to approach the maxillary sinus (MS), the Modified Anterior Medial Maxillary Approach (MAMMA), preserving the inferior turbinate (IT) and the nasolacrimal duct (NLD). To perform radiological measurements and describe a case series to study the feasibility and limits of MAMMA. METHODS: Computed tomography (CT) scans (n = 150 nasal cavities) were used to calculate areas of the MAMMA to define surgical limits and extensions. Measurement of distances to critical anatomy landmarks and total area for the MAMMA were calculated. An instructional case illustrating the surgical technique and outcome was also included. RESULTS: Radiological analysis showed a mean distance from the Piriform Aperture (PA) to the anterior limit of the NLD of 1.03 ± 0.18 cm (range 0.59-1.48) and a mean distance from de PA to the posterior limit of the NLD of 1.57 ± 0.22 cm (range 1.02-2.11). The mean distance from the nasal floor to the Hasner's valve was 1.61 ± 0.27 cm (range 1.06-2.52) and the distance from the nasal floor to the insertion of the IT was 2.20 ± 0.36 cm (range 1.70-3.69). Finally, the mean total area for the MAMMA was 4.04 ± 0.52 cm2 (range 3.17-5.53). No complications or recurrence of the pathology were observed in operated patients. CONCLUSION: The MAMMA provides a wide surgical field of the MS walls comparable to more aggressive techniques, with preservation of the sinonasal and lacrimal function. MAMMA is an effective alternative to treat different MS pathologies including benign recurrent maxillary sinus tumors.

RAS Family Gene Mutations, Clinicopathological Features, and Spread Patterns of Inverted Urothelial Papilloma of the Bladder.

Inverted urothelial papilloma (IUP) is a benign neoplasm characterized by a downgrowth of the urothelium beneath the surface of morphologically normal urothelial cells; however, the molecular features of IUP and their association with clinicopathological characteristics are unclear. In this study, we aimed to investigate the mutational landscape, clinicopathological features, genotype-phenotype associations, and spread patterns of IUP. We performed targeted next-generation sequencing of 39 consecutive IUP cases, the largest series investigated to date, and identified oncogenic driver mutations in RAS family genes in 34 cases (87%). HRAS mutations were the most prevalent (28 cases), which included Q61R (15 cases), followed by KRAS (5 cases) and NRAS (1 case) mutations. Characteristic mutations observed in urothelial carcinoma, including those in FGFR3 , TP53 , or the TERT promoter, were absent. HRAS -mutated IUPs were associated with a history of smoking ( P = 0.017) and streaming morphology ( P < 0.001), corresponding to the trabecular subtype. In contrast, all KRAS -mutated IUPs occurred in never-smoking patients ( P = 0.001) and showed cystic changes in morphology ( P = 0.005), corresponding to the glandular subtype. RAS Q61R immunohistochemistry visually revealed the neoplastic nature of the overlying cells and distinct spread patterns of IUP cells within the surface, including pseudoinfiltrative spread. No recurrence or carcinoma development was observed in any of the IUP cases during the follow-up period. Thus, we confirmed the importance of RAS pathway activation in IUP pathogenesis, an association between RAS family gene mutations and IUP subtypes, and the spread patterns of IUP cells within the surface.

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.

An in vitro model and the underlying pathways of sinonasal inverted papilloma development.

Recently, the specific association between Sinonasal inverted papilloma (SIP) and EGFR exon 20 mutations has been reported. To investigate the link between specific EGFR mutations and SIP development, we established organotypic raft culture system using nasal polyp-derived immortalized NP2 (iNP2) cells expressing EGFR exon 20 mutants or an exon 19 mutant, and SIP-derived iIP4 cells harboring P772_H773insPYNP mutation. In the raft culture, iIP4 cells showed the inverted growth pattern characteristic to SIP. Interestingly, iNP2 cells expressing EGFR exon 20 duplication mutants, S768_D770dup and N771_H773dup, but not of EGFR exon 19 mutant, E746_A750del, showed the inverted growth pattern. Enhanced activation of the PI3K/AKT signaling pathway was observed in iNP2_S768_D770dup and iIP4 cells, while increased MAPK signaling was found in iNP2_N771_H773dup. Increased cell migration and invasion were found in all cells carrying EGFR mutations when compared to iNP2 cells, and this effect was inhibited by either PI3K or MEK inhibitor. Notably, iNP2 cells expressing the N771_H773dup mutant showed the highest migration and invasion abilities. These results suggest that specific mutations in EGFR exon 20 play a crucial role in SIP development, partially though hyper-activation of the PI3K/AKT and MAPK signaling pathways. This study presents the first in vitro model for SIP development, which could facilitate further investigations into SIP pathogenesis and preclinical studies for new therapeutic agents.

