The sinonasal tract: another potential "hot spot" for carcinomas with transcriptionally-active human papillomavirus

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.

Aspergillus Species and Human Papillomavirus Infections in Epithelial Tumors of Nasal and Paranasal Cavities

Background: There are diverse lesions originating from the paranasal sinuses and nasal cavity. Tobacco use, alcohol consumption, and malnutrition have been identified to play a role in the development of head and neck carcinomas. Recently, fungi and viruses have been recognized as potential causes of nasal cavity and paranasal tumors. Objectives: This study aimed at specifying the prevalence of Aspergillus and human papillomavirus (HPV) infections in the epithelial tumors of nasal cavity and paranasal sinuses. Methods: In this cross-sectional study, 57 paraffin-embedded tissue samples of malignant and benign lesions of the paranasal sinuses and nasal cavity were evaluated for the presence of Aspergillus and HPV DNA by nested polymerase chain reaction (nPCR) technique with specific primers. Results: Despite the absence of angular hyphae (acute angle) of the fungus on histopathological slides, overall, 10 (17.54%) out of 57 paraffin-embedded samples were found to be positive for Aspergillus species. However, HPV-DNA was not found in any of the samples. Conclusions: Our data suggest that fungal infections (especially aspergillosis) as an etiological factor can be contributed to the development of sinonasal cancer and, therefore, they should be considered in the management of patients with sinonasal cancer. In addition, PCR can provide an alternative to culture-dependent identification methods.

Top 10 Basaloid Neoplasms of the Sinonasal Tract

BACKGROUND

Basaloid neoplasms of the sinonasal tract represent a significant group of tumors with histological overlap but often with different etiologies (i.e., viral, genetics), clinical management, and prognostic significance.

METHODS

Review.

RESULTS

"Basaloid" generally refers to cells with coarse chromatin in round nuclei and sparse cytoplasm, resembling cells of epithelial basal layers or imparting an "immature" appearance. Tumors with this characteristic in the sinonasal tract are represented by a spectrum of benign to high-grade malignant neoplasms, such as adenoid cystic carcinoma, NUT carcinoma, sinonasal undifferentiated carcinoma, SWI/SNF complex-deficient carcinomas, and adamantinoma-like Ewing sarcoma.

CONCLUSION

In some instances, histology alone may be sufficient for diagnosis. However, limited biopsy material or fine-needle aspiration specimens may be particularly challenging. Therefore, often other diagnostic procedures, including a combination of histology, immunohistochemistry (IHC), DNA and RNA testing, and molecular genetics are necessary to establish an accurate diagnosis.

Recurrence rates of de-novo versus inverted papilloma-transformed sinonasal squamous cell carcinoma: a meta-analysis

Background: There is a paucity of reporting on recurrence patterns of de-novo sinonasal squamous cell carcinoma (DN-SCC) and inverted-papilloma-transformed sinonasal squamous cell carcinoma (IP-SCC). Method: A systematic literature review queried studies comparing recurrence patterns in patients with both DN-SCC and IP-SCC. Primary outcomes included local and regional recurrence and rates of distant metastasis. Of the 595 studies screened, eight were included. Results: Patients with DN-SCC had significantly higher rates of positive margins, advanced T classification (T3/T4), treatment with chemotherapy and radiotherapy. There were no significant differences in local recurrence or regional recurrence. Overall risk of distant metastasis was lower in IP-SCC. DN-SCC, compared to IP-SCC, is more likely to present with advanced TNM classification and have positive margins after surgical resection, which may affect rates of distant metastasis and recurrence. Conclusions: The findings in this study suggest IP-SCC may be a less aggressive malignancy compared to DN-SCC, with the possibility of a reduced role for adjuvant therapy in IP-SCC. Further studies are required to better understand differences in tumor biology and treatments strategies between IP-SCC and DN-SCC.

Molecular Detection Methods in HPV-Related Cancers

Human papillomavirus (HPV) is responsible for most cervical cancers and some head and neck cancers, including oropharyngeal squamous cell carcinoma and sinonasal carcinoma. Cervical cancer is commonly diagnosed by liquid-based cytology, followed by HPV testing using commercially available DNA polymerase chain reaction (PCR), p16 immunohistochemistry (IHC), or DNA/RNA in situ hybridization. HPV in head and neck cancers is commonly diagnosed by p16 IHC or by RT-qPCR of HPV-16 E6 and E7 oncoproteins. Droplet digital PCR has been reported as an ultrasensitive and highly precise method of nucleic acid quantification for biomarker analysis and has been used to detect oncogenic HPV in oropharyngeal and cervical cancers.

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

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

DEK-AFF2 Carcinoma of the Sinonasal Region and Skull Base: Detailed Clinicopathologic Characterization of a Distinctive Entity

A novel DEK-AFF2 fusion was recently reported in 4 nonkeratinizing squamous cell carcinomas of the sinonasal region and skull base, including 1 with exceptional response to immunotherapy, but it is not yet clear if this rearrangement defines a unique clinicopathologic category or represents a rare event. This study aims to characterize a larger cohort of carcinomas with DEK-AFF2 fusions to assess whether they truly constitute a distinctive entity. Among 27 sinonasal and skull base nonkeratinizing squamous cell carcinoma that were negative for human papillomavirus and Epstein-Barr virus, RNA sequencing identified DEK-AFF2 fusions in 13 cases (48%). Nine were centered in the nasal cavity, 2 in the middle ear/temporal bone, 1 in the nasopharynx, and 1 in the orbit. These tumors displayed recurrent histologic features including (1) complex endophytic and exophytic, frequently papilloma-like growth, (2) transitional epithelium with eosinophilic to amphophilic cytoplasm, (3) absent or minimal keratinization with occasional compact keratin pearls, (4) monotonous nuclei, and (5) prominent tumor-infiltrating neutrophils or stromal lymphocytes. This appearance not only overlaps with high-grade basaloid sinonasal carcinomas but also with benign papillomas and tumors reported as low-grade papillary Schneiderian carcinoma. However, DEK-AFF2 carcinomas showed frequent local recurrence, cervical lymph node metastases, and distant metastasis with 2 deaths from disease, confirming they are aggressive malignancies despite relatively bland histology. Overall, the distinctive molecular, histologic, and clinical features of DEK-AFF2 carcinomas suggest they represent a unique entity in the sinonasal region. This tumor merits increased pathologic recognition to better understand its prognostic and therapeutic implications.

