Squamous cell carcinoma arising in inverted papilloma

The Role of Positron Emission Tomography for the Management of Sinonasal Malignancies: A Systematic Review

BACKGROUND

Positron emission tomography (PET) scan is a valuable imaging modality widely used in the management of cancers. Its usage is well defined for most head and neck malignancies. However, there is a lack of consensus regarding the utility of PET scan for sinonasal malignancies. This is highlighted by the latest international consensus statement on endoscopic skull base surgery.

OBJECTIVE

This systematic review aims to clarify the role of PET scan in the management of sinonasal malignancies.

METHODS

We conducted a comprehensive literature search using PubMed, MEDLINE, EMBASE, Web of Science, CINAHL, and Cochrane databases for research studies of interest. The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) updated statement was used to guide the review.

RESULTS

In total, 1807 articles were assessed for eligibility. Thirty-nine original papers, published between 2004 and 2021, met inclusion criteria. Seven articles focused on the role of PET scan for inverted papilloma, 23 for sinonasal carcinoma, 4 for melanoma, and 3 for lymphoma, and finally, 3 articles focused on the use of specific PET scan tracers for sinonasal malignancies. Qualitative summaries for each potential role of PET scans were provided. In general, included studies were retrospective in nature with low level of evidence.

CONCLUSIONS

In general, and across all types of sinonasal malignancies, PET scan yielded positive results regarding detection and initial staging. It was also considered as the modality of choice for detection of distant metastases, except in the case of sinonasal lymphoma. PET scan's main limit resides in its inability to detect lesions in or close to the metabolic activity of the brain.

Prognostic factors and outcomes in minimal access resections of skull base and sinonasal epithelial malignancy

BACKGROUND

Sinonasal epithelial malignancies are uncommon tumours but represent a challenge to treatment given their close proximity to the orbit, brain and cranial nerves. Traditional external surgical approaches have potential for significant functional and cosmetic morbidity. An endoscopic approach provides the surgeon with good access for tumour removal and enables surveillance postoperatively. This study aimed to assess outcomes of an endoscopic approach to sinonasal epithelial malignancy and evaluate factors that may influence its utility.

METHODS

A case series was performed involving consecutive patients treated with endoscopic or endoscopic-assisted surgery for epithelial sinonasal malignancy. Stratification included TNM staging, histopathology, surgical approach, margin status, perineural involvement and adjuvant or neoadjuvant therapy. At follow-up, complications, local control, nodal status and evidence of distant metastases were recorded. Statistical analyses to identify risk factors for developing recurrence and survival differences were performed.

RESULTS

Thirty-five patients were assessed in this study (59.2 ± 11.4 years, 42.9% female). T stage at presentation was T1 in 11.4%, T2 in 17.1%, T3 in 22.9% and T4 in 48.6%. The 3 and 5 year disease specific survival were 91.3% (SE 5) and 71.1% (SE 10). The only factors to influence survival outcomes were perineural invasion of tumour and positive margins at the time of initial surgery. Large tumours did not limit the utility of an endoscopic approach.

CONCLUSION

Endoscopic approach is a safe and oncologically equitable treatment approach to external approaches in the management of epithelial sinonasal malignancy. As with external approaches, perineural invasion of malignance is a poor prognostic factor.

Human Papillomavirus-Related Carcinomas of the Sinonasal Tract

Purpose of review

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

Recent findings

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

Summary

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

Sinonasal Inverted Papilloma and Squamous Cell Carcinoma: Contemporary Management and Patient Outcomes

Simple Summary

Inverted papillomas are benign sinonasal tumors that can recur or become cancerous. The mainstay of treatment is surgical resection. We summarize the biology of inverted papillomas and review surgical outcomes in an effort to define the current treatment strategy.

Abstract

Inverted papillomas (IP) are the most common sinonasal tumor with a tendency for recurrence, potential attachment to the orbit and skull base, and risk of malignant degeneration into squamous cell carcinoma (SCC). While the overall rate of recurrence has decreased with the widespread adoption of high-definition endoscopic optics and advanced surgical tools, there remain challenges in managing tumors that are multiply recurrent or involve vital neurovascular structures. Here, we review the state-of-the-art diagnostic tools for IP and IP-degenerated SCC, contemporary surgical management, and propose a surveillance protocol.

Preoperative Prediction of Malignant Transformation of Sinonasal Inverted Papilloma Using MR Radiomics

Purpose

Accurate preoperative prediction of the malignant transformation of sinonasal inverted papilloma (IP) is essential for guiding biopsy, planning appropriate surgery and prognosis of patients. We aimed to investigate the value of MRI-based radiomics in discriminating IP from IP-transformed squamous cell carcinomas (IP-SCC).

Methods

A total of 236 patients with IP-SCC (n=92) or IP (n=144) were enrolled and divided into a training cohort and a testing cohort. Preoperative MR images including T1-weighted, T2-weighted, and contrast enhanced T1-weighted images were collected. Radiomic features were extracted from MR images and key features were merged into a radiomic model. A morphological features model was developed based on MR morphological features assessed by radiologists. A combined model combining radiomic features and morphological features was generated using multivariable logistic regression. For comparison, two head and neck radiologists were independently invited to distinguish IP-SCC from IP. The area under the receiver operating characteristics curve (AUC) was used to assess the performance of all models.

Results

A total of 3948 radiomic features were extracted from three MR sequences. After feature selection, we saved 15 key features for modeling. The AUC, sensitivity, specificity, and accuracy on the testing cohort of the combined model based on radiomic and morphological features were respectively 0.962, 0.828, 0.94, and 0.899. The diagnostic ability of the combined model outperformed the morphological features model and also outperformed the two head and neck radiologists.

