Successful Treatment of Coexisting Paraganglioma of the Retroperitoneum and Urinary Bladder by Intermediate-Dose 131I-MIBG Therapy: A Case Report.

Paragangliomas (PGLs) are rare neuroendocrine neoplasms of the autonomic nervous system dispersed from the skull base to the pelvic floor. We reported an extremely rare case with coexisting PGL of the retroperitoneum and urinary bladder. The patient complained of episodes of severe headache and palpitation during micturition, with a 1-year history of uncontrolled hypertension. The (131)I-metaiodobenzylguanidine ((131)I-MIBG) scintigraphy revealed high uptake in both of the retroperitoneum and urinary bladder mass accompanied with increasing 24 hour urinary norepinephrine and epinephrine. The patient received 6 doses of high-specific activity (131)I-MIBG from October 2009 to April 2015, each treatment dose was 400 mCi. The patient got symptomatic, hormonal, and radiographic tumor complete response without life-threatening adverse events.Intermediate-dose (131)I-MIBG therapy may be an alternative choice for patients with multicentric PGLs with positive MIBG scintigraphy.