2026 Poster Presentations
P311: SINONASAL MYOPERICYTOMA: CASE SERIES AND LITERATURE REVIEW
Peter S Giannaris, BS1; Matthew Mendelsohn, MD2; Mostafa Kokabee, MD3; Shengjie Cui, MD, PHD3; Dominick Guerrero, MD3; Mark Chaskes, MD4; Judd Fastenberg, MD4; Charles C Tong, MD4; 1City University of New York School of Medicine; 2Department of Otolaryngology, State University of New York-Downstate Health Sciences University; 3Department of Pathology and Laboratory Medicine- Lenox Hill Hospital, Northwell Health; 4Department of Otolaryngology- Head and Neck Surgery, Northwell Health
Background: Myopericytoma (MPC) is a rare benign mesenchymal tumor characterized by perivascular proliferation of spindle cells with myoid differentiation. While MPC predominantly affects the extremities, sinonasal involvement is a rare clinical entity with unique diagnostic challenges. There are limited case reports describing sinonasal MPC, necessitating the need for a comprehensive literature review to guide clinical features and management.
Case Series: We report two cases on sinonasal MPC: a 67-year old male with an incidental 1.4 cm left nasal cavity mass arising from the inferior turbinate, and a 37-year old male that presented with recurrent epistaxis and a 0.6 cm right anterior nasal septal mass, initially diagnosed as a pyogenic granuloma. Both patients underwent successful endoscopic surgical excision. Histopathology revealed perivascular spindle cell proliferation with smooth muscle actin positivity, confirming MPC. At follow-up, both remained recurrence-free.
Methods: A literature review was conducted for articles published between 1998-2025 using PubMed, Embase, Cochrane, and Google Scholar databases. Search terms included “myopericytoma,” “sinonasal,” “head and neck,” and various combinations. Additional references were identified through bibliographies. Demographics, clinical presentation, treatment, immunohistochemical profiles, and outcomes were extracted.
Results: We identified five reported sinonasal MPC cases in the literature plus our two institutional cases, yielding 7 total cases. The mean age was 47.3 years with a female predominance (5/7, 71.4%). The nasal septum was the most affected site (n=3), followed by the nasal cavity floor (n=2) and inferior turbinate (n=2). Tumor size ranged from 0.5- to 1.5-cm. Clinical presentation included epistaxis in two patients, nasal obstruction in one patient, while three cases were asymptomatic. Histopathological examination revealed characteristic perivascular spindle cell proliferation with concentric arrangement around thin-walled vessels in all cases. Immunohistochemistry demonstrated smooth muscle actin positivity in all cases where reported, while CD34 and desmin expression showed variable patterns across the cohort. Complete surgical excision was achieved in all cases using endoscopic approaches, with specific techniques tailored to tumor location. One patient experienced recurrence following incomplete initial excision, while all cases with complete excision remained disease-free during available follow-up periods.
Conclusion: Sinonasal MPC represents a rare entity with significant diagnostic challenges due to morphological overlaps with common sinonasal vascular lesions. Accurate diagnosis requires comprehensive immunohistochemical evaluation, with smooth muscle actin positivity serving as the primary diagnostic marker, while CD34 and desmin show variable expression patterns. Complete endoscopic excision with histopathological confirmation and appropriate immunohistochemical staining is the optimal management, with surveillance recommended to detect any recurrence.