Functional paraganglioma of the bladder: Both radiographic‐negative and laboratory‐negative case

Introduction Paraganglioma has been determined to be an extra-adrenal pheochromocytoma. Paraganglioma of the bladder is a rare entity, accounting for 0.06% of all bladder tumors. Case presentation A 58-year-old woman had been annually followed up since being diagnosed with rectal cancer 5 years ago. In January 2018, follow-up computed tomography detected a bladder tumor, and she was referred to our department for a further examination. Cystoscopy revealed a submucosal tumor on her right bladder wall. We performed transurethral resection of the bladder tumor. When we first marked the tumor margin, the systolic blood pressure increased, so we abandoned resection. We performed meta-iodobenzylguanidine scintigraphy and acid urinary collection, neither of which revealed any abnormal findings. We therefore performed open partial cystectomy based on a clinical diagnosis of paraganglioma of the bladder. The pathological findings revealed paraganglioma of the bladder. Conclusion We herein report a case of paraganglioma of the bladder.