Cancer of the Paranasal Sinuses

Sinonasal malignancies rare and pathologically diverse and make up <1% of all malignancies. Due to their anatomical location, they can cause significant morbidity with involvement of surrounding critical structures. They often present at a late stage with insidious onset of symptoms. Treatment of sinonasal malignancies is challenging and they often require a multimodality approach with surgery, radiation, and chemotherapy. Outcomes are poor with 5-year overall survival around 32%, but this varies greatly depending on histologic subtype. There is an urgent need for more randomized controlled trials to better define the appropriate therapeutic regimens and to improve clinical outcomes.

Sine Qua Non: Sinonasal Inverted Papilloma

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

Updates in the cause of sinonasal inverted papilloma and malignant transformation to squamous cell carcinoma

PURPOSE OF REVIEW

The purpose of this study was to give an overview of recently published articles investigating the cause of inverted papilloma and possible mechanisms mediating malignant transformation into squamous cell carcinoma (SCCa).

RECENT FINDINGS

Inverted papilloma is a sinonasal tumour that is benign in nature, but has a tendency for local invasion, recurrence and malignant degeneration. Its pathogenesis has not been elucidated and the etiological role for human papillomavirus virus (HPV) has been controversial. Recent reports have varied in detection method (mRNA ISH, DNA ISH and PCR amplification of highly conserved regions of the viral genome), ranging from 0 to 100%. Advances in meta-genomics have permitted detection of HPV viral signatures that were previously cost-prohibitive, and there appears to be a potential role for both low-risk and high-risk in the cause of the disease. Activating EGFR mutations have also been identified to be correlated with malignant transformation, which may be exclusive of HPV infection. Furthermore, more comprehensive approaches in detecting genomic markers have been reported, with HOX-related genes and epithelial-mesenchymal-transition-related gene sets appear to be differentially upregulated.

SUMMARY

Sinonasal inverted papilloma is a diverse disease that is predominantly benign, but it harbours the potential for malignant degeneration in the SCCa with cause yet to be elucidated. Current evidence supports a potential role for high-risk HPV in a subset of SCCa, with the role of low-risk HPV yet to be defined. Historic studies of individual and small groups of molecular markers have not consistently adequate characterize signalling pathways underpinning the oncogenesis, and comprehensive genomic studies are needed to better understand the disease.

The prognostic significance of human papilloma virus in sinonasal squamous cell carcinoma

BACKGROUND

Human papilloma virus (HPV) has been implicated in the pathology of oropharyngeal head and neck cancers, but its role in sinonasal squamous cell carcinoma (SNSCC) has not been well established.

METHODS

Thirty-two patients with SNSCC diagnosed between 2011 and 2018 were identified and stratified by HPV status and viral serotype, as determined by PCR. Endpoints including recurrence, metastases and survival were analyzed using the Kaplan-Meier method.

RESULTS

Seventeen (53%) patients were HPV-positive and 15 (47%) were HPV-negative. The median follow-up time of living patients was 30.7 months (range 4-123 months). Survival did not differ by HPV status, but HPV+ tumors were more likely to locally recur and metastasize. When stratifying by treatment type, the lowest rate of recurrence occurred in patients receiving surgery and chemoradiation.

CONCLUSION

A significant proportion of sinonasal tumors appear to be associated with HPV. Testing for HPV might be justified in all cases of sinonasal cancers. Further investigation is warranted to better understand the role of HPV in SNSCC.

Middle Ear and Temporal Bone Nonkeratinizing Squamous Cell Carcinomas With DEK-AFF2 Fusion: An Emerging Entity

Primary squamous cell carcinomas (SCCs) of the middle ear and temporal bone are rare and usually keratinizing by morphology. Nonkeratinizing, basaloid SCCs arising in this area are exceedingly rare, and, due to the anatomic proximity to the skull base, nasopharynx, and nasal sinuses, the differential diagnosis is broad. Most tumors with squamous differentiation arising in these subsites are either viral-induced (human papillomavirus/Epstein-Barr virus) or rarely may have specific molecular alterations (BRD4-NUT, EWSR1-FLI translocations). Occasional tumors are negative for these findings, and their pathogenesis is unknown. A recently discovered DEK-AFF2 fusion was clinically detected in a series of 2 cases known to the authors. This fusion has been previously reported in the literature in a patient with a base of skull tumor who was an exceptional responder to programmed cell death protein 1 inhibitor therapy. We examine here the histomorphologic and molecular findings of 2 additional cases of an emerging entity. Two male patients were identified. Each had a primary middle ear/temporal bone mass with locally advanced disease. The histology was reviewed, and immunohistochemistry was performed. RNA-based next-generation sequencing was performed for clinical detection of diagnostic or actionable fusions. Both patients had basaloid/nonkeratinizing tumors on biopsy. They were positive for markers of squamous differentiation (HMWK, CK5, and p40). By RNA sequencing, they demonstrated the presence of a DEK-AFF2 fusion and were negative for EWSR1 and NUT translocations. The DEK-AFF2 fusion may define a novel diagnostic category of middle ear and temporal bone nonkeratinizing/basaloid SCCs. This fusion also may represent a potential avenue for immunotherapy in these patients. Further studies are needed to fully explore whether this fusion defines a location-specific clinicopathologic entity.

