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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

[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.

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.

Prognostic significance of p16, VEGF, and p53 expression patterns, Krouse stage, and smoking status in sinonasal inverted papillomas

AIM

The aim of our study is to analyze the staining models for VEGF, p16, and p53, as well as to understand the biology of inverted papilloma caused by smoking.

MATERIALS AND METHODS

Thirty-one cases, diagnosed with sinonasal inverted papilloma between 2015 and 2019, were included. Demographic data such as age and gender, admission symptoms of the patients, and anatomical location, stage, surgical technique, and recurrence information were obtained from clinical follow-up files. Immunohistochemical staining for p16, VEGF, and p53 were performed on patient materials.

RESULTS

In our study, the female to male ratio was 9.33 with an average age of 53.137 ± 13.96 years. Of the patients, 17 were nonsmokers and 14 were smokers. No significant relationship was found between smoking status and relapse and dysplasia. In contrast, a significant relationship between the Krouse stage and dysplasia (P = 0.005) was observed. A similar significant relationship was observed between p16 immunohistochemical expression and dysplasia (P = 0.030). On the other hand, VEGF and p53 immunohistochemical expressions were not significantly related with dysplasia and recurrence.

CONCLUSIONS

Inverted papillomas are benign tumors that clinically give symptoms similar to nasal polyps. However, recurrence and malignant transformation potential exist and the factors causing this risk are not clearly identified. In our study, no malignant transformation was observed in patients who were admitted to our hospital.

Long-term changes in serum squamous cell carcinoma antigen levels after surgery in patients with sinonasal inverted papilloma

OBJECTIVES

This study aimed to examine whether serum SCCA levels can be used as clinical markers for monitoring recurrence of sinonasal inverted papilloma (IP) during the follow-up period after surgery. We measured long-term changes in serum levels of SCCA after surgery in patients with IP and examined whether postoperative SCCA levels were associated with IP recurrence.

METHODS

Twenty-five consecutive patients (13 with primary IPs and 12 with recurrent IPs after their previous surgery) were included in this study. All patients underwent endoscopic or external surgery. Postoperative serum SCCA levels were measured 3 months after surgery and every 3 - 12months during the follow-up. The optimal cut-off values of postoperative SCCA levels to predict subsequent recurrence of IP were evaluated using ROC analysis.

RESULTS

Preoperative serum levels of SCCA were higher than the upper limit of normal range in most patients with both primary and recurrent IP, and significantly decreased after surgery. Thus, the presence of IP was closely associated with elevated serum SCCA levels. Moreover, postoperative elevation of SCCA levels was closely associated with subsequent recurrence of IP. Postoperative SCCA levels in 5 patients with recurrence were significantly higher than those in 20 patients without recurrence. The optimum cut-off value of SCCA levels to predict subsequent recurrence of IP 3 months after surgery was 1.85 ng/ml, with a sensitivity of 100.0 % and a specificity of 90.0 %.

CONCLUSIONS

These findings suggest that SCCA can be a tumor marker of IP. It is also suggested that postoperative elevation of SCCA levels is a clinical marker for monitoring the recurrence of IP during the follow-up period. A SCCA cut-off value of 1.85 ng/ml postoperatively may predict the subsequent recurrence of IP with high sensitivity and specificity.

Modified Endoscopic Denker's Approach for Management of Anterior Maxillary Sinus Tumors: Multicenter Series of 58 Cases

OBJECTIVES

Tumors involving the anterior portion of the maxillary sinus remain technically challenging to access via an endoscopic approach. The modified endoscopic Denker's (MED) procedure was recently introduced to address such lesions. We present a multicenter series of 58 patients with tumors involving the anterior maxillary sinus successfully resected using a MED procedure and present the clinical outcomes and complications.

METHODS

A multi-institution retrospective chart review was performed on patients who underwent the MED approach for the management of tumors involving the anterior maxillary sinus from 2009 to 2020. Demographic data, pathology, surgical outcomes, and complications were reviewed.

