Sinonasal undifferentiated carcinoma, nasopharyngeal-type undifferentiated carcinoma, and keratinizing and nonkeratinizing squamous cell carcinoma express different cytokeratin patterns

Assessment of targeted therapy opportunities in sinonasal cancers using patient-derived functional tumor models

Malignant tumors derived from the epithelium lining the nasal cavity region are termed sinonasal cancers, a highly heterogeneous group of rare tumors accounting for 3 - 5 % of all head and neck cancers. Progress with next-generation molecular profiling has improved our understanding of the complexity of sinonasal cancers and resulted in the identification of an increasing number of distinct tumor entities. Despite these significant developments, the treatment of sinonasal cancers has hardly evolved since the 1980s, and an advanced sinonasal cancer presents a poor prognosis as targeted therapies are usually not available. To gain insights into potential targeted therapeutic opportunities, we performed a multiomics profiling of patient-derived functional tumor models to identify molecular characteristics associated with pharmacological responses in the different subtypes of sinonasal cancer.

METHODS

Patient-derived ex vivo tumor models representing four distinct sinonasal cancer subtypes: sinonasal intestinal-type adenocarcinoma, sinonasal neuroendocrine carcinoma, sinonasal undifferentiated carcinoma and SMARCB1 deficient sinonasal carcinoma were included in the analyses. Results of functional drug screens of 160 anti-cancer therapies were integrated with gene panel sequencing and histological analyses of the tumor tissues and the ex vivo cell cultures to establish associations between drug sensitivity and molecular characteristics including driver mutations.

RESULTS

The different sinonasal cancer subtypes display considerable differential drug sensitivity. Underlying the drug sensitivity profiles, each subtype was associated with unique molecular features. The therapeutic vulnerabilities correlating with specific genomic background were extended and validated with in silico analyses of cancer cell lines representing different human cancers and with reported case studies of sinonasal cancers treated with targeted therapies.

CONCLUSION

The results demonstrate the importance of understanding the differential biology and the molecular features associated with the different subtypes of sinonasal cancers. Patient-derived ex vivo tumor models can be a powerful tool for investigating these rare cancers and prioritizing targeted therapeutic strategies for future clinical development and personalized medicine.

The increased expression of cytokeratin 13 leads to an increase in radiosensitivity of nasopharyngeal carcinoma HNE-3 cells by upregulating ERRFI1

The main factors contributing to the unfavorable outcome in the clinical treatment of patients with nasopharyngeal carcinoma (NPC) patients are radiation resistance and recurrence. This study aimed to investigate the sensitivity and molecular foundation of cytokeratin 13 (CK13) in the radiotherapy of NPC. To achieve this, a human NPC cell line overexpressing CK13, HNE-3-CK13, was constructed. The effects of CK13 overexpression on cell viability and apoptosis under radiotherapy conditions were evaluated using the CCK-8 assay, immunofluorescence, and western blotting (WB). Next-generation sequencing was performed to identify the downstream genes and signaling pathways of CK13 that mediate radiotherapy response. The potential role of the candidate gene ERRFI1 in CK13-induced enhancement of radiosensitivity was investigated through rescue experiments using clone formation and WB. The effects of ERRFI1 on cell viability, cell apoptosis, cell cycle, and the related key genes were further evaluated using CCK-8, immunofluorescence, flow cytometry, quantitative polymerase chain reaction and WB. The results showed that CK13 overexpression in HNE-3 significantly inhibited cell survival under radiotherapy and promoted apoptosis marker γH2AX expression, leading to a significant increase of ERRFI1. Knockdown of ERRFI1 rescued the decreased cell viability and proliferation and the increased cell apoptosis that were caused by CK13 overexpression-mediated radiotherapy sensitization of NPC cells. In this process, EGFR, AKT, and GSK-3β were found involved. In the end, ERRFI1 was proven to inhibit expression levels of CDK1, CDK2, cyclin B1, and cyclin D1, resulting an increased G2/M cell ratio. Overexpression of CK13 enhances the radiosensitivity of NPC cells, which is characterized by decreased cell viability and proliferation and increased apoptosis. This regulation may affect the survival of HNE-3 cells by increasing the expression of ERRFI1 and activating the EGFR/Akt/GSK-3β signaling pathway, providing new potential therapeutic targets for the treatment of NPC.

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.

The contemporary management of cancers of the sinonasal tract in adults

Sinonasal malignancies make up <5% of all head and neck neoplasms, with an incidence of 0.5-1.0 per 100,000. The outcome of these rare malignancies has been poor, whereas significant progress has been made in the management of other cancers. The objective of the current review was to describe the incidence, causes, presentation, diagnosis, treatment, and recent developments of malignancies of the sinonasal tract. The diagnoses covered in this review included sinonasal undifferentiated carcinoma, sinonasal adenocarcinoma, sinonasal squamous cell carcinoma, and esthesioneuroblastoma, which are exclusive to the sinonasal tract. In addition, the authors covered malignances that are likely to be encountered in the sinonasal tract-primary mucosal melanoma, NUT (nuclear protein of the testis) carcinoma, and extranodal natural killer cell/T-cell lymphoma. For the purpose of keeping this review as concise and focused as possible, sarcomas and malignancies that can be classified as salivary gland neoplasms were excluded.

Cancers associated with human gammaherpesviruses

Epstein-Barr virus (EBV; human herpesvirus 4; HHV-4) and Kaposi sarcoma-associated herpesvirus (KSHV; human herpesvirus 8; HHV-8) are human gammaherpesviruses that have oncogenic properties. EBV is a lymphocryptovirus, whereas HHV-8/KSHV is a rhadinovirus. As lymphotropic viruses, EBV and KSHV are associated with several lymphoproliferative diseases or plasmacytic/plasmablastic neoplasms. Interestingly, these viruses can also infect epithelial cells causing carcinomas and, in the case of KSHV, endothelial cells, causing sarcoma. EBV is associated with Burkitt lymphoma, classic Hodgkin lymphoma, nasopharyngeal carcinoma, plasmablastic lymphoma, lymphomatoid granulomatosis, leiomyosarcoma, and subsets of diffuse large B-cell lymphoma, post-transplant lymphoproliferative disorder, and gastric carcinoma. KSHV is implicated in Kaposi sarcoma, primary effusion lymphoma, multicentric Castleman disease, and KSHV-positive diffuse large B-cell lymphoma. Pathogenesis by these two herpesviruses is intrinsically linked to viral proteins expressed during the lytic and latent lifecycles. This comprehensive review intends to provide an overview of the EBV and KSHV viral cycles, viral proteins that contribute to oncogenesis, and the current understanding of the pathogenesis and clinicopathology of their related neoplastic entities.