Extended sphenoidotomy combined with transpterygoid approach for sphenoidal sinus inverted papilloma.

PURPOSE: Inverted papilloma of the sphenoid sinus (IPSS) is a rare tumor with debated surgical management due to its proximity to vital structures. The aim of this manuscript is to highlight the role of a transpterygoid approach (TPA) and pedicle-orientated strategy in case of involvement of critical structures in IPSS and compare it with data from the literature. METHODS: Patients with primary IPSS between January 2000 and June 2021 were included. Pre-operative CT/MRI were analyzed to classify the pneumatization of the SS and predict the insertion point of the inverted papilloma. All patients were treated with a trans-sphenoidal approach which was combined with a TPA in case of lateral insertion point. A systematic search was also performed to summarize the available literature. RESULTS: Twenty-two patients were treated for IPSS. By CT, the SS was categorized with type III pneumatization in 72.8% of cases. Eleven patients (50%) were treated with a TPA with a statistical association with the insertion point on the SS lateral wall (p = 0.01), rather than a SS pneumatization (p = 0.63). The overall success was 95.5% after a mean follow-up of 35.9 months. For the literature, 26 publications were included on 97 patients and described a trans-sphenoidal approach with a success rate of 84.6% after a mean follow-up of 24.5 months. CONCLUSION: IPSS is generally treated with a sphenoidotomy approach, although in selected cases, a TPA should be preferred to expose the whole SS lateral wall though allowing a complete pedicled oriented resection of the tumor.

Validation of modular endoscopic medial maxillectomies for inverted papilloma of the maxillary sinus.

BACKGROUND: Treatment of inverted papilloma of the maxillary sinus (IPMS) has a lower success rate compared to other IPs. As such, its correct management generally needs trans-nasal endoscopic medial maxillectomy (EMMs) for adequate resection. The aim of this manuscript is to describe outcomes and major prognostic factors of a cohort of patients with IPMS who were treated with EMM. METHODOLOGY: In this multicentric study, patients affected with IPMS and treated with EMMs were included. The site of origin of the IPMS were studied as well as the type of EMM performed. The histological features (IP vs dysplasia), type of mucosal resection (total vs. pedicle oriented), and post-operative complications were analyzed. RESULTS: 310 patients were included (212 primary and 98 recurrent cases). After a mean follow-up of 45.4 months, 15 patients experienced recurrence (4.8%) due to the application of EMMs tailored to the surgical insertion point. Dysplasia was significantly associated with a higher risk of recurrence. The rates of early and late complications were 11.6% and 11.9%, respectively. CONCLUSIONS: IPMS resection via tailored EMM is associated with excellent disease control, thus excluding the systematic use of extended EMMs, which can however be justified in case of dysplastic IPMS given its significant impact on recurrence.

The implications of concomitant mucosal inflammation on clinical manifestations and outcomes of sinonasal inverted papilloma.