RESULTS

Fifty-eight patients were identified, including 34 (58.6%) male and 24 (41.4%) female patients. The most common pathologies included: inverted papilloma (n = 27; 46.6%), adenoid cystic carcinoma (n = 9; 15.5%), and squamous cell carcinoma (n = 8; 13.8%). Thirty-eight patients (65.5%) underwent MED alone, while 20 (34.5%) had combined expanded endonasal approaches for lesions extending beyond the maxillary sinus. All maxillary sinus lesions were successfully accessed with the MED procedure without the need for an additional approach. After a mean follow-up of 30 months (range, 1-127), 8 of 58 (13.8%) patients developed complications related to the MED, including epiphora requiring an additional procedure (n = 4; 6.9%), prolonged facial/palatal numbness (n = 3; 5.2%), severe epistaxis (n = 1; 1.7%), and vestibular stenosis (n = 1; 1.7%), the latter of which occurred following postoperative radiation.

CONCLUSION

The MED procedure is a safe and highly effective approach for benign and malignant tumors involving the anterior maxillary sinus. However, patients should be counseled preoperatively on potential complications including the risk of facial numbness and epiphora.

High CT values relative to the brainstem differentiate inverted papillomas from nasal polyps

OBJECTIVES

A diagnostic indicator for the differentiation of inverted papillomas (IPs) from inflammatory nasal polyps (NPs) has not been established. This study aimed to evaluate whether CT attenuation values relative to those of the brainstem (relative CT number) could be useful for differentiating IPs from NPs.

MATERIAL AND METHODS

Consecutive patients who were pathologically diagnosed with IP or NP between 2005 and 2019 were retrospectively identified. Relative CT numbers were compared between the two patient groups. The factors with predictive power for differentiating IPs from NPs were identified by univariate and multivariate logistic regression analyses.

RESULTS

One hundred and twenty-two sinonasal masses were finally analysed (IP, 51 cases; NP, 71 cases). Relative CT numbers were significantly higher in IP than in NP (P < 0.001). Univariate logistic regression analysis showed relative CT number, bone erosion and bone thickening to have predictive value for differentiating IPs from NPs (relative CT number, P < 0.001; bone erosion, p = 0.04; bone thickening, P < 0.001). In the multivariate logistic regression analysis, relative CT number and bone thickening had predictive value for distinguishing IP from NP (relative CT number, p < 0.001; bone thickening, p = 0.02). The optimum cut off value calculation from the area under the receiver operating characteristics curve indicated that a relative CT number >1.3 was significantly associated with IP (sensitivity, 72.6%; specificity, 87.3%). Within cases not showing bone thickening, only the relative CT number was a predictive factor for differentiating IPs from NPs in the univariate analysis.

CONCLUSIONS

High relative CT numbers could potentially indicate IP, and their measurement could provide a basis for differentiating IPs from NPs.

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

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

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.

Squamous Cell Carcinoma Arising from Sinonasal Inverted Papilloma

Sinonasal inverted papillomas occasionally undergo malignant transformation into squamous cell carcinoma, which can be associated with EGFR mutations. Since biopsy can potentially under-sample the tumor, CT and MRI can provide clues as to the presence of malignant transformation. In particular, this entity tends to appear different from benign inverted papilloma on imaging, including prominent bone erosions, necrosis, low diffusivity in the solid tumor components, and absence of the cerebriform pattern on MRI. The radiology findings, pathology features, and management of squamous cell carcinoma arising from inverted papilloma are described.

A rare case of nasal Schneiderian (inverted) papilloma associated with basaloid squamous cell carcinoma

Sinonasal inverted papilloma (IP) is a benign, locally aggressive epithelial neoplasm. In less than 9% of cases it is associated with malignancies, typically conventional squamous cell carcinomas (SCC), while other histological variants have been less frequently reported. We describe the third case of basaloid squamous cell carcinoma (BSCC) arising in nasal IP. An 81-year-old female patient presented with a pinkish irregular lesion on the nasal septum. Biopsy was consistent with IP and carcinoma in situ. Two surgical procedures were needed to obtain radical excision. Histology on the surgical specimen revealed BSCC. Seven months after surgery, there was no evidence of disease recurrence. Although IP is more frequently associated with conventional SCC, other malignancies should be considered. The histological differential diagnosis should be supported by immunohistochemistry. The generally-recommended treatment for sinonasal BSCC is complete surgical resection, although this may be a problem in multifocal distributions, as in the present case.