Conclusions

A combined model based on MR radiomic and morphological features could serve as a potential tool to accurately predict IP-SCC, which might improve patient counseling and make more precise treatment planning.

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

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

MRI of Sinonasal Malignancies

ABSTRACT

Sinonasal cavity is an important subsite in head and neck tumors. There are a myriad of malignancies that present within this area. Adequate staging for treatment planning requires multimodality evaluation. Magnetic resonance imaging (MRI) forms an important component in the evaluation of sinonasal tumors. We sought to review the most common sinonasal tumors, including sinonasal anatomy, clinical features, and common imaging features. A literature review was performed to evaluate common sinonasal tumors. Owing to the different tissue types within the sinonasal cavity, there are multiple different tumor pathologies within the sinonasal compartment. Most present in adults although some present in the young. Many of these tumor types have imaging overlaps, although some have a characteristic appearance. MRI can aid in soft tissue delineation, evaluation of multicompartmental extension, intracranial spread, and perineural spread. Sinonasal tumors are a heterogeneous group for which soft tissue delineation via MRI forms an important role in ensuring adequate treatment planning to improve outcomes, decreasing morbidity, and improve functional outcomes.

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

Importance

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

Objective

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

Data Sources

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

Study Selection

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

Data Extraction and Synthesis

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

Main Outcomes and Measures

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

Results

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

Conclusions and Relevance

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

COX-2 Overexpression in Schneiderian Papillomas

Background

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

Objective

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

Methods

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

Results

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

Conclusion

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

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Unique case of inverted papilloma of septum with nasopharyngeal carcinoma: Is it a metachronous tumour?

Inverted papilloma is a rare and benign tumour. It affects the nasal cavity and paranasal sinuses, has a high rate of recurrence and is associated with malignant transformation. Only few cases of a poorly differentiated carcinoma arising from inverted papilloma have been reported, none of which in the nasopharynx. We report a case of a 37-year-old female, who presented originally in 2012 with inverted papilloma of the nasal septum which was surgically resected. Nasopharyngeal biopsy from 2014 was reported as carcinoma in situ and treated with local endoscopic resection. Three years later she presented with a solitary lesion of the right Eustachian tube opening, confirmed as invasive poorly differentiated carcinoma. Imaging revealed T4 N2b M0 malignancy with skull base and prevertebral space invasion, likely extension into right temporal lobe and malignant adenopathy. Although rare, malignant transformation of inverted papilloma in unusual places should be considered during workup and monitoring of patients.

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

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

Squamous cell carcinoma associated with inverted papilloma: Recurrence and prognostic factors

The purpose of the present study was to review the recurrence and prognostic factors of squamous cell carcinoma (SCC) associated with inverted papilloma (IP). A retrospective chart review was conducted on 21 patients with SCC associated with IP, in the nasal cavity and paranasal sinuses, between March 2007 to March 2017. All patients underwent surgical treatment: Surgery prior to or following adjuvant therapy was performed in 17 patients (81.0%). During a mean follow-up time of 47.4 months (range, 3-123 months), 9 patients (42.9%) experienced local recurrence, and the risk factors of T4 stage and invasive orbital cavity had a significant influence on recurrence. The 1-, 3-, and 5-year overall survival rates were 90.5, 75.4 and 68.5%, and the 1-, 3-, and 5-year disease-specific survival (DSS) rates were 90.5, 80.4 and 80.4%, respectively. The prognosis of patients with stage T4 was not satisfactory compared with those with stage T3 or less, and a positive surgical margin was also significantly associated with poor survival. Overall, SCC associated with IP has a favorable DSS, early diagnosis and complete resection of lesions is required for a good prognosis. Furthermore, aggressive surgical approaches combined with postoperative adjuvant therapy seem to be effective in tumors at stage T4.

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

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

Human papillomavirus (HPV) and somatic EGFR mutations are essential, mutually exclusive oncogenic mechanisms for inverted sinonasal papillomas and associated sinonasal squamous cell carcinomas

Background

Inverted sinonasal (Schneiderian) papilloma (ISP) is a locally aggressive neoplasm often associated with sinonasal squamous cell carcinoma (SNSCC). While the etiology of ISP is not well understood, human papillomavirus (HPV) has been detected in a subset of cases. Our group recently identified activating somatic EGFR mutations in the majority of ISP and ISP-associated SNSCC. However, the relationship between EGFR mutations and HPV infection has not been explored.

Patients and methods

We evaluated 58 ISP and 22 ISP-associated SNSCC (including 13 patients with matched ISP/SNSCC samples), as well as 14 SNSCC without clinical or pathologic evidence of an associated ISP. Formalin-fixed, paraffin-embedded samples were evaluated for EGFR mutations using Sanger sequencing and for HPV infection using GP5+/GP6+ PCR. HPV subtyping based on the L1 sequence was done for HPV positive cases including temporally distinct tumors for four patients. Clinicopathologic data including progression free survival was also analyzed.

Results

All ISP and ISP-associated SNSCC demonstrated either an EGFR mutation or HPV infection. HPV and EGFR mutation were mutually exclusive in all cases of ISP-associated SNSCC and all but one ISP; this case was only weakly HPV positive, and analysis of a prior temporally distinct ISP specimen from this patient failed to show HPV infection, suggesting transient infection/incidental colonization. HPV subtypes in ISP and ISP-associated SNSCC were predominantly low-risk, in contrast with SNSCC without ISP association, which showed frequent high-risk HPV. All paired ISP and associated SNSCC samples demonstrated concordant HPV status and EGFR genotypes. ISP progression to SNSCC was significantly associated with the presence of HPV infection and the absence of an EGFR mutation (log-rank = 9.620, P = 0.002).