PURPOSE: This study examines the impact of concomitant mucosal inflammation on clinical manifestations and long-term outcomes of Inverted Papilloma (IP). METHODS: This retrospective cohort study was conducted in five tertiary medical centers. The included patients underwent an attachment-oriented surgical resection for IP with a minimum follow-up of 3 years. RESULTS: Of 185 patients with IP, 65 patients (35.1%) had synchronous mucosal inflammation with polypoid changes. The mean age was 56.7 years, and 69% were males. Most tumors originated from the maxillary sinus. Age, gender, Krouse stage, and tumor attachment site did not differ between the mucosal inflammation and IP-only groups. IP recurrence rate was twofold in the patients with mucosal inflammation (15.4% vs. 7.5%, p = 0.092). However, the difference was not significant, with a similar median time to recurrence between the two groups [15.5 (3-36) months vs. 16(6-96) months, p = 0.712]. In revision cases, IP recurred only in patients with mucosal inflammation (19% vs. 0%, p = 0.07). This group had a significantly worse 5-years recurrence-free survival than revision cases without mucosal inflammation (80.6% vs. 100%, p = 0.04). CONCLUSIONS: IP in the setting of mucosal inflammation might be associated with a higher recurrence rate, predominantly after revision surgery. Otolaryngologists should consider this during these patients' diagnosis, surgical planning, and follow-up.

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.

[Application experience of prelacrimal recess combined with septotomy in resection of recurrent inverted papilloma].

Objective:To investigate the effectiveness of nasal endoscopic anterior lacrimal recess approach combined with temporary fenestration of the nasal septum in resecting recurrent nasal inverted papilloma. Methods:Patients with recurrent nasal inverted papilloma who underwent reoperation in our hospital during the past 2 years were included . The nasal septum may hinder full access to and effective treatment of the lesions at the anterior and medial wall of the maxillary sinus by endoscope, aspirator and surgical instrument in the narrow aperture of the prelacrimal recess, although these lesions could be observed by 70° nasal endoscope. Results:The nasal septum is temporarily opened on the basis of the prelacrimal recess approach, and the nasal endoscope and instrument was introduced through trans-septal window, so as to provide a better view of the operative field and the angular range of the instrument's movement. Conclusion:The recurrent nasal inverted papilloma could be successfully managed by re-endoscopic anterior lacrimal recess approach combined with temporary fenestration of the nasal septum, and no recurrence was observed during the 2-year follow-up. This surgical approach is recommended for the inverted papilla which originates from the anterior medial wall of the maxillary sinus, as the tumor can be removed completely using this surgical approach.

Evaluation of inverted papilloma recurrence rates and factors associated recurrence after endoscopic surgical resection: a retrospective review.

BACKGROUND: Sinonasal inverted papillomas (IP) are benign tumours arising from the mucosal lining of the nasal cavity and paranasal sinuses with a high propensity for recurrence and malignant transformation. Advances in endoscopic surgery and improved radiologic navigation have increased the role of endoscopic surgical resection in the treatment of IPs. The current study aims to evaluate the rate of IP recurrence after endoscopic endonasal resection and to evaluate factors which impact recurrence. METHODS: This was a single-centre retrospective chart review of all patients who underwent endoscopic sinus surgery for management of IP between January 2009 and February 2022. Primary outcomes were the rate of IP recurrence and time to IP recurrence. Secondary outcome measures were patient and tumour factors that contributed to IP recurrence. RESULTS: Eighty-five patients were included. The mean age was 55.7 and 36.5% of patients were female. The mean follow-up time was 39.5 months. Of the 85 cases, 13 cases (15.3%) had recurrence of their IP and the median time to recurrence was 22.0 months. All recurrent tumours recurred at the attachment site of the primary tumour. The univariate analysis did not identify any significant demographic, clinical, or surgical predictors of IP recurrence. There were no significant changes in sinonasal symptoms at the time IP recurrence was detected. CONCLUSION: Endoscopic endonasal resection of IPs represents an effective surgical approach, however, the relatively high rate of recurrence and lack of symptomatic changes at the time of recurrence necessitates long term follow up. Better delineation of risk factors for recurrence can help identify high-risk patients and inform postoperative follow up strategies.

The choice of endoscopic surgical approach and four steps of operation of inverted papilloma of the maxillary sinus.