Cytokeratin 13 promotes radiotherapy sensitivity of nasopharyngeal carcinoma by downregulating the MEK/ERK pathway

BACKGROUND

Radiation therapy is the first treatment choice for nasopharyngeal carcinoma (NPC), while radiation resistance and recurrence have become the primary factors and are associated with poor prognosis in the clinical treatment of NPC patients. The purpose of the present study was to explore the sensitivity and molecular basis of cytokeratin 13 (CK13) that regulates NPC radiotherapy.

METHODS

HNE-3 or C666-1 cell line was used for overexpression and knockdown tests. Under radiotherapy conditions, CCK-8 assay, clone formation assay, and flow cytometry analyzed the effects of CK13 overexpression on cell proliferation, apoptosis, and cell cycle, respectively. In addition, Western blotting detected CK13-mediated downregulation of cell cycle-related genes. The mouse subcutaneous tumor-bearing experiment identified the effects of CK13 overexpression on the treatment of NPC in vivo. Further, Western blotting, CCK-8 assay, and flow cytometry investigated whether the CK13-mediated cell apoptosis involves the MEK/ERK signaling pathway.

RESULTS

Overexpression of CK13 significantly inhibited the survival of HNE-3 cells under radiotherapy in vitro and in vivo, and there was a substantial decrease in cyclin-dependent kinase 4 and 6 (CDK4/6) levels promoting the cell percentage number in the G2/M phase and, subsequently, the ratio of the apoptotic cells. In contrast, the knockdown of CK13 showed the opposite partial regulatory effect. Interestingly, CK13 overexpression also showed a reduction in the survival of C666-1 cells and an increased ratio of the apoptotic cells under radiotherapy treatment. Furthermore, higher levels of CK13 downregulated the MEK/ERK signaling pathway, resulting in decreased HNE-3 cell proliferation and increased apoptosis. However, ERK activators were able to rescue the process partially.

CONCLUSIONS

Together, these results showed that CK13 promoted the radiosensitivity of NPC cells by downregulating the MEK/ERK signaling pathway. Thus, targeting CK13 provided insights into the treatment of NPC radiotherapy.

Development of head and neck pathology in Europe

This review gives a brief history of the development of head and neck pathology in Europe from a humble beginning in the 1930s to the explosive activities the last 15 years. During the decades before the introduction of immunohistochemistry in the 1980s, head and neck pathology grew as a subspeciality in many European countries. In the late 1940s, the Institute of Laryngology and Otology with its own pathology laboratory was founded in London, and in 1964 the World Health Organization (WHO) International Reference Centre for the Histological Classification of Salivary Tumours was established at the Bland-Sutton Institute of Pathology, also in London. International collaboration, and very much so in Europe, led to the publication of the first WHO Classification of Salivary Gland Tumours in 1972. In the 1960s, a salivary gland register was organised in Hamburg and in Cologne the microlaryngoscopy was invented enabling microscopic endoscopic examination and rather shortly afterwards a carbon dioxide laser attached to the microscope became established and laryngeal lesions could be treated by laser vaporisation. During the last three decades, the use of immunohistochemistry supplemented with cytogenetic and refined molecular techniques has greatly facilitated the pathological diagnostics of head and neck lesions and has had a huge impact on research. Collaboration between different European centres has drastically increased partly due to establishment of scientific societies such as the Head and Neck Working Group (HNWG) within the European Society of Pathology and the International Head and Neck Scientific Group (IHNSG). A very large number of European pathologists have contributed to the 2nd, 3rd and 4th WHO books, and are involved in the upcoming 5th edition. Accredited educational meetings and courses are nowadays regularly arranged in Europe. Numerous textbooks on head and neck pathology have been written and edited by European pathologists. The increased collaboration has created larger series of tumours for research and new entities, mainly defined by their genetic abnormalities, are continuously emerging from Europe, particularly regarding salivary gland neoplasms and "undifferentiated" sinonasal tumours. These findings have led to a better and more precise classification and open the possibilities for new treatment strategies.

Undifferentiated and dedifferentiated head and neck carcinomas

Undifferentiated carcinomas arising at salivary gland and head and neck mucosal sites may originate either de novo or through a process of dedifferentiation of a differentiated carcinoma. While in the latter group the diagnosis is largely dependent on the identification of the differentiated component or recognition of a specific genotype, the classification of undifferentiated carcinomas that lack a differentiated component is mainly based on the identification of specific genetic drivers, like for example the NUTM1 fusions in NUT carcinoma. A further category is represented by virus associated carcinomas (mainly HPV and EBV), that frequently displays an undifferentiated morphology. Overall, these tumors often represent a diagnostic challenge, especially in small biopsies. This review summarizes and discuss the diagnostic approach to the main head and neck carcinoma types that frequently or occasionally display an undifferentiated appearance, with a focus on salivary gland, oropharyngeal, nasopharyngeal and sinonasal subsites.

A Unique Case of Primary EBV-Positive, HPV-Negative Nasopharyngeal Carcinoma Located in the Tonsil

Nasopharyngeal carcinomas (NPC) are non-keratinizing squamous cell carcinomas of the nasopharynx associated with Epstein-Barr virus (EBV). When occurring outside of the nasopharynx, they are referred to as lymphoepithelioma-like carcinomas (LELCs) and present the same morphology as NPC. LELC have been described in other head and neck regions such as the salivary glands and the soft palate. LELC can also occur in the oropharynx, are associated with human papillomavirus (HPV) and are typically negative for EBV. We herein present a unique case of a 78-year-old Chinese male with EBV-positive, HPV-negative NPC of the left tonsil. His presenting symptom was a left-sided lymph node. There was no evidence of nasopharyngeal lesion seen on physical examination, PET and MRI. The patient was treated with curative-intent external beam radiotherapy which delivered 70 Gy (Gy) to the gross tumour and lymph nodes, and 56 Gy electively to the ipsilateral neck using a volumetric modulated arc therapy technique. This is the first case of primary tonsil EBV-positive NPC described in the literature.