Conclusions

Collectively our data show that EGFR mutations and HPV infection represent essential, alternative oncogenic mechanisms in ISP and ISP-associated SNSCC.

Sinonasal inverted papilloma associated with small cell neuroendocrine carcinoma: A case report and literature review of rare malignancies associated with inverted papilloma

We report a rare case of sinonasal inverted papilloma (IP) associated with small cell neuroendocrine carcinoma (SNEC). To our knowledge, this is the first report to describe SNEC found during the treatment of sinonasal IP. Surgery and five cycles of cisplatin plus etoposide with concurrent intensity modulated radiation therapy were performed. Neither local recurrence nor distant metastasis was noted during 6 years of post-diagnostic follow-up. The prognosis of SNEC is very poor. Treatment planning for sinonasal IP should consider a possible association with this rare but aggressive malignancy, whose treatment is completely different from that of squamous cell carcinoma, a malignancy which is commonly associated with IP. We also performed a PubMed review of the literature to identify the incidence and pathological diagnosis of associated malignancy. Among a total of 5286 cases of sinonasal IP (61 studies), the incidence of associated malignancy was 8.02% in squamous cell carcinoma, 0.19% in transitional cell carcinoma, 0.04% in mucoepidermoid carcinoma, 0.02% in verrucous cell carcinoma and 0.02% in adenocarcinoma. The incidence of associated malignancy was significantly higher in East and Southeast Asia (11.0%) and North America (10.4%) than in Europe (3.9%) (p=0.04 and p=0.03, respectively; T-test).

Inflammation and the Pathogenesis of Inverted Papilloma

Background

Despite existing clinical and histopathological evidence, the role of inflammation in the pathogenesis of inverted papilloma (IP) is not well understood. The goal of this study was to describe the inflammatory cell component present in sinonasal papilloma (SP), with the intention of further defining the existence of inflammation in IP and perhaps gaining insight into IP pathophysiology.

Methods

Computerized database analysis was performed to identify all patients with SP who underwent surgery at the Cleveland Clinic Foundation between 1995 and 2001. Histopathological features of all SP were reviewed and semiquantitative analysis of the inflammatory cells present was performed. IP was histopathologically graded into four categories by the extent of inflammatory infiltrate and cellular atypia. Statistical analysis of the inflammatory cell component present in the epithelial layer of exophytic papilloma and IP was performed.

Results

SP was classified into three types: cylindrical papilloma (5% [2/41]), exophytic squamous papilloma (34% [14/41]), and IP (61% [25/41]). Twenty-eight instances of IP in 25 patients were identified. Altogether, 11% were grade I (3/28), 54% were grade II (15/28), 25% were grade III (7/28), and 11% were grade IV (3/28). The inflammatory cell population was significantly greater in IP compared with other SPs and greater in grades I and II IP when compared with grade III and IV IP.

Conclusion

Inflammatory cells were identified as a significant cell population in IP, whereas it was less commonly encountered in other forms of SP. The proposed IP staging system may serve as the foundation for improved understanding of IP and, ultimately, may help to predict recurrence or apparent malignant transformation.

Clinical features of nasal and sinonasal inverted papilloma associated with malignancy

OBJECTIVE

Nasal and sinonasal inverted papilloma (IP) are rare benign tumors and have the potential to exhibit malignancy in approximately 10% of cases. This study aimed to analyze the clinical features of IP associated with malignancy. Furthermore, we reviewed our therapeutic strategy and the clinical course of malignant IP.

METHODS

Overall, 70 patients with IP at our institution were retrospectively analyzed from April 2006 to December 2015; of these, six (9%) had associated malignancy. Data was collected on sex, age, presenting symptoms (nasal bleeding, rhinorrhea, facial or cheek pain, and nasal obstruction), bone destruction, and extent of disease on CT and MRI. Categorical data of patients with and without malignancy were compared using the chi-square test. A p value of <0.05 was considered statistically significant. Our therapeutic strategy for IP with malignancy, particularly the surgical procedure, i.e., the external incision or the endoscopic nasal approach, varied based on when the carcinoma was detected. In addition, we considered postoperative radiation therapy depending on histological examination.

RESULTS

Nasal bleeding (p<0.001), pain (p=0.040), bone destruction (p<0.001), and extent of disease (p=0.026) on CT and MRI findings were significantly associated with malignancy. Carcinoma was diagnosed preoperatively in two (33%) and postoperatively in four patients (67%). We operated five patients (one case was not treated because of end-stage pancreatic cancer). Two patients underwent endoscopic sinus surgery (ESS) alone, two ESS plus Denker's method, and one ESS plus anterior craniotomy. Three patients underwent surgery only, and two patients received postoperative radiotherapy. The median follow-up period was 69.3 months. One patient died of the disease and the remaining patients are alive without recurrence.

CONCLUSION

For IP patients exhibiting these clinical findings preoperatively, we should suspect complication with malignancy and plan a treatment. Even if postoperative histology does not confirm malignancy, we should ensure careful observation because of metachronous malignant transformation or the possibility to overlook small malignant lesions. Our result suggests that our strategy for malignant IP could be a reasonable option.

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

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

OSPs and ESPs and ISPs, Oh My! An Update on Sinonasal (Schneiderian) Papillomas

Sinonasal (Schneiderian) papillomas are benign neoplasms that arise in the sinonasal tract. Since their initial descriptions, sinonasal papillomas have triggered debate regarding their classification, etiology, rate or predictors of malignant transformation, and other issues. While significant strides have been made in recent years, there are still aspects of sinonasal papillomas that remain unclear even now. This review will serve to update the practicing pathologist on the current understanding of sinonasal papillomas.

