Abstract

Background: Paraganglioma of the bladder is an extremely rare tumor, accounting for less than 0.06% of bladder tumors. Due to nonspecific symptoms and imaging, it is often misdiagnosed as urothelial carcinoma, causing a risk of serious cardiovascular complications during intervention. Case report: A 56-year-old male patient with a history of hypertension and diabetes mellitus, presenting with hematuria and dysuria. Magnetic resonance imaging showed a left-sided bladder wall with a tumor (10 x 14 x 15 mm) near the bladder neck, with smooth borders and protruding into the bladder lumen. Cystoscopy revealed a tumor at the 12 o’clock position, close to the bladder neck The patient had a tumor (30 x 10 mm) with a broad stalk and polyp-like appearance. The patient underwent transurethral resection of the bladder tumor (TURBT). Histopathological findings showed tumor cells with small, uniform nuclei; broad, granular cytoplasm arranged in clusters, separated by highly vascular fibrous septa, suggesting a “Zellballen” structure. Immunohistochemistry was strongly positive and diffuse for Chromogranin; positive for S100 and negative for Synaptophysin, CK, and GATA3. Diagnosis is bladder paraganglioma, PASS: 0 points. Conclusion: The definitive diagnosis of bladder paraganglioma is based primarily on histopathological and immunohistochemical characteristics. TURBT surgery is an effective option for small tumors (< 30 mm). The application of the Grading system for Adrenal Pheochromocytoma and Paraganglioma (GAPP) is necessary in predicting metastatic potential. Follow-up should be performed periodically, for at least 10 years.