A clinical analysis of sinonasal squamous cell carcinoma: a comparison of de novo squamous cell carcinoma and squamous cell carcinoma arising from inverted papilloma

Background: Sinonasal squamous cell carcinoma (SCC) is a rare tumor arising either de novo or in association with inverted papillomas (IPs).Objectives: The aim of this study was to investigate and compare the oncological features and prognosis of patients with sinonasal SCCs based on their etiology.Material and methods: The medical records of 117 patients who had been diagnosed with de novo SCC or those arising from IP (IP-SCC) were retrospectively reviewed. In situ hybridization analyses to detect HPV 16/18DNA and p16 immunohistochemistry were also performed in 10 cases with IP-SCC.Results: The three-year disease-specific survival (DSS) rate was higher in cases with T1, 2 and 3 than in cases with T4 in both tumor groups. T4 cases with de novo SCC had a better DSS than those with IP-SCCs. HPV16/18 was not detected in any of the 10 IP-SCCs.Conclusions and significance: T4 cases with de novo SCC tended to have a better DSS than those with IP-SCC. Since some T4 patients with IP-SCC were found to have a highly aggressive disease, careful treatment planning should be performed. High-risk HPV may not play a vital role in the carcinomatous transformation of most IP-SCC cases.

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

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

SUMMARY

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

Sinonasal Squamous Cell Carcinoma Presentation and Outcome: A National Perspective

BACKGROUND

examine presentation and outcomes of sinonasal squamous cell carcinoma (SCC).

METHODS

A retrospective study utilizing the National Cancer Database, 2004 to 2015. The study population included adult patients diagnosed with primary sinonasal SCC.

RESULTS

A total of 537 patients were included. The mean age of the study population was 62.6 ± 12.7 years. The median follow-up time was 35.6 months (interquartile range: 8.6-55.9). The histological variants identified are: (i) 66.7% keratinizing SCC, (ii) 21.6% non-keratinizing SCC, (iii) 8.0% papillary SCC, and (iv) 3.7% spindle cell carcinoma. Stage at presentation was: (i) 33.3% T1-2, N0, (ii) 31.8% T3-4a, N0, (iii) 13.8% T1-4a, N+, (iv) 17.0% T4b,N0-3, (v) 4.1% M1. Human papilloma virus (HPV) status was available for 96 patients and tested positive in 24 (25.0%) patients. By histological variants, 5-year survival was lowest for spindle cell carcinoma (40.0%), and highest for papillary SCC (70.1%). HPV negative tumors had a 5-year survival of 26.4%, while HPV positive tumors had a 5-year survival of 57.1% (P = <.001). Of the 255 patients with T1-4a, N0-3, M0 who had surgery of the primary site, 31 (12.2%) patients underwent endoscopic approach. The risk of positive postsurgical margins was not significantly different comparing endoscopic to open approach (23.8% vs 24.1%, P >.99).

CONCLUSIONS

Sinonasal SCC could present at advanced stages in two-thirds of the population and exhibit a variety of histological subtypes. Like other sites of head and neck, HPV positive tumors are associated with a favorable prognosis. Endoscopic approach is comparable to open approach in terms of post-surgical margins.

Prevalence of human papillomavirus in sinonasal squamous cell carcinoma with and without association of inverted papilloma in Eastern China

Background

Information on HPV-associated sinonasal squamous cell carcinoma (SNSCC) is very limited in China. The aim of this study was to determine the prevalence of HPV in a large cohort of SNSCC patients in China.

Methods

Clinical records and formalin-fixed and paraffin-embedded tumor specimens from 30 SNSCC patients with associated inverted papilloma (IP-SNSCC) and 84 de novo SNSCC (DN-SNSCC) patients were retrieved between 2010 and 2017. HPV status was determined for each specimen using a combination of p16 immunohistochemistry and GP5+/6+ PCR.

Results

Immunohistochemistry for p16 was positive in two IP-SNSCC patients (2/30, 6.7%) and in 16 DN-SNSCC patients (16/84, 19.0%). HPV DNA was detected in six IP-SNSCC patients (6/30, 20%) and in three DN-SNSCC patients (3/84, 3.8%). Expression of p16 was not correlated with the presence of HPV DNA (p = 0.150). Among 18 p16-positive SNSCC patients, only three were HPV DNA-positive. Furthermore, only three of nine HPV DNA-positive tumors exhibited high p16 expression. In IP-SNSCC patients, only one of six HPV DNA-positive tumors exhibited high p16 expression. In DN-SNSCC patients, two of three HPV DNA-positive tumors exhibited high p16 expression. The positive rates for both HPV DNA and p16 in IP-SNSCC patients and DN-SNSCC patients were 3.3 and 2.4%, respectively.

Conclusions

Immunostaining for p16 is not a reliable surrogate marker of HPV status in SNSCC. The presence of HPV is rarely detected in DN-SNSCC patients in Eastern China. IP-SNSCC patients frequently lack of p16 overexpression despite the presence of high-risk HPV DNA.