A Rare Case of Sinonasal Lymphoepithelial Carcinoma Presented With Clinically Stage IV Disease

Sinonasal lymphoepithelial carcinoma (SLEC) is an extremely rare malignancy. We present a case of SLEC in a 77-year-old man who presented with nasal congestion and persistent sinusitis. Imaging revealed a large right nasal mass involving right paranasal sinuses along with bulky bilateral cervical lymphadenopathy. In addition, there was a fluorodeoxyglucose avid L1 vertebral lesion. Biopsy of nasal mass and cervical lymph nodes showed syncytial growth of tumor cells in a lymphoplasmacytic background. Immunohistochemical stains showed positivity for pankeratin, CK5/6, epithelial membrane antigen, p40 (focal), and p63 (focal). An Epstein-Barr virus-encoded RNA by in situ hybridization was strong and diffusely positive. Based on these pathologic findings and considering the location of tumor, diagnosis of SLEC was rendered. L1 vertebral body lesion was clinical and radiologically considered to be a metastasis. Correlation with radiology to determine the exact location of tumor is extremely important for correct diagnosis due to its histopathologic similarities with relatively more common undifferentiated type of nasopharyngeal carcinoma. No standard treatment protocol has been established for this tumor yet. To our knowledge, this is first ever report of SLEC presented with clinical stage IV disease.

Clinicopathologic profile of sinonasal neoplasia in Kano, Northwestern Nigeria: A 10-year single-institution experience

Background

Sinonasal neoplasia comprises approximately 3% of all head-and-neck tumors. However, the incidence of these tumors may be greater in some parts of the world including Asia and Africa.

Aim and Objective

The study aimed to review the clinical and histopathological pattern of sinonasal neoplasms in Kano, Nigeria.

Materials and Methods

The records of patients managed for sinonasal neoplasia at the Department of Otorhinolaryngology, Aminu Kano Teaching Hospital, Kano, Nigeria, over a period of 10 years were reviewed. Information obtained from the case files included demographic characteristics, tumor characteristics, and clinical information. The data obtained were analyzed using SPSS version 23.

Results

A total of 245 patients were reviewed with sinonasal neoplasms. Among these, 168 (68.57%) were males, with a sex ratio (M:F) of 2.18:1. The mean age was 40.2 ± 18.9 years. Malignant sinonasal neoplasm constituted 55.92%% of the sinonasal neoplasia, with peak age at the fifth decade. Squamous cell carcinoma was the most common histological subtypes seen in 50.36% of the patients. Inverted papilloma was the most common benign sinonasal neoplasia (42.59%). The most common symptom presented by the patients was nasal obstruction (77.55%), mostly presented within 6 months of onset of symptoms (63.67%), and farmers were the predominant (27.76%). The most common treatment modality was surgical extirpation (54%), and most of the patients presented with Stage IV disease (88%). The site of tumor was found to statistically correlate with the type of tumor among the patients (P ≤ 0.0001), whereas the type of tumor and site of tumor correlated significantly with the duration of symptoms before the presentation.

Conclusion

Malignant sinonasal disease is the predominant sinonasal neoplasm in this environment, and most of the patients presented with advanced disease.

ICAR: endoscopic skull-base surgery

BACKGROUND

Endoscopic skull-base surgery (ESBS) is employed in the management of diverse skull-base pathologies. Paralleling the increased utilization of ESBS, the literature in this field has expanded rapidly. However, the rarity of these diseases, the inherent challenges of surgical studies, and the continued learning curve in ESBS have resulted in significant variability in the quality of the literature. To consolidate and critically appraise the available literature, experts in skull-base surgery have produced the International Consensus Statement on Endoscopic Skull-Base Surgery (ICAR:ESBS).

METHODS

Using previously described methodology, topics spanning the breadth of ESBS were identified and assigned a literature review, evidence-based review or evidence-based review with recommendations format. Subsequently, each topic was written and then reviewed by skull-base surgeons in both neurosurgery and otolaryngology. Following this iterative review process, the ICAR:ESBS document was synthesized and reviewed by all authors for consensus.

RESULTS

The ICAR:ESBS document addresses the role of ESBS in primary cerebrospinal fluid (CSF) rhinorrhea, intradural tumors, benign skull-base and orbital pathology, sinonasal malignancies, and clival lesions. Additionally, specific challenges in ESBS including endoscopic reconstruction and complication management were evaluated.

CONCLUSION

A critical review of the literature in ESBS demonstrates at least the equivalency of ESBS with alternative approaches in pathologies such as CSF rhinorrhea and pituitary adenoma as well as improved reconstructive techniques in reducing CSF leaks. Evidence-based recommendations are limited in other pathologies and these significant knowledge gaps call upon the skull-base community to embrace these opportunities and collaboratively address these shortcomings.

Sinonasal Undifferentiated Carcinoma (SNUC): From an Entity to Morphologic Pattern and Back Again-A Historical Perspective

Since the first description of sinonasal undifferentiated carcinoma (SNUC) as a distinctive highly aggressive sinonasal neoplasm with probable origin from the sinonasal mucosa (Schneiderian epithelium), SNUC has been the subject of ongoing study and controversy. In particular, the SNUC category gradually became a "wastebasket" for any undifferentiated or unclassifiable sinonasal malignancy of definite or probable epithelial origin. However, with the availability of more specific and sensitive immunohistochemical antibodies and increasing implementation of novel genetic tools, the historical SNUC category became the subject of progressive subdivision leading to recognition of specific genetically defined, reproducible subtypes. These recently recognized entities are characterized by distinctive genetic aberrations including NUTM1-rearranged carcinoma (NUT carcinoma) and carcinomas associated with inactivation of different members of the SWI/SNF chromatin-remodeling gene complex such as SMARCB1-deficient and less frequently SMARCA4-deficient carcinoma. The ring became almost closed, with recent studies highlighting frequent oncogenic IDH2 mutations in the vast majority of histologically defined SNUCs, with a frequency of 82%. A review of these cases suggests the possibility that "true SNUC" probably represents a distinctive neoplastic disease entity, morphologically, phenotypically, and genetically. This review addresses this topic from a historical perspective, with a focus on recently recognized genetically defined subsets within the SNUC spectrum.

Sinonasal Undifferentiated Carcinoma

PURPOSE OF REVIEW

To provide a comprehensive review of the literature highlighting the recent advances in the diagnosis and management of sinonasal undifferentiated carcinoma (SNUC) RECENT FINDINGS: SNUC usually presents at advanced stage and the prognosis is usually poor with high rates of locoregional recurrence and tendency to metastasize. Special attention should be made in differentiating SNUC from other sinonasal malignancies in order to guide the appropriate treatment accordingly. Multimodality treatment is usually recommended for treating SNUC. The use of neoadjuvant chemotherapy may be associated with improved outcome and can be used to guide the subsequent treatment selection. Despite the recent advances in chemotherapeutic agents, radiation techniques, and surgical approaches, the prognosis and survival outcomes of SNUC remain poor. The addition of induction chemotherapy to the treatment approach followed by definitive local therapy needs to be further studied as it might improve the outcome.

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.