Transcriptionally Active High-Risk Human Papillomavirus is Not a Common Etiologic Agent in the Malignant Transformation of Inverted Schneiderian Papillomas

The role of human papillomavirus (HPV) as an etiologic and transformational agent in inverted Schneiderian papilloma (ISP) is unclear. Indeed, reported detection rates of HPV in ISPs range from 0 to 100%. The true incidence has been confounded by a tendency to conflate high- and low-risk HPV types and by the inability to discern biologically relevant from irrelevant HPV infections. The recent development of RNA in situ hybridization for high-risk HPV E6/E7 mRNA now allows the direct visualization of transcriptionally active high-risk HPV in ISP, providing an opportunity to more definitively assess its role in the development and progression of ISPs. We performed p16 immunohistochemistry and high-risk HPV RNA in situ hybridization on 30 benign ISPs, 7 ISPs with dysplasia, 16 ISPs with carcinomatous transformation, and 7 non-keratinizing squamous cell carcinomas (SCCs) with inverted growth that were unassociated with ISP. Transcriptionally active HPV was not detected in any of the 52 ISPs including those that had undergone carcinomatous transformation, but it was detected in two of seven (29%) non-keratinizing SCCs that showed inverted growth. There was a strong correlation between high-risk HPV RNA in situ hybridization and p16 immunohistochemistry (97%; p < 0.01). These results indicate that transcriptionally active high-risk HPV does not play a common role in either the development of ISP or in its transformation into carcinoma.

Survival outcomes after endoscopic resection for sinonasal squamous cell carcinoma arising on inverted papilloma

BACKGROUND

Sinonasal inverted papillomas (IPs) can be associated synchronously or metachronously to invasive squamous cell carcinoma (SCC) in 5% to 10% of cases. The purposes of the present study were to analyze the outcomes of patients with sinonasal SCC arising from inverted papilloma (IP-SCC) treated through an endoscopic approach and review the pertinent literature.

METHODS

The medical records of all patients treated for IP-SCC between 1997 and 2014 at 2 referral centers following a uniform policy were retrospectively analyzed.

RESULTS

Thirty-four patients fulfilled the inclusion criteria. The 5-year overall survival (OS), disease-specific survival (DFS), and recurrence-free survival (RFS) rates were 66.8 ± 0.99%, 71.2 ± 0.96%, and 73.1 ± 0.82%, respectively. Multivariate analysis revealed that the advanced pT classification (pT3 or greater), the high-grade of tumoral differentiation, the cranioendoscopic approach, and the recurrence of disease impacted negatively on survival rates.

CONCLUSION

The endoscopic approach provides encouraging oncologic outcomes for sinonasal IP-SCC, comparable to those observed with traditional external approaches while minimizing morbidity for patients. © 2016 Wiley Periodicals, Inc. Head Neck 38: 1708-1716, 2016.

Endoscopic Modified Medial Maxillectomy for Resection of an Inverted Papilloma Originating from the Entire Circumference of the Maxillary Sinus

For treatment of a sinonasal inverted papilloma (IP), it is essential to have a definite diagnosis, to identify its origin by computed tomography (CT) and magnetic resonance imaging (MRI), and to select the appropriate surgical approach based on the staging system proposed by Krouse. Recently, a new surgical approach named endoscopic modified medial maxillectomy (EMMM) was proposed. This approach can preserve the inferior turbinate and nasolacrimal duct. We successfully treated sinonasal IP with EMMM in a 71-year-old female patient. In this patient, the sinonasal IP originated from the entire circumference of the maxillary sinus. EMMM is not a difficult procedure and provides good visibility of the operative field. Lacrimation and empty nose syndrome do not occur postoperatively as the nasolacrimal duct and inferior turbinate are preserved. EMMM is considered to be a very favorable approach for treatment of sinonasal IP.

High-Frequency Targetable EGFR Mutations in Sinonasal Squamous Cell Carcinomas Arising from Inverted Sinonasal Papilloma

Inverted sinonasal papilloma (ISP) is a locally aggressive neoplasm associated with sinonasal squamous cell carcinoma (SNSCC) in 10% to 25% of cases. To date, no recurrent mutations have been identified in ISP or SNSCC. Using targeted next-generation sequencing and Sanger sequencing, we identified activating EGFR mutations in 88% of ISP and 77% of ISP-associated SNSCC. Identical EGFR genotypes were found in matched pairs of ISP and associated SNSCC, providing the first genetic evidence of a biologic link between these tumors. EGFR mutations were not identified in exophytic or oncocytic papillomas or non-ISP-associated SNSCC, suggesting that the ISP/SNSCC spectrum is biologically distinct among sinonasal squamous tumors. Patients with ISP harboring EGFR mutations also exhibited an increased progression-free survival compared with those with wild-type EGFR. Finally, treatment of ISP-associated carcinoma cells with irreversible EGFR inhibitors resulted in inactivation of EGFR signaling and growth inhibition. These findings implicate a prominent role for activating EGFR mutations in the pathogenesis of ISP and associated SNSCC and rationalize consideration of irreversible EGFR inhibitors in the therapy of these tumors.

Transcriptional activity of HPV in inverted papilloma demonstrated by in situ hybridization for E6/E7 mRNA

OBJECTIVE

Assess human papilloma virus (HPV) transcriptional activity in inverted Schneiderian papillomas (IPs).

STUDY DESIGN

Case series with chart review.

SETTING

Academic tertiary care center.