OBJECTIVE: The aim of this study was to determine the long-term efficacy of four steps of operation on the treatment of maxillary sinus (MS) inverted papilloma (IP). METHODS: 83 patients who were diagnosed with IP that originated from the MS, underwent four step procedure of attachment sites, including mucosal stripping, periosteum ablation, bone drilling and bone ablation and had postoperative follow-up of 3 years were enrolled. RESULTS: Of the 83 patients, 59 (71.1%) patients were primary surgery and revision surgery in 24 (28.9%), single attachment was in 31(37.3%) patients and multifocal attachments in 52 (62.7%).When the numbers were not mutually exclusive, the most common origin sites of IPs were the medial wall in 54 (37.2%), lateral wall in 29 (20.0%), anterior wall in 18 (12.4%), inferior wall in 22 (15.2%), posterior in 15 (10.3%), and superior wall in 7 (4.8%). Large MMA alone was performed in 5 (6.0%), MMA combined with medial maxillectomy 76 (91.6%), and MMA combined with Caldwell-Luc approach in 2 (2.4%). No major intra- or postoperative complications were observed. The average follow-up was 41 months (range, 37-61 months). CT and endoscope showed that tumor and symptom recurrence occurred in 2 patients (2.41%). In addition, although the opening of antrostomy was closed and CT revealed the uniform soft tissue shadow and hyperostosis of MS in 11(13.3%) patients, they didn't report any symptoms and showed well epithelization of middle meatus mucosa. CONCLUSION: The four steps of operations of attachment sites of MS IP, including mucosal stripping, periosteum ablation, bone drilling and bone ablation, may effectively prevent the recurrence of MS IP.

Endonasal Lacrimal Transposition to Expand Pre-Lacrimal Medial Maxillectomy Approach.

EPLA lacrimal transposition facilitates management of maxillary sinus/pterygopalatine fossa lesions and overcomes limitations such as the Simmen type I recess or IPMS pedicled on the medial wall, without increasing peri-operative morbidity. Laryngoscope, 133:2090-2094, 2023.

Predictive Value of Magnetic Resonance Imaging Multi-parametric Analysis for Malignant Transformation of Sinonasal Inverted Papilloma: A Comprehensive Prediction Model.

OBJECTIVE: Accurate preoperative prediction of sinonasal inverted papilloma (SNIP) malignant transformation is essential and challenging. In this study, 3.0T magnetic resonance was used for qualitative, quantitative, and multi-parametric analysis to evaluate the predictive value of magnetic resonance imaging (MRI) in malignant transformation. METHODS: The data of patients with SNIP (n=83) or SNIP-transformed squamous cell carcinoma (SNIP-SCC) (n=21) were analysed retrospectively. Univariate analysis and multivariate logistic regression were used to establish models to predict the risk factors for the malignant transformation of SNIP. Receiver operating characteristic (ROC) curves were used to evaluate the ability of independent risk factors and related combination models to predict the malignant transformation of SNIP. RESULTS: Convoluted cerebriform pattern (CCP) mutation, apparent diffusion coefficient ratio (ADCr), and wash-in index (WII) 2 and 3 were independent risk factors for predicting malignant transformation of SNIP, with area under the ROC curve (AUC) values of 0.845, 0.862, 0.727, and 0.704, respectively. The AUC of the quantitative parameter model combined with ADCr and WII 2 and 3 was 0.910 for diagnosing malignant transformation. The AUC of the comprehensive model comprising all independent risk factors was 0.937, with a sensitivity, specificity, and accuracy of 90.48%, 90.36%, and 92.31%, respectively. CONCLUSION: Compared with assessing independent risk factors of CCP mutation, ADCr and WII, and the quantitative parameter model, the comprehensive model could improve the differential diagnosis ability of SNIP and SNIP-SCC, which provides an important imaging basis for the possible accurate preoperative evaluation of the malignant transformation of SNIP.

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

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

Sinonasal inverted papilloma - malignant transformation and non-sinonasal malignancies.