Clinical management of emerging sinonasal malignancies

Several emerging sinonasal malignancies have recently been described in the pathology literature. Although not all distinctly classified by the World Health Organization, these rare tumors present a management challenge to surgeons and oncologists. While prior studies have summarized histologic details, a clinically focused review is currently lacking in the literature. This review describes the presentation, histopathology, imaging, treatment, and prognosis of newly described or recently evolving sinonasal malignancies while highlighting the distinguishing features of these entities. It includes teratocarcinosarcoma, human papillomavirus-related multiphenotypic carcinoma, biphenotypic sinonasal sarcoma, sinonasal renal cell-like adenocarcinoma, NUT-midline carcinoma, squamous cell carcinoma associated with inverted papilloma, sinonasal undifferentiated carcinoma, and INI-1-deficient sinonasal carcinoma. By describing the diagnosis, treatment, and prognosis of these recently defined entities, this clinical review aims to help guide oncologists in the clinical management of these patients.

Sinonasal cancer: an overview of the emerging subtypes

BACKGROUND

Advances in immunohistochemistry have spearheaded major developments in our understanding and classification of sinonasal tumours. In the last decade, several new distinct histopathological entities of sinonasal cancer have been characterised.

OBJECTIVES

This review aims to provide a clinical update of the major emerging subtypes for the ENT surgeon and an overview of the management strategies available for this heterogeneous group of pathologies.

CONCLUSION

Although rare, knowledge of sinonasal neoplasm subtypes has implications for prognosis, treatment strategies and the development of novel therapeutic targets.

P16 and human papillomavirus in sinonasal squamous cell carcinoma

Human papillomavirus (HPV) in oropharyngeal squamous cell carcinoma (SCC) is a well-known cause and prognostic indicator, and the utility of p16 as a surrogate marker for HPV status has been established. P16 and its relationship with HPV have not been defined in sinonasal malignancy nor has a link with outcomes been established. Patients with sinonasal SCC from 2011 to 2017 were identified from our pathology database. P16 immunohistochemistry and HPV RNA in situ hybridization were performed on tissue specimens. Forty-seven patients were included. Disease-free survival for p16+ patients was significantly higher than p16- patients (P = .043). Fewer HPV+ patients died (P = .052) or experienced recurrence (P = .0437). Odds ratio between p16 and HPV status was 14.19 (95% CI: 1.72, 442.03). Our findings demonstrate improved survival in both the p16+ and HPV+ groups and a positive association between p16 and HPV. There may be similar potential for modifying classification for HPV+ sinonasal SCC.

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.

Human Papillomavirus Related Multiphenotypic Sinonasal Carcinoma: Report of a Case with Early and Progressive Metastatic Disease

Introduction  Human papillomavirus (HPV) related multiphenotypic sinonasal carcinoma (HMSC) is a newly described entity. The prognosis of this neoplasm is not well understood, but cases often demonstrate high-grade features and paradoxically indolent behavior.

Case Report  We present the case of a 65-year-old man referred with unilateral nasal congestion and epistaxis. Nasal endoscopy and imaging revealed an expansile mass filling the left nasal cavity. The patient underwent endoscopic-assisted medial maxillectomy, with complete resection and negative margins. Pathology revealed a basaloid tumor consisting of solid nests with multiple foci of cribriform architecture, with positivity for high-risk HPV, thus supporting the diagnosis of HMSC. Postoperatively, the patient received 66.6-Gy adjuvant three-dimensional proton therapy. Twenty-three months after surgical resection, he developed enlarging pulmonary nodules with biopsy features consistent with the primary sinonasal tumor. He was treated with three cycles of chemotherapy and eight cycles of immunotherapy, progressing on both therapies. He remains on palliative chemotherapy.

Conclusion  Here, we present a case of HMSC with early and progressive distant metastasis. We aim to add to an understanding of the behavior of this entity. Although this neoplasm may typically be indolent, further classification of high-risk features is necessary to identify rare aggressive cases.

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

Context.—

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

Objective.—

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

Data Sources.—

Review of pertinent literature regarding sinonasal papillomas and sinonasal carcinomas.

Conclusions.—

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

HPV-Related Multiphenotypic Sinonasal Carcinoma: A Unique Case

Human papillomavirus (HPV)-related multiphenotypic sinonasal carcinoma (HMSC), originally known as HPV-related carcinoma with adenoid cystic carcinoma-like features, is a recently described neoplasm that presents only in the sinonasal tract, displays features of both a surface-derived carcinoma and a salivary gland carcinoma, and is associated with high-risk HPV, specifically HPV type 33. Majority of the cases display high-grade histologic features, but HMSC paradoxically behaves in a relatively indolent fashion. Distinguishing HMSC from other histologic mimickers is essential as the management and prognosis are significantly different. In this article, we present a unique case of HMSC and review the literature.

Association of OX40 gene polymorphisms (rs17568G/A and rs229811A/C) with head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC) is the sixth leading incident cancer worldwide. In this study, we aimed to investigate the possible association of OX40 gene polymorphisms, rs17568G/A and rs229811A/C, with susceptibility to HNSCC and its clinicopathological features. Two hundred and two HNSCC patients and 200 healthy age-sex matched individuals were enrolled. rs17568G/A and rs229811A/C polymorphisms in OX40 gene were genotyped using RFLP-PCR method. We observed more than 2 times increased risk for squamous cell carcinoma development in nose and paranasal sinuses among individuals who inherited GG genotype at rs17568 region (OR 2.29; CI 1.01-5.20; P = 0.035). Considering rs2298211 SNP, AA genotype was also observed with higher frequency, in comparison with other two genotypes (AC or CC), among patients with HNSCC originated from these regions (P = 0.003). Besides, we observed that patients with C allele at this locus (AC and CC genotypes) have tumors with significantly higher histological grade (P = 0.042). Our findings suggest the possible association of rs17568 GG genotype, as well as rs2298211 AA genotype with susceptibility to develop squamous cell carcinoma in the nose and sinonasal cavities.

