A case report of sinonasal glomangiopericytoma: An important reminder to always collect specimen.

OBJECTIVES: To present a case report of sinonasal glomangiopericytoma (GPC) in a female patient in her thirties and to highlight the importance of collecting pathology specimens even in routine sinus surgery cases. METHODS: A case report detailing the diagnosis of GPC in a female in her thirties, including her initial presentation, treatment, and follow-up, along with a brief review of the literature. RESULTS: Pathology of the collected specimen revealed sinonasal GPC along with chronic rhinosinusitis. Immunohistochemistry was positive for SMA, beta-catenin, and cyclin D1; and negative for STAT6, ERG, pankeratin, SOX10, and S100. CONCLUSION: This diagnosis expands the knowledge around the demographic profile of GPC patients. GPC should be included in the differential diagnosis of sinonasal masses, even in younger patients. The case highlights the importance of collecting the entire pathology specimen in all cases, even of ones that seem routine and benign.

A Pilot Immunohistochemical Study Identifies Hedgehog Pathway Expression in Sinonasal Adenocarcinoma.

Tumors of the head and neck, more specifically the squamous cell carcinoma, often show upregulation of the Hedgehog signaling pathway. However, almost nothing is known about its role in the sinonasal adenocarcinoma, either in intestinal or non-intestinal subtypes. In this work, we have analyzed immunohistochemical staining of six Hedgehog pathway proteins, sonic Hedgehog (SHH), Indian Hedgehog (IHH), Patched1 (PTCH1), Gli family zinc finger 1 (GLI1), Gli family zinc finger 2 (GLI2), and Gli family zinc finger 3 (GLI3), on 21 samples of sinonasal adenocarcinoma and compared them with six colon adenocarcinoma and three salivary gland tumors, as well as with matching healthy tissue, where available. We have detected GLI2 and PTCH1 in the majority of samples and also GLI1 in a subset of samples, while GLI3 and the ligands SHH and IHH were generally not detected. PTCH1 pattern of staining shows an interesting pattern, where healthy samples are mostly positive in the stromal compartment, while the signal shifts to the tumor compartment in tumors. This, taken together with a stronger signal of GLI2 in tumors compared to non-tumor tissues, suggests that the Hedgehog pathway is indeed activated in sinonasal adenocarcinoma. As Hedgehog pathway inhibitors are being tested in combination with other therapies for head and neck squamous cell carcinoma, this could provide a therapeutic option for patients with sinonasal adenocarcinoma as well.

BiZact-Assisted Endoscopic Resection of a Sinonasal Tumor.

The BiZact device, a bipolar electrosurgical scissor designed for tonsillectomy, minimizes thermal tissue damage and seals blood vessels <3 mm in diameter while dividing the soft tissue. This study describes the authors' experience with sinonasal tumor surgery using a BiZact and discusses its clinical utility and advantages. The authors analyzed BiZact-assisted endoscopic sinonasal tumor surgery cases between January 2021 and May 2023. Data were collected on patients' demographics, histopathology, extent of tumor involvement, surgical records, and postoperative medical records. Clinical utility was assessed using the success rate of complete tumor excision, estimated blood loss during surgery, device-related complications, and operation time. A survey of the surgeons' BiZact experience was also conducted. The diagnoses of the 20 patients in this study included squamous cell carcinoma (n = 2), malignant melanoma (n = 1), sarcoma (n = 1), natural killer cell lymphoma (n = 1), inverted papilloma (n = 12), angiofibroma (n = 2), and schwannoma (n = 1). This pilot study demonstrated a shortened operative time, with a median of 0.8 hours and <100 mL of intraoperative blood loss. In addition, no BiZact-related complications were observed. The BiZact device allows efficient sinonasal surgery because it has the unique advantage of one-step sealing and cutting. BiZact-assisted endoscopic sinonasal tumor surgery is a beneficial and safe procedure that reduces blood loss during surgery, shortens the operative time, and minimizes postoperative complications.

Evaluation of Some Prognostic Biomarkers in Human Papillomavirus-Related Multiphenotypic Sinonasal Carcinoma.