Cervical nodal metastasis after malignant conversion of sinonasal inverted papilloma: Report of a rare case and literature review

Malignant conversion of sinonasal inverted papilloma (SNIP) occurs in approximately ten percent of cases. These tumors are classically described as locally destructive, but without metastatic potential. Only four cases of malignant conversion with cervical nodal metastases have been described in the English literature. We present the rare case of a 61-year-old Caucasian male with a nasopharyngeal recurrence of malignant SNIP with cervical and retropharyngeal nodal metastases. The patient underwent endoscopic transpterygoid with nasoseptal flap reconstruction, followed by staged bilateral and retropharyngeal node dissection. Histopathology of the specimens demonstrated poorly differentiated invasive nonkeratinizing squamous cell carcinoma with inverted-type features. Three months after surgery, the patient suffered from C1-C2 fractures consistent with osteoradionecrosis and expired. Although the rate of malignant conversion of SNIP is low, this case highlights the need for aggressive, definitive treatment and surveillance.

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

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

Genetic mutation analysis of the malignant transformation of sinonasal inverted papilloma by targeted amplicon sequencing

BACKGROUND

The mechanism underlying the malignant transformation of inverted papilloma (IP) has not yet been elucidated.

METHODS

To clarify the genes responsible for the malignant transformation, we analyzed 10 cases of IP, 8 of IP with dysplasia, and 11 of squamous cell carcinoma (SCC) by targeted amplicon sequencing.

RESULTS

The number of mutant genes increased in the order of IP < dysplasia < SCC. Significant differences were observed in the mutation rates of three genes (KRAS, APC and STK11) in particular. TP53 was altered frequently in each group and might be involved in malignant transformation based on to the site of the mutation. A comparison of the genetic variants by region of IP tissue among patients with IP alone, and those with dysplasia or SCC revealed significant differences in the mutation rate of the KRAS gene.

CONCLUSION

Identification of genetic mutations in KRAS is effective for predicting the malignant transformation of IP.

Comparison of Open versus Endoscopic Resection of Inverted Papilloma

Background

Lateral rhinotomy with medial maxillectomy has served as the standard for surgical management of inverted papilloma (IP) in the pre–endoscopic era; since the late 1980s, endoscopic techniques have emerged as the minimally invasive alternative. The objective of this study was twofold: (1) to compare operative parameters, complications, and recurrence rates and (2) predictive factors for recurrence for open versus endoscopic cases of IP resection.

Methods

Retrospective data analysis was performed on 68 patients with histopathologically confirmed IP treated at a tertiary care medical center from January 1983 to May 2005. Parameters for comparison included operative time (OT), estimated blood loss (EBL), length of hospital stay (HS), complications, and recurrence rate. Predictive factors for recurrence including open versus endoscopic cases, primary versus secondary IP, and tumor by Krouse stage were analyzed.

Results

The average age at time of presentation was 57.4 years with a male/female ratio of 2.2:1. Forty-nine patients underwent endoscopic resection, 13 patients underwent open resection, and 6 patients underwent limited open resection. Average OT and EBL were statistically similar for the three groups, whereas the average HS was statistically shorter (p = 0.002) for the endoscopic group. Biopsy-proven recurrence was noted in 11 (22%) endoscopic cases, 5 (39%) open cases, and 3 (50%) limited open cases. After reresection, all patients were free of disease. Mean follow-up was 16 months, 56 months, and 69 months for the endoscopic, open, and limited open groups, respectively. Analysis of predictive factors indicated that the surgical approach and primary versus secondary IP, regardless of approach, did not statistically impact recurrence rate. Chi-square analysis illustrated that patients with advanced-stage IP had a higher risk of recurrence (p = 0.002), regardless of surgical technique.