Aggressive esthesioneuroblastoma with divergent differentiation: A taxonomic dilemma

The authors describe an esthesioneuroblastoma (olfactory neuroblastoma) that occurred within the nasal cavity and brain in a 31-year-old man. Following excision, the tumor recurred in the left orbit and in mediastinal lymph nodes. Treatment included orbital excision and systemic chemotherapy. Histopathology showed a high-grade neuroepithelial tumor with positive immunohistochemical markers for neuroendocrine and epithelial components, an unusual combination raising issues concerning taxonomy.

Intestinal-type sinonasal adenocarcinomas: The road to molecular diagnosis and personalized treatment

BACKGROUND

Sinonasal intestinal-type adenocarcinomas (ITACs) are epithelial tumors of the nasal cavity and the paranasal sinuses, often related to professional exposure to organic dust, mainly wood or leather. It is a rare cancer. If resectable, surgery is the treatment of choice. Postoperative radiotherapy is often indicated to increase local control. Systemic treatment (chemotherapy, targeted agents, or immunotherapy) of irresectable ITACs and/or metastasized disease is less standardized.

METHODS

Articles on ITAC histopathology, molecular profile, and current treatment options of this specific tumor were identified and reviewed, using the electronic databases Pubmed, Medline, Cochrane, and Web of Science.

RESULTS

This article reviews what is currently known on the histopathology, tumorigenesis, molecular characteristics, and standardized treatment options of ITAC.

CONCLUSION

More translational research is needed to identify druggable targets that may lead to a personalized treatment plan in order to improve long-term outcome in patients with locally advanced and/or metastasized ITAC. © 2016 Wiley Periodicals, Inc. Head Neck 38: First-1570, 2016.

An Update on Sinonasal Round Cell Undifferentiated Tumors

The sinonasal cavities host a wide variety of undifferentiated malignancies with round cell morphology, including neoplasms of epithelial, mesenchymal, neuroectodermal, and hematolymphoid lineage. The differential diagnosis may be difficult, especially in small biopsy material, due to overlapping morphology, but their correct classification is clinically relevant. The aim of this review is to provide practical guidelines for the differential diagnosis of these malignancies, with emphasis on recently described entities and special reference to the role of ancillary techniques.

Nasal Cavity and Paranasal Sinuses

The nasal cavity and paranasal sinuses occupy the top of the upper respiratory tract and form pneumatic spaces connected with the atmosphere. They are located immediately beneath the base of the cranium, where crucial vital structures are harbored. From this region, very much exposed to airborne agents, arise some of the more complex and rare benign and malignant lesions seen in humans, whose difficulties in interpretation make this remarkable territory one of the most challenging in the practice of surgical pathology.

Contents of this chapter cover inflammations and infections, polyps and pseudotumors, fungal and midfacial destructive granulomatous lesions, as well as benign, borderline, and malignant neoplasms. Among the neoplasms, emphasis is made on those entities characteristic or even unique for the sinonasal region, such as Schneiderian papillomas, glomangiopericytoma, intestinal- and non-intestinal-type adenocarcinomas, olfactory neuroblastoma, nasal-type NK-/T-cell lymphoma, and teratocarcinosarcoma. Moreover, recently recognized entities involving this territory, i.e., HPV-related non-keratinizing carcinoma, NUT carcinoma, and SMARCB1-deficient basaloid carcinoma, are also discussed in the light of their specific molecular findings. Furthermore, the text is accompanied by numerous classical and recent references, several tables, and 100 illustrations.

Immunohistochemical expression of keratins 6, 7, 8, 14, 16, 18, 19, and MNF-116 pancytokeratin in primary and metastatic melanoma of the head and neck

OBJECTIVE

To investigate the immunohistochemical expression (IHCE) of selected keratins in primary cutaneous and mucosal melanoma (pM), and metastatic melanoma (metsM) of the head and neck and to compare their expression to a group of undifferentiated/poorly differentiated tumors of the same anatomic region.

STUDY DESIGN

IHCE of K6, K7, K8, K14, K16, K18, and K19 were studied in 29 melanomas and 70 cases of non-melanoma tumors of the same anatomic region (neuroendocrine carcinoma, neuroblastoma, olfactory neuroblastoma, sinonasal undifferentiated carcinoma, undifferentiated nasopharyngeal carcinoma, anaplastic large cell lymphoma, poorly differentiated squamous cell carcinoma (PDSCC), and Ewing sarcoma). MNF-116 pancytokeratin was investigated in melanoma.

RESULTS

All studied keratins, except K6, were expressed in melanoma. IHCE of MNF-116, K8, and K18 was higher in metsM compared with pM. K14 and K16 expression was highest in PDSCC.

CONCLUSIONS

metsM expresses keratins more than pM, specifically K8, K18, and MNF-116. Keratin positivity in an undifferentiated or poorly differentiated neoplasm does not necessarily exclude the diagnosis of melanoma.

Sinonasal small round blue cell tumors: An approach to diagnosis

The differential diagnosis for small round cell tumors in the sinonasal tract is diverse and as the body of literature documenting not only uncommon presentations but also availability of ancillary studies grows, so does the need for a reminder to take a conservative and thorough approach before rendering a diagnosis. Small tissue samples are particularly problematic, with limitations that include volume of tumor cells available for studies, lack of architectural context and a non-specific gross description. Incorporation of patient history and presentation, radiologic findings, clinical impression and concurrent studies often guide the course of studies performed by the pathologist. If these are non-specific, the pathologist may need to perform ancillary studies, including a broad panel of immunohistochemical stains and molecular studies. If tissue is limited, a precise classification may not be achievable. Although the expectation to render a definitive diagnosis is high, the pathologist should never feel compelled to go further with a diagnosis than the tissue itself supports.

Diagnostic value of next-generation sequencing in an unusual sphenoid tumor

Extraordinary advancements in sequencing technology have made what was once a decade-long multi-institutional endeavor into a methodology with the potential for practical use in a clinical setting. We therefore set out to examine the clinical value of next-generation sequencing by enrolling patients with incurable or ambiguous tumors into the Personalized OncoGenomics initiative at the British Columbia Cancer Agency whereby whole genome and transcriptome analyses of tumor/normal tissue pairs are completed with the ultimate goal of directing therapeutics. First, we established that the sequencing, analysis, and communication with oncologists could be completed in less than 5 weeks. Second, we found that cancer diagnostics is an area that can greatly benefit from the comprehensiveness of a whole genome analysis. Here, we present a scenario in which a metastasized sphenoid mass, which was initially thought of as an undifferentiated squamous cell carcinoma, was rediagnosed as an SMARCB1-negative rhabdoid tumor based on the newly acquired finding of homozygous SMARCB1 deletion. The new diagnosis led to a change in chemotherapy and a complete nodal response in the patient. This study also provides additional insight into the mutational landscape of an adult SMARCB1-negative tumor that has not been explored at a whole genome and transcriptome level.