Background: Human papillomavirus (HPV)-related multi phenotypic sinonasal carcinoma (HMSC) is a recently described tumor subtype with an unknown prognosis, often misdiagnosed with other sinonasal carcinomas, and associated with high-risk HPV (HR-HPV). The present study aimed to evaluate the expression of vascular endothelial growth factor (VEGF), Bcl-2-associated X protein (BAX), epidermal growth factor receptors (EGFR), ProExTMC, and human telomerase reverse transcriptase (hTERT) and assess their association with survival and clinicopathological characteristics. Methods: Between 2017 and 2022, 40 HMSC patients underwent surgical resection at the School of Medicine, Zagazig University Hospitals (Zagazig, Egypt). Tissue samples were examined for the presence of HR-HPV; absence of myeloblastosis (MYB), MYB proto-oncogene like 1 (MYBL1), and nuclear factor I/B (NFIB) fusions and the presence of myoepithelial proteins (calponin, S100, SMA), squamous differentiation markers (p63, p40, calponin), VEGF, BAX, ProExTMC, and hTERT by immunohistochemistry. All patients were followed up for about 54 months until death or the last known survival data. Data were analyzed using the Chi square test and Kaplan-Meier method. Results: The expression of VEGF, hTERT, and ProExTMC was significantly associated with age, advanced tumor stages, lymph node metastasis, tumor size, mortality, relapse, poor disease-free survival (DFS), and overall survival (OS) (P<0.001). BAX expression was significantly associated with tumor size, age, poor DFS, and relapse (P=0.01, P<0.001, P=0.035, and P=0.002, respectively). Conclusion: HMSC is strongly associated with HR-HPV. The expression of VEGF, EGFR, BAX, hTERT, and ProExTMC is associated with aggressive malignant behavior, poor survival, and poor prognosis, making them novel prognostic biomarkers for targeted therapeutics in HMSC.

Neoadjuvant Chemotherapy in Locally Advanced Sinonasal Teratocarcinosarcoma a Rare Malignancy: An Audit From an Academic Tertiary Care Centre in India.

AIMS: Sinonasal teratocarcinosarcomas (SNTCS) are rare sinonasal malignancies, the incidence of which is less than 1% of all tumors. There is limited data available on SNTCS's, often as case reports and small case series. The management of SNTCS is complicated because of its location, locally aggressive biology, difficulty in achieving complete resection, and limited data on chemotherapy in these malignancies. This audit was performed to understand the role of neoadjuvant chemotherapy (NACT) in SNTCS's, its ability to downstage the disease, achieve complete resection, and impact on long-term survival outcomes. METHODS: This was a retrospective analysis of a prospectively maintained database approved by the Institutional Ethics Committee (IEC). The baseline characteristics, the extent of tumor, Kadish stage, NACT regimen, and adverse events were extracted from the Electronic Medical Records and the patient's case file. Patients with baseline extensive/inoperable disease were referred for NACT from the multidisciplinary joint clinic followed by response assessment (RECIST v1.1). Patients underwent skull-base surgery if respectable post-completion of NACT, however, if deemed unresectable were treated with non-surgical modalities or palliative therapies. RESULTS: The data of 27 patients were evaluated from the year 2015-2022. The median age was 42 years (IQR:30-56) and 85.2% (n = 23) were males. The ECOG-PS was 0-1 in 88.8% (n = 24) patients. All 27 patients received NACT in view of extensive disease at presentation. 74.1% (n = 20) patients received Cisplatin-Etoposide and 25.9% (n = 7) received other chemotherapy regimens. The median number of chemotherapy cycles was 2(IQR:2-3). 96.3% patients (n = 26) completed the planned NACT cycles. 70.4% (n = 19) patients achieved a partial response in post-NACT imaging. 77.8% (n = 18) underwent surgery, 18.5% (n = 5) received CTRT, and 7.4% (n = 2) received definitive-RT alone. The median PFS and OS of the cohort was 19months (95%CI:12.0-25.6) and 23months (95%CI:5.94-40.06) respectively. CONCLUSION: NACT is safe, feasible, and effective with significant response rates, leading to effective downstaging, resectability and improved survival in patients with locally advanced SNTCS's.

Twelve years after: The french national network on rare head and neck tumours (REFCOR).