Headache Caused by Sinus Disease

Headaches and sinus disease are common reasons to seek medical care, with marked worldwide prevalence and large socioeconomic burdens. Headaches caused by sinus diseases are rare; many "rhinogenic headaches" are actually migraines. The similar symptoms may result from autonomic dysfunction and trigeminovascular pathways. Using the mnemonic ACHE, this article presents key Anatomy, Clinical cases, How to image, Essential clinical and radiographic features that help the radiologist, otolaryngologist, and neurologist evaluate sinus disease and headaches.

Whole-Exome Sequencing of Sinonasal Small Cell Carcinoma Arising within a Papillary Schneiderian Carcinoma In Situ

OBJECTIVE

The pathogenetic underpinnings of extrapulmonary small cell carcinomas (EPSCCs) of the head and neck are poorly understood. We sought to describe the clinical case and whole-exome DNA sequencing data of a patient with sinonasal Schneiderian carcinoma in situ whose tumor progressed to small cell carcinoma (SCC).

STUDY DESIGN

Case report and whole-exome sequencing of tumor DNA.

SETTING

Academic medical center.

SUBJECTS AND METHODS

A 52-year-old man with sinonasal Schneiderian carcinoma in situ whose tumor progressed to small cell carcinoma. We performed whole-exome genetic sequencing and copy-number variation (CNV) analysis of tumor and normal DNA extracted from flash-frozen, paraffin-embedded (FFPE) samples.

RESULTS

A total of 93 high-confidence, nonsynonymous somatic mutation events were identified in sinonasal SCC, including loss-of-function mutations in TP53, MAML3, a transcriptional coactivator of the Notch pathway, and GAS6, an activating ligand of the TAM family of tyrosine kinase receptors. Focal amplifications of chromosomal regions 6p25-11.1, containing SOX4 and VEGFA, and 14q32.1-32.3, containing AKT1 and the Notch inhibitory ligand DLK1, were also seen. Further CNV analysis revealed deletions in the critical cell cycle regulators CDKN2A, RB1, RBL1, and RBL2 and the chromatin modifier EP300.

CONCLUSIONS

Small cell carcinoma may rarely arise from sinonasal Schneiderian carcinoma in situ and exhibits similar genomic aberrations (eg, SOX amplification, Notch pathway inactivation) to pulmonary small cell carcinoma.

Combination of serum squamous cell carcinoma antigens 1 and 2 as potential diagnostic marker for sinonasal squamous cell carcinoma and inverted papilloma

BACKGROUND

Differentiating inverted papilloma from squamous cell carcinoma (SCC) is sometimes difficult. We evaluated the clinical usefulness of serum SCCA1 and SCCA2 in the management of patients with inverted papilloma or SCC.

METHODS

Serum and tissue samples for the analysis of SCCA1, SCCA2, and SCC antigen were taken from 18 patients with sinonasal inverted papilloma and 23 cases with sinonasal SCC. The SCCA1, SCCA2, and SCC antigen levels were determined.

RESULTS

The serum SCCA1 concentration was significantly higher in the inverted papilloma group than in the SCC group, whereas the serum SCCA2 level was significantly higher in the SCC group than in the inverted papilloma group.

CONCLUSION

Patients with sinonasal inverted papilloma predominantly express SCCA1 protein, whereas those with SCC predominantly express SCCA2. This suggests that combined measurements of both serum SCCA1 and SCCA2 concentrations can be very useful for distinguishing sinonasal inverted papilloma from SCC.

Strong SOX10 expression in human papillomavirus-related multiphenotypic sinonasal carcinoma: report of 6 new cases validated by high-risk human papillomavirus mRNA in situ hybridization test

Human papillomavirus (HPV)-related multiphenotypic sinonasal carcinoma (HMSC) is associated with high-risk HPV (HR-HPV) infection. Using HR-HPV messenger RNA (mRNA) in situ hybridization (ISH), we reported 6 new HMSC cases and compared their histopathology with that of sinonasal adenoid cystic carcinoma. Using p16 immunohistochemistry (IHC) and HR-HPV ISH, we retrospectively identified 6 HMSC cases. All HMSC cases were positive for HR-HPV mRNA ISH and p16 IHC. Two HMSC cases had overlying atypical squamous epithelium, and 1 had invasive squamous cell carcinoma (SCC). All HMSC cases were SOX10 positive, whereas the overlying atypical squamous epithelium and the SCC were SOX10 negative. One atypical HMSC-like case was also identified, which was positive for HR-HPV mRNA ISH, HR-HPV DNA ISH, and SOX10 IHC, but negative for p16 IHC. This study showed that HR-HPV mRNA ISH was a useful tool to diagnose HMSC and had stronger signals compared with HR-HPV DNA ISH. HR-HPV E6/E7 mRNA could be identified in the overlying atypical squamous epithelium and the invasive SCC. A combination of p16 and SOX10 IHC will be a useful screening panel for HMSC followed by confirmatory HR-HPV mRNA ISH test.

Endoscopic endonasal approaches for the management of cranial base malignancies: histologically guided treatment and clinical outcomes

Malignancies of the skull base represent a highly diverse and challenging set of pathologies which exhibit a wide array of oncologic behavior. In recent decades, a number of important advances in treatment technique have evolved to improve oncologic outcomes and reduce morbidity in the treatment of these aggressive cancers. Intensity modulated radiation therapy has become the gold standard in radiotherapy owing to its precision planning and reduced morbidity. However heavy ion particle radiation (proton therapy, carbon ion, etc.) are recently emerging with promising results at the skull base related to the reduced exit dose to adjacent structures. Novel systemic therapeutics such as targeted and immunotherapies may dramatically alter the treatment paradigm for many of these pathologies. Nevertheless, most skull base malignancies remain surgical diseases. The evolution of the expanded endonasal approach for a minimally invasive surgical resection has proven validity in treating many of these pathologies when properly selected, and have largely supplanted open approaches owing to the reduced morbidity profile. In spite of these important advances, the most critical aspect in comprehensive treatment is a detailed understanding of the oncologic behavior and outcomes data for each of the specific histopathologies encountered at the skull base. The nuances in management strategy, histologic profile, and surveillance planning can be stratified through the development of a comprehensive, multidisciplinary skull base team to maximize therapeutic effect and minimize morbidity for each patient. This review aims to summarize the key body of data and approaches for each of the histologies frequently encountered in the skull base, while highlighting the value and technique of endonasal approaches.

