Extraadrenal Retroperitoneal Paragangliomas: Radiologic Pathologic Correlation

ABSTRACT

PURPOSE: Retroperitoneal paraganglioma is a relatively uncommon neurogenic tumor, arising from paraganglial tissue. In our knowledge, there is few report about the radiologic findings of extraadrenal paraganglioma, therefore, here we document the adiologic findings of retroperitoneal paraganglioma with pathologic correlation. MATERIALS AND METHODS: In 5 patients with surgicopathologically confirmed extraadrenal paraganglioma and 1 clinjcolaboratorily confirmed case, we analyzed the ultrasonographic, computed tomographic and MRI findings, and correlated them with gross pathologic specimen. RESULTS: The location of the tumors was medial aspect of left kindey(n=2), superomedial aspect of right kidney hilum(n=2), and organ of Zuckerkandl area(n=2), UItrasonoram showed well-marginated mass(n=5), occasionally with irregular central necrosis with or without partially echogenic area suggesting hemorrhage(n=2). CT scan also showed well-marginated mass(n=6) with hemorrhagic necrosis(n--3) and contrast enhancement. One showed are shaped calcification along the capsule, and another case showed adhesion with aorta. In MRI, solid portion of the mass showed relatively low signal intensity on T1WI, increased signal on T2WI, and enhancement with gadolinium. Necrotic portion showed increased signal intensity on T1WI, and also showed increased signal intensity on T2WI, without contrast enhancement. Grossly the mass showed internal hemorrhagic necrosis of variable degree(n=6). CONCLUSION: If well-marginated mass is noted around the area of paraganglial distribution including organ of Zuckerkandl, especially with evidence of hemorrhagic necrosis and contrast enhancement, we must consider the possibility of paraganglioma despite no characteristic symptoms.