BACKGROUND: Rare cancers constitute less than 10% of head and neck cancers and lack sufficient evidence for standardized care. The French Rare Head and Neck Cancer Expert Network (REFCOR) as established a national database to collect data on these rare cancers. This study aims to describe patient and tumour characteristics in this database. METHODS: Prospective data collection was conducted across multiple centers. Survival analyses were performed using Kaplan Meier method and Log Rank test. Odds ratios were used for comparing proportions. RESULTS: A total of 7208 patients were included over a period of 10 years. The most frequent histologies were: Not Otherwise Specified (NOS) adenocarcinoma 13 %, adenoid cystic carcinoma 12 %, squamous cell carcinoma of rare locations 10 %, mucoepidermoid carcinoma 9 %, intestinal-type adenocarcinoma (8 %). Tumours were located in sinonasal area (38 %); salivary glands (32 %); oral cavity / oropharynx / nasopharynx (16 %); larynx / hypopharynx (3 %); ears (1 %); others (3 %). Tumours were predominantly classified as T4 (23 %), N0 (54 %), and M0 (62 %). Primary treatment approach involved tumour resection (78 %) and / or radiotherapy (63 %). Patients with salivary gland cancers exhibited better 5-year overall survival (OS) rates (p < 0.05), and lower recurrence rates compared to patients with sinonasal, laryngeal/ hypopharyngeal cancers. No significant differences were observed in the other comparisons. Acinar cell carcinoma demonstrated the best OS while mucous melanoma had the poorest prognosis. CONCLUSION: Melanoma, carcinoma NOS, and sinonasal undifferenciated carcinoma still have poor prognoses. Efforts are being made, including training and guidelines, to expand network coverage (REFCOR, EURACAN), improve data collection and contribute to personalized therapies.

Sinonasal Tumors Masquerading as Invasive Fungal Sinusitis (IFS).

OBJECTIVES: Fungal tissue invasion in the setting of sinonasal malignancy has been rarely described in the literature. Only a handful of studies have discussed cases of suspected chronic and acute IFS (CIFS and AIFS, respectively), having an underlying undifferentiated sinonasal carcinoma, sinonasal teratocarcinosarcoma, and NK/T-cell lymphoma. METHODS: Here, we describe 3 cases of carcinoma mimicking IFS from a single institution. RESULTS: Each of our patients presented with sinonasal complaints as an outpatient in the setting of immunosuppression. Intranasal biopsies consistently were predominated by necrotic debris, with and without fungal elements, ultimately leading to a delay of oncologic care. The final pathologies included NK/T-cell lymphoma and SNEC. All patients were followed by radiation and chemotherapy, with 1 case of mortality. CONCLUSIONS: We aim to emphasize the importance of obtaining viable tissue as pathology specimens as the presence of necrosis with fungal elements may limit the diagnosis and ultimately delay the care of an underlying sinonasal carcinoma.

Spindle Cell Tumors of the Sinonasal Tract: A Diagnostic Update with Focus on Ancillary Workup.

Spindle cell neoplasms arising in the head and neck may be challenging to recognize due to their relative rarity. While underlying molecular alterations are increasingly elucidated, testing for these features may not be readily available. In most cases, combinations of key morphologic features and diagnostic immunohistochemical markers can be used to replace molecular diagnostics. Conversely, some molecular alterations and expression of their surrogate biomarkers are not specific for any one entity, and it is important to recognize these to avoid diagnostic pitfalls. In this review, we discuss both old and new spindle cell tumors of the sinonasal tract, with an emphasis on histologic features and clinically relevant immunohistochemical markers serving as surrogate markers for underlying genomic alterations.

Radiotherapy Results in Locally Advanced Sinonasal Cancer: Turkish Society for Radiation Oncology, Head and Neck Study Group 01-005.