Conclusion

In this series, endoscopic resection of IP was associated with shorter HS and equivalent EBL and OT compared with the open groups. The overall recurrence rate was lower in the endoscopic group with acceptable morbidity compared with the open and limited open groups. Thus, the endoscopic approach may serve as a superior alternative to the open approaches for successful extirpation of IP.

Endoscopic management of maxillary sinus inverted papilloma attachment sites to minimize disease recurrence

BACKGROUND

Inverted papillomas (IPs) are benign neoplasms, most commonly arising from the mucosal lining of the maxillary sinus. IPs can have single or multifocal sites of attachment. Although pedicle location is an important factor to consider in surgical planning, it is less clear whether the location or number of IP attachment sites hold any prognostic value. Herein, we aimed to determine the prognostic significance of the number and location of attachment sites of IPs originating from the maxillary sinus when managed by a pure endoscopic approach.

METHODS

This was a single-center, single-surgeon retrospective chart review. Patients with maxillary sinus IPs who were managed by endoscopic approaches only, from January 1, 2010 to June 30, 2016, were identified. Demographic data, operative technique, number and location of IP attachment sites, follow-up duration, recurrence, and presence of malignant transformation were captured.

RESULTS

Twenty-eight maxillary IP patients (61% males) were included, with a mean age of 54.9 (standard deviation (SD): 16.5) years. Approximately 36% of patients were referred from other institutions for management of recurrent IPs after failing previous surgical treatment. All patients were managed with an endoscopic approach, and all required an endoscopic medial maxillectomy to facilitate access to the maxillary sinus. At a mean follow-up of 31.1 (SD: 22.6) months, there were no recurrences identified. IPs with single (46%) and multifocal (54%) attachments were predominately to the medial and lateral walls. Maxillary IPs with multifocal attachments most frequently involved 2-3 walls of the sinus. Osteitis (36%) was commonly seen.

CONCLUSION

IPs originating from the maxillary sinus frequently had multifocal attachments, but this did not impact disease recurrence. Despite the surgical challenges of accessing all of the maxillary sinus walls, IPs originating from the maxillary sinus can be effectively managed via a pure endoscopic approach.

An Interesting Case of Oral Inverted Ductal Papilloma

Ductal papillomas are rare benign papillary tumours of the minor salivary glands. Previously they have been classified into three subtypes: inverted ductal papilloma (IDP), sialadenoma papilliferum and intraductal papilloma. The oral inverted ductal papilloma is the least common of these lesions, with 48 cases reported to date in a search of the English-language literature. We describe an interesting case of oral IDP and highlight the pertinent clinical and histopathological features. Importantly, unlike the histologically similar inverted papilloma (IP) of the nose and paranasal sinuses, oral IDP is a completely benign lesion and is not associated with malignant change. Clinical relevance: This case report aims to raise awareness of the lesion, oral inverted ductal papilloma (IDP). We outline the clinical features and unique histopathology of oral IDP so that clinicians may correctly diagnose such a lesion and implement appropriate treatment.

Exophytic sinonasal papillomas and nasal florid papillomatosis: A retrospective study

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Inverted schneiderian papilloma of the supraglottis: Case report

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

Different characteristics of a single sinonasal inverted papilloma from sequential PET-CT: A case report

RATIONALE

Inverted papilloma (IP) is a benign tumor that should be monitored carefully because it frequently recurs and has the potential to become malignant.

PATIENT CONCERNS

We report a case of a 59-year-old woman who presented with a mass which had been found incidentally on positron emission tomography computed tomography (PET CT).

DIAGNOSES

Using endoscopy and CT, the preoperative diagnosis was inverted papilloma. PET CT showed a mass with hot uptake in the left ethmoid and frontal sinus (maximum standardized uptake value (SUVmax) = 7.80).

INTERVENTIONS

We performed endoscopic sinus surgery (ESS) using 4 mm 0° and 70° endoscopes under general anesthesia. After 15 months of follow-up, remnant masses existed in the left frontal and supraorbital ethmoid cells. In the second PET CT taken at this time, a mass with lower SUV compared to the preoperative PET was observed in the lateral side of the left frontal sinus (SUVmax= 1.71). Revision ESS was performed using the "above and below" technique.