Treatment outcomes and prognostic factors, including human papillomavirus, for sinonasal undifferentiated carcinoma: a retrospective review

BACKGROUND

Sinonasal undifferentiated carcinoma (SNUC) is a high-grade, aggressive neoplasm. Low incidence and poor outcomes make identification of prognostic factors and treatment standardization difficult. Similarly, little is known regarding the association of human papillomavirus (HPV) with SNUC.

METHODS

A retrospective review was conducted. Extracted information included treatment received, tumor recurrence, patient survival, p16 expression, and HPV status. The Kaplan-Meier method was used to estimate overall survival (OS) and disease-free survival (DFS). Survival trends were compared using the log-rank test.

RESULTS

Nineteen patients received multimodality treatment for SNUC. Five-year OS and DFS rates were 45.2% and 50.7%, respectively, with no significant difference between treatment types. Tumors from 11 patients were p16-positive and 9 of these were also HPV-positive. Kaplan-Meier analysis demonstrated improved survival.

CONCLUSION

Our series demonstrates a higher prevalence of HPV in SNUC than previously reported. HPV-positive SNUCs may benefit from improved survival and should be investigated further in future studies.

Radiotherapy for sinonasal undifferentiated carcinoma

PURPOSE

To evaluate the long-term effectiveness of radiotherapy (RT) in the treatment of sinonasal undifferentiated carcinoma (SNUC).

MATERIALS AND METHODS

The medical records of 23 patients treated with definitive or postoperative RT between 1992 and 2010 at the University of Florida were retrospectively reviewed. Fifteen patients (65%) received primary surgery and postoperative RT. Radiation doses ranged from 59.0 to 74.8 Gy (median, 70.2 Gy). The median follow-up time for all patients was 3.0 years (range, 0.9-19.9), and for living patients was 7.7 years (range, 2.5-19.9).

RESULTS

The actuarial 5-year survival outcomes were as follows: progression-free survival, 42%; cause-specific survival, 43%; and overall survival, 32%. Actuarial 5-year disease control rates were as follows: local control (infield or marginal), 74%; local-regional control (excluding leptomeningeal spread), 58%, regional control 78%, freedom from leptomeningeal recurrence, 72%, and distant metastasis-free survival, 73%. Five of the 8 (62.5%) patients treated with definitive RT died with disease, and 6 of the 15 patients (40%) treated with primary surgery and postoperative RT died with disease. Three patients (13%) experienced severe complications including unilateral eye removal, osteoradionecrosis of the maxilla requiring hyperbaric oxygen and surgery, and brain necrosis. One patient died due to an infected bone graft and brain abscess.

CONCLUSIONS

A multimodal approach is best when treating SNUC patients. The prognosis for patients treated with definitive RT ± chemotherapy is less promising than for those who receive surgery and postoperative RT ± chemotherapy. Severe complications occur in about 17% of patients due to the high dose of RT alone or combined with surgery required for acceptable disease control.

Sinonasal undifferentiated carcinoma: morphological heterogeneity, diagnosis, management and biological markers

Sinonasal undifferentiated carcinoma is a highly aggressive lesion arising in the superior nasal cavity and paranasal sinuses. Differential diagnosis is wide because a range of similar lesions can present at this site. There is increasing evidence that sinonasal undifferentiated carcinoma is a surface (Schneiderian) epithelial-derived malignancy, with or without concurrent neuroendocrine differentiation. Prognosis is poor; recurrence with metastasis to lymph nodes and distant sites is frequent. A combination of radical surgery, chemotherapy and radiotherapy appears to provide the best chance of survival.

Role of p40 and cytokeratin 5/6 in the differential diagnosis of sinonasal undifferentiated carcinoma

Sinonasal undifferentiated carcinoma (SNUC) is an epithelial neoplasm of sinonasal region which does not exhibit a squamous or glandular differentiation. The challenge in diagnosis of this entity is the rarity of the disease, the varying morphology of the tumor which leads to gamut of differential diagnosis and the paucity of consistent immunohistochemical markers except pancytokeratin. Forty-one cases of sinonasal epithelial neoplasm consisting of 11 cases of SNUC and 10 cases each of high-grade (grade 3 and 4) esthesioneuroblastoma, undifferentiated nasopharyngeal carcinoma, and poorly differentiated squamous cell carcinoma of the sinonasal region were analyzed for morphology and immunoexpression of CK5/6 and p40. It was found that SNUC did not exhibit immunohistochemical expression of p40 and CK 5/6, suggesting that these could be useful negative immune markers for diagnosis of SNUC.

Sinonasal undifferentiated carcinoma presenting as recurrent fronto-ethmoidal pyomucocele

We describe a case of a 53-year-old man presented to our ENT OPD with chief complaints of recurrent right supraorbital swelling for last 6 months, which was associated with bilateral periorbital edema. Contrast-enhanced computerized tomographic scan showed a large frontoethmoidal mucocele with expansion of the bone but there was no erosion. Endoscopic marsupialization along with external frontoethmoidectomy was done to treat the patient and the collected pus, fluid and necrotic tissue was sent for HPE. Biopsy came out to be sinonasal carcinoma, which is a rare occurrence in frontal sinus. Moreover, sinonasal carcinoma presenting as recurrent frontoethmoidal mucocele has not been reported till date in the literature to the best of our knowledge. This case is being reported to make aware among all ENT surgeons and to be cautious about such presentation.

The small round blue cell tumors of the sinonasal area: histological and immunohistochemical findings

Background

Primary Small round blue cell tumors (SRBCT) in sinonasal comprise histogenetically diverse entities with overlapping morphologic features. Because of the limited initial biopsy tissue materials, differential diagnostic difficulties may arise, and as they have different management, exact diagnosis and classification are very important.

Objectives

In this study, we analyzed the immunohistochemical expression of a panel of markers in the classification and diagnosis of sinonasal SRBCTs.

Material and Methods

This cross sectional study was performed on 36 paraffin embedded tissue samples. Histologic and immunohistochemical slides from 36 patients with SRBCT were analyzed retrospectively. The patients were admitted in Khalili hospital, Shiraz from 1383 to 1388.

Results

There were 13 women and 23 men with the mean age of 53 ±12.1. There were 9 malignant melanoma, seven poorly differentiated SCC; six lymphoma (DLBL); 4 SCNEC; three SNUC; two ON; two Ewing/PNET; two embryonal rhabdomyosarcoma, and one plasmacytoma. Pan-cytokeratin was strongly expressed poorly differentiated SCC and all cases of SNUC. Coexpression of desmin and nuclear myoD1 was only detected in rhabdomyosarcoma. HMB45 was only expressed in sinonasal melanoma. CD99 expression was identified only in Ewing/PNET. FLI-1 was detected in 50% of PNET. P63 was expressed in poorly differentiated SCC (2/7) and SNUC (1/3).