OBJECTIVES: To assess malignant transformation rate, non-sinonasal malignancies, and factors contributing to recurrence in patients treated for sinonasal inverted papilloma (SNIP). STUDY DESIGN: Retrospective study. METHODS: We retrospectively reviewed medical records of all patients treated for SNIP (n = 296) between the years 1984-2014 at Helsinki University Hospital. Data from the Finnish Cancer Registry confirmed the number of those patients with sinonasal and non-sinonasal malignancies. RESULTS: Only 2 of 296 (0.7%) patients primarily diagnosed with benign SNIP developed sinonasal cancer in a mean follow-up of 5.8 years. The most common non-sinonasal cancer sites were similar to those reported for the whole Finnish population. None of the patients presented with an HPV-associated non-sinonasal malignancy. The recurrence rate among patients who underwent attachment-oriented surgery was significantly lower compared to those operated on with other approaches (40.2% vs. 56.6%, p = 0.006). Dysplasia in SNIP was associated with a higher recurrence rate (p < 0.001). CONCLUSIONS: Malignant transformation of SNIP was rare. Patients with SNIP were not prone to HPV-associated non-sinonasal malignancies. Endoscopic resection and attachment-oriented surgery have become predominant approaches in the treatment of SNIP; meanwhile, the total number of SNIP recurrences has decreased. LEVEL OF EVIDENCE: 3 Laryngoscope, 133:506-511, 2023.

Frequent Recurrence of Sinonasal Inverted Papilloma With Carcinoma In Situ in a Multifocal Attachment Pattern: A Case Report and Review of the Literature.

Sinonasal inverted papilloma (SIP) is a benign tumor originating from the nasal cavity and paranasal sinuses. Sinonasal inverted papilloma is characterized by local infiltration, high recurrence, and malignant transformation, and its associated dysplasia ranges from mild, moderate, severe, carcinoma in situ (CIS) to invasive squamous cell carcinoma. Sinonasal inverted papilloma with carcinoma in situ (IPwCIS) is the highest degree of dysplasia, which is a stage of malignant transformation of IP. Surgical excision and proper adjuvant therapy can help reduce recurrence rates and suppress further deterioration. In this study, we present a patient with IPwCIS who developed 3 recurrences with a multifocal attachment pattern in less than 18 months. We report the clinical manifestations, development, and treatment process in detail. We also performed a literature review to analyze the characteristics of the disease. Despite comprehensive treatment methods, tumor recurrence and further deterioration of IPwCIS persist.

Clinicopathological predictors of repeated recurrence in sinonasal inverted papilloma.

PURPOSE: To evaluate association between clinical and pathological findings and repeated recurrence in sinonasal inverted papilloma. METHODS: Retrospective cohort study conducted at a tertiary care teaching hospital included all patients operated for inverted papilloma from January 2010 to December 2019. Patients were categorized as primary and recurrent cases. Based on disease status at follow-up, they were subcategorized into 'primary with no recurrence' (PnR), 'primary with recurrence' (PwR), 'recurrent with no further recurrence' (RnR), and 'recurrent with further recurrence' (RwR) groups. Data including demography, clinical, endoscopic and pathological findings were collected and analyzed. RESULTS: Increased incidence of pale appearance of lesion in RnR group (p = 0.017), polypoidal appearance in primary group (p = 0.002) and fibrous appearance in the recurrent group (p = 0.002) were statistically significant. Predominant epithelium was combined respiratory and squamous epithelium in primary and recurrent groups and also in RnR group (p = 0.019), while it was squamous (p = 0.024) in RwR group. Epithelial hyperplasia was more common in primary and RnR groups. Oncocytic change, cystic dilatation, microabscess and squamous metaplasia were seen more in recurrent and RnR groups. Cytoplasmic glycogenation was more in recurrent and RwR groups. Stroma was predominantly edematous in all the groups. CONCLUSIONS: Patients with recurrence are younger and present earlier than those with primary disease. Fleshy appearance and pink/red colour of tumour, lining epithelium being squamous and cytoplasmic glycogenation could be considered as features predicting recurrence. Negative predictors of recurrence of IP include pale appearance of tumour, combined respiratory and squamous epithelium lining and squamous metaplasia.