OUTCOMES

Two years after initial surgery, follow-up CT showed there was no tumor recurrence in the frontal sinus or supraorbital ethmoid cell. There were no complications such as numbness in the forehead area after the operations.

CONCLUSION

If the tumor is located at a site that is difficult to reach with an endoscope alone, it is faster and less painful to choose a more convenient approach for the patientand it can avoid unnecessary cost burden. It should also be noted that the SUV of PET is not a tool to distinguish IP from other inflammatory polyps or cancer.

Sinonasal undifferentiated carcinoma originating from inverted papilloma: A case report

RATIONALE

Sinonasal inverted papilloma (IP) is a locally aggressive tumor found in the schneiderian membrane, lining the nasal cavity and paranasal sinuses.

PATIENT CONCERNS

We report a case of a 63-year-old woman with undifferentiated carcinoma (UC) arising in an IP in the left maxillary sinus.

DIAGNOSES

The preoperative diagnosis was IP of the maxillary sinus.

INTERVENTIONS

We performed endoscopic medial maxillectomy to remove the remnant mass in the left maxillary sinus.

OUTCOMES

Histological examination of the specimen revealed typical area of IP and sinonasal UC.

LESSONS

Clinicians should consider sinonasal UC in the differential diagnosis of malignancy arising in the sinonasal IP.

Association of Krouse Classification for Sinonasal Inverted Papilloma With Recurrence: A Systematic Review and Meta-analysis

Importance

The risk factors for the recurrence of sinonasal inverted papilloma are still unclear.

Objective

To investigate the potential association between the Krouse classification and the recurrence rates of sinonasal inverted papilloma.

Data Sources

The EMBASE and MEDLINE databases were searched for the period January 1, 1964, through September 30, 2016, using the following search strategy: (paranasal sinuses [Medical Subject Headings (MeSH) terms] OR sinonasal [all fields]) AND (inverted papilloma [MeSH terms] OR (inverted [all fields] AND papilloma [all fields]).

Study Selection

The inclusion criteria were (1) studies including sinonasal inverted papilloma only and no other forms of papillomas, such as oncocytic papilloma; (2) minimum follow-up of 1 year after the surgery; and (3) clear report of cases (recurrence) and controls according to the Krouse classification system or deducible from the full-text article. Literature search was performed by 2 reviewers. Of the 625 articles retrieved in the literature, 97 full-text articles were reviewed. Observational cohort studies or randomized controlled trials were included, and the following variables were extracted from full-text articles: authors of the study, publication year, follow-up data, and number of cases (recurrence) and controls (no recurrence) in each of the 4 stages of the Krouse classification system.

Data Extraction and Synthesis

The Meta-analysis of Observational Studies in Epidemiology (MOOSE) guidelines were followed. Odds ratios (ORs) and 95% CIs were estimated, and data of included studies were pooled using a random-effects model.

Main Outcomes and Measures

The main outcome was recurrence after surgical removal of sinonasal inverted papilloma according to each stage of the Krouse classification system.

Results

Thirteen studies comprising 1787 patients were analyzed. A significant increased risk of recurrence (51%) was highlighted for Krouse stage T3 disease when compared with stage T2 (pooled OR, 1.51; 95% CI, 1.09-2.09). No significant difference in risk of recurrence was found between Krouse stages T1 and T2 disease (pooled OR, 1.14; 95% CI, 0.63-2.04) or between stages T3 and T4 (pooled OR, 1.27; 95% CI, 0.72-2.26).

Conclusions and Relevance

Inverted papillomas classified as stage T3 according to the Krouse classification system presented a 51% higher likelihood of recurrence. Head and neck surgeons must be aware of this higher likelihood of recurrence when planning and performing surgery for sinonasal inverted papilloma.