Immunohistochemistry, carcinomas of unknown primary, and incidence rates

Pathologists use immunohistochemistry is their day-to-day practices to assist in distinguishing site of origin of metastatic carcinomas. Here, the work-up is discussed neuroendocrine carcinomas, squamous cell carcinomas and adenocarcinomas with particular attention to tumor incident rates and predictive values of the best-performing immunohistochemical markers.

The Impact of Histologic Phenotype in the Treatment of Sinonasal Cancer

The management of sinonasal cancer is a challenge due to its low occurrence and anatomical and significant diversity of histological types. The therapeutic modality used should be tailored individually according to the histology, tumour stage, molecular profile and previous treatments. The clinical management of sinonasal cancer has improved greatly owing to developments in endoscopic surgery and precision radiotherapy. Complete surgical resection is the mainstay of sinonasal malignancies' management but multimodality therapy is associated with improved outcomes in certain histologies. The recognition of various histological types with biological behaviours more suitable for non-surgical modalities has allowed treatment protocols to become more tailored to the disease. In this review we aim to describe and to summarise the current data guiding the management of sinonasal cancer with emphasis on phenotypic variation.

Evaluation of Patients with Sinonasal and Ventral Skull Base Malignancies

A wide variety of tumors present in the sinonasal and ventral skull base. Patients often have nonspecific symptoms initially and present with advanced tumors, affecting the orbit and other adjacent structures. Evaluation of these malignancies with modern imaging techniques can define tumor invasion, but biopsy is often required to establish a diagnosis because most have a nonspecific appearance. A thorough understanding of the anatomy is the key to treatment planning, and a multidisciplinary approach determines the optimal strategy.

Prevalence of Human Papilloma Virus in Sinonasal Papilloma in Southern Iranian Population

STATEMENT OF THE PROBLEM

Sinonasal papilloma (SNP) is a rare benign lesion characterized by high recurrence rate and malignant transformation.

PURPOSE

This study aimed to investigate the prevalence of human papilloma virus (HPV) infection in these lesions in South of Iran.

MATERIALS AND METHOD

In this cross sectional retrospective study, a total of 41 patients, 38 SNP and 3 SNP/Squamous cell carcinoma cases, from 2007 to 2014 were studied. Human papilloma virus (HPV) DNA detection was performed by nested PCR method and positive cases were analyzed for high risk HPV-16 and HPV-18.

RESULTS

HPV was detected in 31.7%; HPV- 16 in 4.9% and HPV 18 was not detected at all. Dysplastic epithelium was detected in 53% that was not associated with HPV. Three cases were accompanied with malignant transformation that HPV genome was detected in only one case and none of them were positive for HPV16 /18 genomic DNA.

CONCLUSION

Current research suggests that HPV may be involved in the development of SNP. But the high risk HPV is not important in malignant transformation. More studies are needed to elucidate the possible etiologic mechanism between HPV, inverted papilloma, and squamous cell carcinoma.

Sinonasal adenoid cystic carcinoma: Treatment outcomes and association with human papillomavirus

BACKGROUND

The purpose of this study was to review long-term outcomes of sinonasal adenoid cystic carcinoma (ACC) and to clarify its association with human papillomavirus (HPV).

METHODS

The medical records of 23 patients with sinonasal ACC treated with primary surgical resection between 1998 and 2013 were reviewed. Tissue specimens were available for 17 patients. The p16 testing was performed using immunohistochemistry (IHC), and HPV infection was determined using quantitative polymerase chain reaction (PCR) with primers targeting the E6/E7 region.

RESULTS

Two of the 17 samples showed strong and diffuse p16 staining, whereas the remaining 15 cases showed p16-positivity isolated to the luminal cells. Only one of the p16-positive cases was positive for HPV. The 5-year local failure, disease-free survival (DFS), and overall survival (OS) were 51%, 52%, and 62%, respectively.

CONCLUSION

Local failures are common with advanced sinonasal ACC, and the association of HPV with true sinonasal ACC is low.

AHNS series: Do you know your guidelines? Management of head and neck cancer in the era of human papillomavirus: Educating our patients on human papillomavirus

Human papillomavirus (HPV) has changed the face of head and neck cancer over the past 2 decades. No longer is this solely a disease of older patients with a history of heavy tobacco and alcohol use. Patients with HPV-related head and neck cancers tend to be younger, healthier, and have an improved prognosis, compared with those with HPV-negative tumors. As more patients are diagnosed with HPV-related head and neck cancer, physicians have important topics to consider. These include prevalence, transmission, and natural history of HPV, the role of screening, vaccines, and HPV testing in head and neck cancer. This article continues a series developed by the American Head and Neck Society's Education Committee entitled "Do you know your guidelines?" and is intended to provide guidance for navigating common questions and concerns patients may have about HPV infection and HPV-related head and neck cancer. © 2017 Wiley Periodicals, Inc. Head Neck 39: 833-839, 2017.