OBJECTIVES: This study aims to examine the treatment outcomes and related factors in locally advanced sinonasal cancer across Turkiye. METHODS: Twelve centers participants of the Turkish Society for Radiation Oncology Head and Neck Study Group attended the study. One hundred and ninety-four patients treated with intensity-modulated radiation therapy between 2001 and 2021 were analyzed retrospectively. The survival analysis was performed using the Kaplan-Meier method. Acute and late toxicity were recorded per Common Toxicity Criteria for Adverse Events V4.0. RESULTS: The median age was 58 years and 70% were male. The majority of tumors were located in maxillary sinus (59%). Most of the patients (%83) had T3 and T4A disease. Fifty-three percent of patients were in stage 4A. Radiotherapy was administered to 80% of the patients in the adjuvant settings. Median 66 Gy dose was administered in median 31 fractions. Chemotherapy was administered concomitantly with radiotherapy in 45% of the patients mostly with weekly cisplatin. No grade ≥4 acute and late toxicity was observed. The median follow-up was 43 months. The 5-year and 10-year overall survival (OS); locoregional recurrence-free survival (LRFS); distant metastasis-free survival (DMFS), and progression-free survival (PFS) rates were 61% and 47%; 69% and 61%; 72%, and 69%, and 56% and 49%, respectively. In the multivariate analysis, several factors demonstrated significant influence on OS, such as performance status, surgery, and lymph node involvement. Moreover, surgery was the key prognostic factor for LRFS. For DMFS, lymph node involvement and surgical margin were found to be influential factors. In addition, performance status and lymph node involvement were identified as significantly affecting PFS. CONCLUSIONS: In our study, the authors obtained promising results with IMRT. Performance status, lymph node involvement, and surgery emerged as the primary factors significantly influencing OS.

Sinonasal teratocarcinosarcoma in an adolescent male: A case report of an unusual neoplasm.

ABSTRACT: Sinonasal teratocarcinosarcoma (SNTCS) is an extremely rare and aggressive malignant tumor arising in the sinonasal tract, having a combined clinicopathological feature of teratoma and carcinosarcoma. It shows a male predominance and affects adults with an age range of 18-79 years and a mean age of 60 years. Here, we report a case of SNTCS in a 14-year-old male patient who presented with swelling over the upper right alveolus and pain in the right jaw for 2 months. The tumor was completely removed by right total maxillectomy with orbital mess reconstruction, and postoperative radiotherapy with chemotherapy was given. The follow-up of the patient for 2 years has shown evidence of recurrence and is now on palliative care.

Recurrent Wnt Pathway and ARID1A Alterations in Sinonasal Olfactory Carcinoma.

Sinonasal tumors with neuroepithelial differentiation, defined by neuroectodermal elements reminiscent of olfactory neuroblastoma (ONB) and epithelial features such as keratin expression or gland formation, are a diagnostically challenging group that has never been formally included in sinonasal tumor classifications. Recently, we documented that most of these neuroepithelial neoplasms have distinctive histologic and immunohistochemical findings and proposed the term "olfactory carcinoma" to describe these tumors. However, the molecular characteristics of olfactory carcinoma have not yet been evaluated. In this study, we performed targeted molecular profiling of 23 sinonasal olfactory carcinomas to further clarify their pathogenesis and classification. All tumors included in this study were composed of high-grade neuroectodermal cells that were positive for pankeratin and at least 1 specific neuroendocrine marker. A significant subset of cases also displayed rosettes and neurofibrillary matrix, intermixed glands with variable cilia, peripheral p63/p40 expression, and S100 protein-positive sustentacular cells. Recurrent oncogenic molecular alterations were identified in 20 tumors, including Wnt pathway alterations affecting CTNNB1 (n = 8) and PPP2R1A (n = 2), ARID1A inactivation (n = 5), RUNX1 mutations (n = 3), and IDH2 hotspot mutations (n = 2). Overall, these findings do demonstrate the presence of recurrent molecular alterations in olfactory carcinoma, although this group of tumors does not appear to be defined by any single mutation. Minimal overlap with alterations previously reported in ONB also adds to histologic and immunohistochemical separation between ONB and olfactory carcinoma. Conversely, these molecular findings enhance the overlap between olfactory carcinoma and sinonasal neuroendocrine carcinomas. A small subset of neuroepithelial tumors might better fit into the superseding molecular category of IDH2-mutant sinonasal carcinoma. At this point, sinonasal neuroendocrine and neuroepithelial tumors may best be regarded as a histologic and molecular spectrum that includes core groups of ONB, olfactory carcinoma, neuroendocrine carcinoma, and IDH2-mutant sinonasal carcinoma.

