Paragangliomas (PGLs) are rare extra-adrenal neuroendocrine tumors, accounting for approximately 0.7% of all PGLs. Previous studies have shown that the clinical presentation of PGLs varies depending on catecholamine excess, tumor location, and size. Many cases are incidentally detected through imaging studies. This report presents a rare case encountered in our clinical practice.

A 57-year-old female with a history of hypertension underwent a routine physical examination, during which an abdominal CT scan revealed a suspected bladder tumor. A CT-guided biopsy was performed, and histopathology confirmed the diagnosis of paraganglioma. Upon further inquiry, the patient reported occasional palpitations upon waking in the morning. After discussing treatment options, robotic-assisted partial cystectomy was performed. Pathological analysis confirmed paraganglioma with lymphovascular invasion, loss of succinate dehydrogenase B (SDHB) expression on immunohistochemical staining, and a Ki-67 labeling index of approximately 8.7%. The patient had an uneventful postoperative recovery. She is currently under regular follow-up at our outpatient department.

This case highlights the possibility of mild or even absent symptoms of catecholamine excess in patients with bladder paraganglioma. Previous studies have shown that transurethral resection of bladder tumors (TURBT) and partial cystectomy are the preferred treatment modalities. Additionally, pathogenic SDHB variants are associated with an increased risk of metastatic disease. However, due to the limited sample sizes in prior studies, overall survival rates remain difficult to estimate.

This case underscores the critical importance of accurate diagnosis and appropriate treatment strategies to improve patient outcomes.