SUBJECTS AND METHODS

Retrospective clinicopathologic review of 19 cases of IP in patients undergoing surgical excision from 1995 to 2013 at Mayo Clinic in Rochester, Minnesota. Surgical pathology archival material was histopathologically reviewed using hematoxylin and eosin-stained slides. Formalin-fixed, paraffin-embedded material from each case was evaluated for p16 expression using immunohistochemistry as well as HPV DNA and E6/E7 messenger RNA (mRNA) transcription using polymerase chain reaction (PCR) and in situ hybridization (via RNAscope technology), respectively.

RESULTS

Eight patients were female (42%), with an average age of 53 years (range, 23-82 years). Three demonstrated malignancy, and 5 subsequently recurred. Average follow-up was 49 months (range, 0-200 months), and 1 patient died from squamous cell carcinoma arising from the IP. RNAscope detected HPV mRNA transcripts exclusively within IP in 100% of cases; however, in 11 patients (58%), less than 1% of cells exhibited transcriptional activity. Only 2 of 19 cases (11%) demonstrated mRNA activity in 50% or more cells. HPV DNA was detected in only 2 specimens by PCR.

CONCLUSIONS

This study reveals wide prevalence but limited transcriptional activity of HPV in IP. No correlation between HPV transcriptional activity and progression, recurrence, or malignant transformation was identified. These data suggest that transcription of HPV may contribute to the pathogenesis of IP, but prospective data are needed to definitively demonstrate this connection. These results also suggest that RNAscope may be more sensitive than PCR in detecting HPV activity in IP.

Radiation therapy for sinonasal inverted papilloma

PURPOSE

We retrospectively reviewed long-term outcomes of patients with inverted papilloma (IP) treated with radiation therapy at our institution.

METHODS AND MATERIALS

From 1969 to 2008, 13 patients with advanced or recurrent IP (n = 12) or cylindrical papilloma (n = 1) were treated with radiation therapy. The median age at radiation therapy was 53 years old (range, 32-84). Nine patients received postoperative radiation therapy, 3 received definitive radiation therapy, and 1 received preoperative radiation therapy. Of the 10 patients treated with combined-modality treatment, 1 underwent craniofacial resection and 9 underwent open resection. Eight patients, 4 patients, and 1 patient received once-daily fractionation, twice-daily fractionation, and planned split-course radiation therapy, respectively, to a median dose of 65 Gy (range, 45.3-70.4 Gy).

RESULTS

The median follow-up was 16.2 years. Actuarial 15-year overall and cause-specific survival rates were 62% and 82%. Fifteen-year actuarial local and regional control rates were 45% and 73%. Fifteen-year local-regional control rates for IP alone and IP associated with squamous cell carcinoma (IP-SCC) at the time of treatment were 80% and 16%. Fifteen-year overall survival rates for IP alone and IP-SCC were 40% and 50%. The only severe treatment complication was a grade 3 central nervous system radionecrosis. The most common grade 1-2 toxicities were mucositis (61%), pain (46%), conjunctivitis (31%), xerostomia (31%), epiphora (31%), and anorexia (31%).

CONCLUSIONS

While surgery is the primary treatment for IP, radiation therapy should be considered in patients with SCC, multiply recurrent IPs, and incompletely resectable IP. Radiation therapy is associated with a relatively low risk of severe complications. Despite more aggressive treatment, local failure remains a considerable challenge.

Nasal endoscope: an armamentarium in the management of sinonasal inverted papilloma

Sinonasal inverted papillomas (SIP) are unique group of locally aggressive benign neoplastic lesions arising from mucosa of sinonasal tract with potential for recurrences and known association with squamous cell carcinoma in 5-15 % of cases. This study was conducted was to assess the efficacy and usefulness of the nasal endoscope in treating SIP. We reviewed 28 biopsy proven cases of SIPs that were treated at our hospital between June 2009 and September 2013. Average patient age was 46 years. Fourteen were treated by transnasal endoscopic excision of tumor with noted recurrence of 21.43 %. Thirteen were treated by endoscopic assisted open surgery which had 23 % recurrence. Three patients had malignant inverted papillomas, of whom two (7 %) were found to have synchronous squamous cell carcinoma and one (3.6 %) had metachronous squamous cell carcinoma. No evidence of recurrence was found in rest during our follow up. The endoscopic approach is the preferred method for the treatment of the majority of inverted papillomas. Powered instrumentation is extremely useful to achieve good results. Although significant number of cases was done by external approach by lateral rhinotomy, the endoscopic assistance is required to ensure complete removal of the tumour to reduce the recurrence rates. Close follow up of the patient for a longer period of time is necessary for the early detection of recurrence and to allow for surgical salvage.

[Inverted papilloma: a retrospective study of 22 cases]

Le papillome inversé est une tumeur bénigne naso-sinusienne rare, marquée par une forte agressivité locale, un taux élevé de récidive après chirurgie et un risque imprévisible d'association à un carcinome épidermoïde. Il s'agit d'une étude rétrospective de 22 cas de papillome inversé, colligés entre janvier 2000 et décembre 2012 au service d'oto-rhino-laryngologie et chirurgie cervico-faciale de l'hôpital militaire Avicenne de Marrakech. L'objectif de ce travail est d’étudier le profil épidémiologique, clinique, endoscopique, radiologique, thérapeutique et évolutif du papillome inversé. Le sex-ratio a été de 3,7 en faveur du sexe masculin avec une moyenne d’âge de 44 ans et un pic de fréquence entre la quatrième et la cinquième décade. Les symptômes cliniques ont été dominés par l'obstruction nasale. Le bilan radiologique faisant appel au couple TDM et IRM naso-sinusiennes constitue un moyen essentiel pour le diagnostic positif et dans choix de la technique opératoire. La voie vestibulaire sous labiale de Rouge Denker a été utilisée chez 4 patients, 12 patients ont bénéficié d'une chirurgie endoscopique endonasale et 6 patients d'une combinaison des deux voies précédentes. Cinq patients ont eu une récidive du papillome inversé, après un délai moyen de 26 mois.