Integrated Molecular and Histological Insights for Targeted Therapies in Mesenchymal Sinonasal Tract Tumors.

PURPOSE OF REVIEW: This review aims to provide a comprehensive overview of mesenchymal sinonasal tract tumors (STTs), a distinct subset of STTs. Despite their rarity, mesenchymal STTs represent a unique clinical challenge, characterized by their rarity, often slow progression, and frequently subtle or overlooked symptoms. The complex anatomy of the sinonasal area, which includes critical structures such as the orbit, brain, and cranial nerves, further complicates surgical treatment options. This underscores an urgent need for more advanced and specialized therapeutic approaches. RECENT FINDINGS: Advancements in molecular diagnostics, particularly in next-generation sequencing, have significantly enhanced our understanding of STTs. Consequently, the World Health Organization has updated its tumor classification to better reflect the distinct histological and molecular profiles of these tumors, as well as to categorize mesenchymal STTs with greater accuracy. The growing understanding of the molecular characteristics of mesenchymal STTs opens new possibilities for targeted therapeutic interventions, marking a significant shift in treatment paradigms. This review article concentrates on mesenchymal STTs, specifically addressing sinonasal tract angiofibroma, sinonasal glomangiopericytoma, biphenotypic sinonasal sarcoma, and skull base chordoma. These entities are marked by unique histopathological and molecular features, which challenge conventional treatment approaches and simultaneously open avenues for novel targeted therapies. Our discussion is geared towards delineating the molecular underpinnings of mesenchymal STTs, with the objective of enhancing therapeutic strategies and addressing the existing shortcomings in the management of these intricate tumors.

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

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

Choice of surgery in intestinal-type adenocarcinoma of the sinonasal tract: a long-term comparative study.

PURPOSE: Intestinal-type adenocarcinoma (ITAC) is a rare sinonasal malignancy. Curative treatment requires multidisciplinary approach, with surgical options consist of the endonasal endoscopic approach (EEA) and external surgery (EXTS). Here, we provide the post-operative and survival results from a single-center long-term follow-up. METHODS: We report long-term follow-up of 92 ITAC cases treated between 1998 and 2018, treated with EEA (n = 40) or EXTS (n = 52). Survival estimates, post-operative complications and duration of hospitalization were compared between surgical modalities. RESULTS: Baseline characteristics were similar. A higher number of T4b tumors (16%), and subsequently more tumoral invasion (39%), was present in patients undergoing EXTS compared to EEA (3% and 18%, respectively). No difference in Barnes histology subtypes was noticed. Patients undergoing EEA had a shorter post-operative hospitalization stay versus EXTS (4 versus 7 days). Use of EEA was associated to improved disease-specific survival (DSS; 11.4 versus 4.4 years; HREEA = 0.53), especially for patients with T3-4a tumors (11.4 versus 3.0 years; HREEA = 0.41). Patients with T3-4 stage, tumoral invasion, positive surgical margins, mucinous or mixed histology, and prolonged post-operative hospital stay showed poor local relapse-free, disease-free, overall, and DSS. CONCLUSIONS: Long-term follow-up in locally advanced ITAC demonstrates that resection by EEA is correlated with improved DSS compared to EXTS, especially for T3-4 tumors. No significant differences between both treatment modalities was observed regarding per- and post-operative complications, although hospitalization in patients undergoing EEA was shorter than for patients treated with EXTS. These results confirm that EEA should remain the preferred surgical procedure in operable cases of sinonasal ITAC.

Evaluation of narrow-band imaging in the diagnosis of sinonasal inverted papilloma.

KEY POINTS: Narrow-band imaging (NBI) can be used to differentiate benign sinonasal lesions NBI can be used in the preoperative identification of sinonasal inverted papilloma Future studies can focus on NBI for recurrent inverted papilloma and surgical margin guidance.

A multi-institutional retrospective study of 340 cases of sinonasal malignant tumor.