Transnasal endoscopic medial maxillectomy in recurrent maxillary sinus inverted papilloma

BACKGROUND

Maxillary sinus inverted papilloma entails medial maxillectomy and is associated with high incidence of recurrence.

OBJECTIVE

To study the impact of prior surgery on recurrence rate after transnasal endoscopic medial maxillectomy.

METHODOLOGY

Eighteen patients with primary and 33 with recurrent maxillary sinus inverted papilloma underwent transnasal endoscopic medial maxillectomy. Caldwell-Luc operation was the primary surgery in 12 patients, transnasal endoscopic resection in 20, and midfacial degloving technique in one. The follow-up period ranged between 2 to 19.5 years with an average of 8.8 years.

RESULTS

Recurrence was detected in 8/51 maxillary sinus inverted papilloma patients (15.7 %), 1/18 of primary cases (5.5 %), 7/33 of recurrent cases (21.2 %); 3/20 of the transnasal endoscopic resection group (15%) and 4/12 of the Caldwell-Luc group (33.3%). Redo transnasal endoscopic medial maxillectomy was followed by a single recurrence in the Caldwell-Luc group (25%), and no recurrence in the other groups.

CONCLUSION

Recurrence is more common in recurrent maxillary sinus inverted papilloma than primary lesions. Recurrent maxillary sinus inverted papilloma after Caldwell-Luc operation has higher incidence of recurrence than after transnasal endoscopic resection.

Malignant transformation of nasal inverted papilloma into sarcomatoid carcinoma

A 57 year-old, male presented with a chronic unilateral nasal obstruction and epistaxis. Intranasal endoscopy showed multiple polypoid lesions. The computed tomography exam revealed a heterogeneous mass that occupied the right nasal cavity with osteolysis of the middle and lower cone causing fluid retention of the right maxillary sinus. He underwent resection of these lesions. Pathological examination revealed malignant transformation of nasal inverted papilloma into sarcomatoid carcinoma. This case report highlights the importance of considering malignant transformation in the differential diagnosis of polypoid lesions.

Endoscopic surgery of a sinonasal inverted papilloma: Surgical strategy, follow-up, and recurrence rate

BACKGROUND

Sinonasal inverted papilloma (SNIP) is noted for its high rate of recurrence and malignant transformation. Although many clinical studies have demonstrated the effectiveness of the endoscopic approach for SNIP, the surgical strategy has been the subject of much debate.

OBJECTIVE

To evaluate the effectiveness of the endoscopic endonasal approach in SNIP.

METHODS

A systematic review of patients with a diagnosis of SNIP and who had surgery at our institution from June 2005 to March 2013 was performed. All the patients who had postoperative follow-up for >2 years were enrolled. Each case was categorized into one of four stages as reported by Krouse. Demographic and tumor date, operative approach, complications, and recurrence rates were collected.

RESULTS

A total of 125 patients were included in this study. There were 17 patients in stage 1, 40 in stage 2, 57 in stage 3, and 11 in stage 4. The overall recurrence rate was 8.0%. There was no significant difference in recurrence among the stages (all p > 0.05). Recurrence after endoscopic endonasal approach (8.4%) and a combined endoscopic and open exposure procedure (5.6%) were not significantly different (p > 0.05). The recurrence rate was significantly (p < 0.05) higher in patients with revision (15.6%) than in patients in the primary cases (3.8%). A common site of tumor origin was recorded to be from the maxillary sinus (40.2%). Twenty percent of recurrences were observed up to 5 years after surgery.

CONCLUSION

Endoscopic surgery may be preferred for treating SNIP. The elevated recurrence rate after revision emphasized the significance of the first surgery. We encourage a follow-up period of at least 5 years.

[Inverted papilloma of the bladder: a rare benign tumor: a case report]

Le papillome inversé de la vessie est une tumeur urothéliale rare et bénigne, qui apparaît généralement à l’âge adulte avec une nette prédominance masculine. L’hématurie macroscopique est le symptôme révélateur le plus fréquent, les signes radiologiques et cystoscopiques ne sont pas toujours spécifiques. Son diagnostic de certitude repose sur l’examen anatomopathologique. Le traitement est basé sur la résection endoscopique avec coagulation du lit tumoral. Une surveillance au long cours est nécessaire en raison de son association relativement fréquente avec le carcinome urothélial.

