Paraganglioma of urinary bladder.

The literature is reviewed and 2 new cases of paraganglioma of the urinary bladder, 1 malignant and 1 benign, are presented. One patient had no classic symptoms of vesical paraganglioma, and diagnosis was made postoperatively by means of light and electron microscopy. Differentiation between malignant and benign endocrine tumor cannot be made histopathologically and biochemically. The preoperative diagnosis of bladder paraganglioma is established when there is a combination of atypical urinary symptoms and elevation of catecholamines in the urine or blood. The risk of dangerous vasomotor changes needs a multi-team approach for diagnosis and surgical treatment. The pathologic features, histochemical reactions, ultrastructural characteristics, histogenesis, methods for early diagnosis, and detection of multiple localizations or metastasis are briefly discussed. A precise family history should be obtained in any patient with an extra-adrenal paraganglioma to facilitate early diagnosis of tumors in previously unaffected family members or of additional tumors in affected relatives.