Palla and colleagues reported a case of a malignant bladder paraganglioma in a 45-year-old woman. Paragangliomas are pheochromocytomas that arise outside of the adrenal medulla. According to the "rule of tens," 10% of pheochromocytomas occur outside of the adrenals; however, the actual incidence of paragangliomas has been reported to be as high as 23%. These tumors may arise in the headeck, thorax, and/or abdominopelvic regions. Bladder paragangliomas, in particular, represent 0.06% of all bladder tumors and less than 1% of all cat-echolamine-secreting tumors. Pheochromocytomas normally arise from chromaffin cells in the adrenal medulla. Chromaffin tissue is also located along die para-aortic sympathetic chain, the sympathetic chain in the neck and mediastinum, and within die wall of the urinary bladder. The source of the bladder chromaffin tissue is uncertain. Some researchers suspect that chromaffin tissue migrates to the bladder wall during embryonic development.
展开▼