Conclusions

The results of our study indicate that the integration of histopathologic findings with application of limited but highly specific markers led to the separation of carcinomas, lymphoma and melanomas from other small cell tumors. Using a panel of keratin, LCA, desmin, and HMB45 is the most practical and economic approach to accurately classify these tumors.

Lymphoepithelial carcinoma in the maxillary sinus: a case report

Introduction

Lymphoepithelial carcinoma of the maxillary sinus is a very rare malignancy and it can be difficult to make a pre-operative diagnosis.

Case presentation

A 72-year-old Caucasian woman presented to our facility with an isolated right-side epistaxis that had been present for three months, with the results of a computed tomography scan showing a soft tissue mass in the right maxillary sinus with an impacted tooth. The results of a transnasal endoscopic biopsy were compatible with a lymphoepithelial carcinoma, following which our patient underwent a radical excision of the mass. The final histology results revealed lymphoepithelial carcinoma of the maxillary sinus with negative assays for Epstein-Barr virus. Our patient was given post-operative external radiotherapy and has remained disease-free at three-year follow-up.

Conclusions

This report details the diagnosis and management of a case of lymphoepithelial carcinoma of the maxillary sinus, which is a very rare malignant tumor with very little mention in the literature. Only a strong suspicion with systematic use of various patho-immunological tests helps to arrive at a definitive diagnosis by excluding other better-known tumors.

[Retrobulbar optic neuropathy secondary to an undifferentiated carcinoma of the sphenoid sinus]

Undifferentiated carcinoma of the paranasal sinuses is a rare malignant tumor, characterized by rapid growth, local/regional invasion, metastatic potential and poor prognosis despite aggressive treatment. Clinically, this tumor may manifest as episodes of epistaxis, headache or ophthalmic signs, particularly oculomotor nerve palsies, optic atrophy or even proptosis in the case of orbital extension. We report the case of a patient admitted with a left retrobulbar optic neuropathy, which led to a diagnosis of undifferentiated carcinoma of the sphenoid sinus.

Sino nasal undifferentiated carcinoma: A rare entity

Malignant neoplasms of the paranasal sinuses and nasal cavity are rare, comprising only 3% of all head and neck malignancies. This includes both primary sinonasal neoplasms and metastatic disease. We present the case of a patient with a maxillary soft tissue swelling, which proved to be a rare malignant tumor of maxillary sinus origin, a sinonasal undifferentiated carcinoma

Establishment and characterization of novel cell lines from sinonasal undifferentiated carcinoma

PURPOSE

Sinonasal undifferentiated carcinoma (SNUC) is a rare and aggressive cancer. Despite the use of multimodality treatment, the overall prognosis remains poor. To better understand the biologic features of SNUC and help develop new therapies for the disease, we established SNUC cell lines and characterized their biologic behaviors.

EXPERIMENTAL DESIGN

Cell lines were established from a patient with a T4N0M0 SNUC of the right maxillary sinus who was treated with surgical resection at our center. Tumor colonies were harvested and were sequentially replated onto larger plates. Two populations were developed and labeled MDA8788-6 and MDA8788-7. These cell lines were characterized with molecular, biomarker, functional, and histologic analyses.

RESULTS

Short tandem repeat genotyping revealed that the cell line is isogenic to the parental tumor, and cytogenetic analysis identified 12 chromosomal translocations. The SNUC cell lines do not form colonies in soft agar but are tumorigenic and nonmetastatic in an orthotopic mouse model of sinonasal cancer. Western blot analysis revealed that both MDA8788 cell lines express epithelial markers but do not express mesenchymal markers or the endocrine marker synaptophysin.

CONCLUSIONS

This is the first report of the establishment of stable human-derived SNUC cell lines. The lines were highly tumorigenic and maintain the histologic and molecular features of the original tumor. These cell lines should serve as useful tools for the future study of SNUC biology and the development and testing of novel therapies for this deadly disease.

Sinonasal undifferentiated carcinoma with intracranial extension

AIM

To report our experience in the management of sinonasal undifferentiated carcinoma (SNUC) over a period of 15 years.

STUDY DESIGN

A retrospective case review of 13 patients with SNUC treated at the University of California, Davis, Medical Center (UCDMC) Center for Skull Base Surgery, over the past 15 years.

RESULTS

Most tumors arose in the ethmoid sinuses. All but 1 patient had a combined intracranial-extracranial resection through the anterior fossa-transcranial route and postoperative irradiation. The 13th patient had a transfacial subcranial approach. There are 6 who have survived free of disease at 14 years' to 8 months' follow-up. The average follow-up was 6 years, 3 months. One patient died of a pulmonary embolism in the first postoperative week, a second died of a bowel infarction 3 months postoperatively. Three patients died of their disease at 20, 18, and 8 months postoperatively: 1 with local recurrence and distant metastasis and the other 2 with local control but distant disease. The 6 survivors are at 8, 20, 28, 62, 84, and 105 months.

CONCLUSION

SNUC is a rare malignancy of the paranasal sinuses with a poor prognosis. Radical surgery and adjunctive therapy can achieve good survival in a significant proportion of patients who would hitherto have seemed incurable.

Meta-analysis of treatment outcomes for sinonasal undifferentiated carcinoma

OBJECTIVES

This study reviews the published outcomes regarding sinonasal undifferentiated carcinoma (SNUC) since the initial description in 1986. This article attempts to (1) understand and better describe the benefit and survival advantages associated with using radiation, chemotherapy, and surgical treatment and (2) support the recommendations of a treatment regimen with current available data in the literature.

DATA SOURCES

Published English-language literature.

REVIEW METHODS

A PubMed search for articles related to SNUC, along with the bibliographies of those articles to avoid missing articles. All articles were examined for an independent patient data meta-analysis. Thirty studies with 167 cases from 1986 to October 2009 were identified. Demographics, disease extent, treatment, follow-up, and survival were analyzed. Patient cohorts mirroring Kadish staging were created. Kaplan-Meier curves were constructed.

RESULTS

Follow-up range was 1 to 195 months (mean 23.4 months, median 15 months). At last follow-up, 26.3% of patients were alive with no evidence of disease, 21.0% were alive with disease, and 52.7% were dead of disease. The use of surgery was found to be the best single modality, but chemotherapy and radiation were important as adjuncts in extensive and aggressive disease. The presence of neck metastases was a poor prognostic sign.

