Paraganglioma of the urinary bladder first presented by bladder bloody tamponade: two case reports and review of the literatures.

Pheochromocytomas and paragangliomas (extra-adrenal pheochromocytomas) are catecholamine-secreting tumors. The paraganglioma of the urinary bladder is an uncommon neoplasm with a higher malignancy rate. Only about 60% of bladder paragangliomas presented with hematuria, and most of them were microscopic hematuria. Herein, we report two cases of bladder paraganglioma with bladder bloody tamponade. In Case 1, radical cystectomy and regional lymphadenectomy were performed for a huge bladder tumor and left pelvic lymph nodes metastasized. In Case 2, we chose endoscopic transurethral resection of the bladder tumor. Literatures since 1989 were also reviewed to illustrate the clinical characteristics and current treatments.