A rare case of sinonasal paraganglioma: clinical presentation, multimodal management, and literature review

Sinonasal paraganglioma (SNP) is an exceptionally rare neuroendocrine tumor characterized by nonspecific symptoms and significant hypervascularity, posing considerable diagnostic and therapeutic challenges. This report presents the case of a 32-year-old female with a 5-month history of progressive unilateral nasal obstruction, purulent discharge, and recurrent epistaxis. Nasal endoscopy revealed a hyperemic, friable mass occupying the left common and middle meatus. Preoperative imaging, including computed tomography (CT) and magnetic resonance imaging (MRI), identified a well-defined, intensely enhancing lesion with characteristic gyriform pattern involving the left middle and superior meatus, extending into adjacent sinuses and causing focal erosion of the anterior skull base. The patient underwent complete endoscopic resection without preoperative embolization, with an estimated blood loss of 300 mL. Histopathological examination confirmed the diagnosis, demonstrating the classic nested (Zellballen) architecture. Immunohistochemistry was positive for synaptophysin, chromogranin A, and CD56 in chief cells, with S-100 protein highlighting sustentacular cells. SDHB expression was retained, and the Ki-67 proliferation index was approximately 15%. The postoperative course was uneventful, with no evidence of recurrence at the 6-month follow-up. This case highlights the importance of considering SNP in the differential diagnosis of unilateral hypervascular nasal masses. Definitive diagnosis relies on histopathology and immunohistochemistry. Endoscopic resection is the treatment of choice, with preoperative embolization recommended for large or highly vascularized tumors to mitigate intraoperative hemorrhage. Given the potential for hereditary syndromes and late recurrence, genetic counseling and long-term surveillance are essential components of comprehensive management.