Inverted papilloma of the bladder is a rare and benign urothelial tumor, which usually affects adult patients with a clear male predominance. Macroscopic haematuria is the most frequent revealing symptom. Radiologic and cystoscopic signs are not always specific. Definitive diagnosis is based on anatomo-pathological examination. Treatment is based on endoscopic resection with coagulation of the tumor bed. Long term monitoring is necessary due to its common association with urothelial carcinoma.

Oral inverted ductal papilloma: not related to HPV

Oral inverted ductal papilloma (OIDP) is a rare, nonrecurrent,benign lesion of salivary glands. The etiologyis still poorly understood; the correlation with humanpapilloma virus (HPV) is controversial. Herein wepresent a 74-year-old man with a tumor in lower lip.Incisional biopsy was performed and the histologicaldiagnosis was OIDP. Inno-LiPA assay, based onpolymerase chain reaction and in situ hybridizationwas used to assess for HPV with no detection of viralDNA. Surgical excision was performed without anyrecurrences after two years of follow-up.

Inverted Papilloma of the Bladder Coexisting with Urothelial Carcinoma. A Case Report

BACKGROUND

Inverted papilloma (IP) is an unusual benign neoplasm, most commonly found in the bladder. Cases of malignant transformation have been reported in the past, although most of them are now considered to be urothelial carcinomas with an inverted growth pattern.

CASE

A 54-year-old man was diagnosed with urothelial carcinoma in situ (UCIS), high-grade papillary urothelial carcinoma (HGPUC), and IP by transurethral resection specimen of the bladder. The urothelial carcinoma cells were seen colonizing the inverted papilloma.

CONCLUSION

The coexistence of IP with UCIS and HGPUC is rare. Immunohistochemistry helps distinguish between IP and UC in difficult cases such as this one. A brief review of other reported cases of inverted papilloma coexisting with urothelial carcinoma in the English literature over the past 25 years is presented.

Rate of recurrence and malignant transformation in 88 cases with inverted papilloma between 1998-2008

Conclusions The recurrence rate of IP in the current study is comparable to international and national studies. When the primary tumour was located in the frontal or the sphenoid sinus, the tumour seemed more likely to recur. Some recurrences were more than 2 years after primary surgery, suggesting continued need for long-term follow-up. The rate of malignant transformation in inverted papilloma cases has not changed in Denmark. Objectives Inverted papillomas are benign tumours located in the nasal cavity and paranasal sinuses. They are known for their tendency to recur after surgery and show invasive growth, causing bone remodulation and the association with malignant transformation. The introduction of endoscopic sinus surgery and computer aided sinus surgery over the last decades has made this tumour more approachable with less cosmetic and functional damage. The objective of this study is to establish whether the recurrence rate and the rate of malignant transformation of IP have changed with the application of these new techniques. Method A retrospective study between 1998-2008 including 88 cases with inverted papilloma. Results In total, 25.3% had recurrence. Combined surgical approach with endoscope/open approach had the lowest rate of recurrence. A malignant transformation in the postoperative histological examination was found in 8.9%.

Clinical and histological aspects of malignant inverted sinonasal papilloma. Two case reports

The inverted sino-nasal papilloma is a benign epithelial lesion, ranging from 1% to 5% of the tumors that reside in this area. It is characterized by a tendency towards local bone destruction, recurrence and malignant transformation. This is a presentation of two cases diagnosed and surgically treated for malignant inverted papiloma, which started in the epithelium of the maxillary sinuses. The cases had in common the late presentation of the patient to the surgeon, thus the local destruction was significant with extension towards the eye socket and the base of the skull. The treatment of choice was the surgical resection of the maxillary bone with a prosthetic reconstruction of the defect followed by radiotherapy. After a careful analysis of the two cases, a series of statements regarding the diagnosis and treatment of this rare pathology were recommended.