OBJECTIVE: Sinonasal malignant tumors (SNMT) are relatively rare among head and neck malignant tumors. Most are squamous cell carcinomas, and malignant melanomas, olfactory neuroblastomas, adenoid cystic carcinomas, sarcomas, and others also occur. The most common primary site of nasal sinus squamous cell carcinoma is the maxillary sinus. In recent years, a decrease in incidence of maxillary sinus squamous cell carcinoma (MSSCC) has been reported along with a decrease in the incidence of sinusitis. MSSCC is treated with a combination of surgery, radiation, and chemotherapy. Treatment decisions are made according to the progression of the disease, the patient's general condition, and the patient's own wishes. There are variations in treatment policies among facilities due to the specialty of staff and cooperation with other departments at each facility. We conducted a multi-institutional retrospective study to compare outcomes by treatment strategy. METHODS: In this study, 340 patients with SNMT who were treated at 13 Hospitals (Head and Neck Oncology Group (Kyoto-HNOG) ) during the 12-year period from January 2006 to December 2017 were included. There were 220 patients with squamous cell carcinoma, 32 with malignant melanoma, 21 with olfactory neuroblastoma, and 67 with other malignancies. Of the squamous cell carcinomas, 164 were of maxillary sinus origin. One hundred and forty cases of MSSCC that were treated radically were included in the detailed statistical analysis. RESULTS: There were 5 cases of cStage I, 9 cases of cStage II, 36 cases of cStage III, 74 cases of cStage IVa, and 16 cases of cStage IVb. There were 92 cases without clinical lymph node metastasis (cN(-)) and 48 cases with clinical lymph node metastasis(cN(+)). Primary tumors were treated mainly by surgery in 85 cases (Surg) and by radical radiation therapy (with or without chemotherapy) of 6-70 Gy in 55 cases(non-Surg). The 5-year overall/disease-free survival rate (OS/DFS) for MSSCC was 65.1%/51.6%. Old age, renal dysfunction, and clinical T progression were independent risk factors for OS, and renal dysfunction was an independent risk factor for DFS. In cN(-) patients, OS and DFS were significantly better in Surg group than in non-Surg group. In cN(+) patients, there was no significant difference in OS and DFS between Surg and non-Surg groups. CONCLUSION: For patients with MSSCC without lymph node metastasis, aggressive surgery on the primary tumor contributes to improved prognosis.

FGFR1/2/3-rearranged carcinoma of the head and neck: expanded histological spectrum crossing path with high-risk HPV in the sinonasal tract.

AIMS: Oncogenic FGFR1/2/3 rearrangements are found in various cancers. Reported cases in head and neck (HN) are mainly squamous cell carcinomas (SCCs) with FGFR3::TACC3 fusions, a subset of which also harbour high-risk human papillomavirus (HPV). However, the knowledge of the clinicopathological spectrum of FGFR-rearranged head and neck carcinomas (FHNC) is limited. METHODS AND RESULTS: A retrospective MSK-fusion clinical sequencing cohort 2016-23 was searched to identify malignant tumours in the HN region harbouring FGFR1/2/3 fusion. FHNC were characterised by histological examination, immunohistochemistry and molecular analysis. Electronic medical records were reviewed. Three FHNC were identified. Two cases (cases 1 and 2) involved sinonasal tract and were high-grade carcinomas with squamous, basaloid, glandular and/or ductal-myoepithelial features. Case 1 arose in a 79-year-old man and harboured FGFR2::KIF1A fusion. Case 2 arose in a 58-year-old man, appeared as HPV-related multiphenotypic sinonasal carcinoma (HMSC), and was positive for FGFR2::TACC2 fusion and concurrent high-risk HPV, non-type 16/18. Case 3 was FGFR3::TACC3 fusion-positive keratinising SCCs arising in the parotid of a 60-year-old man. All three cases presented at stage T4. Clinical follow-up was available in two cases; case 1 remained disease-free for 41 months post-treatment and case 3 died of disease 2 months after the diagnosis. CONCLUSIONS: FHNC include a morphological spectrum of carcinomas with squamous features and may occur in different HN locations, such as parotid gland and the sinonasal tract. Sinonasal cases can harbour FGFR2 rearrangement with or without associated high-risk HPV. Timely recognition of FHNC could help select patients potentially amenable to targeted therapy with FGFR inhibitors. Further studies are needed (1) to determine if FGFR2 rearranged/HPV-positive sinonasal carcinomas are biologically distinct from HMSC, and (2) to elucidate the biological and clinical significance of FGFR2 rearrangement in the context of high-risk HPV.