Expanding the Spectrum of Sarcoma with an Internal Tandem Duplication of BCOR: A Non-Pediatric Nasosinusal Case.

INTRODUCTION: Undifferentiated small round-cell sarcomas with BCL6 corepressor (BCOR) alterations, such as an internal tandem duplication (ITD) within exon 15, are typically described as a pediatric group of Ewing-like small round-cell sarcomas. CASE PRESENTATION: In contrast to this notion, we report the case of a 71-year-old woman with a nasosinusal sarcoma featuring a BCOR ITD. To the best of our knowledge, this presence had not been previously documented in a sarcoma of the nasal and sinus cavities in an elderly patient. The identified duplication shares a similar minimal critical region as described in clear-cell sarcomas of the kidney in children. This alteration, located within the PCGF1 binding domain, is believed to disrupt the activity of PRC1.1. CONCLUSION: This case underscores the need for in-depth research into the molecular biology of these rare tumors and explores potential alternative treatment options. The patient achieved remission after two cycles of doxorubicin and cyclophosphamide chemotherapy, highlighting the promise of potential therapeutic options for BCOR ITD sarcomas.

[Translocated sinonasal tumors]. / Tumeurs nasosinusiennes à translocation.

In recent years, several nasal cavity and sinus entities have been described with fusion genes. Salivary gland tumors with fusion genes will not be discussed in this article, but it should be kept in mind that accessory salivary glands are present in the nasal cavity and sinuses and can therefore lead to tumoral lesions. Entities with specific or more frequently described rearrangements in the nasal cavities and sinuses are DEK::AFF2 squamous cell carcinomas,;non-intestinal and non-salivary nasosinusal adenocarcinomas, some of which displaying ETV6 gene rearrangements; biphenotypic nasosinusal sarcomas, most of which displaying PAX3 gene rearrangements; and Ewing's adamantinoma-like sarcomas, which display the same rearrangements as conventional Ewing's sarcomas, mainly the EWSR1::FLI1 rearrangement. Each entity will be described morphologically, immunohistochemically, and prognostically.

Adult transverse sinus capillary hemangioma: case report and review of the literature.

BACKGROUND: Adult intracranial capillary hemangioma (ICH) is an extremely rare disease with very few cases reported in the literature. Natural history is poorly understood and therapeutic management has not been clearly defined. METHODS: Using PRISMA guidelines, we systematically reviewed all published adult cases of ICH, to which we added our own case. CASE PRESENTATION: A 24-year-old patient with intracranial hypertension underwent stenting for left transverse sinus ICH. Recurrence was managed by subtotal resection, and radiotherapy was undertaken after a second relapse. Radiotherapy achieved complete response at last follow-up. RESULTS: Among cases of ICH found in the literature, 36 concerned adults (55.3%), with clear female predominance, and only 2 cases affecting the transverse sinus (8.1%). Adult ICHs grew over time, and pregnancy seemed to accelerate natural progression. Complete resection was achieved in most cases, and radiotherapy was used in case of relapse, with high rates of tumor control. CONCLUSION: Transverse sinus ICH is uncommon, and venous stenting is a suitable option in case of tumor invasion to treat intracranial hypertension. Surgery is the gold-standard treatment, and radiotherapy is a very effective alternative, with high rates of tumor control. Natural history is not benign, particularly in case of pregnancy.

Sinonasal Squamous Cell Carcinoma with DEK::AFF2 Rearrangement: An Aggressive Cancer with Bland Morphology.

AIMS: DEK::AFF2 squamous cell carcinoma is a recently described cancer entity, with 29 cases reported to date. Occasionally, these carcinomas appear deceptively indistinguishable; however, specific morphological and phenotypic features suggest the presence of this rearrangement. However, the prognostic value of this diagnosis remains unclear. We aimed to report a new case series with histological, molecular, and clinical features. METHODS: We collected data from 15 patients and investigated their phenotypes, including the expression profiles of CK7, P63/P40, PDL1, AFF2, and P16, morphological features, and associated prognostic data. We analyzed these data along with the previously published data. RESULTS: Most of these cases exhibited indicative morphological features, such as exophytic and endophytic papillary growth, nuclear monomorphism, and abundant neutrophil-rich inflammatory infiltrates. Immunohistochemical analysis revealed the expression of AFF2 and squamous cell markers in all the patients. Overexpression of P16 was not detected, whereas CK7 and PDL1 were expressed variably. In our study cohort, a 50% progression or recurrence rate, 25% lymph node metastasis, 17% distant metastasis, and 18% disease-related death were identified, with a short follow-up time. CONCLUSION: DEK::AFF2 squamous cell carcinoma incidence is probably underestimated. The low-grade appearance of these tumors sometimes limits their detection. The rates of recurrence and metastasis seem to be high despite an often bland morphology. We propose AFF2 immunohistochemistry as an effective tool, and a diagnostic algorithm has been established to support accurate diagnosis of these tumors.

High-grade non-intestinal type sinonasal adenocarcinoma with ETV6::NTRK3 fusion, distinct from secretory carcinoma by immunoprofile and morphology.

We report 2 cases of high-grade sinonasal adenocarcinoma with a distinct morphological and immunohistochemical phenotype. Albeit histologically different from secretory carcinoma of the salivary glands, both tumors presented here share an ETV6::NTRK3 fusion. The highly cellular tumors were composed of solid and dense cribriform nests, often with comedo-like necroses in the center, and minor areas with papillary, microcystic, and trabecular formations without secretions, mostly located at the periphery of the lesion. The cells displayed high-grade features, with enlarged, crowded, and often vesicular nuclei with conspicuous nucleoli and brisk mitotic activity. The tumor cells were immunonegative for mammaglobin while showing immunopositivity for p40/p63, S100, SOX10, and GATA3, as well as for cytokeratins 7, 18, and 19. For the first time, we describe 2 cases of primary high-grade non-intestinal type adenocarcinomas of the nasal cavity, distinct from secretory carcinoma by morphology and immunoprofile, harboring the ETV6::NTRK3 fusion.