CONCLUSION

This study, containing the largest pool of SNUC patients, confirms a poor overall prognosis. The data suggest that the optimal treatment should include surgery, with radiation and/or chemotherapy as adjunct treatments. Neck disease in advanced local disease is a poor prognostic sign and merits aggressive treatment with multimodality therapy.

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.

Expression of p16 in sinonasal undifferentiated carcinoma (SNUC) without associated human papillomavirus (HPV)

Sinonasal undifferentiated carcinoma (SNUC) is an uncommon and highly aggressive neoplasm of the paranasal sinuses and nasal cavity. Its undifferentiated histologic appearance often requires immunohistochemical studies to distinguish it from other high-grade neoplasms. Due to the rarity of SNUC, its immunohistochemical staining profile has been incompletely characterized, and little work has been done on its expression of the markers for human papillomavirus (HPV). Our objective is to expand our knowledge of its immunophenotype and its association with HPV in order to define markers with mechanistic potential in the disease process, or of possible therapeutic importance. A total of five patients (one woman and four men) with SNUC, ranging in age from 26 to 75 years (mean 56.8 years) were compared to five patients (five men) with poorly differentiated squamous cell carcinoma (PDSCC), ranging in age from 53 to 75 years (mean 62.2 years). PDSCC was chosen as a control, given its well-reported immunohistochemical profile and negativity for HPV markers. The immunohistochemical panel included: CK7, CK19, EMA, NSE, chromogranin, p53, CK5/6, p63, CK14, S100, HMB-45, desmin, muscle specific actin, and CD45. Additionally, tests for p16, EBV, and HPV (subtypes 6, 11 16, 18) were performed. The diagnosis of SNUC was confirmed in all cases by histology and immunohistochemical stains. An interesting finding of strong diffuse positivity for p16 was noted in all SNUC cases, compared to only two of five PDSCC that were positive for p16. HPV DNA was not detected in any SNUC cases or any cases of PDSCC. All SNUC cases demonstrated over expression of p16 in the absence of HPV DNA expression. This may represent residual epithelial p16 staining, which is normally present in the sinonasal tract. Due to the rarity of SNUC, more cases will need to be evaluated to confirm the absence of HPV DNA.

Current diagnostic strategies for undifferentiated tumours of the nasal cavities and paranasal sinuses

Several malignant tumours occurring in the sinonasal tract may present with an undifferentiated morphology. Overall, these lesions pose significant diagnostic difficulties for the surgical pathologist, especially in limited biopsy material, but their correct classification is becoming increasingly important for an appropriate treatment strategy. This review deals with the criteria for differential diagnosis of these neoplasms, with emphasis on recent advances in immunohistochemistry and molecular biology, as well as with previous progress in electron microscopy. Through careful microscopic examination of haematoxylin and eosin-stained sections, in the light of clinical information and imaging data, a list of differential diagnoses can be made and an appropriate panel of antibodies can be chosen to further categorize the tumour. An initial panel including cytokeratins, synaptophysin, S100 protein, desmin and CD45 may allow the classification of most lesions or may help to narrow the list of differential diagnoses. Further refinement can be obtained through second-line markers, including in-situ hybridization for Epstein-Barr virus, other neuroendocrine markers, melanocytic markers, myogenin, CD99, other lymphocyte markers, and CD138 and light chains. Finally, molecular analysis can further assist in the recognition of specific entities such as nuclear protein in testis midline carcinoma, Ewing's sarcoma/peripheral neuroectodermal tumour, alveolar rhadbomyosarcoma, and poorly differentiated synovial sarcoma.

Pure sarcomatoid carcinoma of maxillary sinus and nasal cavity simulating malignant fibrous histiocytoma

Although a few cases of sinonasal carcinoma with focal sarcomatous differentiation have been reported, pure sarcomatoid carcinoma has not been reported in the English literature. Imaging studies and gross inspection in a 60-year-old man with left-sided face pain revealed a mass in the left maxillary sinus and nasal cavity. A large incisional biopsy specimen from the nasal cavity revealed proliferation of malignant spindle and round cells with a malignant fibrous histiocytoma (MFH) pattern. Tumor giant cells were scattered, and there were areas of a vague storiform pattern. Mitotic figures were numerous. Carcinomatous component was not recognized. The histologic diagnosis was storiform-pleomorphic MFH. Tumor cells were positive for pancytokeratins AE1/3, KL-1, and CAM5.2 and cytokeratin (CK) 18, vimentin, CD68, p53, Ki-67 (labeling, 90%), α₁-antitrypsin, and α₁-antichymotrypsin and negative for pancytokeratin WSS, CK 34βE14, CK7, CK8, CK14, CK19, CK20, epithelial membrane antigen, S-100 protein, desmin, α-smooth muscle actin, CD34, HMB45, chromogranin, synaptophysin, myoglobin, CD45, CD30, and CD15. Because keratins were positive in tumor cells, a diagnosis of sarcomatoid carcinoma simulating MFH was made. The patient was treated with chemoradiation without significant effect and died 9 months after initial examination.

Sinonasal carcinomas: recent advances in molecular and phenotypic characterization and their clinical implications

Sinonasal carcinomas are rare tumors with an aggressive clinical behaviour which frequently pose a number of problems regarding the interpretation of diagnostic findings and the treatment. In addition, in comparison with other malignancies of the head and neck region, an elevated fraction of sinonasal carcinomas can be attributed to occupational exposure. This review is focused on the recent advances in the molecular and phenotypic characterization of sinonasal carcinomas, and their possible implications for the interpretation of epidemiological data, as well as for the diagnosis and treatment of these rare malignancies. The increasing knowledge on their phenotypic and genotypic features is progressively leading to a refinement in diagnosis, especially for poorly differentiated and undifferentiated lesions, as well as to the identification of markers which can be potentially useful to identify the early phases of carcinogenesis, to detect subclinical disease, to predict the response to therapy, and finally, that may represent potential targets for alternative treatments.

HPV-positive/p16-positive/EBV-negative nasopharyngeal carcinoma in white North Americans

BACKGROUND

Human papillomavirus (HPV) has been detected in keratinizing nasopharyngeal carcinomas (NPCs); however, the relationship between HPV and Epstein-Barr virus (EBV) among whites with nonkeratinizing NPCs remains unclear. The HPV, p16, and EBV status was examined in current University of Michigan patients with NPC.

METHODS

From 2003 to 2007, 89 patients, 84 with oropharyngeal cancer (OPC) and 5 with NPC, were enrolled in an organ-sparing trial. Biopsy tissues from all 89 patients were evaluated for HPV and p16 expression. A separate HPV analysis of the 84 OPC patients is in progress. Among the patients with NPC, tumor tissue was also analyzed for EBV-encoded RNA (EBER).

