[Malignant paraganglioma of the retroperitoneal space developing with increased arterial pressure]

Brief literature data on clinico-morphologic manifestation of retroperitoneal paraganglioma and its differential diagnosis with ectopic pheochromocytoma is presented. A female 31-year old patient is described with a rapid growth of retroperitoneal neoplasm and a concomitant increase of arterial blood pressure, first paroxysmal and then permanent. After the tumor excision (10 X 13 X 16 cm in size), not connected with the adrenal, the blood pressure recovered. The morphologic study provided the evidence for malignant paraganglioma different from ectopic pheochromocytoma in structural polymorphism and small size of neurosecretory granules. The arterial blood pressure increase is suggested to be due to tumor compression on the left kidney vessels.