Sinonasal inverted papilloma: prognostic factors with emphasis on resection margins

Objective We review our institution's experience with the treatment of inverted papilloma (IP) with emphasis on the implications of surgical margins for disease control. Design Retrospective chart review of patients with IP treated at the University of Michigan from 1996 to 2011. Setting Tertiary care center. Participants Patients undergoing surgical resection with curative intent for IP. Main Outcome Measures Overall survival, disease-specific survival, and locoregional control were used as main outcome measures. Results We studied 129 patients including 19 with carcinoma arising from IP. Disease-free rates at 2, 3, and 5 years were 79.7%, 77.9%, and 61%, respectively. Overall, 10 of 18 recurrences were detected > 2 years from follow-up, with recurrences detected up to 8 years from surgery. For benign disease, obtaining tissue margins outside of the primary specimen for margin control did not affect disease control rates. Conclusion IP is a disease that requires significant follow-up periods beyond 2 years. For IP without carcinogenesis, acquiring margins outside of the tumor specimen did not appear to affect disease control rates in this study. No clear predictors of malignancy were seen in this study, which highlights the need for further research to predict this phenomenon.

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

Schneiderian papilloma (SP) are uncommon tumors with malignant transformation even less common. The histologic criteria to define malignant transformation are not well developed nor is the immunohistochemical profile reported in a large series of carcinomas. 20 cases of malignant transformation of SP included 7 females and 13 males, aged 38-86 years (mean 60.7 years). Patients presented most frequently with a mass (n = 11) and obstructive symptoms (n = 7), present for 38.7 months (mean). Most patients had no previous history of SP (n = 13); metachronous carcinoma was identified in 7 patients an average of 34.4 months after the first diagnosis of SP, with 1-4 recurrences of SP. With a mean size of 4.1 cm, the majority of tumors involved a combination of more than one anatomic site (n = 10), followed by the maxillary sinus only (n = 5) or nasal cavity only (n = 3). Histologically, 17 were inverted and 3 exophytic type SP. There were 17 squamous cell carcinomas, 2 mucoepidermoid carcinomas and 1 sinonasal undifferentiated carcinoma, comprising from 10 to 95 % of the tumor volume. Malignant histologic features included atypical mitoses, necrosis, bone invasion, lymphovascular invasion, decreased transmigrating neutrophils, paradoxical maturation, dyskeratosis and/or perineural invasion (n = 3). Patients tended to present with advanced stage (n = 14, Stage III and IV). Immunohistochemical studies showed positive reactions in the malignancies for CK5/6 (86 %), p63 (86 %), CK7 (luminal, 50 %), p53 (83 %), and p16 (25 %). In situ hybridization detected human papillomavirus in 26 %. Surgery was often accompanied by radiation therapy (n = 13), with a mean of 2.4 years of follow-up. Five patients developed a recurrence between 0.8 and 3.3 years. Carcinomas ex-SP are less common and are associated with better outcome than previously reported. Patients tend to present with a synchronous carcinoma, developing in an inverted type SP, with squamous cell carcinoma the most common malignancy. Development of metachronous carcinomas ex-SP was always preceded by SP recurrence in this series.

Epidermal growth factor receptor, p16, cyclin D1, and p53 staining patterns for inverted papilloma

BACKGROUND

The aim of this study was better characterize the staining patterns of inverted papilloma (IP) with and without carcinoma by performing immunohistochemistry for p16, epidermal growth factor receptor (EGFR), p53, and cyclin D1 antibodies in a large patient cohort.

METHODS

A total of 162 IP specimens were collected from 147 patients treated at the University of Michigan between 1996 and 2011. Twenty-two specimens contained carcinoma. Tumor was extracted for construction of 2 tissue microarrays and stained for p16, EGFR, p53, and cyclin D1. Tumor staining intensity and percentage staining were scored.

RESULTS

Benign disease was positive for p16 in 64%, EGFR in 50%, p53 in 30%, and cyclin D1 in 76%. IP with carcinomatous degeneration was positive for p16 in 14%, EGFR in 71%, p53 in 62%, and cyclin D1 in 76%. The differences in staining positivity between benign and malignant disease reached significance for p16 and p53 only. Mean percentage staining by tumor surface area for IP and IP with carcinoma was 12% vs 7% for p16 (no statistical significance [NS]), 20% vs 34% for EGFR (NS), 4% vs 24% for p53 (p < 0.001), and 17% vs 21% for cyclin D1 (NS).

CONCLUSION

Important characteristic staining pattern for IP with and without carcinoma are highlighted in this study. Unlike recent trends in human papilloma virus (HPV)-related head and neck malignancies, low expression of p16 is a marker for malignancy in this series. Positive staining for p53 correlates with the development of carcinoma in IP.

[Sinonasal inverted papilloma: 43 cases]

PURPOSE

Inverted papilloma (IP) is a common epithelial tumor arising from the nasal vault. The aim of our study was to evaluate the advantages, the results and the limits in the treatment of this tumor.

PATIENTS AND METHOD

Retrospective study of 43 patients over the period 1989-2009.

RESULTS

The mean age was 53.3 years. We found a maxillary sinus extension in 40 cases and ethmoidal extension in 27 cases. Twenty-nine patients were treated through an endoscopic endonasal approach. A vestibular approach was used in three patients. A paralateral nasal approach was used for 12 cases. We observed a recurrence in 9.3% of the all cases.