Surgical Outcomes of Sinonasal Inverted Papillomas in Songklanagarind Hospital

OBJECTIVE

To evaluate the surgical outcomes and recurrence rate of inverted papillomas (IPs).

MATERIAL AND METHOD

The medical records of patients diagnosed as IPs at Songklanagarind Hospital between January 2004 and December 2012 were retrospectively reviewed. Demographic data, clinical presentation, type of surgical approach, complications, and recurrence status were collected.

RESULTS

From 64 patients, 75% were male. The average age was 55 years. IPs were classified in Krouse's classification system as followed: stage I = 6.3%, stage II = 21.9%, stage III = 70.3%, and stage IV = 1.5%. The surgical approaches were divided into endoscopic endonasal approach (EEA) 60.9%, EEA combined with external approach 35.9%, and external approach 3.2%. Complications such as synechea and maxillary sinus ostium stenosis occurred in 29.7% of patients. Thirty-seven point five percent had disease recurrence after surgery, most commonly at the frontal sinus 82.4%, and sphenoid sinus 60%.

CONCLUSION

EEA is an effective treatment for IPs, especially in Krouse's classification stage I, II. The external approach combined with E A could be useful when the tumor extends to the anterolateral wall of the maxillary sinus. Finally, the surgeon must pay particular attention to the frontal and sphenoid sinus because of the high local recurrence rate.

[Analysis on the prognosis of malignant transformation of sinonasal inverted papilloma]

OBJECTIVE

To summarize the clinical characteristics and treatments of patients with malignant transformation of sinonasal inverted papilloma (SNIP), and to explore the factors influencing the prognosis of malignant SNIP.

METHOD

To retrospectively analyze the clinical data of 35 patients with malignant SNIP. The prognosis affected by age, gender, pathogenetic locations, pathology, clinical stages and treatments were analysed using Kaplan Meier, Log rank and Cox method.

RESULT

In our research, 5 years survival rate was 68.6% in malignant SNIP. There were 3 factors effecting the 5 years survival rate of malignant SNIP: clinical staging, histopathological features and treatments while gender, age, disease location, and percentage of the malignant cell in the entire tumor tissue had no effect on overall survival rate. Clinical staging and treatment were the independent factors that influenced the prognosis of malignant SNIP (P value was 0.019 and 0.006).

CONCLUSION

Risk factors that independently influence the survival of patients with malignant SNIP were the clinical staging and treatment. The degree of histo pathological features can be the secondary indicator to judge the prognosis of malignant SNIP. Endoscopic surgery or comprehensive therapy performed on patients properly is therapeutically effective.

[Inverted papiloma and its rare forms]

Authors address the issue of a frequent benign tumour of the nasal cavity and paranasal sinuses -  inverted papilloma. They analyse the available diagnostic methods and treatment options. On the background of selected case reports of a rare malignant transformation they emphasize the need for longterm dispensarization as a part of management plan for patients with this oncological disease.

Multifocal inverted papillomas in the head and neck

Inverted papilloma is a rare benign neoplasm that usually originates in the lateral nasal wall. It can be a locally aggressive lesion and invade nearby structures. While primarily a nasal neoplasm, cases of an inverted papilloma involving the temporal bone, pharynx, nasopharynx, and lacrimal sac have been reported. We describe the case of a 67-year-old man with a history of nasal inverted papilloma who presented with a recurrent nasal mass and a large mass on the left side of his upper neck. The patient's history included inverted papillomas in multiple locations: the temporal bone, the sinonasal tract, and the nasopharynx. The new neck mass raised a concern for malignant degeneration and metastasis, but pathology demonstrated that it was a benign inverted papilloma. No clear etiology for the new neck lesion was evident except for an origin in salivary gland tissue. However, there was no physical connection between the neck mass and the submandibular gland identifiable on pathologic evaluation. This case illustrates the need for an aggressive primary resection to minimize local recurrence, as well as adequate surveillance to address recurrences early. Given the potential for multicentricity, patients with a typical sinonasal inverted papilloma should undergo a complete head and neck examination as part of their follow-up.