RESULTS

Five of 89 patients (5.6%) had NPC, all with nonkeratinizing histology. The 4 white patients with NPC were HPV(+) (subtype-16, subtype-18 [2 patients], and subtype-59)/p16(+)/EBER(-). One Asian patient with NPC had an HPV(-)/p16(-)/EBER(+) NPC tumor that developed distant metastases.

CONCLUSION

We postulate that HPV may be the etiologic factor in some EBV-negative, nonkeratinizing NPCs among whites.

Lymphoepithelioma-like carcinoma of the ovary

Only one case of lymphoepithelioma-like carcinoma of the ovary has been reported so far. A new case is herein illustrated in a 69-year-old woman: an ovarian mass adherent to urinary bladder dome with peritoneal carcinomatosis. Histologically, undifferentiated carcinomatous areas were intermingled with abundant lymphoid tissue. Epstein-Barr virus has not been detected either in neoplastic or in lymphoid cells.

The small round blue cell tumors of the sinonasal area

The diagnostic classification of small round blue cell tumors of the sinonasal area to include diverse malignancies of epithelial, hematolymphoid, neuroectodermal, and mesenchymal origin is challenging to the surgical pathologist using conventional histopathologic approaches because the cytomorphologic features are often overlapping or indistinctive. Rare or occasional clinical presentations in atypical age groups or unusual locations, as well as small biopsy samples may further complicate the differential diagnosis. Immunohistochemistry represents an extensively investigated ancillary technique that may aid in the provision of a definitive diagnosis. In recent years, certain small round blue cell tumors have been shown by cytogenetic analysis to have specific and primary chromosomal alterations, providing clinicians with a valuable tool to enhance their diagnostic armamentarium. The addition of molecular cytogenetic [fluorescence in situ hybridization (FISH), comparative genomic hybridization (CGH)] and molecular pathologic [polymerase chain reaction (PCR) and reverse transcriptase (RT)-PCR] approaches has further enhanced the sensitivity and accuracy of detecting these genetic alterations including assessment in formalin-fixed, paraffin-embedded tissues. Establishing an accurate diagnosis of a small round blue cell tumor of the sinonasal tract frequently requires adjunctive studies including immunohistochemical and molecular analyses.

[Undifferentiated malignant round cell tumors of the sinonasal tract and nasopharynx]

Undifferentiated malignant round cell tumors of the sinonasal tract and nasopharynx comprise of aggressive malignant neoplasms with overlapping morphologic features, which yet are very different and can be identified as carcinoma, lymphoma, sarcoma, melanoma or olfactory neuroblastoma. Differentiating these tumors is important because their treatment and prognosis are quite different. Because of the limited initial biopsy tissue materials, major differential diagnostic difficulties may arise. The use of a panel of immunohistochemical markers and the identification, in some cases, of specific chromosomal translocations are most often required. We describe clinical, morphological, immunohistochemical and molecular features as well as therapeutic management and prognosis of rhabdomyosarcoma (RMS), Ewing sarcoma/primitive neuroectodermic tumor (EWS/PNET), nonkeratinizing nasopharyngeal carcinoma, undifferentiated subtype (UCNT), olfactory neuroblastoma (ONB), small cell carcinoma, neuroendocrine type (SCCNET), sinonasal undifferentiated carcinoma (SNUC) and mucosal melanoma. Mesenchymal chondrosarcoma, small round cell synovialosarcoma, lymphomas and plasmocytoma are not introduced. The most important features of diagnosis will be summarized in two tables.

Undifferentiated malignant neoplasms of the sinonasal tract

CONTEXT

The most commonly encountered malignant neoplasms of the sinonasal tract are the keratinizing and nonkeratinizing types of squamous cell carcinoma. However, this complex anatomic region may represent the site of aggressive, non-squamous cell epithelial and nonepithelial malignant neoplasms of varying histogenesis, which are grouped under the term undifferentiated malignant neoplasms. Frequently, these undifferentiated malignancies share clinical and light microscopic features, which makes differentiation of one from the other virtually impossible without the use of adjunct analyses (eg, immunohistochemistry, electron microscopy, or molecular biologic studies). These tumors often are clinically aggressive and usually fatal, despite all attempts at controlling disease. Nevertheless, differentiating these tumors has clinical import because advances in therapeutic intervention may increase survival with good quality of life, and in some instances may achieve a cure.

OBJECTIVE

To compare and contrast the clinical, light microscopic, and immunohistochemical features of sinonasal undifferentiated malignant neoplasms.

DATA SOURCES

Case-derived material and literature review.

CONCLUSIONS

A variety of undifferentiated malignant neoplasms occur in the sinonasal tract with overlapping clinical and pathologic findings. In limited biopsy material, differentiation of these tumor types can be challenging. The pathologist plays a primary role in establishing the correct diagnosis, which often necessitates the use of adjunct studies that allow for differentiating among these neoplasms.

Nasenhöhle und Nasennebenhöhlen

Die Gesichtsmitte (der Bezirk zwischen Oberlippe und Stirn) entwickelt sich zwischen der 4. und 8. Schwangerschaftswoche. [ 220] Der Stirnfortsatz bildet sich währen der 4. postovulatorischen Woche, aus ihm gehen die oberen und mittleren Anteile des Gesichts hervor. Die Oberkiefer- und Nasenwülste entwickeln sich unterhalb des Stirnfortsatzes. Am Ende der 4. Woche bilden zwei oberflächliche Verdickungen der Nasenwülste die Riechplakoden, die ektodermaler Herkunft sind und aus denen der Epithelbelag der Nasenhöhle und Nasennebenhöhlen hervorgeht. Die Plakoden stülpen sich ein und bilden die Riechgruben, aus denen die vorderen Choanen (Nasenlöcher) und weniger oberflächlich die primitiven hinteren Choanen entstehen. Die medialen Nasen- und Stirnfortsätze bilden das Nasenseptum, die Stirnknochen, Nasenknochen, die Siebbeinzellen- Komplexe und die oberen Schneidezähne. Die lateralen Nasen- und Oberkieferfortsätze vereinigen sich zur Bildung des Philtrum und der Columella. Das knorpelige Nasenskelet bildet sich während der 7. und 8. postovulatorischen Woche tief unterhalb der Nasen- und Stirnbeinknochen aus dem Chondrocranium. Die Nasennebenhöhlen entwickeln sich in der 6. Fetalwoche aus den lateralen Nasenwänden, und ihr Wachstum setzt sich nach der Geburt während des gesamten Kindes- und Jugendalters fort.