CONCLUSION

The treatment of IP is surgical. Their high potential of local aggressiveness, fear of recurrence and the possibility of the occurrence of a malignancy require radical treatment.

Skull base inverted papilloma: a comprehensive review

Skull base inverted papilloma (IP) is an unusual entity for many neurosurgeons. IP is renowned for its high rate of recurrence, its ability to cause local destruction, and its association with malignancy. This paper is a comprehensive review of the reports, studies, and reviews published in the current biomedical literature from 1947 to September 2010 and synthesize this information to focus on its potential invasion to the base of the skull and possible intradural extension. The objective is to familiarize the clinician with the different aspects of this unusual disease. The role of modern diagnostic tools in medical imaging in order to assess clearly the limits of the tumors and to enhance the efficiency and the safety in the choice of a surgical approach is pointed out. The treatment guidelines for IP have undergone a complex evolution that continues today. Radical excision of the tumour is technically difficult and often incomplete. Successful management of IP requires resection of the affected mucosa which could be achieved with open surgery, endoscopic, or combined approach. Radio and chemotherapy were used for certain indications. More optimally research would be a multicenter randomized trials with large size cohorts.

Inverted papilloma of nose with orbital involvement and malignant transformation

We report two cases of inverted papilloma of nose with malignant transformation and orbital involvement in 60 year and 73 year male patients from Nepal. Medial maxillectomy and orbital exenteration were done in both cases. Histo- pathological examination showed areas of squamous cell carcinoma in inverted papilloma in both of the cases.The dilemma of diagnosis and treatment is discussed with review of literature.

Inverted papilloma of the palate with malignant transformation

The inverted papilloma is a unilateral sinonasal benign tumor which is characterized by aggressive local invasion, high recurrence rate, and transformation into malignancy. The etiology of inverted papilloma is still unknown. Possible causes include allergy, chronic sinusitis, occupational exposure to dusts and aerosols, tobacco, and viral infections. Treatment is complete surgical excision and close postoperative follow-up is necessary. Here we report a case of inverted papilloma arising from the hard palate with malignant transformation in a 41-year-old female. Clinical and histological features and treatment are discussed with the review of literature.

Expression pattern of IQGAP1 in sinonasal inverted papillomas and squamous cell carcinomas

OBJECTIVES/HYPOTHESIS

The scaffold protein IQGAP1 is a ubiquitously expressed 190 kDa protein that participates in protein-protein interactions, integrating diverse signaling pathways. In this study, we examined the expression of IQGAP1 in sinonasal inverted papillomas (IP) and sinonasal squamous cell carcinomas (SCC), which include IP with SCC (IPcSCC) and SCC alone. We also tried to elucidate whether the amount of IQGAP1 expression is related with any clinicopathologic features of sinonasal SCCs.

STUDY DESIGN

This was a retrospective study.

METHODS

The expression of IQGAP1 was analyzed by means of immunohistochemistry. The degrees of IQGAP1 expression and subcellular localization (rim formation) were analyzed with respect to the following clinicopathologic variables: age, gender, T stage, histologic differentiation, local recurrence, and distant metastasis.

RESULTS

The expression of IQGAP1 was significantly higher in patients with IPcSCC (3.62 ± 0.14), and SCC (2.93 ± 0.34) compared with IP (1.43 ± 0.26). The rim formation scale was significantly higher in IPcSCC (2.39 ± 0.24) compared with IP (1.68 ± 0.15). Distant metastasis in patients with SCC significantly correlated with an increased IQGAP1 rim formation (p = 0.011). Histologic differentiation was also significantly correlated with a positive staining scale for IQGAP1 in IPcSCCs (p = 0.038).

CONCLUSION

These results indicated that IQGAP1 expression is associated with both the histologic differentiation of IPcSCCs and is present in SCC cases where distant metastasis has occurred.

Expression pattern of apurinic/apyrimidinic endonuclease in sinonasal squamous cell carcinoma

OBJECTIVE

To evaluate the apurinic/apyrimidinic endonuclease 1 (APE1) expression in sinonasal squamous cell carcinomas (SCC) and to examine the correlation between APE1 expression patterns and various clinicopathological factors associated with sinonasal SCC that include SCC with inverted papilloma (SCCwIP) and SCC alone.

STUDY DESIGN

Case-control study.

SETTING

Chungnam National University Hospital.

SUBJECTS AND METHODS

The expressions of APE1 were analyzed by means of immunohistochemistry in 30 sinonasal SCC, including 14 SCC patients associated with IP and 16 patients with SCC alone. A total of 19 patients who had been diagnosed with chronic rhinosinusitis with nasal polyposis and who required endoscopic sinus surgery were used as the control group. The degrees of APE1 expression were analyzed with respect to the following clinicopathologic variables: age, sex, T stage, histologic differentiation, distant metastasis, and recurrence.

RESULTS

Cytoplasmic staining of APE1 was significantly higher in SCC compared with SCCwIP (68.75% vs 14.29%). Cytoplasmic staining of APE1 was significantly associated with T stage (P = .044) in SCC and histologic grade (P = .0025) in sinonasal SCC. Nuclear staining of APE1 was significantly associated with distant metastasis (P = .022) in SCC.

CONCLUSION

These results suggest that the nuclear and cytoplasmic expression of APE1 may be related to tumor invasiveness and prognosis in sinonasal SCC. The suppression of APE1 expression can potentially be a new target for future sinonasal SCC therapies.