Human Papillomavirus-Associated Neoplasms of the Head and Neck

Human papillomavirus (HPV) is an essential causal factor in a subset of head and neck neoplasms, most notably oropharyngeal squamous cell carcinoma, for which HPV infection has important diagnostic, prognostic, and therapeutic implications. This article summarizes the current understanding of HPV-associated neoplasms of the head and neck, including the recently described carcinoma with adenoid cystic-like features. Salient clinical, gross, and microscopic features are discussed, and the utility of specific ancillary studies is highlighted.

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.

Virus-associated neoplasms of the nasopharynx and sinonasal tract: diagnostic problems

A significant fraction of nasopharyngeal and sinonasal tumors are associated with Epstein-Barr virus (EBV) or human papillomavirus (HPV). Nasopharyngeal carcinoma (NPC) and extranodal NK/T-cell lymphoma harbor EBV in practically all cases, although a small proportion of cases of the former harbor HPV. Sinonasal inverted papillomas harbor HPV in about 25% of cases. Sinonasal squamous cell carcinomas harbor transcriptionally active HPV in about 20% of cases, and limited data suggest that this subset has a better prognosis than the HPV-negative subset. This review addresses the diagnostic issues of the EBV-associated tumors. Difficulties in diagnosis of NPC may be encountered when there are prominent crush artifacts, many admixed lymphoid cells masking the neoplastic cells, or numerous interspersed granulomas, whereas benign cellular components (epithelial crypts and germinal centers) and reactive lymphoid hyperplasia can potentially be mistaken for NPC. Immunostaining for pan-cytokeratin and/or in situ hybridization for EBER can help in confirming or refuting a diagnosis of NPC. The main diagnostic problem of extranodal NK/T-cell lymphoma is recognition of the neoplastic nature of those examples predominated by small cells or showing a mixture of cells. The identification of a destructive infiltrate (dense expansile infiltrate; angiocentric growth) and definite cytologic atypia (clear cells; many medium-sized cells) would favor a diagnosis of lymphoma, which can be supported by immunohistochemistry (most commonly CD3+, CD5-, CD56+) and in situ hybridization for EBER. In conclusion, among nasopharyngeal and sinonasal neoplasms, demonstration of EBV may aid in diagnosis, particularly NPC and extranodal NK/T-cell lymphoma. Demonstration of HPV does not have a role yet in diagnosis, although this may change in the future.

Sinonasal Small Round Blue Cell Tumors: An Immunohistochemical Approach

Although clinical history and morphologic appearance should be the initial considerations when evaluating small round blue cell tumors of the sinonasal tract, the final diagnosis often hinges on immunohistochemical findings. Unfortunately, interpretation of stains in these tumors is fraught with numerous pitfalls and limitations. This article presents an approach to sinonasal small round blue cell tumors based on four common immunohistochemical patterns: cytokeratin positivity, squamous marker positivity, neuroendocrine marker positivity, and cytokeratin negativity.

Evaluation for High-risk HPV in Squamous Cell Carcinomas and Precursor Lesions Arising in the Conjunctiva and Lacrimal Sac

High-risk human papilloma virus (HR-HPV) is a well-established causative agent of oropharyngeal squamous cell carcinoma (SCC). In addition, HR-HPV has occasionally been reported to be present in dysplastic and malignant lesions of the conjunctiva and lacrimal sac, although its overall incidence and etiological role in periocular SCC are controversial. Sequential surgical samples of 52 combined cases of invasive SCC (I-SCC) and SCC in situ (SCCIS) from 2 periocular sites (conjunctiva and lacrimal sac) diagnosed over a 14-year period (2000 to 2014) were selected for evaluation, and relevant patient characteristics were documented. p16 immunohistochemistry was performed as a screening test. All p16-positive cases were further evaluated for HR-HPV using DNA in situ hybridization (DNA ISH), and a subset was also analyzed by polymerase chain reaction (PCR). Of 43 ocular surface squamous neoplasias (OSSNs), 30% (n=13; 8 SCCIS and 5 I-SCC cases) were positive for HR-HPV. HPV-positive OSSNs occurred in 8 men and 5 women with a mean age of 60 years (range, 39 to 94 y). HPV type-16 was detected in all conjunctival cases evaluated by PCR. All 5 conjunctival I-SCCs were nonkeratinizing (n=4) or partially keratinizing (n=1) and managed by simple excision. In contrast, HPV-negative conjunctival I-SCCs were predominantly keratinizing (11 keratinizing and 2 nonkeratinizing). Of 9 lacrimal sac I-SCCs (LSSCCs), 66.7% (n=6) were positive for HR-HPV by p16 and DNA ISH; HPV subtypes were HPV-16 (n=5) and HPV-58 (n=1). In addition, 2 p16-positive cases with negative DNA ISH results were HR-HPV positive (HPV-16 and HPV-33) when evaluated by PCR, suggesting that the rate of HR-HPV positivity among the LSSCCs may be as high as 89% (n=8). The combined group of HR-HPV-positive LSSCCs was seen in 4 men and 4 women with a mean age of 60 years (range, 34 to 71 y). Seven of the 8 HPV-positive LSSCCs (87.5%) had a nonkeratinizing or partially keratinizing histomorphology, whereas 1 case (12.5%) was predominantly keratinizing. The presence of HR-HPV in 30% of OSSNs and at least 66.7% of LSSCCs suggests the possibility of an etiologic role for HR-HPV at these sites.

