Paraganglioma (pheochromocytoma) of the urinary bladder: A systematic review with a diagnostic, management and treatment algorithm

Introduction: Paraganglioma of the urinary bladder is a rare but well-documented tumour. Herein, we provide the largest, comprehensive systematic review of the literature and aim to increase familiarity with this rare but significant neoplasm. Methods: A systematic review of the literature was conducted on the NCBI PubMed database. The search criteria were not limited to any specific years or languages. There were 418 articles between January 1953 and August 2020, of which 255 case reports were selected. Results: Paragangliomas of the urinary bladder most commonly occurred in Caucasians in the fifth decade of life, most commonly presenting with haematuria and variations of 'micturition attacks'. Eighty percent of tumours were functionally active. The mucosa was normal in 91% of patients. In all, 25% of tumours were treated with transurethral resection alone, 65% had partial cystectomy and 5% had radical cystectomy. Alpha-blockers were administered pre-operatively in 38% of patients and the risk of intra-operative hypertensive crisis was over three times greater in those who did not receive an alpha-blocker. The tumour was confined to the bladder in 75% of cases. Metastasis occurred in 20% of cases, most commonly to iliac nodes. The mean follow-up time was 26.5 months. In cases that documented follow-up, 18.6% had recurrence, most commonly in lymph nodes and bone. Conclusion: All patients presenting with micturition attacks or haematuria with a computed tomography showing an enhancing, well-defined submucosal bladder lesion and/or cystoscopy showing a lesion with normal overlying mucosa should be worked up for a possible paraganglioma of the urinary bladder.