Clinical and histologic features of inverted papilloma-associated malignancy

The objectives of the study were to analyze the clinical features of inverted papillomas (IP) associated with malignancy and to evaluate the correlation of tumor stage, survival and histolologic features. We conducted a retrospective review of 18 IP associated with malignancy patients. In addition, we compared histopathologic characteristics (tumor differentiation and malignant cell proportion) with clinical outcomes. Eleven of the tumors were present on the nasal cavity and 7 on the maxillary sinus. The rates of synchronous and metachronous malignancy were 10.1 and 1.1%, respectively. The disease-free survival rate was 83.3%. The tumors were staged as T1 (5/18), T2 (2/18), T3 (8/18), and T4 (3/18). According to the percentage of the malignant cell in the entire tumor tissue, 4 patients (22%) were in grade I, 4 patients (22%) were in grade II, 3 patients (17%) were in grade III, and 7 patients (39%) were in grade IV. There was no relationship between recurrence- and/or disease-free survival and histologic findings including tumor differentiation and malignant proportion. IP-associated malignancy tends to occur synchronously and have more favorable prognosis compared to other sinonasal malignancy. Furthermore, the proportion of malignant cell to IP and tumor stage seems not to affect the clinical outcome of IP-associated malignancy.

Select Neoplasms of the Sinonasal Tract

The sinonasal tract (SNT) includes the nasal cavity and paranasal sinuses (maxillary, ethmoid, frontal, and sphenoid) and may give rise to a variety of nonneoplastic and neoplastic proliferations, including benign and malignant neoplasms. The benign neoplasms of the SNT include epithelial neoplasms of surface epithelial origin, minor salivary gland origin, and mesenchymal origin. The spectrum of malignant neoplasms of the SNT includes epithelial malignancies, sinonasal undifferentiated carcinoma, malignant salivary gland neoplasms, neuroectodermal neoplasms, neuroendocrine neoplasms, melanocytic neoplasm, and sarcomas. This article concentrates on some of the more common types of benign and malignant neoplasms.

Sinonasal inverted papilloma associated with squamous cell carcinoma

Background

The aims of the study were to review single-institution experiences with sinonasal inverted papilloma associated with squamous cell carcinoma (IP/SCC), to analyze the presence of human papillomavirus (HPV) and to evaluate the role of radiotherapy.

Patients and methods

Five patients with IP/SCC were identified in the prospective institutional databases (1995–2005) and HPV status was determined in all five tumors.

Results

Four out of five patients had T3-4 tumors; no nodal involvement was seen in any of them. Four patients had curative surgery, supplemented in three of them with radiotherapy. Debulking surgery was performed in the patient with a non-resectable tumor followed by radical radiotherapy. Tumor was controlled locally in three patients at 8, 46 and 58 months post-surgery. Local failure occurred in two patients: after endoscopic resection of a T1 tumor (the recurrent tumor was successfully salvaged with additional surgery) and in a patient with an inoperable tumor. No regional or distant metastases occurred. HPV status was determined in all five tumors and three of them were found positive for HPV type 11.

Conclusions

In operable sinonasal IP/SCC, upfront surgery and postoperative radiotherapy to the tumor bed with dose levels comparable to those used for invasive SCC are recommended. For non-resectable disease, radical radiotherapy to a dose of 66–70 Gy could be of benefit.

Schneiderian carcinoma developing in an inverted papilloma of the palatine tonsil: an unusual case

Schneiderian papillomas are among the most common benign tumors of the nose and paranasal sinuses. These lesions frequently originate in the lateral nasal wall, and they have a tendency toward recurrence and malignant transformation. Carcinomas arise in association with schneiderian papillomas in approximately 10% of cases. Outside the sinonasal tract, the ectopic occurrence of a schneiderian papilloma is extremely rare. We describe the case of a 52-year-old man with an invasive schneiderian carcinoma that arose within an inverted papilloma in the palatine tonsil. To the best of our knowledge, no such case has been previously reported in the English-language literature.

Sinonasal carcinoma associated with inverted papilloma: a report of 16 cases

OBJECTIVES

To analyse the characteristics and outcome of patients with carcinoma associated with inverted papilloma, and find predictors of associated malignancy.

METHODS

The medical records of 228 patients who were diagnosed with IP between January 1990 and December 2010 were retrospectively reviewed. Out of 228 patients, 16 were also diagnosed with carcinoma. We evaluated their clinical characteristics, treatment modalities, and survival outcomes.

RESULTS

The incidence of carcinoma associated with IP was 7.0%. Fourteen were synchronous carcinomas and two were metachronous. Tumours arising inside the frontal sinus or the frontoethmoidal recess were more likely to be associated with carcinoma. Patients who had a stage of T2 or less had a much better outcome than those who had a stage of T3 or greater (disease-free period, 84.8 months vs. 5.7 months, p<0.001).

CONCLUSION

Tumours originating in the frontal sinus or frontoethmoidal recess have a tendency to be associated with carcinoma. As most (87.5%) of the carcinomas were diagnosed at the same time as the inverted papilloma, complete histological examination of the whole excised tumour is warranted because early diagnosis and treatment is essential as T2 and lower stage carcinomas had a strikingly better prognosis than T3 and higher stage carcinomas.

Inverted papilloma of the middle ear: a case report and review of the literature

Papilloma of the middle ear is extremely rare; to our knowledge there have been only 9 reports (13 cases) in the literature. Aggressive surgical excision is the only curative treatment and radiation therapy is necessary if there is evidence of focal squamous cell carcinoma. We describe a case of a 65-year-old male with inverted papilloma of the middle ear. The tumor was surgically resected by radical tympanomastoidectomy, and we provided postoperative radiation therapy. There has been no evidence of recurrence to date. We discuss the clinical presentation, diagnosis, and treatment of this case and present a review of the literature.