Large Cell Neuroendocrine Carcinoma of the Head and Neck: A Clinicopathologic Series of 10 Cases With an Emphasis on HPV Status

Large cell neuroendocrine carcinoma (LCNEC) is a high-grade neuroendocrine neoplasm first described in the lung and subsequently well documented in many other anatomic sites. It has only recently been recognized that LCNEC can also occasionally arise in the head and neck. The role of human papillomavirus (HPV), which is associated with some small cell carcinomas of the head and neck, has not been investigated for LCNEC. We sought to further characterize the histologic, immunophenotypic, and clinical features of LCNEC and also investigate the role of HPV in this newly described group of tumors. The surgical pathology archives of 2 large academic institutions were searched for cases of LCNEC arising in the head and neck. p16 immunohistochemistry and HPV in situ hybridization were performed, and clinical information was obtained from electronic medical records. Ten cases of head and neck LCNEC were identified. The tumors arose in 6 men and 4 women ranging in age from 14 to 70 years (median, 63.5 y). The primary tumor sites were the oropharynx (n=4), the sinonasal tract (n=3), and the larynx (n=3). The LCNECs consisted of nests and trabeculae of medium-large cells with abundant cytoplasm, coarse chromatin, and prominent nucleoli with very high mitotic rates. The tumor nests were often associated with necrosis, peripheral palisading, and rosette formations. The LCNECs were positive for pan-cytokeratin and at least 1 neuroendocrine marker (most often synaptophysin) and were largely negative for p63 (focal staining in 2/10) and CK5/6 (staining in 1/10). The LCNECs demonstrated aggressive clinical behavior: 8 of 10 presented with advanced disease, 5 of 10 died, with 4 more living but with persistent tumor. Three of 10 LCNECs were HPV-related (HPV-LCNEC); they arose in the oropharynx (n=2) and sinonasal tract (n=1). The HPV-LCNECs did not differ from the HPV-negative tumors in histologic appearance or behavior: 2 patients with HPV-LCNEC have died because of their disease and 1 remains alive but with widespread metastases. LCNEC is a rare but distinct form of head and neck carcinoma that exhibits aggressive clinical behavior. A subset of oropharyngeal and sinonasal LCNEC is HPV related, but the presence of HPV may not impart a more favorable prognosis. Because of its aggressive behavior, LCNEC should be distinguished from moderately differentiated neuroendocrine carcinoma and squamous cell carcinoma. The morphology of LCNEC overlaps considerably with the nonkeratinizing appearance of HPV-related squamous cell carcinoma, and as a result a high index of suspicion is needed to identify LCNEC. Immunohistochemical studies for synaptophysin and p63 are helpful tools for making this distinction.

Clinical management of squamous cell carcinoma associated with sinonasal inverted papilloma

OBJECTIVE

The aim of this study was to investigate the clinical features and prognosis of patients with squamous cell carcinoma (SCC) associated with sinonasal inverted papilloma (IP).

METHODS

The medical records of 95 patients who were diagnosed with IP or SCC associated with IP were retrospectively reviewed. Out of 95 patients, 15 were diagnosed with SCC associated with IP. The clinical characteristics, treatment modalities, and survival outcomes of the patients were analyzed.

RESULTS

The incidence of SCC associated with IP was 15.8%. Although differential diagnosis between IP and SCC associated with IP is difficult, epistaxis may be the specific symptom in SCC associated with IP cases. The 3-year disease-specific survival rate was higher in cases with T1, 2 and 3 than in cases with T4. There was no significant difference in survival rate between maxillary sinus and other primary sites. On the other hand, there was a significant difference in survival rate between the microscopic SCC with IP cases and the other cases. In addition, the patients with <70 years old better than those with >70 years old with a 3-year disease free survival of 80% versus 0%.

CONCLUSIONS

Some T4 patients were found to have a highly aggressive disease. Therefore, complete surgical resection followed by chemo-radiation therapy is the recommended treatment for patients with T4 disease to control of the primary tumor site.

Newly Described Tumor Entities in Sinonasal Tract Pathology

Surgical pathology of the sinonasal tract (nasal cavity and paranasal sinuses) is extremely challenging due in part to the tremendous diversity of tumor types that may arise in this region. Compounding the difficulty, a number of new sinonasal tumor entities have been recently described, and pathologists may not yet be familiar with these neoplasms. This manuscript will review the clinicopathologic features of some of the newly described sinonasal tumor types: NUT midline carcinoma, HPV-related carcinoma with adenoid cystic-like features, SMARCB1 (INI-1) deficient sinonasal carcinoma, biphenotypic sinonasal sarcoma, and renal cell-like adenocarcinoma.

Sinonasal Squamous Cell Carcinoma: A Review with Emphasis on Emerging Histologic Subtypes and the Role of Human Papillomavirus

The sinonasal tract is one of the least frequent sites for squamous cell carcinoma in the head and neck. However, it is still a complex tumor type for pathologists because there are numerous histologic variants with unusual morphologic features, several non-squamous carcinomas in the differential diagnosis that can have similar morphology and even squamous differentiation, and because of the increasing recognition of human papillomavirus (HPV) in a subset of the tumors. In addition, the unique and complex anatomy of the sinonasal tract can make proper staging and management of patients' tumors quite challenging. This article reviews sinonasal tract squamous cell carcinoma in depth and provides the latest data on Schneiderian papillomas and HPV in their pathogenesis.

Recently described neoplasms of the sinonasal tract

Surgical pathology of the sinonasal region (i.e., nasal cavity and the paranasal sinuses) is notoriously difficult, due in part to the remarkable diversity of neoplasms that may be encountered in this area. In addition, a number of neoplasms have been only recently described in the sinonasal tract, further compounding the difficulty for pathologists who are not yet familiar with them. This manuscript will review the clinicopathologic features of some of the recently described sinonasal tumor types: NUT midline carcinoma, HPV-related carcinoma with adenoid cystic-like features, SMARCB1 (INI-1) deficient sinonasal carcinoma, biphenotypic sinonasal sarcoma, and adamantinoma-like Ewing family tumor.